H.264 vs. MPEG-2 comparisions?

Hulk wrote on 6/20/2006, 5:01 PM
Last year when I wrote the two-part article on frameserving to Nero Recode 2 I believe someone in this forum was telling me that comparing H.264 and MPEG-2 is kind of like comparing apples and oranges.

H.264 was designed for lower bitrates, high compression applications while MPEG-2 was designed to be used at higher bitrates.

I'm interested in learning more about this and was wondering if anyone in this forum could provide further information?

- Mark

Comments

p@mast3rs wrote on 6/20/2006, 5:10 PM
www.doom9.org is an excellent place. Try the Mpeg-4 AVC forum.
john-beale wrote on 6/20/2006, 7:37 PM
I don't know what kind of fruit they represent but in my experience, at any given bitrate, H.264 video is clearly better quality than MPEG2. Note, I'm referring to H.264/MPEG4 Part 10/AVC as generated by the x264 codec.

See also:
http://en.wikipedia.org/wiki/H.264
http://en.wikipedia.org/wiki/X264
DJPadre wrote on 6/21/2006, 6:04 AM
in addition to jbeale's comments, i find even DivX codecs (which are also tagged as MPG4... but not of the AVC sense) are clearly CLEARLY superior to MPG
farss wrote on 6/21/2006, 6:24 AM
i was perhaps one of the people who might have maybe made the original comment.
You have to factor in that this is at very high bitrates, from memory well over 20 Mb/sec, I've seen some mpeg-2 systems speced to 100Mbits/sec for D-Cinema applications.
I used to think I knew it all, that more advanced codecs such as H.264, WMV etc were clearly superior to mpeg-2 however a Canopus engineer set me right, mpeg-1 is the best codec, followed by mpeg-2. I know that's a pretty hard to swallow pill but what he was talking about was how good it CAN be, not how good it is for day to day bandwidth constrained use.

To look at this another way. Better compression schemes are optimised to get the best possible picture (or audio) into the smallest possible bandwidth. The intention was never to make them lossless, rather it was to make them appear (or sound) lossless. Give the less complex compression schemes enough bandwidth and they can come to close to if not actually be totally lossless.

Bob.
DJPadre wrote on 6/21/2006, 9:42 AM
i hear ya Bob.. one thign abotu MPG1 ia that of al the codecs, its so damn versatile, however moving onto bitrates etc..

i recently did a HDV project and encoded it to DVD.. then i took the master AVI and ran a Divx encode at 1.5kbps

Now the DVD was a VBR 8200, 6700, 2400
the Divx was a constant 1500 for audio @160kbps and he rest was allocated to video.

to my eye, and thrown across a HD LCD projector spanning a 12 metre wall across, the divx version was far superior in colour gradation, noise, and motion. the DVD version using, Main concept, was nowhere near as "clean" looking..

Now, imagine the DIvx Stream at 25mbps... i would fathom a guess that it would be the closest to the original format than any lossey compressor could ever get..
farss wrote on 6/21/2006, 3:35 PM
Well that's the mistake I was falling into.
Certainly I'd expect at around 5Mbits/sec Divx will outperform mpeg-2. Howing the question is how well can the codec scale at higher bitrates, what are the inherent losses of the codec regardless of bitrate. I'd suspect that a DivX encode at 20 Mbits/sec will look no better than one at 5Mbits/sec.
Digital Betacam I believe uses a 2 frame GOP mpeg-2 stream at well over 100Mbits/sec and it doesn't get much better for SD than DigiBeta, that's 4:2:2 10 bit video!
DVB broadcast is also uses mpeg-2 compression at around 19 Mbits/sec, it blows the mpeg-2 on DVD out of the water.
There's another issue at play here too, the quality of the decoders and their ability to keep up at higher bitrates.

I'm not for a minutes saying that for day to day applications that mpeg-2 is better than DivX, quite the contrary. I too am very impressed with DivX compared to mpeg-2 at bitrates that I can use.

Bob.
vitalforce wrote on 6/21/2006, 3:43 PM
Excuse my ignorance on this topic, but will a set-top DVD player play a DVD not encoded in MPEG-2, such as DIVX or H.264? Or am I asking the question wrong?
farss wrote on 6/21/2006, 3:48 PM
My Sony quite happily plays DivX although not some of the latest variants. This is NOT part of the DVD spec so there's no guarantee that all or even most STBs will play DivX. I guess one arm of Sony figured they might as well make a buck out of piracy.

Bob.
Hulk wrote on 6/22/2006, 5:16 AM
Bob,

Could you explain a bit more the statement the Canopus engineer regarding MPEG-1 being the best codec? Is it that codecs are designed for a certain range of bitrates and that MPEG-1 at high bitrates somehow does very little "damage" to the source in order to compress it?

- Mark
DJPadre wrote on 6/22/2006, 11:25 AM
"Excuse my ignorance on this topic, but will a set-top DVD player play a DVD not encoded in MPEG-2, such as DIVX or H.264? Or am I asking the question wrong? "

Im using a pioneer 838 (or is that 383) i cant remember... which plays Divx MPG4... it reads divx as mpg4...
It also reads WMV8 as well as straignt MPG1, 2 and avi files without needing to author.

Ill be testing some DivX encoded HD material on the unit, but ive tried jacking it up to 1800kbps as SD DivX and it does bottleneck at anything higher than 1500... so i'll give HD Divx@1500 a go... dunno how good it will look, but i doubt it... then again i can always feed it from a laptop running at 5000... hmm...
Cunhambebe wrote on 6/22/2006, 8:22 PM
I think Xvid is clearly much better than Divx, even though mp4 (x264) is much better than both Divx and Xvid. These codecs may blow away the good and old MPEG2. Let's wait and see...
farss wrote on 6/23/2006, 1:29 AM
Basically yes, that's what I understood them to mean.
This rather intimidating document gives a pretty detailed look into the belly of the beast. Note that mpeg is speced for 4:2:2 in the Studio Profile and can (in theory) handle 4:4:4 and upto 4K resolution.

For me a simpler comparision is mp3 and PCM, at bitrates over say 192K there's not much improvement in mp3 whereas PCM just gets better the higher the sampling rate and bit depth.

I think also you need to factor in the ease of decoding at higher bitrates. H.264 seems to require a lot of grunt to decode whereas mpeg-2 seems much easier so very high bitrates mpeg would seem easier to implement than H.264.