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Cave Man
Nov 14, 2007, 03:04 PM
(Updated 15 March, 2008)

With the Apple TV 2 update, Dolby Digital 5.1 surround sound in now possible. This post provides information about how to get your system set up for 5.1 surround sound. If any of this is incorrect, I welcome and appreciate corrections by other forum members. As new information becomes available, I will revise this post.

1. Definitions

A. Dolby Digital AC-3 (DD). This is usually 6 channels (termed '5.1') that is sent over a digital connection, either by HDMI or optical cables from the Apple TV to a receiver with the respective inputs. The channels for DD are L, R, C, Rr, Lr and the low frequency LFE channel. The LFE is the '.1' channel.

B. Dolby Pro Logic II (DPLII). This is a 5-channel surround signal that can be sent over analog or digital connections. The 5 channels are R, L, C, Rr and Lr. DPLII also can be encoded and transmitted over stereo (i.e., 2 lines, right and left) cables to a receiver that is capable of decoding the signal and outputting to all 5 channels.

C. Dolby Pro Logic (DPL) (and Dolby Surround, DS). This is a 4-channel surround signal that can be sent over analog or digital connections. The 4 channels are right (R), left (L), center (C) and rear (r - two signals Rr and Lr, but it is mono so only counts as one channel). DPL can be encoded and transmitted over stereo cables to a receiver that is capable of decoding the signal and outputting to all 4 channels.

In Apple TV files DPLII, DPL, DS and stereo are encoded in AAC tracks.

You can read more about these from the pulldown at Dolby's surround sound web page.

http://www.dolby.com/resources/tech_library/index.cfm

2. Hardware

A. Apple TV. The Apple TV has three means of delivering audio: over the HDMI cable, through its optical port, and through its two channel RCA jacks. While the HDMI and optical port can deliver both digital (DD) and analog (DPL, DPLII, DS, stereo), the RCA jacks can only deliver analog audio.

B. TVs. Many new TVs have inputs for HDMI and optical cables, as well as analog RCA jacks. However, most only decode Dolby Digital delivered through their ATSC tuners (e.g., over-the-air antenna, satellite or cable connections). They generally are unable to decode DD from other hardware sources, such as an Apple TV or DVD player. In addition, they cannot passthrough DD from a device to a receiver; the TVs can only pass analog audio to the receiver. The exception to this rule is the built-in ATSC tuners that all new TVs have. These connections from a TV to a receiver are HDMI, optical cable or coaxial cable, each of which is capable of delivering digital audio information to the receiver.

C. Receivers/Amps. Most receivers today have the ability to receive and decode Dolby Digital audio (and DTS digital audio, but which will not be discussed since the ATV2 does not do DTS). The least expensive units have optical and/or coaxial digital audio inputs, often more than one, while the more expensive units have these inputs as well as HDMI inputs. In addition, some of the receivers with HDMI inputs also have HDMI outputs and can be used to control your video as well. These HDMI receivers are able to provide DD 5.1 surround while also passing along video to your TV.

3. Software

A. Quicktime Player. With the release of the Apple TV 2 update, Quicktime for the ATV2 saw an update with the ability to passthrough AC-3 Dolby Digital (e.g., 5.1) surround sound, provided the movie file has such a track and that a receiver capable of decoding DD is connected directly to the ATV. This feature of autoselecting audio tracks in ATV's Quicktime apparently is not available for Macs, although Quicktime on Macs can passthrough AC-3 DD if the track is enabled (and with DVDs and DVD Player app).

B. Handbrake. With the release of version 0.9.2, Handbrake (http://handbrake.fr/) included the ability to encode videos with both AAC (analog) and AC-3 5.1 (digital) surround sound, provided your source DVD has 5.1 surround sound tracks. By choosing the "Apple TV" preset in Handbrake, you get both audio tracks, with the AAC turned "on" and the AC-3 turned "off" by default. (This is also how the high-def with DD movie rentals from Apple are arranged, too.) The new Quicktime that ships with the ATV2 update automatically determines if (1) the movie file has an AC-3 track and (2) if your receiver is capable of decoding AC-3 audio. If both conditions are true, then the ATV will enable the AC-3 track. Otherwise, the ATV will only use the AAC track as the audio source.

4. Connections

A. Non-HDMI Receiver. If your receiver does not have HDMI inputs, then your best solution is to connect your Apple TV to your TV by its HDMI cable or component cables, then use a Toslink cable to connect your ATV to your receiver. You cannot connect your Apple TV to your TV with HDMI or optical cable and expect your TV to passthrough DD 5.1 to your receiver. The receiver must be connected directly to the ATV by optical cable. The audio can only be passthroughed once (but video can be passed at least twice). This is because of Digital Rights Management issues. If your TV does not have HDMI and you are using the component video connections from your ATV, then you should also connect your ATV audio to your TV using the RCA audio jacks.

B. HDMI Receiver. If your receiver has HDMI inputs, connect your ATV to it using an HDMI cable. You then need to connect your receiver's video-out to your TV, either by HDMI, component or composite cables. In this way, you will get DD 5.1 surround sound.

C. Listening to audio without having your TV on. If you listen to music, audio books or audio podcasts with the ATV, you may not want your TV on while using these media. If your RCA jacks on your ATV are unused, you can connect them to your receiver in such a way that it is unnecessary to leave your TV on while listening to audio media. For my setup, I have our ATV connected to our TV by HDMI, and to our Onkyo receiver by its optical cable. Because the RCA jacks on our ATV were unused, I connected them to the "CD" input on the receiver. With this setup, I set the receiver to CD mode, then start a music playlist from the ATV, then turn off the TV. The music continues to play until the last song.

See this post (http://forums.macrumors.com/showthread.php?p=5162084#post5162084) for the break in this thread between ATV2 and ATV1.


*******************************************************
* The information below is the original post and applies to
* pre-ATV2 only. If you still use versions 1.0 or 1.1, you should
* use this information.
*******************************************************

OK, I'm going to try to clarify audio on an Apple TV versus a Mac Mini. I hope to be clear and accurate, but your mileage may vary. I'm only going to discuss Dolby Labs' technology, and not DTS. I am no expert, but this is the information I've manage to pull together. If any of this is incorrect, I welcome and appreciate corrections by other forum members. As new information becomes available, I will revise this post.

1. Definitions

Dolby Pro Logic (DPL) (and Dolby Surround, DS). This is a 4-channel surround signal that can be sent over analog or digital devices. The 4 channels are right (R), left (L), center (C) and rear (r - two signals Rr and Lr, but it is mono so only counts as one channel). DPL can be encoded and transmitted over stereo (i.e., 2 lines, right and left) cables to a receiver that is capable of decoding the signal and outputting to all 4 channels.

Dolby Pro Logic II (DPLII). This is a 5-channel surround signal that can be sent over analog or digital devices. The 5 channels are R, L, C, Rr and Lr. DPLII also can be encoded and transmitted over stereo cables to a receiver that is capable of decoding the signal and outputting to all 5 channels.

Dolby Digital AC-3 (DD). This is usually 6 channels (termed '5.1') that is principally sent over a digital connection, such as a TOSLINK optical cable from the Mac Mini or Apple TV's optical audio port (but is currently nonfunctional on the ATV because of software limitations) to a receiver. The channels for DD are L, R, C, Rr, Lr and the low frequency LFE channel. The LFE is the '.1' channel.

You can read more about these from the pulldown at Dolby's surround sound web page.

http://www.dolby.com/resources/tech_library/index.cfm

2. Hardware

Apple TV. It has an audio chip that can decode up to a 7.1 signal. It has both optical audio out (which is capable of delivering a DD signal, but currently is not implemented) and RCA stereo jacks (which are analog and can thus deliver DPL or DPLII, but not DD, signals). The Apple TV uses Quicktime to play its video content and encoded AAC audio (which is distinct from AC-3 audio). It does not have DVD Player application that ships will all Macs.

Mac Mini. I do not know what the audio chip is inside the Intel-based Minis, but it is capable of at least 5.1 audio passthrough using its optical audio-out port (which is also a dual-function analog stereo-out port). If you connect a TOSLINK cable to it you get optical output (DD, DPLII, DPL, DS, Stereo). If you connect a 1/4" stereo to RCA cable to it you get analog (stereo, DPL, DPLII, but not DD) output. The Mac Mini can use Quicktime or DVD Player to play video content, depending on the file type.

3. Software

DVD Player. This program on the Mac Mini is capable of sending Dolby Digital AC-3 audio data through the optical port of a Mac Mini via a TOSLINK cable. It cannot send AC-3 out via a stereo-to-RCA cable. If you play a DD 5.1-encoded DVD (real or ripped to your hard drive with MacTheRipper) using DVD Player and you have a TOSLINK cable between your Dolby Digital-capable receiver and Mac Mini, DVD Player will passthrough the AC-3 info to the receiver, which will decode it into all 6 channels (L, R, C, Lr, Rr, LFE). This will give you 5.1 surround sound. If the DVD only has DPL, DPLII or 2-channel stereo, then only those can be passed through. You cannot get 5.1 surround from DPLII, DPL or stereo audio.

Quicktime Player. The program is found on the Mac Mini as well as the Apple TV. Since it cannot decode AC-3 audio files, there is currently no way to get AC-3 audio (i.e., 5.1 surround) from Apple TV to a 5.1 receiver. Quicktime is capable of encoding 6 discrete audio channels, but they are in AAC, not AC-3. Since there are no consumer receivers on the market that can decode AAC, you cannot get 5.1 surround sound from the Apple TV or Mac Mini using Quicktime. Quicktime will, however, allow the playback of stereo and since DPL and DPLII can be encoded in stereo channels you can get 4-channel (DPL) or 5-channel (DPLII) audio from your Apple TV or Mac Mini, provided they are connected to a receiver capable of decoding DPL or DPLII. (Note, though, that there is usually channel leakage in DPL and DPLII, thus separation is not as good as it is with DD.)

Handbrake. With the release of version 0.9, Handbrake (http://handbrake.m0k.org/) included the ability to convert DD AC-3 into DPLII 5-channel surround in the transcoded Quicktime video file. If you select the Apple TV preset for a DVD with 5.1 AC-3, Handbrake will convert the 5.1 AC-3 file into a DPLII stereo audio track (see "Track 1 Mix" on attached screen shot) of the H.264 output MPEG4 file and it will contain the L, R, C, Rr, and Lr channels, but not the LFE channel. If you play this on the Apple TV using a TOSLINK cable (or the RCA jacks) to connect the ATV to your DPLII-capable receiver, you will get 5-channel surround (but not 5.1 surround). Handbrake also has a provision to convert the 5.1 AC-3 audio into 6 discrete channels encoded in AAC in Quicktime; however, as mentioned above, since there are no consumer receivers on the market today that can decode AAC from Quicktime audio there's really not much point in using this feature of Quicktime. I have tried this, and it does play on my Onkyo receiver, but it is not 5.1 surround.

VLC. Handbrake can also be used to transcode DVDs into MKV format containers with H.264 video encoding and Dolby Digital AC-3 5.1 surround sound passthrough (see second attachment). These files will not play in Quicktime, thus cannot be used for playback on the ATV. However, VLC (http://www.videolan.org/vlc/download-macosx.html) will play them on a Mac and passthrough the AC-3 audio file through the optical port to a receiver using a Toslink cable. (Install Perian (http://perian.org/) for good measure.) Provided your receiver has an optical input and the ability to decode Dolby Digital, you can get 5.1 surround sound with your movies. One word of caution: VLC is very buggy and skipping ahead can cause all kinds of problems with crashing VLC, and also crashing your audio in such a way that the only fix is to reboot your Mac. In addition, these files are typically much larger than MP4 H.264 stereo/DPL/DPLII files because of the size of AC-3. A 2 gig movie with MP4/DPLII will be about 3 gigs as an MKV/AC-3.

DVD2OneX. DTOX (http://www.dvd2one.com/) is an app that will take a DVD ripped to your hard drive with MacTheRipper (http://www.mactheripper.org/) and compress it to a smaller size. One preset is to make it small enough that you can fit it on a single-layer DVD. You can use it to clone the DVD or to make a DVD for individual videos from the DVD. If you have Leopard on your Mac, Front Row will now allow you to play DVDs from your hard drive. Because of this, I have my 5.1 surround sound-intensive DVDs MTR/DTOX'd to 4.2 gig VIDEO_TS folders for playback on my Mac Mini home theater system. Its much cleaner and reliable than playback of MKV files with VLC. I have an external firewire drive with a folder called 'DVD' in which these VIDEO_TS folders are stored, and an alias to the DVD folder is copied to my Home/Movies folder. When Front Row is launched, select Movies, then drive down to the DVD folder of your choice. Of course, these ripped VIDEO_TS folders can also be played by DVD Player with passthrough of the 5.1 surround sound to your receiver, as well.



Cave Man
Nov 14, 2007, 06:00 PM
If anyone is looking for a 5.1 home theater surround sound system, the Onkyo HT-SR600 (http://www.us.onkyo.com/model.cfm?m=HT-SR600&class=Systems&p=i) is very inexpensive and provides optical input for the Apple TV or Mac Mini. It only has component video input (no HDMI or DVI), but component is still very good. B&H Photo (http://www.bhphotovideo.com/c/product/484719-REG/Onkyo_HT_SR600B_HT_SR600_5_1_Channel_Home_Theater.html) sells it for $240 and Circuit City (http://www.circuitcity.com/ccd/Search.do?c=1&searchType=user&keyword=HT-SR600&searchSection=All&go.x=0&go.y=0) currently has it on sale for $270. I've not actually heard this unit, but it is descendent of the Onkyo system I have (HT-S580). It will decode Dolby Digital and DTS (both 5.1), should the ATV (and Quicktime) ever get there. It also does Dolby Pro Logic II (5-channel) and below.

jim.arrows
Nov 14, 2007, 09:32 PM
Nice post, thanks for taking the time to summarize; I own 2 ATVs and have been thinking of converting my dvd collection to h.264, so I'm glad to know that I'll lose discrete surround and the LFE channel if I do so at this point. I see no point in tackling this project at present, as I'm sure if the capability is added in the future any current rips will have to be repeated, and I only want to have to do this once. Thanks again!

Duffinator
Nov 14, 2007, 09:45 PM
Nice post, thanks for taking the time to summarize; I own 2 ATVs and have been thinking of converting my dvd collection to h.264, so I'm glad to know that I'll lose discrete surround and the LFE channel if I do so at this point. I see no point in tackling this project at present, as I'm sure if the capability is added in the future any current rips will have to be repeated, and I only want to have to do this once. Thanks again!Agreed. Unless you retain DD or DTS it's pointless to rip at this time. Hopefully that will be resolved in the near future.

I started a similar thread a while back discussing the audio output of the ATV here. (http://forums.macrumors.com/showthread.php?p=4282162#post4282162)

Cave Man
Nov 14, 2007, 10:35 PM
It seems to me that the path of least resistance would be to store the files for ATV as discrete 6-channel AAC audio, then have the ATV convert it to AC-3 or DTS (probably requiring licensing from Dolby and/or DTS) on the fly as it sends it out the optical port. I don't know if the processor is powerful enough to do that and deal with decompression to 720 video (through the GPU) concurrently.

Certainly, storing AC-3 audio data is not an option. It is simply too big for Apple's model of movie downloads, either for purchase or rental. Put on top of that the video requirements for 720, you're going to have 4 gig files to download for a 2 hour 5.1 movie. I just don't see that happening. AAC is the way to go.

So, any thoughts on the ATV's ability to decode H.264 and convert AAC to AC-3/DTS in real-time? What about conversion to Neo6 - that should be faster, right?

TuckBodi
Nov 15, 2007, 01:57 PM
Excellent write-up Cave Man! Here's some additional info from Roughly Drafted which I also found informative.

The 10 Myths of Apple TV 5.1 Audio:

http://www.roughlydrafted.com/RD/RDM.Tech.Q1.07/147048D8-D8B7-45E7-9A97-3CD5B4C2B75A.html

saltyzoo
Nov 15, 2007, 02:13 PM
I apologize for derailing the thread to some degree, but does anybody know of an easy way to connect a mini (toslink) to a receiver with discrete 5.1 RCA inputs (IE: 6 RCA jacks)?

Superman07
Nov 15, 2007, 05:26 PM
I apologize for derailing the thread to some degree, but does anybody know of an easy way to connect a mini (toslink) to a receiver with discrete 5.1 RCA inputs (IE: 6 RCA jacks)?

I imagine you'd have to get a converter (if one exists). Your best bet would probably be to check over at AVS.

Cave Man - Also a thanks for the write up. So even if Apple were to upload the software for the chip to decode 5.1, it wouldn't do any good since the software (Quicktime) would not be able to read the data from the file?

Cave Man
Nov 15, 2007, 06:10 PM
So even if Apple were to upload the software for the chip to decode 5.1, it wouldn't do any good since the software (Quicktime) would not be able to read the data from the file?

If it's solely software, then they can add it to Quicktime. The problem is that AC-3 and DTS audio files are very large. This is why AAC is so attractive - it is an efficient compression algorithm. But even then, if you have 6 audio signals, that's a lot of information for a H.264 720p video file (which we're all hoping for) that needs to be downloadable from iTMS. Perhaps most limiting, though, is the lack of recievers that can decode AAC. The only 5.1 capable receivers I know of can decode AC-3 and DTS. There are some on the market that can decode Neo6, which is a highly compressed 6 channel from DTS.

If you want the smallest files, I think Apple has to do discrete 6-channel AAC in Quicktime and license the compression algorithms from Dolby or DTS to convert the AAC to one of these formats on the fly, then send it out the optical port to your 5.1 receiver for decoding. It's a tough one to call.

