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(Note: I used to be employed by Mozilla, and in that capacity I was the owner of Mozilla's image decoders. I've been disconnected from all decisions for almost

by joedrew 12y ago

(Note: I used to be employed by Mozilla, and in that capacity I was the owner of Mozilla's image decoders. I've been disconnected from all decisions for almost a year, though.) The main take-home here is that while Google's numbers all show WebP as being objectively better, the metrics they chose for comparison were relatively bad (i.e., some of them didn't take into account colour or didn't model colour correctly), and once you accounted for that the numbers were not nearly as good a story for WebP; in some cases, JPEG outperformed it. The facts that (1) WebP was not terribly compelling technically, (2) JPEG is already supported by everything on the web, not to mention devices and mobile phones etc, and (3) there's still headroom to improve JPEG in a backwards-compatible way, meant that WebP was (and, it seems, remains) a non-starter.

dbcooper 12y ago
I had read in the past that HEVC was probably the best for still image lossy compression. [1] Does anyone have further information on this? [1] http://en.m.wikipedia.org/wiki/High_Efficiency_Video_Coding#Main_Still_Picture http://en.m.wikipedia.org/wiki/High_Efficiency_Video_Coding#...
- sp332 12y ago
  According to the study linked in OP, it's still true. https://people.mozilla.org/~josh/lossy_compressed_image_study_july_2014/ https://people.mozilla.org/~josh/lossy_compressed_image_stud...
  - dbcooper 12y ago
    Cheers!
- derf_ 12y ago
  Best from a compression perspective, perhaps. There's the minor detail of it being patent-encumbered. There's no license pool available yet, so you couldn't pay for it if you wanted to. The proposed terms of the pool that is organizing (with some of the known patent holders refusing to join) would require up to $25mln/year for the video codec. No idea if you'd be able to get a better deal for still-images only. Meanwhile, JPEG is free.
leccine 12y ago
Could you conduct a detailed article and publish it please? I think it would be useful for people who are interested in this but don't have the background about JPEG or WEBP internals. NVM I found what I was looking for: http://people.mozilla.org/~josh/lossy_compressed_image_study_july_2014/ http://people.mozilla.org/~josh/lossy_compressed_image_study...
cromwellian 12y ago
But is there headroom for JPEG to replace animated gifs? If I look at mobile social apps these days, animated GIFs eat up enormous amounts of data. JPEG doesn't seem to have an answer for this, and no one has yet, it appears, made the <video> element work for this use case.
- jlebar 12y ago
  > no one has yet, it appears, made the <video> element work for this use case. 4chan has, and it's significant not only because they have a lot of traffic, but also because their implementation has to be pretty solid -- 4chan users would love nothing more than to troll the administrators by breaking this. http://blog.4chan.org/post/81896300203/webm-support-on-4chan http://blog.4chan.org/post/81896300203/webm-support-on-4chan
  - LaikaF 12y ago
    That and 4chan is a big content generator for the internet. Everything further down the line (reddit, imgur, 9gag, tumblr) should support it. Especially tumblr, who can consume over a gig of ram if you scroll down long enough.
  - anon4 12y ago
    >4chan users would love nothing more than to troll the administrators by breaking this Not really worth it. You'd post something once, then you'd get banned for a week. Unless you have a fleet of proxies or can keep changing ip address somehow, and can keep posting while they try to fix whatever exploit it is you found. Kind of hard to target admins when they're all anonymous, too.
    - ANTSANTS 12y ago
      If you have a dynamic IP address (most people do), getting a new IP is as simple as changing a byte in your router's MAC address.
      - nitrogen 12y ago
dvirsky 12y ago
Until JPEG supports transparency, it leaves a vast hole where a good lossy alpha enabled format is needed - namely icons. With the high resolution of mobile devices, using PNG for this use case is a huge waste. Regardless of the quality differences, WebP fills a major pain for mobile and web developers. I really think Mozilla should just support it.
- milsorgen 12y ago
  How much of a gain do you get in WebP versus a properly optimized PNG for icons? I can't imagine it's a compelling difference.
  - wodenokoto 12y ago
    Simple 2 or 3 color icons might not win a lot, but there is also a whole genre of photo-realistic icons which would have a lot to gain from WebP like formats.
    - milsorgen 12y ago
      I've been trying to pull up some data but I keep coming back to JPG v. WebP. Got a link to anything by chance?
      - ZeroGravitas 12y ago
        http://geeks.everything.me/2013/04/24/why-we-like-webp/ http://geeks.everything.me/2013/04/24/why-we-like-webp/ Suggests a 5x benefit over PNG for mobile app icons.
        milsorgen 12y ago
        I appreciate the information, thank you!
        pornel 12y ago
        Google's own marketing materials claim 25-33% improvement at the same quality, so 5x improvement suggests they didn't compare apples to apples. Comparing formats in a fair way is hard. "Looks almost the same" is a common fallacy — small change in quality can have dramatic change in file size, e.g. JPEG 80 and JPEG 90 look almost the same, but one is 2x larger than the other! For example lossy WebP doesn't support full color resolution, but JPEG by default does. If you don't correct for that you're telling JPEG to save 4x as much color, and the difference is usually imperceptible, because that's the whole point of chroma subsampling.

