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From my limited experience, it could probably be better than MPEG-2 with quality, if encoded properly. There is the catch. Encoding takes a lot of time.


The quickest encoder is AVIVO Video Converter. Most die-hards didn't like it, as it uses the simpliest profiles of H264 specification.


But I tested a 1920x1080 5 minute clip and it did it in 10 minutes, what Divx and XVID (single pass, not even H264 encoders) took 20-30 minutes. To my eyes it looks better than most DIVX encodes I have done, and equal to some of my better XVID encodes, using a lot less time.


Also the other catch is playback takes a lot more horsepower. My system can't playback the 1920x1080 clip I spoke of, it can play back 1280x720 clips fairly easily, and downloaded trailers 1080p from Apple site, which I think are H264, play at the peak of my system, but no skipping.


I'm using CoreAVC which is the most efficient decoder, unless you get a video card with hardware help. I think ATI requires X1000 series and they recommend X1800 or better for 1080p H264. This then requires proper drivers and Cyberlink decoder I think which works with the card. Nvidia has similar setup for certain cards.


If anybody knows a way I can simply downres my 1920x1080 to 1280x720 and put it back into MPEG2 so I can then convert in AVIVO, I would be thankful.


Also another downside is editing it or other MPEG-4. I don't know of a program (i.e. VideoRedoPlus), that can edit MPEG-4 material like VDRPlus does with MPEG-2.


But I wouldn't mind archiving to that format to save space, as the quality looks pretty good to me.


I think PS3 can play this format, PSP and IPOD do (specific formats required). I don't think XBox360 can play H264 as an extender but can play it off of HD-DVD.
 

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Quote:
Originally Posted by jpconard /forum/post/0


From my limited experience, it could probably be better than MPEG-2 with quality, if encoded properly. There is the catch. Encoding takes a lot of time.


The quickest encoder is AVIVO Video Converter. Most die-hards didn't like it, as it uses the simpliest profiles of H264 specification.


But I tested a 1920x1080 5 minute clip and it did it in 10 minutes, what Divx and XVID (single pass, not even H264 encoders) took 20-30 minutes. To my eyes it looks better than most DIVX encodes I have done, and equal to some of my better XVID encodes, using a lot less time.


Also the other catch is playback takes a lot more horsepower. My system can't playback the 1920x1080 clip I spoke of, it can play back 1280x720 clips fairly easily, and downloaded trailers 1080p from Apple site, which I think are H264, play at the peak of my system, but no skipping.


I'm using CoreAVC which is the most efficient decoder, unless you get a video card with hardware help. I think ATI requires X1000 series and they recommend X1800 or better for 1080p H264. This then requires proper drivers and Cyberlink decoder I think which works with the card. Nvidia has similar setup for certain cards.


If anybody knows a way I can simply downres my 1920x1080 to 1280x720 and put it back into MPEG2 so I can then convert in AVIVO, I would be thankful.


Also another downside is editing it or other MPEG-4. I don't know of a program (i.e. VideoRedoPlus), that can edit MPEG-4 material like VDRPlus does with MPEG-2.


But I wouldn't mind archiving to that format to save space, as the quality looks pretty good to me.


I think PS3 can play this format, PSP and IPOD do (specific formats required). I don't think XBox360 can play H264 as an extender but can play it off of HD-DVD.


hjsplit software can at least split it up, etc. thx forthe info
 

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Quote:
Originally Posted by JoeFigueiredo /forum/post/0


...over MPEG2.

The most simple answer is no, it does not. What it (as well as VC-1) does, is allow the same quality at lower bitrates, or higher quality at the same bitrate (assuming MPEG-2 was starved). Of course that is assuming that the encodes for each codec are made from a pristine source and each is encoded for the same quality (as each other) at the lowest bitrate possible. Any of these codecs can achieve "transparency", the only difference between them is how many bits it takes to get there.


Take for example Blu-ray, with that essentially you're not limited by space. It's quite possible to make "perfect" encodes of a movie with any of the supported codecs, MPEG-2, H.264, or VC-1. The only difference is the H.264 and VC-1 versions would be significantly smaller.


Now it quickly gets more complicated, for example take satellite HD, "HD Lite", this is MPEG-2 at about 10-12 Mbps. These are not "transparent" have lots of artifacts, and are often/usually 1280x1080 instead of full 1920x1080. In such a case, switching to AVC (or VC-1) at the same bitrate would result in higher quality. Of course the could also switch to AVC and lower the bitrate and end up with the same. By comparsion, HD DVD is running VC-1 at ~12Mbps and achieving full 1920x1080 and transparency to the master (artifact free).


One last situation, transcoding, which may be what you're thinking of. Converting from one lossy codec to another can only go in one direction (quality wise), down. The best you can get in this situation is transparency to the MPEG-2 source. Transcoding an MPEG-2 recording to AVC may end up smaller but will probably be worse in quality as well, it definitely won't be better.
 