The specs on the chip are here (http://www.realtek.com.tw/products/productsView.aspx?Langid=1&PFid=28&Level=5&Conn=4&ProdID=138). I'm not a hardware guy, but it seems to me that this chip can support a variety of audio sources and is S/PDIF (http://en.wikipedia.org/wiki/S/PDIF), so it can do the passthrough of DD or DTS without decoding it since it's just a data file (I presume).

peeaanuut
Nov 15, 2007, 06:49 PM
ok so my question is this. Do most of you have your aTV plugged in via the optical port or the rca jacks? I only have mine via the optical port and it seems to be just fine.

tronic72
Nov 15, 2007, 10:13 PM
I have been looking into this issue since I purchased my Apple TV a few months ago. I must admit I was pretty disappointed the find that it only worked in Stereo but that is really the only issue I have with my Apple TV.

That said, your post, like many others provides more questions on of which is:

Q: I encode my DVDs using Handbrake so I assume that the surround signal is there but the Apple TV simply can't play it. Is this correct? I can only assume that it is otherwise why else would Handbrake have the settings for surround sound as shown in the image you've posted.

Surely the way to test this is to play the file on a Mac Mini or other Mac using the toslink connection.

If this is correct, then I think the next step would be to boot a hacked Apple TV into Mac 10.4.8 and see if the file can be played through Quicktime player in OS X. Has anyone ever done this? Am I missing a step?

If this IS possible then surely the issue is a software one.

If I'm missing something let me know.
:confused:

TuckBodi
Nov 15, 2007, 10:27 PM
I have been looking into this issue since I purchased my Apple TV a few months ago. I must admit I was pretty disappointed the find that it only worked in Stereo but that is really the only issue I have with my Apple TV.

That said, your post, like many others provides more questions on of which is:

Q: I encode my DVDs using Handbrake so I assume that the surround signal is there but the Apple TV simply can't play it. Is this correct? I can only assume that it is otherwise why else would Handbrake have the settings for surround sound as shown in the image you've posted.

Surely the way to test this is to play the file on a Mac Mini or other Mac using the toslink connection.

If this is correct, then I think the next step would be to boot a hacked Apple TV into Mac 10.4.8 and see if the file can be played through Quicktime player in OS X. Has anyone ever done this? Am I missing a step?

If this IS possible then surely the issue is a software one.

If I'm missing something let me know.
:confused:

**sigh**

Take a look at the link from Roughly Drafted I posted above and I think it'll answer your questions. From the article here is a snippet:

--RD--
DTS 5.1 from Apple TV
In addition to stereo cables, Apple TV also features a Toslink digital optical port. Since we can send raw digital audio data over the Apple TV's optical output, can't we send DTS digitally encoded 5.1 as well?

Of course we can. Download a DTS sample file in WAV format, drop it into iTunes, and Apple TV will happily sync it and play it. Unlike Pro Logic audio, it will sound like static over regular stereo speakers, but hooked up to a DTS receiver, it is decoded into 5.1 channels of sound and played back in real DTS 5.1 surround.

The only limitation with DTS 5.1 sound right now is that Apple isn't offering it on its own movie downloads. The Apple TV can certainly “do it,” because it doesn't have to “do” anything; it merely passes it on to the 5.1 DTS decoder that anyone with 5.1 surround speakers already has.
--RD--

Time will tell if Apple does anything now or just waits for AAC capable receivers to become more common. In the meantime, also check out the A52Codec (http://trac.cod3r.com/a52codec) and what people are doing with it.

tronic72
Nov 15, 2007, 10:47 PM
**sigh**

Take a look at the link from Roughly Drafted I posted above and I think it'll answer your questions. From the article here is a snippet:

--RD--
DTS 5.1 from Apple TV
In addition to stereo cables, Apple TV also features a Toslink digital optical port. Since we can send raw digital audio data over the Apple TV's optical output, can't we send DTS digitally encoded 5.1 as well?

Of course we can. Download a DTS sample file in WAV format, drop it into iTunes, and Apple TV will happily sync it and play it. Unlike Pro Logic audio, it will sound like static over regular stereo speakers, but hooked up to a DTS receiver, it is decoded into 5.1 channels of sound and played back in real DTS 5.1 surround.

The only limitation with DTS 5.1 sound right now is that Apple isn't offering it on its own movie downloads. The Apple TV can certainly “do it,” because it doesn't have to “do” anything; it merely passes it on to the 5.1 DTS decoder that anyone with 5.1 surround speakers already has.
--RD--

Time will tell if Apple does anything now or just waits for AAC capable receivers to become more common. In the meantime, also check out the A52Codec (http://trac.cod3r.com/a52codec) and what people are doing with it.

OK, Call me thick if you want but I'm obviously missing something. I have an Apple TV and a surround sound Amp and like 99% of the population it's not AAC compatible. So I only ever see two speakers on the "little diagram" that usually lights up like a Christmas tree when connected to my DVD player. So I can only conclude that Apple TV is not sending a 5.1 signal that my Amp can decode. Is this correct?

Q: Will the codec you suggested remedy this?

Q: Should I just use my Mac Mini and front row instead? I want it simple as I spend all day in front of a computer and the last thing I want to do when I sit down in the evening is "fiddle"

Q: Why did Apple make this so hard??

Edit: By the way, I'm using the Optical connections on the Apple TV NOT the analogue.

Thanks for your advice and suggestions so far.

Cave Man
Nov 15, 2007, 11:56 PM
OK, Call me thick if you want but I'm obviously missing something.

Download this file (http://www.phototone.org/dplii.mp4) (3.3 mb Quicktime H.264 DPLII video) that was extracted from a Dolby Digital AC-3 5.1 video. If your browser opens it in a window, wait until it completely downloads into QT, then save the file from within the browser's Quicktime window by clicking on the little down-arrow in the lower right corner of the QT window.

On the DVD its audio is a 5.1 Dolby Digital file. However, it was extracted using Handbrake 0.9.1 with the Apple TV preset. Handbrake converted it to a Dolby Pro Logic II 5-channel (not 5.1-channel) file. This file can be transmitted over stereo R and L RCA cables (or the TOSLINK cable) to your amplifier. If your receiver/amplifier can decode DPLII (check your amp's manual) then you should get 5-channel surround sound by playing this file. I have tried it on my Mac Mini home theater system (Onkyo) using Quicktime and it really, truly is 5-channel surround. When you open the file in Quicktime, choose Window -> Show Movie Properties. On this window, select Sound Track, then Audio Settings. You will see that there are only 2 tracks; right and left. This is the beauty of DPLII - it is a 5-channel signal that can be stored on a 2-channel track. The Mini or ATV simply passes these two tracks to your DPLII-capable receiver/amp, which then decodes all 5 channels and sends them to the correct speakers: L, R, C, Lr, Rr. The only one that's missing is the low frequency (bass) LFE (which is the '.1' track in 5.1). Play it on your ATV or Mini with a DPLII surround sound system and you will hear for yourself that not only is it surround, it is pretty darn good. Only absolute separation of channels and the richness of the LFE are missing.

Q: Should I just use my Mac Mini and front row instead? I want it simple as I spend all day in front of a computer and the last thing I want to do when I sit down in the evening is "fiddle"

The only better (audio) aspect about the Mini is that DVD Player app on the Mini will give you AC-3 5.1 (6-channel, including the low frequency LFE) surround passthrough from your DVD VOB files to your DD/DTS amplifier, while the Quicktime on the Apple TV (or Mini, for that matter) can only give you 5-channel (Dolby Pro Logic II) from your Handbrake-ripped MPEG4 video files (provided you use the ATV preset that converts AC-3 5.1 to DPLII 5-channel).

Q: Why did Apple make this so hard??

Probably for proprietary reasons. Maybe increased file size (download problems from iTMS). No one knows why it's taking Apple so long to get this sorted out. If Dolby doesn't want to license DPLII to Apple, we may never see a solution. Maybe Apple's trying to leverage amplifier/receiver manufacturers to sell units that can decode Quicktime discrete 6-channel AAC. Your guess is as good as anyone's.

Edit: By the way, I'm using the Optical connections on the Apple TV NOT the analogue..

Either should work since the ATV is sending the encoded signal to your receiver, not the decoded signal, but the optical cable is better.

TuckBodi
Nov 15, 2007, 11:59 PM
OK, Call me thick if you want but I'm obviously missing something. I have an Apple TV and a surround sound Amp and like 99% of the population it's not AAC compatible. So I only ever see two speakers on the "little diagram" that usually lights up like a Christmas tree when connected to my DVD player. So I can only conclude that Apple TV is not sending a 5.1 signal that my Amp can decode. Is this correct?

Q: Will the codec you suggested remedy this?

Q: Should I just use my Mac Mini and front row instead? I want it simple as I spend all day in front of a computer and the last thing I want to do when I sit down in the evening is "fiddle"

Q: Why did Apple make this so hard??

Edit: By the way, I'm using the Optical connections on the Apple TV NOT the analogue.

Thanks for your advice and suggestions so far.

You also have a Mac mini? Then like the OP talks about, that sounds like your best bet as you have easier/better ways of passing surround through it (DVDPlayer, VLC, etc.). Trying to do surround sound with the ATV is a kludge. Yeah, good question, why did Apple make it so hard..

Side Note: It's interesting you have a mini and an ATV as I do as well. My setup consists of the ATV off my main TV, my Sammy LCD in the living room, while my mini is the media server and is connected to my bedroom's old Sony CRT (EyeTV, Frontrow, etc.). Thus is why I'm also very interested where Apple is going with the ATV and surround sound. :)

TuckBodi
Nov 16, 2007, 12:08 AM
Probably for proprietary reasons. Maybe increased file size (download problems from iTMS). No one knows why it's taking Apple so long to get this sorted out. If Dolby doesn't want to license DPLII to Apple, we may never see a solution. Maybe Apple's trying to leverage amplifier/receiver manufacturers to sell units that can decode Quicktime discrete 6-channel AAC. Your guess is as good as anyone's.

I've often wondered if it's the studios holding them hostage? Would it be that hard to offer a good, better, best version of the movie and make everybody happy and then update the ATV for the HD videos...

Cave Man
Nov 16, 2007, 12:21 AM
ok so my question is this. Do most of you have your aTV plugged in via the optical port or the rca jacks? I only have mine via the optical port and it seems to be just fine.

My ATV is through RCA cables. I only have R, L, and C speakers on my old Sony receiver, which is pre-optical cable days. My Mini is connected to my Onkyo receiver for my home theater - a projector-based system with a 10' wide screen. :D

Optical is the way to go, I would think. Less of an issue of cross-talk that can occur with poorly-insulated copper wires.

Cave Man
Nov 16, 2007, 12:24 AM
I've often wondered if it's the studios holding them hostage? Would it be that hard to offer a good, better, best version of the movie and make everybody happy and then update the ATV for the HD videos...

I really don't know. Hardware wise, the limitation are the receivers/amps. They only do DD or DTS for x.1 surround sound. There's also THX, but that's a lot more expensive. Software seems the easiest route to me, but you'd have to convince Dolby, DTS and Apple that everyone can have a slice of the pie.

Superman07
Nov 16, 2007, 07:22 AM
I thought about this some more last night and I may be tempted to jump in since I can us a lot of stuff I have now (older TV shows) that do not even have a 5.1 track.

However, based on TuckBodi's post it appears that ATV will support pass-through of DTS 5.1 data so that the receiver can prcoess the signal (over toslink). This is an accurate statement, correct?

Next question - if you're sending a DPLII signal from the ATV, even if it's 5.0, will the receiver still send a siganl to the sub? I imagine if the frequency was low enough, the sub would kick in even if there was crossover with the normal speakers.

Lastly - is there any way to transcode a DD signal to DTS? How about the way that that DD+ and DTS-HD are handled in new players? They are both, if I'm not mistaken, automatically downconverted in a DTS stream. Is this a software function or hardware? Perhaps the next version of ATV could use this solution?

Cave Man
Nov 16, 2007, 09:56 AM
Next question - if you're sending a DPLII signal from the ATV, even if it's 5.0, will the receiver still send a siganl to the sub? I imagine if the frequency was low enough, the sub would kick in even if there was crossover with the normal speakers.

The sub plays, it just doesn't produce the rich sound of a '.1' discrete LFE track. I've played Revenge of the Sith from both the DVD with DVD Player (5.1) and Handbraked H.264 DPLII (5-channel) with Quicktime and the DVD audio is noticeably (but not a whole lot) better than the DPLII. It sounds more spacious (because of absolute channel separation) and the sub really shakes the walls. :D With that said, though, DPLII is a lot better than just 2-track stereo audio. Some surround is better than no surround.

I can't answer your other two questions, but for the ATV the limitations are the software codecs. With the 1.1 update, Apple broke ssh and AFP, so to put any new codecs on the ATV you'd have to pull the drive out of the ATV and mount it on your Mac, then copy those Intel binary codecs to their proper places, and reassemble your ATV. It's not hard; after all, the ATV is simply OS X. However, Back Row specifically uses Quicktime for its video playback, so any codec would have to be compliant with the Quicktime installed on the ATV. Apple can do this for us with an update. But for whatever reason, they haven't.

Cave Man
Nov 16, 2007, 03:00 PM
I've often wondered if it's the studios holding them hostage? Would it be that hard to offer a good, better, best version of the movie and make everybody happy and then update the ATV for the HD videos...

It could be the studios. I don't know how much more (or less) they make off of HD videos (which is what Apple should be providing: 720p in 5.1 surround) sold in brick and mortar shops compared to iTMS. It's also a function of bandwidth. True 5.1 encodes 6 discrete audio channels that can significantly contribute to file size. The nice thing about AAC is it's very efficient - small file size but retaining high-quality sound. But even then, if you stick 6 AAC audio tracks onto a 720p HD video, you're talking some serious file sizes. I bought Ratatouille from the iTMS and it was something like 1.6 gb in size. That's a standard definition, two-channel stereo file of about 1 hour and 50 minutes in length. Make it 720p with 6-channel audio and it's probably going to be around 3 or 4 gigs in size (maybe more). That's almost an overnight download for my DSL bandwidth. I can't imagine how long it would take for a 1080i 5.1 file to download.

Cave Man
Nov 19, 2007, 11:41 PM
I extracted the audio from the DVD VOB file used to generated the H.264 file in my previous post, and here are the file sizes of each:

AC3 = 2.1 mb (6-channel surround)
AAC = 1.5 mb (6 discrete AAC channel surround)
DPLII = 628 kb (5-channel surround)

So, even if Apple could distribute their movies in AAC 5.1 surround, the file sizes would probably still be pretty hefty. Not good for downloads.

cohibadad
Nov 20, 2007, 01:59 AM
With the 1.1 update, Apple broke ssh and AFP, so to put any new codecs on the ATV you'd have to pull the drive out of the ATV and mount it on your Mac

I software hacked my ATV recently and have ssh and AFP without pulling the hard drive. I posted relative links in another thread if anyone is interested. It requires some command lines but wasn't really hard. I have 1.1.

Also, I downloaded the DTS file linked on the roughlydrafted post and it does play perfectly 5.1 streamed to ATV and displays as DTS. I use HDMI from ATV to my receiver.

Cave Man
Nov 20, 2007, 08:44 AM
Yes, I'd like to see that link for reestablishing ssh and AFP to a 1.1 ATV.

Thanks

cohibadad
Nov 20, 2007, 09:38 AM
sure. here is the link http://forums.macrumors.com/showthread.php?t=384664

I've been thinking about this 5.1 surround sound question. This is probably obvious to many but it should be possible to H.264 encode a movie with say handbrake then demux the audio and reencode the AC3 or DTS to WAV, combine them in QT and save in a MOV container that should play on :apple:TV, yes? The audio would sound like garbage on the mac unless passed through DTS/dolby decoder software, but if passed through a receiver it should work? I think I will try it with 1 chapter as a test. It would be pretty tedious to do a lot of movies without some automation though.

cohibadad
Nov 21, 2007, 01:25 AM
well after a lot of experimentation I have come to the following conclusions:

1. A valid DTS WAV audio track can be added to an M4V video track in QT, saved in a MOV and streamed to :apple:TV which will decode properly on a receiver and play 5.1. The trick is to actually make a DTS WAV file from a ripped VOB.
2. the A52Codec listed above does allow QT to use AC3 tracks which can be added to an M4V video track, saved in a MOV and streamed to :apple:TV which plays the file but my receiver does not recognize it as AC3. It plays it though. I loaded the component onto the :apple:TV also.
3. my handbraked videos with DLPII are not autorecognized by either of my receivers as DLPII. The linked video above is not either. Whether this is due to my receivers, handbrake, HDMI I don't know. But the DTS WAV file is correctly autorecognized.

Summary: Surround sound with :apple:TV is a difficult topic.

TuckBodi
Nov 21, 2007, 01:27 AM
well after a lot of experimentation I have come to the following conclusions:

1. A valid DTS WAV audio track can be added to an M4V video track in QT, saved in a MOV and streamed to :apple:TV which will decode properly on a receiver and play 5.1. The trick is to actually make a DTS WAV file from a ripped VOB.
2. the A52Codec listed above does allow QT to use AC3 tracks which can be added to an M4V video track, saved in a MOV and streamed to :apple:TV which plays the file but my receiver does not recognize it as AC3. It plays it though. I loaded the component onto the :apple:TV also.
3. my handbraked videos with DLPII are not autorecognized by either of my receivers as DLPII. The linked video above is not either. Whether this is due to my receivers, handbrake, HDMI I don't know. But the DTS WAV file is correctly autorecognized.

Summary: Surround sound with :apple:TV is a difficult topic.

