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robrose20
Nov 26, 2007, 02:15 PM
Is there software out there that will upconvert a ripped DVD MP4 file to HD format for viewing on Apple TV? There are upconverting DVD players out there, it shouldn't be too hard.



Cave Man
Nov 26, 2007, 02:25 PM
Not that I know of. Keep in mind, the upconverters do it on the fly, so as to save hard disk space.

spice weasel
Nov 26, 2007, 02:45 PM
Can I ask why you would want to do this? You can't add resolution that isn't in the source to begin with, so all you are going to accomplish is to produce bloated files.

Why not let the television do the upconverting for you?

Help!
Nov 26, 2007, 06:14 PM
It already does this?

wmealer
Nov 27, 2007, 09:21 AM
It already does this?

If you can watch basic analog cable on your HDTV (you can), then yes. In other words, yes, all HDTVs can upconvert, because they have to.

The upconverting DVD players you mention just take the processing load off the TV, but your TV will do it if you allow it to, and most TVs do a fine job of it.

robrose20
Nov 27, 2007, 10:39 AM
My question really is, lets say you have apple TV or have your multimedia computer attached to a HD television and you are viewing content from the converter, is there software that will allow you to take a lower resolution MP4 file and upconvert on the fly to 720p or 1080p for maximal viewing on a high-def television. Does the apple TV do this? Do the HD TV's do that? It just seems like when I have seen standard def on a high def TV it has not been impressive.

I have a bunch of DVD's that I am ripping so I can store the content digitally on my Mac. I plan on getting an apple TV but will wait until jan for any possible revision. I am using Handbrake and using the standard APPLE TV settings with the addition of 2 pass encoding (turbo first pass). The output resolution is somewhere in the 720x320 range (anamorphic, etc). My TV is capable of 1080p, I would want to try to maximize the resolution or upconvert those files on the fly to try to improve image quality.

When I have seen the Apple TV in the store, the video seems grainly and of poor resolution with the demo floor model. Is there anything else I can do to improve the resolution?

Chipart
Nov 27, 2007, 11:34 AM
My question really is, lets say you have apple TV or have your multimedia computer attached to a HD television and you are viewing content from the converter, is there software that will allow you to take a lower resolution MP4 file and upconvert on the fly to 720p or 1080p for maximal viewing on a high-def television. Does the apple TV do this? Do the HD TV's do that? It just seems like when I have seen standard def on a high def TV it has not been impressive.

As the previous answers, while correct, did not seem to resonate with you, her's another try.
Let's assume you have a true HDTV with a 1920x1080 panel.
Now, if you watch a normal DVD without any upconversion by the DVD-player. Does the picture fill (a) the entire screen or (b) only the center quarter of it (to be more precisely the center 720x576 px)?
If your answer is (a) which I assume and your answer would be (a) for watching SDTV as well, ther should be some kind of upconversion invloved in your signal chain (as some "device" needs to convert the incoming 720x576 signal into the native resoultion of the panel).

For most "reasonable" uses, it is pretty insignificant, if the upconversion is done by the dvd-player, the TV, an AV-Receiver, a seperate device or elsewhere (although from a singnal processing engineering point of view I'd like to argue that any conversion should be done as late in the chain as possible)

The problem by the way is not so much, that SDTV looks ugly on a HDTV. The problem is more, that a picture in SDTV-resolution (720x576) looks ugly on any devie with a width of over 1 meter, as a single pixel becomes more than 1mm wide.

The output resolution is somewhere in the 720x320 range (anamorphic, etc). My TV is capable of 1080p, I would want to try to maximize the resolution or upconvert those files on the fly to try to improve image quality.

Once you have reduced the resolution to 720x320, no upconverter in the world can increase the real resolution of the pictures. The information is gone!

Still don't get the point? Assume, you reduce the resolution further to let's say 2x1, so that each frame is basically reduced to 2 Pixels. Each of the two pixels will typically show some shade of gray (as the average color of the entire picture should be some shade of gray). No upconverter can ever guess, if the original picture showed a car or a house! This information is gone! Forever!

When I have seen the Apple TV in the store, the video seems grainly and of poor resolution with the demo floor model. Is there anything else I can do to improve the resolution?

It was not due to the poor resolution of the demo model, but due to the poor resolution of the movie source. Therefore there's most likely nothing you could do to improve this.

