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WebP, a new image format for the Web (The Chromium Blog)WebP, a new image format for the Web (The Chromium Blog)Posted Oct 1, 2010 12:20 UTC (Fri) by varenet (subscriber, #19900)Parent article: WebP, a new image format for the Web (The Chromium Blog)
Well, it seems Dark Shikari begs to differ, regarding quality comparisons between JPEG, H264 and WebP...
http://x264dev.multimedia.cx/?p=541
He has nice explanations as to why what's what...
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WebP, a new image format for the Web (The Chromium Blog) Posted Oct 1, 2010 17:24 UTC (Fri) by dlapine (guest, #7358) [Link]
He's also just a bit oversensitive to visually perceptive differences on his sample photos.
At first glance, looking at both side by side, no noticeable difference. Then, by doing a tab switch on the browser, I began to notice some blurriness in colored areas, but only after close examination.
His other points about lack of functionality are more relevant.
WebP, a new image format for the Web (The Chromium Blog) Posted Oct 3, 2010 11:41 UTC (Sun) by ab (subscriber, #788) [Link]
Grass is hugely different in his frame from the movie taken with analogue camera.
WebP, a new image format for the Web (The Chromium Blog) Posted Oct 4, 2010 14:08 UTC (Mon) by fb (subscriber, #53265) [Link]
FWIW IMO the faces of the two first persons look a lot better at the vp8 image than at the x264.
WebP, a new image format for the Web (The Chromium Blog) Posted Oct 8, 2010 13:56 UTC (Fri) by job (guest, #670) [Link]
I believe the point here is not which format is the best performing, but it it does not compare favorably to JPEG. Even if it does for some material chances are that the differences are slight. It is simply not good enough to replace the old, well understood, well implemented, JPEG.
WebP, a new image format for the Web (The Chromium Blog) Posted Oct 3, 2010 13:58 UTC (Sun) by Velmont (guest, #46433) [Link]
It's been updated, and shows the newest Theora Ptalabvrom actually beating VP8! Which is quite amazing given the tight constraints of the Theora format.
I never stopped loving Theora. I still use it for all my video-on-web. WebM is just slower and doesn't bring any benefits at all.
WebP, a new image format for the Web (The Chromium Blog) Posted Oct 5, 2010 12:49 UTC (Tue) by bawjaws (guest, #56952) [Link]
From an earlier post of his, titled "How to cheat on video encoder comparisons" Dark Shikari points out that he sometimes uses specific clips to highlight certain features of codecs.
http://x264dev.multimedia.cx/archives/472
He specifically mentions (in Subtle Cheating, item d.) using "parkrun" as a good test clip for adaptive quantization, one that he specifically tuned for. In the post you link to he is using a frame from the very similar "parkjoy" clip to make the same point about the existing WebP encoder (i.e. not the format)'s current lack of adaptive quantization. But, as he says:
"... claiming that either is representative of most real content and thus can be used as a general determinant of how good encoders are is of course insane."
The subtlety of his argument (in both this and his WebM review) seems to have been lost on many people and so this insanity has become common with his stills being widely touted as proving that WebP/M looks "crappy".
Despite his seeming annoyance at WebP, he himself was previously suggesting a still image format based on H.264 frames would be a good idea. Since he's also pointed out that WebM (and therefore WebP) is essentially an H.264 clone, it can't be that far away from what he suggested could be done with current H.264 tech, claiming it would beat JPEG by 2x or more (see para beginning "JPEG2000 is a classic example"):
http://x264dev.multimedia.cx/archives/472
The article is actually about the problems with wavelet compression and why JPEG 2000 and Dirac are struggling to live up to their potential, but the comment thread in particular is interesting as you get to see all the various WebP rivals (JPEG2000, JPEG-XR, DLI) that are currently being touted as obviously better than WebP being roasted for generally not being as good as JPEG (or alternatively so compute intensive that "you can fry an egg on your desktop") by random compression nerds many months before Google made it a political battle by actually implementing and releasing something that has a vague chance of adoption.
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