Have you tried NitoTV with the mplayer option?

tronic72
Nov 21, 2007, 04:44 AM
well after a lot of experimentation I have come to the following conclusions:

1. A valid DTS WAV audio track can be added to an M4V video track in QT, saved in a MOV and streamed to :apple:TV which will decode properly on a receiver and play 5.1. The trick is to actually make a DTS WAV file from a ripped VOB.
2. the A52Codec listed above does allow QT to use AC3 tracks which can be added to an M4V video track, saved in a MOV and streamed to :apple:TV which plays the file but my receiver does not recognize it as AC3. It plays it though. I loaded the component onto the :apple:TV also.
3. my handbraked videos with DLPII are not autorecognized by either of my receivers as DLPII. The linked video above is not either. Whether this is due to my receivers, handbrake, HDMI I don't know. But the DTS WAV file is correctly autorecognized.

Summary: Surround sound with :apple:TV is a difficult topic.

I agree. I think these technical posts only confuse people and blur the real issue. For all the similar technical posts out there, I think your summary is the most apt and accurate regarding Surround Sound on Apple TV.

I think it's best to say that in it's current state, for 99.999% of the population, the Apple TV doesn't support surround sound. I still love mine but I'd just love it more if it had 5.1 surround.

cohibadad
Nov 21, 2007, 12:06 PM
I agree. I think these technical posts only confuse people and blur the real issue. For all the similar technical posts out there, I think your summary is the most apt and accurate regarding Surround Sound on Apple TV.

I think it's best to say that in it's current state, for 99.999% of the population, the Apple TV doesn't support surround sound. I still love mine but I'd just love it more if it had 5.1 surround.

I agree.

Apple TV is funny with surround sound. My receivers will not autorecognize a surround sound signal from it (blue light doesn't come on and it does not display dolby signal) but if I manually select dolby processing it does sound like it is surround. Receiver does autorecognize every other input as surround. Very odd. Well, for now I will continue to encode with DPLII. Not worth the effort to use AC3 or DTS with questionable returns at this point. I wonder if Apple downloads would be autorecognized and decoded? Has anyone tried this?

Cave Man
Nov 22, 2007, 11:09 AM
I think it's best to say that in it's current state, for 99.999% of the population, the Apple TV doesn't support surround sound. I still love mine but I'd just love it more if it had 5.1 surround.

I don't think this is really true at all. If you can use Handbrake, then you can get DPLII with the click of a button. The Apple TV preset of Handbrake defaults to DPLII 5-channel surround, provided the DVD has Dolby Digital. All you need next is to add the file to your iTunes library and make sure your ATV is connected to a DPLII-capable receiver. Voila - you have 5-channel surround sound. Depending on the receiver/amp, you can also get pretty good low frequency audio. My Onkyo does a very good job at this.

Your statement is true if you're talking about 5.1 exclusively, but "surround sound" at a minimum is 4-channel (DPL).

Cave Man
Nov 22, 2007, 11:16 AM
Apple TV is funny with surround sound. My receivers will not autorecognize a surround sound signal from it (blue light doesn't come on and it does not display dolby signal) but if I manually select dolby processing it does sound like it is surround.

This isn't a function of the ATV, it's a function of the audio matrix. The ATV doesn't "tell" the receiver to switch to some decoding algorithm; the receiver should detect it in the audio track if it is programmed to do so. I don't have any "native" sources with DPLII encoded, so I cannot tell if this might be the case with my system.

Receiver does autorecognize every other input as surround. Very odd.

If the receiver is not programmed to detect DPLII and autoswitch to it, it might not be odd at all. My Onkyo autoswitches for DD, Dolby Surround and DTS, even when I'm watching broadcast TV with my Eye TV Hybrid. Regardless, the DPLII light is always on on my receiver.

Well, for now I will continue to encode with DPLII. Not worth the effort to use AC3 or DTS with questionable returns at this point. I wonder if Apple downloads would be autorecognized and decoded? Has anyone tried this?

As far as I know, none of the iTMS videos are encoded in anything other than stereo.

Cave Man
Dec 9, 2007, 09:37 PM
Download this file (http://www.phototone.org/dplii.mp4) (3.3 mb Quicktime H.264 DPLII video) that was extracted from a Dolby Digital AC-3 5.1 video. If your browser opens it in a window, wait until it completely downloads into QT, then save the file from within the browser's Quicktime window by clicking on the little down-arrow in the lower right corner of the QT window.


I've uploaded another file (http://www.phototone.org/AC3.mkv) that is the same as the one referenced above. However, this one was encoded with Handbrake to produce an MKV file using H.264 compression and AC3 5.1 AC3 Dolby Digital passthrough. If you have Perian installed on your Mac and play this file through VLC, and your Mac is connected by Toslink to a receiver capable of decoding DD, you will get 5.1 surround sound.

Note, this file is 4.2 mb in size compared to 3 mb in size for the DPLII version. If this rate holds up, then you can expect any Dolby Digital 5.1 movies that might become available on the iTMS to be about 30% larger than non-DD files. As an example, King Kong encoded as DPLII is 2.6 gb, while the AC3 DD version is 3.9 gb. If you make the video 720 HD, you're talking about 3.5 times more video size. I suspect such a movie would be about 10 gb in size. This is the inherent problem with Apple selling such content - we really need better bandwidth for this type of service.

bmb012
Dec 10, 2007, 04:54 AM
A receiver isn't going to recognize a PLII file as surround, because it really isn't. It's a stereo stream, and the receiver takes audio that sounds like it should be surround (it sounds muffled), and throws it in the back.

By 'encoding' into PLII, all you're doing is ripping the 5.1 track as stereo, and letting the decoder use algorithms to put audio that sounds like it should be in the back in the back, and sounds that are the same in both speakers (like voice tracks) into the center channel.

I actually read somewhere that the 360 now supports aac 5.1 audio with the latest update, but I haven't been able to test out out yet. Don't see why it wouldn't, as it can mix iPod audio into the 2 front channels while sending a 5.1 digital track, the thing is constantly encoding 5.1 in realtime anyway.

tronic72
Dec 11, 2007, 05:37 AM
I don't think this is really true at all. If you can use Handbrake, then you can get DPLII with the click of a button. The Apple TV preset of Handbrake defaults to DPLII 5-channel surround, provided the DVD has Dolby Digital. All you need next is to add the file to your iTunes library and make sure your ATV is connected to a DPLII-capable receiver. Voila - you have 5-channel surround sound. Depending on the receiver/amp, you can also get pretty good low frequency audio. My Onkyo does a very good job at this.

Your statement is true if you're talking about 5.1 exclusively, but "surround sound" at a minimum is 4-channel (DPL).


"make sure your ATV is connected to a DPLII-capable receiver" Therein lies the problem.

Many Amps don't support this and I for one and not going to change my $2000 Amp because Apple has decided NOT to follow convention and use a commonly used format. When will they learn???

Apple has created many duds by using non popular, or close source standards. Just look at M$ and how unpopular they've become with their closed standards. Remember how expensive peripherals used to be for the mac before they embraced USB? I know ACC is not the same as open or closed source, but the point I'm trying to make is; Apple stuffed up by not following convention with the Apple TVs audio. They used all the right connectors but they didn't get the internals right.

I think it's sad that Apple didn't simply make this product with the same audio support as a $50 DVD player :(

bmb012
Dec 11, 2007, 05:47 AM
The biggest problem is that the AppleTV itself doesn't suport aac... it should be able to decode the 5.1 aac and encode it into 5.1 Dolby...

saltyzoo
Dec 11, 2007, 05:49 AM
"make sure your ATV is connected to a DPLII-capable receiver" Therein lies the problem.

Many Amps don't support this and I for one and not going to change my $2000 Amp because Apple has decided NOT to follow convention and use a commonly used format. When will they learn???

Apple has created many duds by using non popular, or close source standards. Just look at M$ and how unpopular they've become with their closed standards. Remember how expensive peripherals used to be for the mac before they embraced USB? I know ACC is not the same as open or closed source, but the point I'm trying to make is; Apple stuffed up by not following convention with the Apple TVs audio. They used all the right connectors but they didn't get the internals right.

I think it's sad that Apple didn't simply make this product with the same audio support as a $50 DVD player :(

I must be misunderstanding you. Are you suggesting that DPLII Is unconventional / non standard?

tronic72
Dec 11, 2007, 05:58 AM
I must be misunderstanding you. Are you suggesting that DPLII Is unconventional / non standard?

Sorry. Upon reading it my post it a bit confusing.

The point i was trying to make is they didn't follow convention. The device should have had the same audio capabilities as the cheapest DVD player does. It should have been simply plug and play. After all, Apple are the masters of Plug & Play devices.

Sorry for the mix up.

displaced
Dec 11, 2007, 06:16 AM
A receiver isn't going to recognize a PLII file as surround, because it really isn't. It's a stereo stream, and the receiver takes audio that sounds like it should be surround (it sounds muffled), and throws it in the back.

That's not strictly true.

Pro Logic signals do indeed have multiple channels encoded into them at source. It uses phased signals to embed the 2 extra channels within the regular stereo signal. Whilst not as precise as discrete channels, the author still has a certain amount of control over sound positioning in a PLII signal.

For example, (if you've got one), start the Software Update process on a Nintendo Wii. Even with just PLII support, you'll notice the 'connecting' sound sweeps around the listener -- it doesn't just get the muffled bits plonked at the rear.

bentoms
Dec 11, 2007, 07:29 AM
I am getting meself an Apple TV for chrimbo, I've waited a while but have relised now that the limitations of my setup actually allow for the apple tv to plug in quite happily!

Limitations are:

My TV is 720p only.
My surround sound system can take DPLII from RCA, & it does this for my Wii.


Being that I have ordered the 80 GB version as I have some 30gb of music & pictures to copy. The only video i'll play through are stuff like prison break etc.. which i download as I cannot afford sky (or the p*ss poor internet connection that i will get, (125k if lucky as am 2.5km from exchange!)).

(Don't worry though as anything that i download i then buy once the dvd boxset is released, it clears my concious anyways!).

So all i need now in a HD Component switch box & i am away!

imlucid
Dec 11, 2007, 11:06 AM
Being that I have ordered the 80 GB version

I hope that was a typo since there are only 40 and 160 GB versions available from Apple...

Kevin

Cave Man
Dec 11, 2007, 03:35 PM
"make sure your ATV is connected to a DPLII-capable receiver" Therein lies the problem.

Many Amps don't support this and I for one and not going to change my $2000 Amp because Apple has decided NOT to follow convention and use a commonly used format. When will they learn???

I don't know how many amps/receiver support it, but I suspect it's the great majority of those sold today. I just checked Onkyo's and Yamaha's web sites and all of their home theater receivers do DTS, Dolby Digital and Dolby Pro Logic I and II.

Apple has created many duds by using non popular, or close source standards. Just look at M$ and how unpopular they've become with their closed standards. Remember how expensive peripherals used to be for the mac before they embraced USB? I know ACC is not the same as open or closed source, but the point I'm trying to make is; Apple stuffed up by not following convention with the Apple TVs audio. They used all the right connectors but they didn't get the internals right.

I think it's more complex than this. There is no content from iTMS that is encoded in 5.1 (DTS or DD), thus they don't have the impetus to do it. Adding to this is the almost certain fact that they (or the studios) will have to license DD or DTS audio for iTMS movies/shows. This will undoubtedly add to the cost of the files. Then they would have to add support to Back Row to passthrough the encoded DD or DTS out the optical port to a receiver capable of decoding DD or DTS for 5.1 surround sound. We are all hopeful that this is coming - perhaps at MW in January.

I think it's sad that Apple didn't simply make this product with the same audio support as a $50 DVD player :(

Yes, it would have been nice if Apple had put 6 audio-out ports for the 5.1 (hell, why not 8? The chip will decode it), but there wasn't any content to permit it. Let's hope something like this eventually comes to fruition - both optical port for passthrough of DD/DTS and discrete output for decoding AAC 6-channel. But the receiver will have to have inputs for these as well. It would be cheapest (for Apple, anyway) to do the decoding in the ATV and have the 6 discrete outputs because then they wouldn't have to license DD or DTS - they could just encode using their existing Quicktime technology (6-channel AAC).

Cave Man
Dec 13, 2007, 05:39 PM
I've updated the first post with info about VLC, DTOX and MTR for Mac-based home theaters.

Avatar74
Dec 14, 2007, 03:27 PM
I've noticed some folks are confused about why Dolby Digital is not supported but surround sound seems to be coming from the track if they switch to Dolby ProLogic II mode on their receiver. I think this warrants a brief explanation for those interested...

Prior to the creation of Dolby Digital (AC-3) 5.1 channel surround, Dolby Surround was the prevailing format for theatrical surround. Dolby Surround is an analog matrix. I'll get to what that means in a second...

A digital format like AAC is designed to reconstruct an analog signal. Most films that have been encoded as Dolby Digital by the studio also have, for older sound systems, Dolby Surround analog encoding. This means that in addition to the 6 discrete channels of digital information, the surround channels have been embedded in the analog signal of the front left and right channels to be decoded by a Pro Logic decoder.

A moment to explain what matrix encoding actually is...

In the digital world, separate bitstreams can be muxed (multiplexed) into one bitstream of digital data and then demuxed as discrete channels. But in the analog world, the Dolby Labs folks, and others, came across a rather ingenious way to do the same thing with analog signals.

I know this will sound elementary but I want to reinforce the idea here because I don't think it's often really understood what the difference is: A digital signal uses multiple "bits" (binary digits, e.g. 0 or 1) per sample to reconstruct the frequency and amplitude of the source at any given interval. An analog signal directly uses voltage oscillations to represent a signal identical to the source. My reason for repeating this distinction here is to emphasize that one format has to reconstruct the signal from an entirely different storage methodology (pulses of electricity, light or whatever else can be used to burst data), the other format (analog) doesn't need to reconstruct the signal... it IS the signal.

The left and right surround channels are phase-shifted 90 degrees and combined with the left and right front channels. So when the recording is played back on any normal system, only the in-phase signal is heard. But in a ProLogic decoder, the out of phase signal is extracted and sent to the surround channels.

I discovered for myself when purchasing the works of Isao Tomita, one of the early synthesizer pioneers who used Dolby Surround in his sound recordings, that the iTunes versions of these songs had been encoded straight from his Dolby Surround masters. The digital files reconstructed the original analog source which was decodable by my Dolby Digital processor (all Dolby Digital processors by default have the ability to decode Dolby Surround analog in a ProLogic mode).

So what you're experiencing can be one of two things... If no surround matrix is present, the decoder is taking any out of phase information and sending it to the surrounds. This has an unpredictable, muddy effect. If you can distinctly hear surround but not quite as clearly as Dolby Digital, and you're watching a movie, then chances are the Dolby Surround analog mix was encoded into the AAC and reconstructed upon playback.

You'll also find that virtual surround encoding methods such as Qsound are perfectly realizable through a system like AppleTV because they are analog methodologies... except virtual surround methods do not require decoding because they rely on perceptible phase shifts of stereo signals to create illusions of spatial characteristics.

wmealer
Dec 14, 2007, 05:09 PM
All this talk about surround sound from the audiophiles...

Don't get me wrong, I'm all for Apple adding as many features to this magical little box as possible. But I can't help but keep my feet planted firmly in reality. We all know Apple has already called this project a "hobby." Do we really expect them to try to compete in the higher-end home theater market with a hobby?

Apple is all about appealing to the masses, not to the niche markets who know the difference between Dolby TrueHD, DTS, THX, DD, PLII, and so on. They are more concerned that :apple:tv works in as many homes as possible (with as little fuss as possible), than pleasing those of us who want the best home theater experience possible. That's a lot to ask from this tiny silver box in my entertainment armoire, which even has trouble streaming low-level 720p content without some sort of hiccup.

Cave Man
Dec 14, 2007, 09:00 PM
I discovered for myself when purchasing the works of Isao Tomita, one of the early synthesizer pioneers who used Dolby Surround in his sound recordings, that the iTunes versions of these songs had been encoded straight from his Dolby Surround masters. The digital files reconstructed the original analog source which was decodable by my Dolby Digital processor (all Dolby Digital processors by default have the ability to decode Dolby Surround analog in a ProLogic mode).

Wow, that's very interesting. Can you recommend half a dozen songs from him that are encoded in such a way and also available on iTMS? I'd like to download a few and give them a try.

I also understand that Pink Floyd'd Dark Side of the Moon was recorded in quadrophonic. Have you heard if it's made its way to DPLII? That would be completely cool (or better yet, 5.1 DD).

diamond.g
Dec 14, 2007, 10:17 PM
Encoding DTS/DD in software is incredibly expensive, I would be impressed if Apple went that route.

I don't think downloading multi gig files is that much of an issue, if the ATV were to allow purchasing of the content from it and allowed streaming of partially downloaded files (think 360). Batman Begins on Xbox Live in HD is 5 or 6 gig, which is easily downloaded overnight. I am sure Apple has the resources to ensure optimum speeds are achieved.

Cave Man
Dec 15, 2007, 02:59 PM
Encoding DTS/DD in software is incredibly expensive, I would be impressed if Apple went that route.

I'm sure that'll increase the cost of downloads from iTMS; if they ever show up.

Batman Begins on Xbox Live in HD is 5 or 6 gig, which is easily downloaded overnight. I am sure Apple has the resources to ensure optimum speeds are achieved.

That's very encouraging. Is this 720 with DD, DTS or some other true 5.1 audio? I did my calculations based solely on ratios of AC-3 to stereo DPLII and DVD-quality to 720 video. I didn't consider frame or bit rates at all. Let's hope Apple can (and will) do something similar and keep that file size down to 5 or 6 gigs - that would be very manageable.

diamond.g
Dec 15, 2007, 03:47 PM
I'm sure that'll increase the cost of downloads from iTMS; if they ever show up.



