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VP8 and H.264 Codecs Compared In Detail
An anonymous reader writes "Moscow State University's Graphics and Media lab have released their sixth MPEG-4 AVC/H.264 video codecs comparison. Also of note is a recently added appendix to the report which compares VP8, x264, and Xvid. The reference VP8 encoder holds its own against x264 despite the source material offering x264 a slight advantage. The VP8 developers comment in the report: 'We've been following the MSU tests since they began and respect the group's work. One issue we noticed in the test is that most input sequences were previously compressed using other codecs. These sequences have an inherent bias against VP8 in recompression tests. As pointed out by other developers, H.264 and MPEG-like encoders have slight advantages in reproducing some of their own typical artifacts, which helps their objective measurement numbers but not necessarily visual quality. This is reflected by relatively better results for VP8 on the only uncompressed input sequence, "mobile calendar."'"
Input content *will* usually have been compressed with H264. Even the likes of Google will find itself transcoding 99% of its content into VP8 from some other codec. That might suck for comparison tests but its a fact of life.
One is an extorsion accessory, the other is not (yet).
Unfortunately their statement is very misleading considering how VP8 and H.264 and other MPEG codecs use basically the same transform so their statements of bias against VP8 ring untrue. One of the professors who was part of doing this test even confirmed that the VP8 developers statement was untrue and misleading.
"The reference VP8 encoder holds its own against x264 despite the source material offering x264 a slight advantage."
Um, sure, if VP8 on its "best" preset being roughly equivalent to x264 on its "high speed" preset means it's holding its own, I guess that's a fair statement.
Then that reflects the real world. Most footage that a person shoots will be compressed anyway (during recording or in editing). The fact that VP8 still looks good after the recompression tells me that we have a real winner.
I don't understand the "VP8 holds its own against x264".... The graphs show that it certainly does not hold it's own against x264. For example, if you look at the best quality settings of x264 vs VP8 for the Ice Age clip, at the same quality (SSIM=0.97), x264 takes 800Kbps while VP8 takes ~1.2Mbps... So VP8 takes 50% more bits to achieve the same quality. This shows that VP8 is not nearly as efficient as x264. (Also, note that x264 is only one implementation of an H.264 encoder. There are other implementations that will make different tradeoffs to get better compression efficiency at the cost of performance).
Since when did "near enough" become "good enough"? We might as all switch to Windows...
Most video material comes, originally, from a camera of some sort. (Obviously, this isn't the case for animation.) All of the HD camera systems I know of record in H.264, MPEG-4 or MPEG-2. (It might be called HD-DV or something else, but it's MPEG compressing under the hood.) So, if that gives H.264 an advantage, there isn't much that can be done about it. It will take a long time to replace all of the camera gear out there...
I was under the impression that there is no standard for encoding a video stream, and that the standard is in the decoding of the stream.
It makes it unlikely that this comparison of codecs shows the full potential of one standard over another - and I would be wary of drawing any conclusions.
...Which brings us back to the "for now" part of the comment.
If you're a camcorder manufacturer, chances are you're using H.264 (and paying licensing fees to do so) precisely because it's convenient for people to upload to YouTube and otherwise muck with the video without having to transcode it. If that changes because YouTube and other mainstream sites and software support VP8, and you have the ability to offer consumers the option of doing the same thing without paying licensing fees by encoding in VP8, you'll likely do so to increase your profit margin.
Your logic here supports the chicken-and-egg scenario that MPEG is praying for: manufacturers unwilling to support a format not in common use, and a format won't get in common use because manufacturers won't support it. As Google and other companies break the cycle by convincing people that the format will come into common support, manufacturers will be more willing to jump on board, bringing consumers with them.
While most of the card ones are AVCHD which is H.264, HDV cameras are MPEG-2. They are quite popular as there's reason to want tape as a storage medium.
Then of course in terms of pro video, it is still compressed, raw video is just too daunting to store, but again with different codecs. They are often takeoffs of DV where there is just very light per frame compression as well as chroma downsampling. That offers better quality on subsequent recompression and editing, as well as lower hardware requirements to encode.
This idea that everything will be H.264 as a source is inaccurate. It is popular no doubt, and I believe it will continue to be, but it isn't universal and probalby won't be.
The manufacturer's license for H.264 is $0 - for sales of 100,000 units or less each year.
For personal use only. And why on earth are you assuming that prices won't increase substantially when the MPEG-LA cartel, with no competition by your reasoning, decides it might be profitable?