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Quote:
Originally Posted by stanger89 /forum/post/0


Now it quickly gets more complicated, for example take satellite HD, "HD Lite", this is MPEG-2 at about 10-12 Mbps. These are not "transparent" have lots of artifacts, and are often/usually 1280x1080 instead of full 1920x1080. In such a case, switching to AVC (or VC-1) at the same bitrate would result in higher quality. Of course the could also switch to AVC and lower the bitrate and end up with the same. By comparsion, HD DVD is running VC-1 at ~12Mbps and achieving full 1920x1080 and transparency to the master (artifact free).


.


and this is the main problem , many of us knew from the beginning .


H. 264 is getting more and more an "ALIBI" codec to distribute freeely socalled High Definition crap channels".

Here in Germany these cable or dvb/s HD channels started with bitrates of up to 20 Mbit in MPEG2 1920x1080 and acceptable quality .


Then the first commercial HD chanels appeared in dvb/ s2 and H.264 . Bitrates were quite acceptable in the 8- 9 Mbit range .


Now ..... you know the laws of the market ?


yes ... you know ....quite appealing not to stuck with 2 or three channels on one of the not so cheap Astra transponders..

lets start another sale - xxx- or lala channel .... same transponder , and short after another one .


look mam ..isn`t it easy..lets just lower the bitrates ..we got 2 million subscribers


last week I saw a H.264 DVB/s 2 stream in 1920x1080 resolution with low peaks of 4 and high peaks of 6,5 MBit ...



we warned everybody 3 years ago....
 

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Yeah, unfortunately the content providers seem to be using H.264 to provide a greater number of mediocre quality channels rather than improving the image quality of their lineup. I canceled DirecTV rather than switching to their new H.264 HD DVR, but from what I've heard their MPEG-4 channels look pretty lousy as far as HD goes. D* is even bragging in their commercials about how many HD channels they plan to add (conveniently failing to mention they'll mostly be local networks to cover the all the markets they have customers in).


It used to be satellite offered better picture quality than cable, but having recently switched I can tell you that in my area digital cable is better than satellite (for now, anyway).
 

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Quote:
comparsion, HD DVD is running VC-1 at ~12Mbps and achieving full 1920x1080 and transparency to the master (artifact free).

I think they're encoded higher than that, just look at the file sizes now that rips are showing up, most are in the 25-30GB range for a 2 hour movie.
 

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Quote:
The most simple answer is no, it does not. What it (as well as VC-1) does, is allow the same quality at lower bitrates, or higher quality at the same bitrate (assuming MPEG-2 was starved). Of course that is assuming that the encodes for each codec are made from a pristine source and each is encoded for the same quality (as each other) at the lowest bitrate possible. Any of these codecs can achieve "transparency", the only difference between them is how many bits it takes to get there.

Yes but isn't the H264 specification more advanced than the MPEG-2 specifications so that it should be possible to take the original high quality uncompressed source and end up with a better quality output in H264 than would be possible in MPEG-2?


I'm not taking into consideration size, bitrates, etc. I thought block sizes, and other "features" of the H264 specification would allow for better quality.


In other words the H264 specification is supposed to be more advanced not just with compression but with quality as well?
 

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Quote:
Originally Posted by jpconard /forum/post/0


Yes but isn't the H264 specification more advanced than the MPEG-2 specifications so that it should be possible to take the original high quality uncompressed source and end up with a better quality output in H264 than would be possible in MPEG-2?


I'm not taking into consideration size, bitrates, etc. I thought block sizes, and other "features" of the H264 specification would allow for better quality.


In other words the H264 specification is supposed to be more advanced not just with compression but with quality as well?

For a given bit-rate yes, you can do much better than MPEG-2 with H.264 (or even VC-1). But if bitrate is unlimited you can produce MPEG-2 that's essentially indistinguishable from the original source. The problem is, bitrate is never unlimited. Even with the new HD-DVD/BD formats you don't have enough to space to be completely unconcerned about bitrates.
 

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Quote:
Originally Posted by jpconard /forum/post/0


Yes but isn't the H264 specification more advanced than the MPEG-2 specifications so that it should be possible to take the original high quality uncompressed source and end up with a better quality output in H264 than would be possible in MPEG-2?


I'm not taking into consideration size, bitrates, etc. I thought block sizes, and other "features" of the H264 specification would allow for better quality.


In other words the H264 specification is supposed to be more advanced not just with compression but with quality as well?

Perhaps in theory, but in practice, given unlimited bitrate, both MPEG-2 and H.264 can achieve "perfect" quality.


If bandwidth and storage capacity weren't issues it's unlikely H.264 would have been developed, or at least that it would be a "start" like it is.


But in the real world where bandwidth and storage capacity are issues, H.264 offers real advantages over MPEG-2 in that it can be transparent in situations where MPEG-2 is not, or it can be used to free bandwidth vs MPEG-2.
 
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