by joedrew 12y ago

dbcooper 12y ago

I had read in the past that HEVC was probably the best for still image lossy compression. [1] Does anyone have further information on this? [1] http://en.m.wikipedia.org/wiki/High_Efficiency_Video_Coding#Main_Still_Picture http://en.m.wikipedia.org/wiki/High_Efficiency_Video_Coding#...

sp332 12y ago
According to the study linked in OP, it's still true. https://people.mozilla.org/~josh/lossy_compressed_image_study_july_2014/ https://people.mozilla.org/~josh/lossy_compressed_image_stud...
- dbcooper 12y ago
  Cheers!
derf_ 12y ago
Best from a compression perspective, perhaps. There's the minor detail of it being patent-encumbered. There's no license pool available yet, so you couldn't pay for it if you wanted to. The proposed terms of the pool that is organizing (with some of the known patent holders refusing to join) would require up to $25mln/year for the video codec. No idea if you'd be able to get a better deal for still-images only. Meanwhile, JPEG is free.

leccine 12y ago

Could you conduct a detailed article and publish it please? I think it would be useful for people who are interested in this but don't have the background about JPEG or WEBP internals. NVM I found what I was looking for: http://people.mozilla.org/~josh/lossy_compressed_image_study_july_2014/ http://people.mozilla.org/~josh/lossy_compressed_image_study...

cromwellian 12y ago

But is there headroom for JPEG to replace animated gifs? If I look at mobile social apps these days, animated GIFs eat up enormous amounts of data. JPEG doesn't seem to have an answer for this, and no one has yet, it appears, made the <video> element work for this use case.

jlebar 12y ago
> no one has yet, it appears, made the <video> element work for this use case. 4chan has, and it's significant not only because they have a lot of traffic, but also because their implementation has to be pretty solid -- 4chan users would love nothing more than to troll the administrators by breaking this. http://blog.4chan.org/post/81896300203/webm-support-on-4chan http://blog.4chan.org/post/81896300203/webm-support-on-4chan
- LaikaF 12y ago
  That and 4chan is a big content generator for the internet. Everything further down the line (reddit, imgur, 9gag, tumblr) should support it. Especially tumblr, who can consume over a gig of ram if you scroll down long enough.
- anon4 12y ago
  >4chan users would love nothing more than to troll the administrators by breaking this Not really worth it. You'd post something once, then you'd get banned for a week. Unless you have a fleet of proxies or can keep changing ip address somehow, and can keep posting while they try to fix whatever exploit it is you found. Kind of hard to target admins when they're all anonymous, too.
  - ANTSANTS 12y ago
    If you have a dynamic IP address (most people do), getting a new IP is as simple as changing a byte in your router's MAC address.
    - nitrogen 12y ago

dvirsky 12y ago

Until JPEG supports transparency, it leaves a vast hole where a good lossy alpha enabled format is needed - namely icons. With the high resolution of mobile devices, using PNG for this use case is a huge waste. Regardless of the quality differences, WebP fills a major pain for mobile and web developers. I really think Mozilla should just support it.

milsorgen 12y ago
How much of a gain do you get in WebP versus a properly optimized PNG for icons? I can't imagine it's a compelling difference.
- wodenokoto 12y ago
  Simple 2 or 3 color icons might not win a lot, but there is also a whole genre of photo-realistic icons which would have a lot to gain from WebP like formats.
  - milsorgen 12y ago
    I've been trying to pull up some data but I keep coming back to JPG v. WebP. Got a link to anything by chance?
    - ZeroGravitas 12y ago
      http://geeks.everything.me/2013/04/24/why-we-like-webp/ http://geeks.everything.me/2013/04/24/why-we-like-webp/ Suggests a 5x benefit over PNG for mobile app icons.
      - milsorgen 12y ago
        I appreciate the information, thank you!
      - pornel 12y ago
        Google's own marketing materials claim 25-33% improvement at the same quality, so 5x improvement suggests they didn't compare apples to apples. Comparing formats in a fair way is hard. "Looks almost the same" is a common fallacy — small change in quality can have dramatic change in file size, e.g. JPEG 80 and JPEG 90 look almost the same, but one is 2x larger than the other! For example lossy WebP doesn't support full color resolution, but JPEG by default does. If you don't correct for that you're telling JPEG to save 4x as much color, and the difference is usually imperceptible, because that's the whole point of chroma subsampling.