That's very encouraging. Is this 720 with DD, DTS or some other true 5.1 audio? I did my calculations based solely on ratios of AC-3 to stereo DPLII and DVD-quality to 720 video. I didn't consider frame or bit rates at all. Let's hope Apple can (and will) do something similar and keep that file size down to 5 or 6 gigs - that would be very manageable.

Oddly, I just looked on live and can't seem to find Batman Begins or Superman Returns. I found TMNT and it is 720p with 5.1 audio and it is only 4GB. Meet the Robinsons is only 4.3GB. 300 is 5.3 GB.

I just figured out why I can't find the other two, it looks like MS rotates movies. Movies seem to be available for a certain period of time. That could be another place Apple could do better.

Cave Man
Dec 15, 2007, 04:29 PM
Oddly, I just looked on live and can't seem to find Batman Begins or Superman Returns. I found TMNT and it is 720p with 5.1 audio and it is only 4GB. Meet the Robinsons is only 4.3GB. 300 is 5.3 GB.

That's excellent news. What is the audio codec for your 5.1 - DD or DTS (or something else)? Meet the Robinsons from iTMS (640x360, stereo, subtitles) is 1.09 gigs, so if Apple can get DD or DTS issues resolved, it looks like we could get 720 HD/5.1 surround movies at a reasonable size.

diamond.g
Dec 15, 2007, 05:33 PM
That's excellent news. What is the audio codec for your 5.1 - DD or DTS (or something else)? Meet the Robinsons from iTMS (640x360, stereo, subtitles) is 1.09 gigs, so if Apple can get DD or DTS issues resolved, it looks like we could get 720 HD/5.1 surround movies at a reasonable size.

Pretty sure it is DD.

Cave Man
Dec 15, 2007, 09:45 PM
Pretty sure it is DD.

Does the DD indicator illuminate on your receiver when you play the movies? My Onkyo has DD, DTS, Neo and PLII indicators - that's how I know the files are being passthrough'd to the receiver. If your DD illuminates, you'd know for certain.

diamond.g
Dec 16, 2007, 03:14 PM
Does the DD indicator illuminate on your receiver when you play the movies? My Onkyo has DD, DTS, Neo and PLII indicators - that's how I know the files are being passthrough'd to the receiver. If your DD illuminates, you'd know for certain.

Sadly I am have not downloaded any of the movies. The HD ones are 480 points which is around 5 dollars. MS claims the files to have 5.1 Digital Audio. I would be inclined to think it is DD, but it is hard to say cause the 360 can encode DD or DTS.

Cave Man
Dec 16, 2007, 03:44 PM
Sadly I am have not downloaded any of the movies. The HD ones are 480 points which is around 5 dollars. MS claims the files to have 5.1 Digital Audio. I would be inclined to think it is DD, but it is hard to say cause the 360 can encode DD or DTS.

Hmm, I wonder, then if it's some other format. Does the Xbox 360 have its own amplifier? If so, then this makes sense. If it doesn't that would imply that it is decoding the 6 discrete channels that would need to be sent to a receiver/amp that has 6 inputs for these channels. Time for Google...

OK, here it is:

http://www.dolby.com/consumer/games/yourconsole.html

Looks like the Xbox takes a Toslink cable to a receiver to get Dolby Digital 5.1. So, it should work so long as the video is encoded with DD. It'd be nice if you could somehow determine that. Sounds like 5 or 6 gigs may be a realistic expectation after all (fingers crossed).

Cave Man
Dec 26, 2007, 09:28 PM
Well, it looks like there will be some movie activity at MacWorld, provided the rumor is correct. Let's hope Apple introduces DD or DTS passthrough to Quicktime, both for Macs and Apple TV. Add a little HD video and all would be good...

tronic72
Dec 27, 2007, 09:18 AM
Well, it looks like there will be some movie activity at MacWorld, provided the rumor is correct. Let's hope Apple introduces DD or DTS passthrough to Quicktime, both for Macs and Apple TV. Add a little HD video and all would be good...

I second that Caveman. Finger Crossed!!!

Cave Man
Jan 13, 2008, 03:15 PM
I've done a bit more digging and there is a way to get Front Row on a Mac to do Dolby Digital AC-3 5.1 surround passthrough, at least with Leopard. It requires that you do the following:

1. Use Handbrake to encode your DVD as an AVI (MPEG-4 with AC-3 passthrough) file. You then open the file with QuickTime Pro (http://store.apple.com/1-800-MY-APPLE/WebObjects/AppleStore.woa/wa/RSLID?mco=DD566660&fnode=home/shop_mac/software/apple&nplm=D3380Z/A) and then save as a self-contained movie. This movie can then be dropped into iTunes, making it available to the Mac through Front Row. However, it does not show up on the ATV since it is an incompatible file type (even though it's a QuickTime movie). I did this with the first Spiderman movie and it was compressed at 2500 bit rate with AC-3 5.1 DD to a final size of 2.5 gb.

2. Follow the directions here (http://geekwithfamily.com/2007/07/05/home-theater/howto-5-easy-steps-to-output-dolby-digital-from-quicktime-player/) to install Perian, configure Audio Midi Setup to digital output, then a modification of the com.cod3r.a52codec.plist file using Property List Editor (part of Apple's development package (http://developer.apple.com/) and a free download).

Once these are done, both QuickTime stand-alone and Front Row (through QuickTime) play the movie file with Dolby Digital 5.1 passthrough to a receiver via the optical port (of course, the receiver must be able to decode Dolby Digital). Installation of Perian and the com.cod3r.a52codec.plist file on an ATV's hard drive would be simple enough (just by pulling the hard drive and connecting it to an Intel-based Mac using USB, or by AFP if the hack is in place). But would Perian allow the movie file to show up on the Apple TV?

Also, the Audio Midi change is something I have no idea about. When I set these settings on my Mini, ~Library/Preferences/com.apple.audio.SystemSettings.plist was the only file that I can readily see was modified (by sorting files by date modified). I do not know if there are invisible files that might have also been modified. It may be that this file could be copied straight over to the ATV hard drive as well, thus completing the activation of AC-3 Dolby Digital passthrough on the Apple TV. I won't be exploring this further until after Tuesday's show, but thought I'd share this info (which may already be known by others). If you have Perian installed on your ATV and have AFP access, it might be worth a try to see if it works.

Superman07
Jan 15, 2008, 05:49 PM
So, long story short, it looks like this problem is now solved based on today's annoucnements. Am I jumping to conclusions? Understand that it's only DD, and not DTS, etc.

Duffinator
Jan 15, 2008, 06:56 PM
So, long story short, it looks like this problem is now solved based on today's annoucnements. Am I jumping to conclusions? Understand that it's only DD, and not DTS, etc.At least a step in the right direction. It looks like only HD rental movies will be DD. Not sure why regular DVD's will not be DD since they are on disc. Can anybody confirm this?

imlucid
Jan 15, 2008, 07:11 PM
At least a step in the right direction. It looks like only HD rental movies will be DD. Not sure why regular DVD's will not be DD since they are on disc. Can anybody confirm this?

Regular DVDs are on disc? I'm not sure what you are saying. There is no disk in the iTunes Rental scheme... (other than your hard drive).

Kevin

Duffinator
Jan 15, 2008, 07:19 PM
Regular DVDs are on disc? I'm not sure what you are saying. There is no disk in the iTunes Rental scheme... (other than your hard drive).

KevinMovies on regular DVD's have DD but non HD movies on iTunes don't have a DD soundtrack. At least that's how I read it.:confused:

Superman07
Jan 15, 2008, 07:21 PM
Right, but my point was that if you use 5.1 through various programs, the ATV will now be able to output, whereas before it could not!

Cave Man
Jan 15, 2008, 07:28 PM
Right, but my point was that if you use 5.1 through various programs, the ATV will now be able to output, whereas before it could not!

It looks like the ATV will do 5.1 output with media encoded in Dolby Digital. The caveat will be whether the ATV will accept all media that can be encoded in Dolby Digital.

Cave Man
Jan 15, 2008, 08:03 PM
The Quicktime update now plays the AC-3 chatter over the speakers, from both .mov and .avi files. I think before it would only play back the video and give an error about an unsupported type (presumably, the audio). Can someone confirm that QT 7.4 will now passthrough AC-3 audio to their receiver by optical cable for 5.1 surround sound playback? If so, does it work with both .avi and .mov files? (I've not updated my home theater Mac Mini yet until I'm sure nothing will be broken. Otherwise, I would do this test myself.)

Duffinator
Jan 15, 2008, 08:18 PM
Right, but my point was that if you use 5.1 through various programs, the ATV will now be able to output, whereas before it could not!Understood.

mtbdudex
Jan 16, 2008, 06:05 AM
I hate posting similiar question in two places, but did not see this thread on the ATV surround sound.
http://forums.macrumors.com/showthread.php?t=415346

I define HD content = HD video + HD audio, plain and simple.

For "true" HD content Apple should at least use one of the higher quality surround sound formats, like the HD lossy formats DD+ or DTS HD High Resolution audio.

I'm guessing the lossless Dolby TrueHD/DTS-HD Master Audio takes up too much bandwidth.

I will NOT forgo HD audio, true Home Theatre/Cinema experience includes both HD video AND HD audio, DD 5.1 while good should not be the std for Apple TV HD downloads.

More and more receivers have the DD+ capability, you can really hear the difference over DD 5.1.

imlucid
Jan 16, 2008, 10:59 AM
I hate posting similiar question in two places, but did not see this thread on the ATV surround sound.
http://forums.macrumors.com/showthread.php?t=415346

I define HD content = HD video + HD audio, plain and simple.


Then according to your definition, ATV does not support "HD content", nor can you get it from the iTunes Store.

However, I think that most people are going to be very happy with Apple's HD rentals. 720p and 5.1 are a big step up.

Kevin

mtbdudex
Jan 16, 2008, 12:24 PM
Then according to your definition, ATV does not support "HD content", nor can you get it from the iTunes Store.

However, I think that most people are going to be very happy with Apple's HD rentals. 720p and 5.1 are a big step up.

Kevin

I'd be curious why they can't go DD+ for "true HD", is it a technical issue?
(need new decoder chip in ATV) Bandwidth issue? (too large file size)?
Political issue? (studios don't want people to have DD+ for fear of copy/dist)

Avatar74
Jan 16, 2008, 01:02 PM
I'd be curious why they can't go DD+ for "true HD", is it a technical issue?
(need new decoder chip in ATV) Bandwidth issue? (too large file size)?
Political issue? (studios don't want people to have DD+ for fear of copy/dist)

Dolby Digital Plus or Dolby TrueHD is as much a technical issue as it is an investment issue.

The vast majority of people do not have Dolby TrueHD or Dolby Digital Plus decoding hardware. But the adoption rate of Dolby Digital AC-3 5.1-channel surround has grown considerably.

Dolby Digital Plus is really a theatrical application, IMO... where an auditorium of large scale is going to take advantage of the additional channels and fidelity. Dolby TrueHD is a consequence of greater storage but, realistically, I don't think that the average viewer will know the difference.

Hell, half the people who insist on Dolby Digital fail to realize that it in and of itself is a highly compressed format (448Kbps for 5.1 on DVD, and 320Kbps for 5.1 theatrical)... but this is because, as a perceptual coding schema, it is acoustically transparent to the uncompressed source by and large... .especially true in the home application where metadata parameters further squeeze greater performance out of the dynamic range of Dolby Digital.

I do believe that, also, a different chipset is required than the one in the AppleTV.

I think a better solution would be Dolby Digital Live, whereby multichannel sources could be transcoded on the fly to AC-3, but AC-3 passthrough is equally sufficient when all the source content has an AC-3 passthrough track embedded in the file... and since 1992 Dolby Digital has withstood the test of time despite all that the uneducated audiophile (read: layman listeners with no real engineering background) has to say about it.

Avatar74
Jan 16, 2008, 01:13 PM
Movies on regular DVD's have DD but non HD movies on iTunes don't have a DD soundtrack. At least that's how I read it.:confused:

This is correct, for now. It could change. I'm not quite sure what the issue is... could be technical, could be negotiations-related, could be product differentiation so they can sell more HD rentals.

Actually, now that I think about it... here's your answer... The iPods and iPhone may not have the hardware/software to decode Dolby Digital AC-3 bitstreams or the bitstream is too large. It doesn't matter if the software can "unpack" the passthrough AC-3 from the H.264 file... you've still got two problems:

a) iPod/iPhone does not have a hardware/software AC-3 decoder, and such software would require a license in every instance making iPods and iPhones more expensive than they are now.

b) The bigger problem is that the audio chipset in the iPods and iPhone appear to be designed to process 320Kbps AAC at most. 5.1 AC-3 however, is 448Kbps from a DVD.

This makes it complicated, and unnecessarily so, for one standard definition file to be entirely mobile... for now.

Again, future iterations could change this, but you're also going to run into greater storage requirements, greater licensing requirements, greater processing requirements, etc. raising the cost on it. Be prepared for that.

Frankly, I don't see that as nearly as big a deal since... if you don't have an AppleTV, Dolby Digital isn't going to be of as much use to you since you won't be carrying a 5.1 surround system with you wherever you go, and if you DO have an AppleTV, you probably have a High Definition TV, and can rent HD rentals instead of the SD ones.

Duffinator
Jan 16, 2008, 01:14 PM
Dolby Digital Plus or Dolby TrueHD is as much a technical issue as it is an investment issue.

The vast majority of people do not have Dolby TrueHD or Dolby Digital Plus decoding hardware. But the adoption rate of Dolby Digital AC-3 5.1-channel surround has grown considerably.

Dolby Digital Plus is really a theatrical application, IMO... where an auditorium of large scale is going to take advantage of the additional channels and fidelity. Dolby TrueHD is a consequence of greater storage but, realistically, I don't think that the average viewer will know the difference.

Hell, half the people who insist on Dolby Digital fail to realize that it in and of itself is a highly compressed format (448Kbps for 5.1 on DVD, and 320Kbps for 5.1 theatrical)... but this is because, as a perceptual coding schema, it is acoustically transparent to the uncompressed source by and large... .especially true in the home application where metadata parameters further squeeze greater performance out of the dynamic range of Dolby Digital.

I do believe that, also, a different chipset is required than the one in the AppleTV.

I think a better solution would be Dolby Digital Live, whereby multichannel sources could be transcoded on the fly to AC-3, but AC-3 passthrough is equally sufficient when all the source content has an AC-3 passthrough track embedded in the file... and since 1992 Dolby Digital has withstood the test of time despite all that the uneducated audiophile (read: layman listeners with no real engineering background) has to say about it.This is all fine but when it comes to renting movies in one of the HD formats both HD and BD use DD HD and DTS HD. So for iTunes to be competitive I would hope they would include the formats sometime in the future as a pass through.

Avatar74
Jan 16, 2008, 01:18 PM
This is all fine but when it comes to renting movies in one of the HD formats both HD and BD use DD HD and DTS HD. So for iTunes to be competitive I would hope they would include the formats sometime in the future as a pass through.

Why? Do you have a DTS-HD processor or a Dolby Digital TrueHD processor?

Do you know anyone who does?

How many of the people who have BluRay or HD DVD have a DTS-HD or Dolby Digital HD processor? Mind you if they have only DTS-ES or Dolby Digital EX it's just going to play the compressed track... not the uncompressed one.

Being competitive is not about having every feature under the sun... it's about having the features that people will actually pay for. Which is often different from what they say they will pay for. This is why Apple is smarter to deploy things in a tiered strategy and use actual sales data, not just marketing survey data, to dictate the direction of their future products. People often say one thing and settle for another. Companies that bank blindly on what people say and not what they do can go bankrupy very, very quickly.

There's a reason Apple has $15 billion in cash and zero debt... and thanks to that, they'll be around to make AND support that revision 2 or 3 or 4 that you are looking for, rather than starting with 4, going bankrupt and then having to close shop rendering your investment worthless. Many a startup has gone out precisely in this manner... perhaps you've heard of a few?

jbrjake
Jan 16, 2008, 01:19 PM
By 'encoding' into PLII, all you're doing is ripping the 5.1 track as stereo, and letting the decoder use algorithms to put audio that sounds like it should be in the back in the back, and sounds that are the same in both speakers (like voice tracks) into the center channel.
Simply no.

First of all, PLII supports 5.1 channel matrixed sound. You seem to be confusing it with PLI, which only had stereo and a center channel.

Second, encoding to PL2 is *not* just ripping the track as stereo. It involved decoding all 6 channels and applying phasing to the surround channels so they can be merged with the stereo channels.

I can prove it. With math:
http://trac.handbrake.fr/browser/trunk/contrib/patch-a52dec.patch?rev=483

Avatar74
Jan 16, 2008, 01:42 PM
Simply no.

First of all, PLII supports 5.1 channel matrixed sound. You seem to be confusing it with PLI, which only had stereo and a center channel.

Second, encoding to PL2 is *not* just ripping the track as stereo. It involved decoding all 6 channels and applying phasing to the surround channels so they can be merged with the stereo channels.

More specifically, for those who are bored/geek enough to take interest... ProLogic II is not technically a format. It is an encoding/decoding algorithm. The format in question is, often, Dolby Surround analog. More recent programs, specifically games, have been encoded in Dolby ProLogic II or IIx specifically... but all movies in an analog Dolby surround format are generally Dolby Surround analog to begin with. Dolby Digital soundtracks contain a Dolby Surround analog matrix embedded in the L-R channels for home systems that are ProLogic I/II only.

In the transcoding process, a Dolby Digital AC-3 5.1-channel bitstream is demultiplexed into five discrete full range channels, and one LFE channel. These are L,C,R,SurL,SurR, and LFE.

While Dolby ProLogic II intelligently places center dialogue and LFE by way of filters, the SurL and SurR channels are stereo matrixed into the front L and R channels by way of shifting their signals 90 degrees out of phase with the L and R.