Yours,
Chip

iqvworld
May 21, 2010, 08:56 PM
Chip,

The guys question was valid and I have the same question. Your answer is true, that the native resolution is the native resolution, we all get it. His question was is there anything that can upconvert the content of a ripped MP4 by on-the-fly resampling of the image to 1080i or 1080p similar to what the newer DVD players can do.

You statement that most TVs can do that is factually incorrect. I have yet to see a TV that can universally take a source and resample it on the fly. It stretches the pixels and it's very unsightly.

So if anyone actually has an answer that would be great, because I am interested as well as the original poster of this thread. I am using Apple TV, so I'd specifically like to learn about that. I would also consider running the files through an upconverter program that resamples them to a higher resolution if that's the only option that I have. Appreciate any thoughts.

Jim

brentsg
May 21, 2010, 10:41 PM
Wow.. you guys don't get it.

The newer DVD players you mention aren't doing anything fundamentally different than your TV. Some may do it differently, or better, or worse. But they are all utilizing various techniques to try making the best of ****** sources.

By "stretching pixels" I assume you are referring to techniques that attempt to fit 4x3 content onto a display that is 16x9. Obviously that adds some additional challenges.

So no, it still wasn't a good question.

iqvworld
May 22, 2010, 12:30 AM
Ok, let's just go with I'm a moron. So, if you can take time out of your day to continue to reply with this moron it would be appreciated. The facts: I have a DVD I own. It's in a 16:9 aspect ratio, but it's resolution is say 854x480. That resolution natively on my 1080p resolution TV would show up filling a small part of the screen. So, what my Apple TV does is try to make it fit edge to edge. The technique it uses is ok, however, it's not as good as the DVD in the upconverting DVD player that I have. It's visually less superior.

My moronic understanding is that the "upconverting" techniques involve expanding the resolution of the DVD content to 1920 x 1080 (or 1280 x 720) and then filling in the "extra space" using something akin to a bi-cubic or bi-linear mechanism. Now as far as I know, all of the televisions I've seen do not support this type of scaling. I thought that the individual pixels were enlarged, in most cases, to get to the resolution.

Again, but I "just don't get it". If you don't have an answer then please just **** and let someone who does answer it instead of trying to educate the morons.

fpnc
May 22, 2010, 02:39 AM
The Apple TV upscales (or downscales) on all of its sources depending upon the resolution you set for Apple TV's output. You can set the output to 480p, 720p, 1080i, or 1080p. Given the aspect ratio in the source, the Apple TV will scale the image to make as much use of the TV's full screen area as possible.

If you are seeing marked differences between your DVD's upscaling and that done by the Apple TV the problem is most likely in your transcoding from the DVD to the H.264 container (file) that you need for playback on the Apple TV. That said, you'll never get a perfect transcode from the DVD so the DVD will always look better (with a few rare exceptions, depending on things like interlacing and pull-down which might actually be better done in software during the transcode rather than in hardware on the DVD player).

If you've hacked your Apple TV to play MPEG2/VOB containers directly then you are no longer using Apple's codecs and all bets are off as far as performance and quality (i.e. you can't really blame the quality differences directly on the Apple TV since you have third-party codecs running that may not even make use of the hardware-based decoding and scaling that is available in the Apple TV's GPU).

My advice would be to let the Apple TV do the scaling and just encode your DVD rips at the same resolution as on the DVD itself (taking into consideration the anamorphic setting on the DVD and the respective anamorphic treatment when you transcode using Handbrake or QuickTime).

brentsg
May 22, 2010, 11:03 AM
My moronic understanding is that the "upconverting" techniques involve expanding the resolution of the DVD content to 1920 x 1080 (or 1280 x 720) and then filling in the "extra space" using something akin to a bi-cubic or bi-linear mechanism. Now as far as I know, all of the televisions I've seen do not support this type of scaling. I thought that the individual pixels were enlarged, in most cases, to get to the resolution.


The comments on the TV's scaling capabilities really depend on the quality of the display. I know my Pioneer handles scaling every bit as well as any upscaling DVD player. One of my players uses a Silicon Optix Reon-VX chip for image processing and it might do a marginally better job, but I wouldn't expect most people to be able to discern a difference.

The bottom line is you should probably check the quality of your encodes. It's possible that's where the issue is. It wouldn't make sense to bloat your encoded files with interpolated data, and waste the encoding time as well. That shouldn't be necessary either.

The 480p encodes that I play on my plasma via a Mac Mini look nice. You won't confuse them with HD material but they look no different than the same content played via DVD from a PS3 (regardless of whether I let the TV or the PS3 do the scaling).