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BORIStheBLADE
Jun 15, 2008, 11:22 PM
So I have a Apple Tv I'm trying to convert my DVD's to a file that can pass the 5.1 AC-3 surround sound through the digital cable to my receiver.

Right now the only way I can get it to play one the way I like is by using Handbrake. I use the H.264 encoder which saves it as a .M4V and keeps the audio track in AC3. I have a clip from a movie so my conversions are short so I don't have to waist time with test.

I end up with a file that looks like this.

General
Complete name : C:\Users\mike\Desktop\cars1.m4v
Format : MPEG-4
Format profile : Base Media / Version 2
Codec ID : mp42
File size : 60.4 MiB
Duration : 7mn 54s
Overal bit rate : 1070 Kbps
Encoded date : UTC 2008-06-15 16:02:45
Tagged date : UTC 2008-06-15 16:11:07
Writing application : HandBrake 0.9.2 2008022300

Video
Format : AVC
Format/Info : Advanced Video Codec
Format profile : Main@L5.1
Format settings, CABAC : Yes
Format settings, ReFrames : 1 frame
Codec ID : avc1
Duration : 7mn 54s
Bit rate mode : Variable
Bit rate : 621 Kbps
Width : 720 pixels
Height : 400 pixels
Display aspect ratio : 16/9
Frame rate mode : Variable
Frame rate : 23.976 fps
Minimum frame rate : 23.976 fps
Maximum frame rate : 23.988 fps
Colorimetry : 4:2:0
Scan type : Progressive
Bits/(Pixel*Frame) : 0.090
Stream size : 35.1 MiB
Writing library : x264 core 58 svn-736M
Encoding settings : cabac=1 / ref=1 / deblock=1:0:0 / analyse=0x1:0x111 / me=hex / subme=4 / brdo=0 / mixed_ref=0 / me_range=16 / chroma_me=1 / trellis=0 / 8x8dct=0 / cqm=0 / deadzone=21,11 / chroma_qp_offset=0 / threads=3 / nr=0 / decimate=1 / mbaff=0 / bframes=0 / keyint=240 / keyint_min=24 / scenecut=40(pre) / rc=crf / crf=25.5 / rceq='blurCplx^(1-qComp)' / qcomp=0.60 / qpmin=10 / qpmax=51 / qpstep=4 / ip_ratio=1.40
Encoded date : UTC 2008-06-15 16:02:45
Tagged date : UTC 2008-06-15 16:11:07

Audio
Format : ac-3
Codec ID : ac-3
Duration : 7mn 53s
Bit rate mode : Constant
Bit rate : 448 Kbps
Channel(s) : 2 channels
Sampling rate : 48.0 KHz
Resolution : 16 bits
Stream size : 25.3 MiB
Encoded date : UTC 2008-06-15 16:02:45
Tagged date : UTC 2008-06-15 16:11:07



Now when I look at that info I see only 2 channels, but when I play it on the AppleTv my receiver shows a digital audio signal and says it Dolby digital 5.1.

So if it is only 2 channel how am I getting DD 5.1?

thanks



dynaflash
Jun 16, 2008, 08:17 AM
Trust me, you *are* getting all of the dolby d goodness. The pcm stream simply announces itself as 2 channels. In Quicktime you can see all six channels if you use "SHow Movie Properties" and click on the surround audio track at the top, then at the bottom there is a tab which shows the six channels and their mapping. This is exactly the same scheme as the ATV HD movies from apple.

BORIStheBLADE
Jun 16, 2008, 06:51 PM
Trust me, you *are* getting all of the dolby d goodness. The pcm stream simply announces itself as 2 channels. In Quicktime you can see all six channels if you use "SHow Movie Properties" and click on the surround audio track at the top, then at the bottom there is a tab which shows the six channels and their mapping. This is exactly the same scheme as the ATV HD movies from apple.


Ok, as long as it isn't the fake surround sound I'll be happy.

thanks