The ProLogic II decoder samples the audio and extracts the portion of the signal at 90 degrees off axis from phase and sends these to the SurL and SurR channels. If the source was Dolby Surround analog, and only one mono surround channel existed, then the SurL and SurR output will be 2-speaker mono. If the source was Dolby Digital, however, Dolby Surround and Dolby Digital encoding hardware/software matrixes the SurL to the L channel, and the SurR to the R channel.. .so the demuxed output is identical to the 5.1 Dolby Digital surround.

A bandpass filter sends frequencies below 120Hz to the LFE. Another filter removes dialogue by... if I recall correctly, a bandpass filter that covers the range of normal human dialogue, particularly if it's centered in the stereophonic image of the playback.

The LFE is not tricky, because if the source was a Dolby Digital soundtrack to begin with, and this will surprise some audio snobs who insist that LFE crossovers be set to 80Hz... Dolby Digital licensed encoding hardware/software applies a bandpass filter at 120Hz to remove all frequencies below 120Hz from the mains and encode them in the LFE channel only. This is by default, but on occasion engineers can set it manually... THX engineers tend to set the LFE low-pass at 80Hz. This is hard encoded in the mastering stage, not applied by the Dolby Digital processor/decoder. Thus, the processor doesn't have to do any "guessing" as to what to send to the LFE on your 5.1 surround system, the cutoff is in the bitstream of the source. Now, this is assuming the source was a Dolby Digital soundtrack. But if the source was a Dolby Surround analog soundtrack, no LFE channel actually existed and the bandpass is applied across the board... i.e. across all full-range channels, and the results sent to the LFE output.

So what does all this mean... It means that the proper Dolby Digital or ProLogic II decoding hardware can do a very good job of discretely extracting 5.1 channels of surround from a Dolby Surround analog mix.

Granted, it will not always sound identical to a Dolby Digital mix, but that depends on more than just one being digital vs. one being analog. It depends more so on how discrete the channels were to begin with (I've heard some DD mixes worse than some Dolby Surround mixes), the quality of the overall mastering of the source (garbage in, garbage out), the quality of the decoder (and whether or not it is a LICENSED decoder), the quality of the speakers, etc.

Keep in mind that Dolby Digital is also a multiplexed format... there aren't five separate bitstreams in an AC-3 file... but digital demultiplexing (at a low cost factor) can be more discerning because frequencies in each channel are reconstructed from packets of data instead of complex frequencies.

HOWEVER, the quality of analog multiplexing can surpass digital multiplexing... but it depends on the quality of the hardware and software in use. Vinyl doesn't win over CD's, though, because at low cost, digital encoding is more efficient at error-free reproduction -- there digital wins out. Vinyl is a very, very dirt cheap storage and reproduction medium. It takes tremendously expensive technology to surpass digital multiplexing in the analog world... and I don't mean a $20,000 turntable. I mean entirely different technology like Dense Wavelength Division Multiplexing (DWDM) which can combine 80-100 wavelengths of light into one waveform that can transmit more than the per second traffic of the entire internet in 1997.

mtbdudex
Jan 16, 2008, 06:09 PM
Why? Do you have a DTS-HD processor or a Dolby Digital TrueHD processor?

Do you know anyone who does?

How many of the people who have BluRay or HD DVD have a DTS-HD or Dolby Digital HD processor? Mind you if they have only DTS-ES or Dolby Digital EX it's just going to play the compressed track... not the uncompressed one.

Being competitive is not about having every feature under the sun... it's about having the features that people will actually pay for. Which is often different from what they say they will pay for. This is why Apple is smarter to deploy things in a tiered strategy and use actual sales data, not just marketing survey data, to dictate the direction of their future products. People often say one thing and settle for another. Companies that bank blindly on what people say and not what they do can go bankrupy very, very quickly.

There's a reason Apple has $15 billion in cash and zero debt... and thanks to that, they'll be around to make AND support that revision 2 or 3 or 4 that you are looking for, rather than starting with 4, going bankrupt and then having to close shop rendering your investment worthless. Many a startup has gone out precisely in this manner... perhaps you've heard of a few?

Avatar74 ;
I respect everything you've said in thhis thread, great points and well thought out.

And yes, Apple is extremely good at matching the "real" consumer needs at price point they will pay vs packing all the "perceived needs" into devices.

With that said, I have just bought the newly released Denon AVR-4308CI for my basement Home Cinema - which has all the lossless HD audio formats, until 2 weeks ago I had "just" DD 5.1/DTS in my 7 year old Onkyo 787, which is still a decent A/V unit.
My right now basement project can be seen here:
http://forums.macrumors.com/showpost.php?p=4763565&postcount=198

Duffinator
Jan 16, 2008, 09:48 PM
Why? Do you have a DTS-HD processor or a Dolby Digital TrueHD processor?

Do you know anyone who does?Does it matter? If I'm paying $4.99 for a HD rental is it reasonable for me to expect that it's the same quality as the HD/BD DVD that I can rent for less??? I'm sure Apple will get the audio formats sorted out eventually.

I have a Denon 3808CI, look up the specs if you want to know.

Avatar74
Jan 17, 2008, 09:48 AM
Does it matter? If I'm paying $4.99 for a HD rental is it reasonable for me to expect that it's the same quality as the HD/BD DVD that I can rent for less??? I'm sure Apple will get the audio formats sorted out eventually.

I have a Denon 3808CI, look up the specs if you want to know.

Duffinator, with all due respect...

Your original question addressed, specifically, "in order for Apple to be competitive"... not "in order for Apple to cater to my personal needs which happen to be an exception to the rule."

I'm disappointed that there aren't more 24-bit Linear PCM systems out there to suit the music that I compose, record, produce, mix and master.

That being said, I realize that I am also an exception to the rule... so what I take issue with is not your concern about fidelity. I take issue simply with the phrasing of your statement with which I simply disagree. Apple is not being uncompetitive at this stage by not supporting Dolby TrueHD.

The adoption rates of HDTV sets are higher than the adoption rates of HD surround systems at this stage in the game and will probably remain so for a few years.

However, ten years from now that statement might be more accurate... even though I will disagree with you from a technical standpoint as to the usefulness of Dolby TrueHD and Dolby Digital Plus in the home unless you have a private theater the size of main room at a multiplex, with acoustics that meet THX specifications... that is, unless you paid THX $250,000 to design a starter THX-certified home theater that meets all the acoustic room specs.

Avatar74
Jan 17, 2008, 10:06 AM
Avatar74 ;
I respect everything you've said in thhis thread, great points and well thought out.

And yes, Apple is extremely good at matching the "real" consumer needs at price point they will pay vs packing all the "perceived needs" into devices.

With that said, I have just bought the newly released Denon AVR-4308CI for my basement Home Cinema - which has all the lossless HD audio formats, until 2 weeks ago I had "just" DD 5.1/DTS in my 7 year old Onkyo 787, which is still a decent A/V unit.
My right now basement project can be seen here:
http://forums.macrumors.com/showpost.php?p=4763565&postcount=198

That's great that you take an interest in home theater. Paradigm's a good set of speakers for the price, btw.

I'm curious... what are you planning to use for the screen? It appears from your notes on the image you are doing front projection because you're cutting a screen to 2.35:1.*

It doesn't appear you have enough room for 100" HD projection (my uncle had 9 feet, but needed 18, for a Barco cinema HD projector... so his carpenters built a reflector frame in the rear projection room!)... Are you planning to go LCD or plasma? My suggestion would have been a recessed wall for an LCOS display... nothing beats LCOS for the 3 C's except a Trinitron XBR cathode ray tube.

* Cut that screen wider. The actual aspect ratio of Panavision (http://www.panavision.com/aspect_ratio.php) (mistakenly called "scope" as a reference to now defunct CinemaScope) is 2.40:1, not 2.35:1.... Yes, I know the DVD's all say the latter but they're referring to the cropped image with safe lines. You can have black curtains to matte accordingly, but in order to actually project the entire image, TV-safe areas and all, the screen itself has to be 2.40:1. Of course if you're watching HDTV programming it doesn't matter because most of it, much to my chagrin, is still blocked for 4:3 anyway. I had a big discussion with the exec producer of Comanche Moon (CBS) over this just yesterday.

Duffinator
Jan 17, 2008, 10:20 AM
Duffinator, with all due respect...

Your original question addressed, specifically, "in order for Apple to be competitive"... not "in order for Apple to cater to my personal needs which happen to be an exception to the rule."OK so I'm an exception to the rule and being selfish here. :rolleyes:

Then how does Apple justify the non HD downloads not having DD soundtracks? It just seems that Apple is missing the mark here. I have no doubt that in a few years downloading movies will be the dominate way we all watch movies and I look forward to it. But if Apple is developing this business model for people to watch on their TV's via ATV they need to provide the DD soundtrack and pro-logic is not even close to DD. Like I said I'm sure they will get this worked out but not including DD is a big miss in my book. I wonder how NetFlix is handling soundtracks on their download service?

NightStorm
Jan 17, 2008, 10:30 AM
OK so I'm an exception to the rule and being selfish here. :rolleyes:

Then how does Apple justify the non HD downloads not having DD soundtracks? It just seems that Apple is missing the mark here. I have no doubt that in a few years downloading movies will be the dominate way we all watch movies and I look forward to it. But if Apple is developing this business model for people to watch on their TV's via ATV they need to provide the DD soundtrack and pro-logic is not even close to DD. Like I said I'm sure they will get this worked out but not including DD is a big miss in my book. I wonder how NetFlix is handling soundtracks on their download service?
I think it is simply because they do not have a way of making DD soundtracks work with iPods/iPhones (yet?), therefore they'd have to have yet another version of the same movie on a server somewhere.

Avatar74
Jan 17, 2008, 10:50 AM
I think it is simply because they do not have a way of making DD soundtracks work with iPods/iPhones (yet?), therefore they'd have to have yet another version of the same movie on a server somewhere.

Correct. I mentioned this somewhere earlier but the conclusion I came to was that Dolby Digital pass-through will not work with iPods, iPhones and iTunes playback at present.

In order for this to change, a hardware or software decoder must be licensed from Dolby Laboratories by Apple... extra cost not yet factored in to the price of these products/services. That may change in future iterations.

The reason this matters, to answer duffinator's question, is because Apple's research probably shows them that there are two categories of users interested in the service:

1. Home theater enthusiasts - Have AppleTV, have HDTV, have surround system... far more likely to rent HD releases than their SD counterparts. Convenience takes a backseat to fidelity for this crowd. They spend more, configure more, because they want more fidelity.

2. Casual moviegoers - Mostly don't have AppleTV, maybe/maybe not surround system, but a Mac or PC and probably an iPod, and want, more than anything, convenience. They spend less, want to configure less... they just want it to work.

Category 1 is who the HD releases target.

Category 2 is who the SD releases target.

Consequently, the SD releases cannot have Dolby Digital pass-through just yet because the file they want needs to work on all the different pieces of the iTunes ecosystem.

The two categories will never converge because as Dolby Digital and HD become standard, the AV snobs, pardon me, home theater enthusiasts, will want to set themselves further apart from the commoners... buying up UHD systems and 24-bit Dolby TrueHD surround, and whatever else the idiots at Stereophile will convince them to buy too early in the game... but again, these are fewer and far between than the masses who have basic HD or SD setups.

But, there will be some phase-in for the middle folks to start snatching up the higher end systems as they come down in price and rise in supply. This middle group is where Apple's biggest margins tend to be. They straddle the line between fidelity and convenience... watching movies on an iPod is perfectly acceptable to them on the road, and Dolby Digital is good enough for their ears (even though it's a highly compressed perceptual coding schema bested by its descendant, AAC which even the audio snobs pass off as undesirable simply because there are rarer, pricier formats to further distinguish them from the peasantry... when 24-bit becomes standard, they'll want something with bigger bragging rights).

ChargerSteve
Jan 17, 2008, 10:51 AM
Does it matter? If I'm paying $4.99 for a HD rental is it reasonable for me to expect that it's the same quality as the HD/BD DVD that I can rent for less???

When you rent that HD/BD for less, does someone rush to deliver it to your home and put it in your player for you? If so, then you really shouldn't consider the Apple service. If not, it's an Apples to Oranges comparison (pardon the pun).

Also, the AppleTV itself is more than just a movie player. I have not seen anyone ask if it is reasonable to expect their Blue-Ray player to play their picture slideshows, music library, podcasts, You-tube, etc. Afterall, they could get an AppleTV for less than the price of the Blue-ray player and it does all those things...

It is just a different device and service with different features, strengths and weaknesses compared to other devices and services.

Avatar74
Jan 17, 2008, 11:33 AM
It is just a different device and service with different features, strengths and weaknesses compared to other devices and services.

Good point. I haven't seen a convergence device like this, that's this idiotically easy to use. Sure, people talk about XBMC and the like, but they take some work to configure and their interfaces are annoyingly clunky. It's not that I am not technical... but frankly I find it much simpler to leave these things to the geniuses at Apple than setting up my own media library a-la Lucasfilm where I've got a UNIX/IRIX-scripted (Yes, they still use SGI IRIX a lot) server managing terabytes upon terabytes of video.

I like elegant solutions and AppleTV is one... I still think it's missing a few pieces but like every Apple product it's a work in progress that will get tweaked as feedback comes in. That's more than you can say for BluRay, or any Microsoft product... where does consumer consensus ever really figure into their initial design with more priority than vendor demands?

Too many cooks on the wrong side are stirring the broth of those other products... but Apple listens. Look... when people screamed about AppleTV they tweaked it rather than just giving up and inventing some other half-ass product.

Also, AppleTV's functionality is so much software driven that many changes are an update away. Where does BluRay offer this? Where does HD DVD offer this? Where does XBOX 360 offer this (without being a very knowledgeable geek and resorting to all kinds of inelegant hacks)...

There are some serious strengths in the decision to keep the conduit "dumb" and the endpoints smart. By this I mean that the desire to increase the specificity of AppleTV's functions actually decreases its value. To prioritize one function means deprioritizing others. It should be equally capable in serving all media needs... instead of having 12 slots for this card and that card, a tray for this, a button for that, an array of LEDs for everything under the sun and looking like Frankenstein's Walkman. It's got inputs, outputs and a menu... therefore, like the iPhone ostensibly, the interface can be whatever the current application needs it to be, the content can be in whatever format the software updates can decode...

In the very near future, I believe a standard will evolve where all media devices, portable and otherwise, will speak IP and be controllable by devices like AppleTV.

Fixed media are becoming rapidly obsolete... Apple knows this and knows that in 3 years time, AppleTV will need to be evolved enough to take on the onslaught of flexible, wireless nonlinear storage "media players" that will send the optical disk the way of the dodo.

As the authors of worldofends.com (http://www.worldofends.com) point out, the endpoints are where all the value is. The conduit itself needs to be as flexible, as "dumb" as possible to allow all kinds of content through it.

That is the goal of AppleTV and it's long range plan, based on product cycles, patent filings, etc. is clearly to be a two-way interactive conduit that connects ALL your digital lifestyle components... home theater, computer network, mobile digital appliances, etc. Hell, one day you'll be streaming movies to your car's entertainment system via AppleTV over a high speed wireless data network.

The comparison is Apples and oranges? Apples and lemons... if you ask me.

Cave Man
Jan 17, 2008, 12:00 PM
I can easily see Apple being obstinate with DD on the ATV. I think they are going to make the ATV software accept DD from downloads from the Apple servers only. They will keep the prohibition of iTunes streaming or sync a file with AC3 tracks. Thus, even if we can begin to transcode our DVDs to movie MPEG4 files with AC3 (which still remains to be seen), I suspect the ATV will continue to reject them. I hope I'm wrong, but given Apple's recent past, I wouldn't count on it.

diamond.g
Jan 17, 2008, 02:06 PM
I like elegant solutions and AppleTV is one... I still think it's missing a few pieces but like every Apple product it's a work in progress that will get tweaked as feedback comes in. That's more than you can say for BluRay, or any Microsoft product... where does consumer consensus ever really figure into their initial design with more priority than vendor demands?

Too many cooks on the wrong side are stirring the broth of those other products... but Apple listens. Look... when people screamed about AppleTV they tweaked it rather than just giving up and inventing some other half-ass product.

Also, AppleTV's functionality is so much software driven that many changes are an update away. Where does BluRay offer this? Where does HD DVD offer this? Where does XBOX 360 offer this (without being a very knowledgeable geek and resorting to all kinds of inelegant hacks)...
The 360 could be updated to do everything the Apple TV can do. After all the video marketplace is a relatively recent addition.

Duffinator
Jan 17, 2008, 09:56 PM
When you rent that HD/BD for less, does someone rush to deliver it to your home and put it in your player for you? If so, then you really shouldn't consider the Apple service. If not, it's an Apples to Oranges comparison (pardon the pun).

Also, the AppleTV itself is more than just a movie player. I have not seen anyone ask if it is reasonable to expect their Blue-Ray player to play their picture slideshows, music library, podcasts, You-tube, etc. Afterall, they could get an AppleTV for less than the price of the Blue-ray player and it does all those things...

It is just a different device and service with different features, strengths and weaknesses compared to other devices and services.You're points are irrelevant to my arguments. If Apple wants to compete in the marketplace charging fair market prices for video rentals they should deliver what the competition does. Kind of basic business school 101. I bought my ATV without really planning on using it for movie downloads. I use it for streaming photos and music. If Apple gets the movie downloads right I'd be happy to use it and take advantage of the added convenience. I'm not dissing the ATV, I really like it and it's light years ahead of my Hauppauge Media MVP, I'm just not getting too excited about the movie downloads......yet.

Superman07
Jan 18, 2008, 09:26 AM
I can easily see Apple being obstinate with DD on the ATV. I think they are going to make the ATV software accept DD from downloads from the Apple servers only. They will keep the prohibition of iTunes streaming or sync a file with AC3 tracks. Thus, even if we can begin to transcode our DVDs to movie MPEG4 files with AC3 (which still remains to be seen), I suspect the ATV will continue to reject them. I hope I'm wrong, but given Apple's recent past, I wouldn't count on it.

I really really hope you're wrong no your hunch. That is the exact reason I haven't rushed out to buy one before, and the reason I will continue to wait.

Avatar74
Jan 18, 2008, 09:49 AM
The 360 could be updated to do everything the Apple TV can do. After all the video marketplace is a relatively recent addition.

Can a software update:

Fix high hardware failure rates?
Activate 802.11 wireless ethernet (neat trick if there's no wifi card)?
Eliminate the need for a physical fan?
Replace the 20GB drive with a 40, or the 120 with a 160?

Say what you want, but you're comparing entirely different devices.

The AppleTV does not have near the failure rate of the XBOX 360. Also, it is equipped with 802.11b/g/n standard. Also, its design incorporates an aluminum exterior that acts as a baffle to dissipate heat to the outside of the chassis without a fan in the enclosure, which is a great selling point for people who want absolute quiet in their HT setup. Fan noise even at the lowest levels is very noticeable if you have optical audio where the noise floor is inaudible.

Oh... also... can a software update reduce the price of 120GB XBOX 360 Elite from $449 to compete with the 160GB AppleTV ($329)?

Cave Man
Jan 18, 2008, 09:50 AM
I really really hope you're wrong no your hunch. That is the exact reason I haven't rushed out to buy one before, and the reason I will continue to wait.

I hope I'm wrong, too. As I understand it, the MP4 standard (that the ATV plays) does not have a provision for AC3 audio (DD). Thus, Apple will either have to (1) allow the ATV to play other containers (like QT on our Macs already can) or (2) deviate from the MP4 standards. I'm hoping it's just the former - seems to be the path of least resistance (and fewer future problems).

Avatar74
Jan 18, 2008, 09:57 AM
I can easily see Apple being obstinate with DD on the ATV. I think they are going to make the ATV software accept DD from downloads from the Apple servers only. They will keep the prohibition of iTunes streaming or sync a file with AC3 tracks. Thus, even if we can begin to transcode our DVDs to movie MPEG4 files with AC3 (which still remains to be seen), I suspect the ATV will continue to reject them. I hope I'm wrong, but given Apple's recent past, I wouldn't count on it.

This is not the issue. AppleTV isn't "rejecting" anything. It doesn't have the software present in the current iteration to enable Dolby Digital pass through. Even if it has the hardware, software needs to tell the operating system what do to with the pass through embedded in H.264.

I can speak authoritatively on this because I author certified AC-3 content that gets the seal of approval from Dolby Labs directly. I have a license agreement with them.

The real issue as to why there are going to be "restrictions" with Dolby Digital has to do more with the fact that Apple is trying to keep the SD content in one file that can be played on iPod, iPhone, iTunes, and AppleTV.

I hope I'm wrong, too. As I understand it, the MP4 standard (that the ATV plays) does not have a provision for AC3 audio (DD). Thus, Apple will either have to (1) allow the ATV to play other containers (like QT on our Macs already can) or (2) deviate from the MP4 standards. I'm hoping it's just the former - seems to be the path of least resistance (and fewer future problems).

I should clarify my earlier statements about Dolby Digital by pointing out that AppleTV will most likely NOT actually have a Dolby Digital decoder to the best of my knowledge. It doesn't need to.

It will have an updated software that can unpack the AC-3 file from the H.264 bitstream and pass it through to your receiver. Your Dolby Digital RECEIVER (or standalone surround processor, e.g. Dolby DP-564, Lexicon MC-12, etc.) does the actual decoding. That's what pass-through is.

The only reason AppleTV itself would have a Dolby Digital decoder would be if it had six analog outputs to send each channel separately. Otherwise there's no point. The AC-3 bitstream, once unpacked from the H.264 bitstream, will go straight to your receiver over the optical output and be decoded there.

soLoredd
Jan 18, 2008, 10:13 AM
Can a software update:

Fix high hardware failure rates?
Activate 802.11 wireless ethernet (neat trick if there's no wifi card)?
Eliminate the need for a physical fan?
Replace the 20GB drive with a 40, or the 120 with a 160?

Say what you want, but you're comparing entirely different devices.

The AppleTV does not have near the failure rate of the XBOX 360. Also, it is equipped with 802.11b/g/n standard. Also, its design incorporates an aluminum exterior that acts as a baffle to dissipate heat to the outside of the chassis without a fan in the enclosure, which is a great selling point for people who want absolute quiet in their HT setup. Fan noise even at the lowest levels is very noticeable if you have optical audio where the noise floor is inaudible.

Oh... also... can a software update reduce the price of 120GB XBOX 360 Elite from $449 to compete with the 160GB AppleTV ($329)?

Can the :apple:TV play BioShock, Call of Duty 4, or Halo 3?

The comparisons are stupid and you said yourself they are entirely different. But, then you go and list all these comparisons. Brilliant.

What I find major is the lack of DVD player. Say what you want, but having to put my DVDs into my computer, re-encode them, then sync with the :apple:TV sucks for time. One thing the 360 benefits from is the DVD player...I'm not going to buy another version of my movies just so I can watch it on the :apple:TV.

diamond.g
Jan 18, 2008, 10:13 AM
Can a software update:

Fix high hardware failure rates?
Activate 802.11 wireless ethernet (neat trick if there's no wifi card)?
Eliminate the need for a physical fan?
Replace the 20GB drive with a 40, or the 120 with a 160?

Say what you want, but you're comparing entirely different devices.

The AppleTV does not have near the failure rate of the XBOX 360. Also, it is equipped with 802.11b/g/n standard. Also, its design incorporates an aluminum exterior that acts as a baffle to dissipate heat to the outside of the chassis without a fan in the enclosure, which is a great selling point for people who want absolute quiet in their HT setup. Fan noise even at the lowest levels is very noticeable if you have optical audio where the noise floor is inaudible.

Oh... also... can a software update reduce the price of XBOX 360 elite from $449 to compete with the 160GB AppleTV?

So let me get this straight. You talk about features of the AppleTV that are software driven, I say that the 360 can be updated to do the same thing. You then turn around and bring up hardware changes. Please stop moving the goal post.

I know about the 360's hardware failures, I have one. That still doesn't stop MS from adding software features to it. Video Marketplace, Xbox Originals, IPTV (in some places) are things that MS can/did add that were software updates. So when is the AppleTV going to be able to play games like Gears of War, or Trusty Bell, or Katamari Damacy? Or when is the AppleTV going to let you upgrade the hard drive from one size to another? Shoot even the PS3's hard drive is upgradable.

Most everything it (PS3) does is software driven as well. Can you fold protiens on your AppleTV (without hacking it)? Can you run Linux? When is the AppleTV going to be able to play BluRay movies? Or how about DVD's?


For what the ATV does, it does pretty well, but lets not act like it is the only piece of consumer electronics that can have it's software updated to do new things.

Cave Man
Jan 18, 2008, 10:28 AM
This is not the issue. AppleTV isn't "rejecting" anything. It doesn't have the software present in the current iteration to enable Dolby Digital pass through.

I am pretty sure the ATV checks movies for certain containers from iTunes, then reports back to iTunes if the file is incompatible. (Of course, this could also be a function of iTunes only, if it has such algorithms to do so.) You can add some movies to iTunes that will play just fine in iTunes, but they will not sync with the ATV nor with they show up on the ATV menu if you stream. For example, I have many .mov movies with AC3 DD on my home theater Mac Mini that are in iTunes and play in iTunes (as well as Front Row and QuickTime stand-alone) with 5.1 DD, but they do not show up on my ATV because the ATV cannot play .mov files with AC3.

I should clarify my earlier statements about Dolby Digital by pointing out that AppleTV will most likely NOT actually have a Dolby Digital decoder to the best of my knowledge. It doesn't need to. ...Your Dolby Digital RECEIVER (or standalone surround processor, e.g. Dolby DP-564) does the actual decoding. That's what pass-through is.

Yes, I know this. I've been doing it with my Mini and Onkyo receiver for about 2 years now.

Avatar74
Jan 18, 2008, 10:58 AM
So let me get this straight. You talk about features of the AppleTV that are software driven, I say that the 360 can be updated to do the same thing. You then turn around and bring up hardware changes. Please stop moving the goal post.

I didn't move the goal post. You did, when you wrote this (emphasis mine):

The 360 could be updated to do everything the Apple TV can do.

My reply was in response to that statement... to which the answer is simply, "No."

Avatar74
Jan 18, 2008, 11:13 AM
I am pretty sure the ATV checks movies for certain containers from iTunes, then reports back to iTunes if the file is incompatible. (Of course, this could also be a function of iTunes only, if it has such algorithms to do so.) You can add some movies to iTunes that will play just fine in iTunes, but they will not sync with the ATV nor with they show up on the ATV menu if you stream. For example, I have many .mov movies with AC3 DD on my home theater Mac Mini that are in iTunes and play in iTunes (as well as Front Row and QuickTime stand-alone) with 5.1 DD, but they do not show up on my ATV because the ATV cannot play .mov files with AC3.

I'm curious as to why it is, but based on what you're saying here it's not a conscious "restriction"... it simply appears that one piece of hardware is lacking software that other has for decoupling AC-3 from the H.264 stream. Or it could be a different issue... for example, there are some .mov files that, with AAC audio alone, will not play on AppleTV because the video stream's bitstream is too high for AppleTV to handle. It appears the limitation is H.264 Main Profile 3, with a max bitrate of 5Mbps.

That being said, it doesn't appear that AppleTV is deliberately rejecting the file just to be bastards about Dolby Digital... which was my original point in my reply to you.

diamond.g
Jan 18, 2008, 11:16 AM
I didn't move the goal post. You did, when you wrote this (emphasis mine):



My reply was in response to that statement... to which the answer is simply, "No."

I see. My reply was in response to your statement about software functionality. I even gave the video marketplace as an example. I didn't think anyone would think hardware was being talked about. That is why I claimed you moved the goal post. In retort I asked the same thing of the AppleTV. Until it can play the same games the PS3 and 360 can play, or (BD, HD DVD, DVD) disc, then it too can't be updated to do everything the 360/PS3 can do.

Just curious, if the 360 elite can do more than the ATV why wouldn't it be more expensive? (same question for the PS3)

Avatar74
Jan 18, 2008, 11:33 AM
I see. My reply was in response to your statement about software functionality. I even gave the video marketplace as an example. I didn't think anyone would think hardware was being talked about. That is why I claimed you moved the goal post. In retort I asked the same thing of the AppleTV. Until it can play the same games the PS3 and 360 can play, or (BD, HD DVD, DVD) disc, then it too can't be updated to do everything the 360/PS3 can do.

Just curious, if the 360 elite can do more than the ATV why wouldn't it be more expensive? (same question for the PS3)

Suffice it to say they are different devices with pros and cons each...

But just for argument's sake... How does a software update get distributed and installed to the XBOX 360? Is it automatic? Or do you have to go through some gyrations to do it, and if so, what are they?

diamond.g
Jan 18, 2008, 11:52 AM
Suffice it to say they are different devices with pros and cons each...

But just for argument's sake... How does a software update get distributed and installed to the XBOX 360? Is it automatic? Or do you have to go through some gyrations to do it, and if so, what are they?

Software updates are done in one of 3 ways. This is the case for both the PS3 and the 360.


Sign into Xbox Live (or PSN), the system see's you aren't running the latest firmware and forces you to upgrade. In the 360's case if you refuse it logs you out of live.
Put a newer game disc that has the new firmware in the system.
Download the update from MS or Sony and burn it to a disc. This method is the most involving one, dunno how many people actually do this.

Avatar74
Jan 18, 2008, 01:22 PM
Software updates are done in one of 3 ways. This is the case for both the PS3 and the 360.


Sign into Xbox Live (or PSN), the system see's you aren't running the latest firmware and forces you to upgrade. In the 360's case if you refuse it logs you out of live.
Put a newer game disc that has the new firmware in the system.
Download the update from MS or Sony and burn it to a disc. This method is the most involving one, dunno how many people actually do this.


All feature-matrixes aside...

The above description makes it appear as if IP were an afterthought to product development for the 360. Yes, I know it has IP, uses IP and a lot of gameplay/movies revolve around internet access on it... but let me explain...

In the late 1990's, several organizations including Mitsubishi, Thomson (RCA) and Hitachi got together and formed HAVi, a forum standard that was to be built around IEEE-1394 Firewire (which Apple introduced) and allow networking of audio/video components in an integrated system. That project seems to have completely died.

Then HDMI came about, but HDMI is not an Internet Protocol capable transport. The majority of the industry backed this instead of HAVi.

I've been scratching my head on this one, except to say that anything "IP" scares the crap out of RIAA and MPAA. They recoil in horror at the thought of it being hacked. So they went with HDMI that incorporated HDCP which originated with the advent of DAT.

The problem with this approach is that it's not really a great solution for the consumer in the 21st century who wants easy interoperability between not only home theater components, but integration of all aspects of their digital lifestyle... The most logical solution being to employ the LAN as the backbone to connect it all. That's the holy grail, and AppleTV is the only device that really truly takes IP seriously.

The reason I say XBOX treats IP as an after thought is this... IP is there simply to enable multiplayer games and XBOX Live access... but then you've got goony ergonomics like this update process. Unless you have an XBOX Live subscription, the process to update would be to buy a game and update. This is fine but it certainly indicates that IP was an afterthought rather than the central guiding scope and purpose of the device.

That really means that XBOX is a gaming and movie machine that happens to also have an ethernet port. It is not a convergence device in the true sense of the word. Nothing wrong with that. But that's not the most competitive space to be in... It was, but it will not remain that way for long.

True convergence devices have IP at their heart. They are communications devices first and foremost... conduits for access to content. What content? Well, frankly any content that software can be devised for. So that got me thinking...

Why HDMI? Why don't AV components ALL speak IP? Tech convergence will not happen, truly, until AV components speak the same language as the rest of your digital devices... and the most common language is IP. Hundreds of millions of devices worldwide speak it. There's no reason I shouldn't be able to use iPhone's interface as a "remote control" to tell my DVD player what to do, or to browse a graphical coverflow list of albums on my NAS and dictate which system in the house I want them streamed to at that given moment.

The only reason this doesn't happen sooner (as a standard feature, not an aftermarket geek hackjob) is obstinacy in the industry and fear of decentralization of information control. Information is a commodity with a value that gets artificially inflated by arbitrary barriers just the same way DeBeers controls the price of diamonds by hoarding 99% of the world's supply and keeping it locked up. That can change with broader implementation of IP.

The reason I'm intrigued by the possibilities of AppleTV is not simply that I'm an Apple fanboy... and I'm not a fanboy because of any of the latest mania. I've been a fan of Apple design since the 1970's. What intrigues me is that an AppleTV type of device is a very subversive weapon against traditional media control. Who needs to subscribe to 900 channels of crap when you can access any one of thousands of professional-grade podcasts on any subject you can possibly imagine? Who needs record companies when artists can compose, record, produce, market, distribute directly from their studio to your living room? The idea AppleTV seems to be aiming for is one of lethal force against TV networks, against motion picture studios, record companies, news outlets, media conglomerates. And the funny thing is, the motion picture studios probably don't even realize they're helping Apple help us (viewers) nail their own coffin shut.

I see it growing into a convergence hub that allows two-way communication between multiple platforms and AV appliances and gadgets to bring it all together under a dynamic UI that adapts to suit the job at present... I see devices like these sprouting up everywhere in the near future as others enter into the game... rather than a bunch of devices that cannot talk to one another and have to be junked every time someone invents a new grooved frisbee.

Mac In School
Jan 18, 2008, 09:58 PM
Wow @ this thread. Way too technical for me.

Will I be able to rip my DVD's 5.1 tracks to the :apple:TV, or what?

Cave Man
Jan 18, 2008, 11:06 PM
Wow @ this thread. Way too technical for me.

Will I be able to rip my DVD's 5.1 tracks to the :apple:TV, or what?

We don't know yet. Several things will need to occur. If Apple provides the ATV's Quicktime with the ability to send AC3 DD info out the optical port or over the DVI connector AND your receiver or TV can decode DD, then it is possible. But Apple may keep us from sync'ing or streaming from iTunes, thus restricting playback to HD movies downloaded directly to the ATV from the iTMS.

If Apple doesn't do anything tricky to prevent sync'ing or streaming, then it is likely Handbrake can be updated to include AC3 passthrough to compatible files (as you can already do with Quicktime or Front Row with a Mac and Perian). Alternatively, they could provide ATV Quicktime with the ability to play mkv or avi movies, which can already be encoded with AC3 passthrough. Keep your fingers crossed.

Mac In School
Jan 19, 2008, 01:33 AM
Cool. Thanks. I'll hurry up and wait.

mtbdudex
Jan 19, 2008, 02:44 AM
That's great that you take an interest in home theater. Paradigm's a good set of speakers for the price, btw.

I'm curious... what are you planning to use for the screen? It appears from your notes on the image you are doing front projection because you're cutting a screen to 2.35:1.*

It doesn't appear you have enough room for 100" HD projection (my uncle had 9 feet, but needed 18, for a Barco cinema HD projector... so his carpenters built a reflector frame in the rear projection room!)... Are you planning to go LCD or plasma? My suggestion would have been a recessed wall for an LCOS display... nothing beats LCOS for the 3 C's except a Trinitron XBR cathode ray tube.

* Cut that screen wider. The actual aspect ratio of Panavision (http://www.panavision.com/aspect_ratio.php) (mistakenly called "scope" as a reference to now defunct CinemaScope) is 2.40:1, not 2.35:1.... Yes, I know the DVD's all say the latter but they're referring to the cropped image with safe lines. You can have black curtains to matte accordingly, but in order to actually project the entire image, TV-safe areas and all, the screen itself has to be 2.40:1. Of course if you're watching HDTV programming it doesn't matter because most of it, much to my chagrin, is still blocked for 4:3 anyway. I had a big discussion with the exec producer of Comanche Moon (CBS) over this just yesterday.

Avatar74;
Sorta off topic of the OP, but also related to my basement Home Cinema, since I might use AppleTV in the future and I'd really like full lossless surround sound and 1080p.

My equipment:
Frt Proj: Sony VPL-VW60 (I just picked that up tonight, still in the box!)
Screen: I am going CinemaWide, was in Nashville all week and had a chance to experience that at HiFiBuys, http://www.avsforum.com/avs-vb/showthread.php?t=977638
A/V: Denon 4308CI
Speakers: Paradigm Monitor 9's, CC390 center, 4 ADP390
Check out my IB subwoofer I'm gonna build:http://ibsubwoofers.proboards51.com/index.cgi?board=projects&action=display&thread=1198261510&page=1

For Home Theatre/Audio, I've surfed a few of the boards, such as; S&V, Home Theatre Shack, etc, seems the one I like most is AVS Fourm.
(I'm "mtbdudex" at all of them)
They have a specific section on 2.35:1 screens, I'm going with the Constant Height set-up, my Sony VW60 is capable with an external Anamorphic lens.

My room is 14.5 feet wide , 18.5 feet long, 8.75 feet tall, if you look at the IB post you can see I tried to minimize sound intrusion into my home via some soundproofing measures. Of course once my room is all finished/etc I'll work on some acoustic treatments to handle some of the basic issues, 1st order harmonics, etc. The Audessy in the Denon should help, I'm a newbie in acoustic treatments and am willing to learn/apply some stuff, but I'm not gonna go totally wild and have these tilted panels everywhere either.
I'm mounting the frt proj with 16 foot throw distance (lens to screen), proj of course is "upside down", mounted from ceiling.

diamond.g
Jan 19, 2008, 07:03 AM
All feature-matrixes aside...

The above description makes it appear as if IP were an afterthought to product development for the 360. Yes, I know it has IP, uses IP and a lot of gameplay/movies revolve around internet access on it... but let me explain...
<snip>
I see it growing into a convergence hub that allows two-way communication between multiple platforms and AV appliances and gadgets to bring it all together under a dynamic UI that adapts to suit the job at present... I see devices like these sprouting up everywhere in the near future as others enter into the game... rather than a bunch of devices that cannot talk to one another and have to be junked every time someone invents a new grooved frisbee.
Actually, IP is very important to the 360. Xbox Live is free (Silver). When you first boot the console it has you create a profile. If the console has net access it autocreates a XBL account.

If AppleTV was intergrated with iChat where you can see when friends come on. You can see what movies friends are watching. You can chat (text, audio, or video). That would be a pretty close to the experience of XBL outside of playing games together. The 360 is very friend centric which requires net access.

Actually I think iChat interface for AppleTV would be the coolest thing they could do. Add the ability to see what others are watching (meaning you can't watch what they are watching but can see the title). Or just updates on what activities they are up to. Right now the AppleTV is a one way experience. You only download to the box. Data doesn't leave the box. Make it two way. That would open up tons of possibilities.


Topic: DD+ is more likely as a passthrough means. It wouldn't add too much in the way of download size or even bit-rate (IMHO). THD or DTSMA start out too big to make it worthwhile. Can DPLII output sound only from the rear speakers? Some folks here make it sound like there is no difference in having matrix sound versus having discreet sound. You know the scene in the Matrix where Neo dodged bullets like he was an agent, can DPLII have the bullet fire sound just like it does when using DD?

Avatar74
Jan 19, 2008, 11:20 AM
mtbdudex and diamond.g, and others, something I'd overlooked which should have been rather obvious to me as to why AppleTV cannot support "HD" Surround sound at this point...

The simple explanation is this: Neither Dolby TrueHD nor full-bandwidth Dolby Digital Plus would be feasible because the bitstream requirements are astronomical relative to Dolby Digital AC-3.

Let me illustrate...

H.264 Main Profile 3.0 has a cap of 10Mbps. Currently the AppleTV operates at a maximum around 5Mbps for the total bitstream, audio and video.

Now, this is not a problem with AC-3 pass through because the standard AC-3 5.1-channel bitstream is 448 Kbps. Dolby Laboratories states that at 448 Kbps their format is acoustically transparent... that is, it's indiscernible from an uncompressed source. I'm not going to get in an argument here... I've done professional mastering, and I agree with Dolby Labs engineers. I've heard it all and no anecdotal argument from an audiophile (especially those who have never read Ken Pohlmann's Principles of Digital Audio) is going to change that.

The fact is, if uncompressed 24-bit uncompressed (Linear PCM) multichannel audio is what you want, then there's no mathematical way around this:

24-bit amplitude resolution X 48 kHz sampling frequency X 8 channels=

9.216 Mbps bitstream (audio only)

Clearly, you should see several problems, including the tremendous file size, the ridiculous amount of time it would take to download, the hardware and software limitations, and so on.

At some point in the future this might not be a problem, but currently it's just not feasible.

But, I wouldn't worry about it for a while... Most film soundtrack masters have been mastered to 16-bit, 48KHz, resolution. This means that there's a significant gap between the amplitude resolution of the source, and the amplitude resolution possible with HD audio. You will gain no added benefit from the tremendous number of soundtracks that are not going to be remastered entirely from the 24-bit multitrack master.

But I would like to see such a system in the future. 24-bit amplitude resolution is noticeably more dynamic than 16-bit. For now, we'll have to live with AC-3. I've done professional soundtrack mastering and I can live with that just fine and frankly, so can you.

Cave Man
Jan 20, 2008, 05:10 PM
I have a few seconds of a movie that can stream to the ATV and it has the chatter that you hear from an AC3 soundtrack that's going through a non-DD receiver. Here's what I did:

1. Transcoded the movie from a VIDEO_TS folder of a ripped DVD to and AVI with AC3 passthrough using Handbrake.
2. Opened the AVI file and did a "Save As" to convert it to a MOV container. (This file plays on my Mac Mini with Perian to produce 5.1 surround with Quicktime, Front Row or iTunes.)
3. Dropped this MOV file onto VisualHub and started the conversion to MP4.
4. Aborted the conversion after a few minutes just to see if it would work.
5. Dropped it into iTunes and it was accepted.
6. Looked for it from the ATV and it was there!!
7. Played it from the ATV and my non-DD Sony receiver (Dolby Pro Logic) played the chatter from the movie.

So, is it possible that this file could provide DD 5.1 on an ATV? Would the ATV need the Perian codec installed for the passthrough? Ideas? Suggestions? I'm sure there's something that would preclude this, but my excitement is because it's the first time I've been able to get a movie file with AC3 5.1 surround to show up on the ATV. If anyone has an ATV connected to a DD receiver, I'd be happy to share this snipped of movie if they want to test it out.

Avatar74
Jan 20, 2008, 06:08 PM
So, is it possible that this file could provide DD 5.1 on an ATV? Would the ATV need the Perian codec installed for the passthrough? Ideas? Suggestions? I'm sure there's something that would preclude this, but my excitement is because it's the first time I've been able to get a movie file with AC3 5.1 surround to show up on the ATV. If anyone has an ATV connected to a DD receiver, I'd be happy to share this snipped of movie if they want to test it out.

I can't answer whether or not it will for sure work because the update is not out yet... anyone would be speculating as to the method used by Apple for packing and unpacking the AC-3 bistream.

What do you mean by "chatter"? I don't want a copy of the file as that would constitute piracy. I have Dolby Digital encoding tools myself... I'll take one of the Dolby Digital trailers and encode it as H.264 with AC-3 pass through to assess the results when the AppleTV update is out. I use those for system calibration on my home theater since they're designed more dynamically than the average soundtrack mix so one can quickly assess operation of all six channels and adjust accordingly where there are dropouts/level mismatches, etc.

monotone1972
Jan 22, 2008, 04:09 AM
hey ... completely new ... but want to track this thread, how do i subscribe to it?

sorry, i know i shouldn't post here ... but don't know how to subscribe?

Diatribe
Jan 22, 2008, 06:29 AM
hey ... completely new ... but want to track this thread, how do i subscribe to it?

sorry, i know i shouldn't post here ... but don't know how to subscribe?

On the top of the thread you have an icon called "thread tools". In the drop-down menu is the subscribe function.

proagg
Jan 26, 2008, 10:23 AM
I have a few seconds of a movie that can stream to the ATV and it has the chatter that you hear from an AC3 soundtrack that's going through a non-DD receiver. Here's what I did:

1. Transcoded the movie from a VIDEO_TS folder of a ripped DVD to and AVI with AC3 passthrough using Handbrake.
2. Opened the AVI file and did a "Save As" to convert it to a MOV container. (This file plays on my Mac Mini with Perian to produce 5.1 surround with Quicktime, Front Row or iTunes.)
3. Dropped this MOV file onto VisualHub and started the conversion to MP4.
4. Aborted the conversion after a few minutes just to see if it would work.
5. Dropped it into iTunes and it was accepted.
6. Looked for it from the ATV and it was there!!
7. Played it from the ATV and my non-DD Sony receiver (Dolby Pro Logic) played the chatter from the movie.

So, is it possible that this file could provide DD 5.1 on an ATV? Would the ATV need the Perian codec installed for the passthrough? Ideas? Suggestions? I'm sure there's something that would preclude this, but my excitement is because it's the first time I've been able to get a movie file with AC3 5.1 surround to show up on the ATV. If anyone has an ATV connected to a DD receiver, I'd be happy to share this snipped of movie if they want to test it out.

Caveman, I could not replicate the same results no matter how I tried. Here's what I did.

1. I ripped a short section of Star Wars Ep 1 as AVI using AC-3 passthru in Handbrake. I tested this on my Windows box with processes my surround. It worked perfectly.
2. I saved as a MOV using Quicktime Pro.
3. I converted 1st in VisualHub using "for AppleTV settings" in the iTunes tab with the h.264 codec, and then using the "mp4" tab with h.264 checked. Neither worked. I got stereo out of both. This could possibly be because of my setup, but I used VLC to playback every video and when the surround worked, I knew it and I had the option for 5.1 in the right-click menu.
*4. I tried converting straight from avi to mp4 using ffmpegx with passthru audio, but got no sound at all.
**Other things I tried - converting to mp4 with DPLII, Dolby Surround, and 6-channel discrete in handbrake and none of them gave me proper sound in quicktime or VLC. The best option I got was "2 front 2 rear" which left my center channel high and dry. Using DPLII and Dolby Surround the only options I had were "stereo, reverse stereo, left, and right." These were also the only options I had available for the DPLII.mp4 file you provided.

I want to get an appleTV soon, but I need to convert my library 1st, so here are my questions. you said 6. Looked for it from the ATV and it was there!! but then you said ...it's the first time I've been able to get a movie file with AC3 5.1 surround to show up on the ATV. So did it show up or not? Secondly, since I will continue (for now) to have the windows box process my audio which can handle optical input from the apple tv, I would assume that processing surround aac is possible or am I confusing some terms? Can anyone confirm this? And finally, can anyone with a hacked apple tv give me some input on their surround sound experience? Thoroughly confused,
proagg

Cave Man
Feb 12, 2008, 03:11 PM
I just noticed this on the ATV web page:

MPEG-4: Up to 3 Mbps, Simple Profile with AAC-LC audio up to 160 Kbps (maximum resolution: 720 by 432 pixels at 30 fps) in .m4v, .mp4, and .mov file formats

I don't think .mov was listed before - can someone else recall? If not, then that suggests the way I encode for my Mac Mini HTPC may work with the ATV2 as described here:

1. Transcode the movie from a VIDEO_TS folder of a ripped DVD to an AVI with AC3 passthrough using Handbrake.
2. Open the AVI file in QuickTime Pro and do a "Save As" to convert it to a MOV container.
3. Drop it into iTunes. (should show up as a movie)
4. Looked for it from the ATV.
5. Does it illuminate your Dolby Digital indicator on your receiver (via optical connection)???

Does anyone have 30 minutes to give it a try? Please report back here if you do.

TIA.

proagg
Feb 12, 2008, 03:27 PM
TAKE 2 IS HERE PEOPLE!!!! Woot! I will update as soon as I get home, and then I will try your idea Cave Man. I hope this makes Surround Sound easy.

Cave Man
Feb 12, 2008, 04:29 PM
Here's the intro. Notice it has AC3.

musicpenguy
Feb 12, 2008, 05:19 PM
Is that an HD download from the Apple TV that you hacked into to get out or - how was that one encoded Handbrake ? - Please share ! :)

Cave Man
Feb 12, 2008, 05:21 PM
That's straight from the ATV Take 2 upgrade disk image. I dl'd it from Apple and pulled it out of the finder. What's important, I think, is that it appears to be just a plain ol' AC3 file. That's very encouraging.

jaw04005
Feb 12, 2008, 05:50 PM
That's straight from the ATV Take 2 upgrade disk image. I dl'd it from Apple and pulled it out of the finder. What's important, I think, is that it appears to be just a plain ol' AC3 file. That's very encouraging.

What folder is the new Apple TV intro movie in?

proagg
Feb 12, 2008, 06:02 PM
I just tried to 'see' an MOV from the appleTV, and it wouldnt pick it up. I will keep trying though.

proagg
Feb 12, 2008, 07:59 PM
OK, I followed the following steps I found on apple's forums and I got 5.1 working, but the video was (using Xvid) unbearable. After switching to the FFMPEG encoder, the video looks great and surround sound works great. The only thing is, the sound wasn't synced up. Hopefully with a full Movie it will match properly. I also don't know how this will work with all my AVI's, but I'm pretty excited to get this far.

"Ok, I managed to get Dolby Digital from a Video file. The steps are very easy:

Create an mp4 from your DVD or other source with Handbrake or Visual Hub - Audio Settings are not important

If you are ripping a DVD then open Mac the Ripper, choose Chapter extraction, open streams and select the Audio File you want to be extracted

You will now need Quicktime Pro

Open both files (the mp4 and the ac3) in Quicktime. Copy the ac3 stream and paste it to the mp4 file

Save the file as a MOV movie

Import it in iTunes

That was it!!!"

proagg
Feb 12, 2008, 10:25 PM
I feel like I'm talking to myself here, but maybe my findings will save someone else the trouble...anyways here's what I've learned so far (in no special order):

Although not all MOVs will go straight to the AppleTV, using the above method gets the MOV into iTunes and AppleTV every time.

IMHO...The Xvid and FFMPEG encoders suck! Go with x264 and the h.264 codec, it produces excellent video in comparison.

Although the author of the above directions did not explain this, I find it necessary to choose "no audio" in handbrake or else Quicktime slaps the two audio tracks together, creating a crappy echo sound.

When I did a full movie encode, Mac The Ripper added a few seconds of silence at the end of the audio, so check your lengths when adding the video and audio.

The author doesn't explain the quicktime process in detail, so there's a couple things I figured out: 1. Select the whole clip of audio via "select all", and then copy. 2. If you try and paste it with the video, quicktime puts them side-by-side, so instead select the whole clip of video and then choose "Add to selection and scale" (you might be able to choose "add to movie", but I haven't tried).

Kinetic
Feb 12, 2008, 10:32 PM
I feel like I'm talking to myself here, but maybe my findings will save someone else the trouble...anyways here's what I've learned so far (in no special order):


No, please keep up the posting. It does help folks (like me) who are curious to see how this works. I've held off buying AppleTV until this update mainly for the 5.1 audio. Any information found is appreciated

TuckBodi
Feb 12, 2008, 11:14 PM
When I did a full movie encode, Mac The Ripper added a few seconds of silence at the end of the audio, so check your lengths when adding the video and audio.


So what did you do to get rid of the extra seconds and/or align with the video?

proagg
Feb 13, 2008, 08:35 AM
So what did you do to get rid of the extra seconds and/or align with the video?

Haha, I'm still trying to figure that part out. I have tried cutting off the end in QT, because it seems to stay synced from the beginning, but I cant get it exact, so it doesn't sync properly. I thought I had gotten the audio out incorrectly in MTR, because I chose specific chapters, but when I switched to "title only," MTR claimed that the output would be exactly 2:16:05, but it actually added even more time than thru chapter selection (it came out 2:18:00). So this is frustrating.

On the AVI side FFMPEGX, a shareware app, seems like it will work for the AVIs I own. I successfully stripped out the AC3, and the MP4 is on its way. If it works I might post instructions.
Edit: I don't know why, but FFMPEGX added over an hour worth of empty space to both the audio and video...searching for a better solution.

Update: VisualHub has been updated today to support AppleTV in 5.1! I don't own this software yet, but I am definitely going to purchase it next paycheck. User reports seem good so far, and my thinking is that the easiest way to get content from DVD to AppleTV will be thru Handbrake as an AVI, and then thru VisualHub. But I can't confirm anything yet. You can check out the thread on the VisualHub forums here. (http://www.isquint.org/cgi-bin/ikonboard.cgi?act=ST;f=8;t=4990;st=30) Also, you can see the changelog here. (http://www.techspansion.com/visualhub/ChangeLog.rtf)

Superman07
Feb 13, 2008, 01:44 PM
I didn't want to hijack the VisualHub thread...

I think this will mean more to many of you than me since you're more familiar with a lot of the terms and what means what on a technical level.

Anyway, it seems like the Handbreak crowd is going a different route (at least for the time being) than VH and making some progress.

http://forum.handbrake.fr/viewtopic.php?f=4&t=195

dynaflash
Feb 13, 2008, 02:10 PM
er thats an old thread from back when we originally put dpl, dpl2 and 6 channel discrete aac into HB.

That does not provide 5.1 dd for the atv2 unfortunately.

Our solution would involve .mp4 and not .mov for the record. :)

Superman07
Feb 13, 2008, 02:24 PM
er thats an old thread from back when we originally put dpl, dpl2 and 6 channel discrete aac into HB.

That does not provide 5.1 dd for the atv2 unfortunately.

Our solution would involve .mp4 and not .mov for the record. :)

Sorry for the mistake. I think I even looked at the 2007 date, but it didn't register vice 2008. :( Very tired today.

Cave Man
Feb 13, 2008, 08:53 PM
I just tried to 'see' an MOV from the appleTV, and it wouldnt pick it up. I will keep trying though.

Same problem here. I could not get it to see my 5.1 DD MOV files that work just fine on my Mini home theater system. I've updated Visual Hub and am currently encoding Revenge of the Sith. I'll give it a look-over, but others are reporting VH only puts in one audio track - either AC3 or 2-channel. The intro movie of Take 2 has two audio tracks; AC3 and 2-channel. But on inspection, the AC3 was deslected. There must be a way to encode 2-channel and AC3 in the same file. I suspect it's only a matter of time until this is resolved; perhaps days or weeks (fingers crossed).

JasonKerner
Feb 14, 2008, 01:43 AM
Last night, I encoded an episode of Sarah Connor Chronicles, using the new Apple TV 5.1 preset in VisualHub. Worked perfectly, got a .Mov, tagged it in iTunes, and my Denon AV amp showed Dolby Digital and it worked great. The source file was a 720p MKV with an AC3 original soundtrack.

Jason

TransientWolf
Feb 14, 2008, 08:17 AM
..............tagged it in iTunes.........

Am I right in understanding that you can tag the basics but extended tagging won't work, not indeed will cover art (which is a bit of a dealbreaker for me)

fivepoint
Feb 14, 2008, 08:31 AM
Last night, I encoded an episode of Sarah Connor Chronicles, using the new Apple TV 5.1 preset in VisualHub. Worked perfectly, got a .Mov, tagged it in iTunes, and my Denon AV amp showed Dolby Digital and it worked great. The source file was a 720p MKV with an AC3 original soundtrack.

Jason

I would like to know the answer to the post above mine... and also whether or not the audio will still work on 'regular' stereo speakers. It isn't JUST 5.1 surround is it? It will still work fine without a surround system?

Also, how much more size are the files taking up with the enhanced surround sound?

NightStorm
Feb 14, 2008, 09:05 AM
I would like to know the answer to the post above mine... and also whether or not the audio will still work on 'regular' stereo speakers. It isn't JUST 5.1 surround is it? It will still work fine without a surround system?

Also, how much more size are the files taking up with the enhanced surround sound?

No, the files encoded with the latest VH require a DD decoder in order to hear anything. Unless you are running through a receiver, you will not have sound. The HB team are working to have both AAC and AC3, like Apple has done with the new intro video.

Superman07
Feb 14, 2008, 09:06 AM
I would like to know the answer to the post above mine... and also whether or not the audio will still work on 'regular' stereo speakers. It isn't JUST 5.1 surround is it? It will still work fine without a surround system?

Also, how much more size are the files taking up with the enhanced surround sound?

My understanding right now, that the answer to your question is "No".

It's ONLY a 5.1 solution. They are working on a solution that would allow a 2.0 and 5.1 setup to work of the same file.

However, I didn't know an updated version of HB was out that would do the 5.1. I thought they were still working it out over in their community.

Lastly, what would happen if you used a 5.1 that works but unplugged 3 speakers? Wouldn't you just get 2.1, or would they receiver go all nuts? Edit: This still wouldn't solve the problem relative to iPods and iPhones.

Cave Man
Feb 14, 2008, 09:11 AM
It is conceivable that you could encode the show twice; one with AC3 and the other with stereo (Dolby Pro Logic II or Surround). You could then add one of the audio tracks to one of the files, providing both AC3 and 2-channel for the same video. Since Apple is apparently doing this, there must be some software decision made by the ATV to decide whether to play back AC3 or 2-channel.

NightStorm
Feb 14, 2008, 09:41 AM
However, I didn't know an updated version of HB was out that would do the 5.1. I thought they were still working it out over in their community.
There isn't. It is their development code, and it is not a complete solution at all. They are working on it, and it'll be ready as soon as they figure everything out.

Cave Man
Mar 15, 2008, 11:24 AM
I have updated the first post of this thread to reflect changes to the ATV2. I welcome suggestions and corrections for improving this post.

b4ckd00r5p1d3r
Sep 24, 2011, 11:37 AM
Hi I have questions is there a way to pm you or email you?

(Updated 15 March, 2008)

With the Apple TV 2 update, Dolby Digital 5.1 surround sound in now possible. This post provides information about how to get your system set up for 5.1 surround sound. If any of this is incorrect, I welcome and appreciate corrections by other forum members. As new information becomes available, I will revise this post.

1. Definitions

A. Dolby Digital AC-3 (DD). This is usually 6 channels (termed '5.1') that is sent over a digital connection, either by HDMI or optical cables from the Apple TV to a receiver with the respective inputs. The channels for DD are L, R, C, Rr, Lr and the low frequency LFE channel. The LFE is the '.1' channel.

B. Dolby Pro Logic II (DPLII). This is a 5-channel surround signal that can be sent over analog or digital connections. The 5 channels are R, L, C, Rr and Lr. DPLII also can be encoded and transmitted over stereo (i.e., 2 lines, right and left) cables to a receiver that is capable of decoding the signal and outputting to all 5 channels.

C. Dolby Pro Logic (DPL) (and Dolby Surround, DS). This is a 4-channel surround signal that can be sent over analog or digital connections. The 4 channels are right (R), left (L), center (C) and rear (r - two signals Rr and Lr, but it is mono so only counts as one channel). DPL can be encoded and transmitted over stereo cables to a receiver that is capable of decoding the signal and outputting to all 4 channels.

In Apple TV files DPLII, DPL, DS and stereo are encoded in AAC tracks.

You can read more about these from the pulldown at Dolby's surround sound web page.

http://www.dolby.com/resources/tech_library/index.cfm

2. Hardware

A. Apple TV. The Apple TV has three means of delivering audio: over the HDMI cable, through its optical port, and through its two channel RCA jacks. While the HDMI and optical port can deliver both digital (DD) and analog (DPL, DPLII, DS, stereo), the RCA jacks can only deliver analog audio.

B. TVs. Many new TVs have inputs for HDMI and optical cables, as well as analog RCA jacks. However, most only decode Dolby Digital delivered through their ATSC tuners (e.g., over-the-air antenna, satellite or cable connections). They generally are unable to decode DD from other hardware sources, such as an Apple TV or DVD player. In addition, they cannot passthrough DD from a device to a receiver; the TVs can only pass analog audio to the receiver. The exception to this rule is the built-in ATSC tuners that all new TVs have. These connections from a TV to a receiver are HDMI, optical cable or coaxial cable, each of which is capable of delivering digital audio information to the receiver.

C. Receivers/Amps. Most receivers today have the ability to receive and decode Dolby Digital audio (and DTS digital audio, but which will not be discussed since the ATV2 does not do DTS). The least expensive units have optical and/or coaxial digital audio inputs, often more than one, while the more expensive units have these inputs as well as HDMI inputs. In addition, some of the receivers with HDMI inputs also have HDMI outputs and can be used to control your video as well. These HDMI receivers are able to provide DD 5.1 surround while also passing along video to your TV.

3. Software

A. Quicktime Player. With the release of the Apple TV 2 update, Quicktime for the ATV2 saw an update with the ability to passthrough AC-3 Dolby Digital (e.g., 5.1) surround sound, provided the movie file has such a track and that a receiver capable of decoding DD is connected directly to the ATV. This feature of autoselecting audio tracks in ATV's Quicktime apparently is not available for Macs, although Quicktime on Macs can passthrough AC-3 DD if the track is enabled (and with DVDs and DVD Player app).

B. Handbrake. With the release of version 0.9.2, Handbrake (http://handbrake.fr/) included the ability to encode videos with both AAC (analog) and AC-3 5.1 (digital) surround sound, provided your source DVD has 5.1 surround sound tracks. By choosing the "Apple TV" preset in Handbrake, you get both audio tracks, with the AAC turned "on" and the AC-3 turned "off" by default. (This is also how the high-def with DD movie rentals from Apple are arranged, too.) The new Quicktime that ships with the ATV2 update automatically determines if (1) the movie file has an AC-3 track and (2) if your receiver is capable of decoding AC-3 audio. If both conditions are true, then the ATV will enable the AC-3 track. Otherwise, the ATV will only use the AAC track as the audio source.

4. Connections

A. Non-HDMI Receiver. If your receiver does not have HDMI inputs, then your best solution is to connect your Apple TV to your TV by its HDMI cable or component cables, then use a Toslink cable to connect your ATV to your receiver. You cannot connect your Apple TV to your TV with HDMI or optical cable and expect your TV to passthrough DD 5.1 to your receiver. The receiver must be connected directly to the ATV by optical cable. The audio can only be passthroughed once (but video can be passed at least twice). This is because of Digital Rights Management issues. If your TV does not have HDMI and you are using the component video connections from your ATV, then you should also connect your ATV audio to your TV using the RCA audio jacks.

B. HDMI Receiver. If your receiver has HDMI inputs, connect your ATV to it using an HDMI cable. You then need to connect your receiver's video-out to your TV, either by HDMI, component or composite cables. In this way, you will get DD 5.1 surround sound.

C. Listening to audio without having your TV on. If you listen to music, audio books or audio podcasts with the ATV, you may not want your TV on while using these media. If your RCA jacks on your ATV are unused, you can connect them to your receiver in such a way that it is unnecessary to leave your TV on while listening to audio media. For my setup, I have our ATV connected to our TV by HDMI, and to our Onkyo receiver by its optical cable. Because the RCA jacks on our ATV were unused, I connected them to the "CD" input on the receiver. With this setup, I set the receiver to CD mode, then start a music playlist from the ATV, then turn off the TV. The music continues to play until the last song.

See this post (http://forums.macrumors.com/showthread.php?p=5162084#post5162084) for the break in this thread between ATV2 and ATV1.


*******************************************************
* The information below is the original post and applies to
* pre-ATV2 only. If you still use versions 1.0 or 1.1, you should
* use this information.
*******************************************************

OK, I'm going to try to clarify audio on an Apple TV versus a Mac Mini. I hope to be clear and accurate, but your mileage may vary. I'm only going to discuss Dolby Labs' technology, and not DTS. I am no expert, but this is the information I've manage to pull together. If any of this is incorrect, I welcome and appreciate corrections by other forum members. As new information becomes available, I will revise this post.

1. Definitions

Dolby Pro Logic (DPL) (and Dolby Surround, DS). This is a 4-channel surround signal that can be sent over analog or digital devices. The 4 channels are right (R), left (L), center (C) and rear (r - two signals Rr and Lr, but it is mono so only counts as one channel). DPL can be encoded and transmitted over stereo (i.e., 2 lines, right and left) cables to a receiver that is capable of decoding the signal and outputting to all 4 channels.

Dolby Pro Logic II (DPLII). This is a 5-channel surround signal that can be sent over analog or digital devices. The 5 channels are R, L, C, Rr and Lr. DPLII also can be encoded and transmitted over stereo cables to a receiver that is capable of decoding the signal and outputting to all 5 channels.

Dolby Digital AC-3 (DD). This is usually 6 channels (termed '5.1') that is principally sent over a digital connection, such as a TOSLINK optical cable from the Mac Mini or Apple TV's optical audio port (but is currently nonfunctional on the ATV because of software limitations) to a receiver. The channels for DD are L, R, C, Rr, Lr and the low frequency LFE channel. The LFE is the '.1' channel.

You can read more about these from the pulldown at Dolby's surround sound web page.

http://www.dolby.com/resources/tech_library/index.cfm

2. Hardware

Apple TV. It has an audio chip that can decode up to a 7.1 signal. It has both optical audio out (which is capable of delivering a DD signal, but currently is not implemented) and RCA stereo jacks (which are analog and can thus deliver DPL or DPLII, but not DD, signals). The Apple TV uses Quicktime to play its video content and encoded AAC audio (which is distinct from AC-3 audio). It does not have DVD Player application that ships will all Macs.

Mac Mini. I do not know what the audio chip is inside the Intel-based Minis, but it is capable of at least 5.1 audio passthrough using its optical audio-out port (which is also a dual-function analog stereo-out port). If you connect a TOSLINK cable to it you get optical output (DD, DPLII, DPL, DS, Stereo). If you connect a 1/4" stereo to RCA cable to it you get analog (stereo, DPL, DPLII, but not DD) output. The Mac Mini can use Quicktime or DVD Player to play video content, depending on the file type.

3. Software

DVD Player. This program on the Mac Mini is capable of sending Dolby Digital AC-3 audio data through the optical port of a Mac Mini via a TOSLINK cable. It cannot send AC-3 out via a stereo-to-RCA cable. If you play a DD 5.1-encoded DVD (real or ripped to your hard drive with MacTheRipper) using DVD Player and you have a TOSLINK cable between your Dolby Digital-capable receiver and Mac Mini, DVD Player will passthrough the AC-3 info to the receiver, which will decode it into all 6 channels (L, R, C, Lr, Rr, LFE). This will give you 5.1 surround sound. If the DVD only has DPL, DPLII or 2-channel stereo, then only those can be passed through. You cannot get 5.1 surround from DPLII, DPL or stereo audio.

Quicktime Player. The program is found on the Mac Mini as well as the Apple TV. Since it cannot decode AC-3 audio files, there is currently no way to get AC-3 audio (i.e., 5.1 surround) from Apple TV to a 5.1 receiver. Quicktime is capable of encoding 6 discrete audio channels, but they are in AAC, not AC-3. Since there are no consumer receivers on the market that can decode AAC, you cannot get 5.1 surround sound from the Apple TV or Mac Mini using Quicktime. Quicktime will, however, allow the playback of stereo and since DPL and DPLII can be encoded in stereo channels you can get 4-channel (DPL) or 5-channel (DPLII) audio from your Apple TV or Mac Mini, provided they are connected to a receiver capable of decoding DPL or DPLII. (Note, though, that there is usually channel leakage in DPL and DPLII, thus separation is not as good as it is with DD.)

Handbrake. With the release of version 0.9, Handbrake (http://handbrake.m0k.org/) included the ability to convert DD AC-3 into DPLII 5-channel surround in the transcoded Quicktime video file. If you select the Apple TV preset for a DVD with 5.1 AC-3, Handbrake will convert the 5.1 AC-3 file into a DPLII stereo audio track (see "Track 1 Mix" on attached screen shot) of the H.264 output MPEG4 file and it will contain the L, R, C, Rr, and Lr channels, but not the LFE channel. If you play this on the Apple TV using a TOSLINK cable (or the RCA jacks) to connect the ATV to your DPLII-capable receiver, you will get 5-channel surround (but not 5.1 surround). Handbrake also has a provision to convert the 5.1 AC-3 audio into 6 discrete channels encoded in AAC in Quicktime; however, as mentioned above, since there are no consumer receivers on the market today that can decode AAC from Quicktime audio there's really not much point in using this feature of Quicktime. I have tried this, and it does play on my Onkyo receiver, but it is not 5.1 surround.

VLC. Handbrake can also be used to transcode DVDs into MKV format containers with H.264 video encoding and Dolby Digital AC-3 5.1 surround sound passthrough (see second attachment). These files will not play in Quicktime, thus cannot be used for playback on the ATV. However, VLC (http://www.videolan.org/vlc/download-macosx.html) will play them on a Mac and passthrough the AC-3 audio file through the optical port to a receiver using a Toslink cable. (Install Perian (http://perian.org/) for good measure.) Provided your receiver has an optical input and the ability to decode Dolby Digital, you can get 5.1 surround sound with your movies. One word of caution: VLC is very buggy and skipping ahead can cause all kinds of problems with crashing VLC, and also crashing your audio in such a way that the only fix is to reboot your Mac. In addition, these files are typically much larger than MP4 H.264 stereo/DPL/DPLII files because of the size of AC-3. A 2 gig movie with MP4/DPLII will be about 3 gigs as an MKV/AC-3.

DVD2OneX. DTOX (http://www.dvd2one.com/) is an app that will take a DVD ripped to your hard drive with MacTheRipper (http://www.mactheripper.org/) and compress it to a smaller size. One preset is to make it small enough that you can fit it on a single-layer DVD. You can use it to clone the DVD or to make a DVD for individual videos from the DVD. If you have Leopard on your Mac, Front Row will now allow you to play DVDs from your hard drive. Because of this, I have my 5.1 surround sound-intensive DVDs MTR/DTOX'd to 4.2 gig VIDEO_TS folders for playback on my Mac Mini home theater system. Its much cleaner and reliable than playback of MKV files with VLC. I have an external firewire drive with a folder called 'DVD' in which these VIDEO_TS folders are stored, and an alias to the DVD folder is copied to my Home/Movies folder. When Front Row is launched, select Movies, then drive down to the DVD folder of your choice. Of course, these ripped VIDEO_TS folders can also be played by DVD Player with passthrough of the 5.1 surround sound to your receiver, as well.

ekrem13
Sep 17, 2013, 08:20 AM
I mux my mkv files with iflicks or ivi, if original file has dts or ac3 audio, converted m4v file also supports 5.1 audio right? I get confused after recent posts claiming that these apps doesnt support surround audio ?