[joedrew]

(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.

[dvirsky]

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.

[pornel]

There are a few ways of making fully backwards-compatible "lossy" PNG: http://pngmini.com/lossypng.html

You can have icon files 3-4 times smaller, and large photorealistic images 2 times smaller than the regular PNG.

[ZeroGravitas]

The hover effect on your demo images confused me.

I assumed it would switch between the original and the compressed version. Instead it's swapping out the background to demonstrate transparency, which could probably be made more obvious.

[cpncrunch]

Also you can use svg, which is supported by the current versions of all browsers today, and the files will likely be smaller than webp, jpeg or png.

[dvirsky]

Rendering icons as SVGs is pretty horrible in terms of performance on mobile devices.

[panzi]

Yeah, depending on the image putting a bmp into a zip is actually significantly smaller than a png. Well, bmp has no alpha channel, but just as comment to the size of pngs. pngs even uses the zip algorithm in a way that is supposed to be optimized for images, but apparently it is not. E.g. the tiles here are a lot smaller as bmp in a zip: http://panzi.github.io/mandelbrot/

Ok, it put them into one single zip and can't remember if it was solid or not, so it might be the cross-file compression that makes the major difference here.

[DanitaBaires]

> Well, bmp has no alpha channel

BMP have formats which support 1-bit and 8-bit alpha channels http://en.wikipedia.org/wiki/BMP_file_format. Just open any file in Photoshop and save as BMP then click advanced. Not sure of browser support.

[FooBarWidget]

What? I thought zip and png use the same compression algorithm.

[pornel]

They do indeed.

If you're seeing BMP+ZIP being smaller than PNG it only means your PNG encoder is poor. This can be easily fixed with a PNG optimizer like Zopfli, AdvPNG or OptiPNG.

[ajslater]

I've had the best luck using opitpng and then pngout.

https://github.com/ajslater/picopt ...will do this automatically for you.

Pictopt: A multi-format, recursive, multiprocessor aware, command line image optimizer utility that uses external tools to do the optimizing.

For an all in one GUI for Mac approach to this, try ImageOptim

[imaginenore]

PNGOut is definitely better than OptiPNG most of the time:

http://www.olegkikin.com/png_optimizers/

[Hello71]

zopfli: not a png optimizer.

[chadaustin]

Well, zopflipng is! https://code.google.com/p/zopfli/source/browse/README.zopfli...

[panzi]

Yes, I even mentioned that.

[pippy]

Plus with chrome already supporting it, WebP has ~50% market share in most countries.

Now we'll have two similar but competing technologies and web developers will simply resort to the older formats.

[pornel]

One browser is not enough. Image formats have massive network effects — people want to share, save and remix images. You need support the format in image viewers, editors, file browsers, mobile apps, websites.

As an exercise, try having your avatar only in the WebP format and see how useful it'll be.

[izacus]

WebP is mostly handled via transparent proxies - meaning people with proper browsers and Android mobile devices get WebP (large market share), everyone else gets (larger) PNGs.

That way you don't really care either way on the backend.

[JohnTHaller]

Saying 'proper browsers' gives away your bias there, since only the Blink WebKit engine supports it (Chrome/New Opera), which is under 20% of the desktop market worldwide.

[cbhl]

Saying 'desktop market' gives away your bias there too.

[JohnTHaller]

Chrome has approximately the same worldwide market share as Firefox on the desktop. Both put together are eclipsed by IE. The metrics that disagree with this stat measure 'hits' (aka pre-2000 web metrics) instead of 'visitors'.

[milsorgen]

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]

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]

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]

http://geeks.everything.me/2013/04/24/why-we-like-webp/

Suggests a 5x benefit over PNG for mobile app icons.

[pornel]

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.

[milsorgen]

I appreciate the information, thank you!

[dbcooper]

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#...

[derf_]

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.

[sp332]

According to the study linked in OP, it's still true. https://people.mozilla.org/~josh/lossy_compressed_image_stud...

[dbcooper]

Cheers!

[cromwellian]

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.

[mbell]

> no one has yet, it appears, made the <video> element work for this use case.

Gfycat seems to be getting more and more popular or at least I'm personally starting to see a lot more of their links in place of imgur gif links.

http://www.gfycat.com/

[dublinben]

There's also a similar site[0] which is open source, so you could deploy it yourself if you wanted to.

[0]https://mediacru.sh/

[scrollaway]

I really wish people on HN stopped linking to gfycat and linked to mediacrush instead. The former seems like a very scummy "lowest common denominator" type of site, while the latter is open source, allows self-hosting, has deterministic hashes, uses strong https encryption, ...

[mbell]

I looked over mediacru.sh and unless I'm missing something it doesn't serve the same purpose as gfycat. The point of gfycat is to upload a gif, it converts it to webm then it gives you a bit of embed code that will try to use the webm variant but will fall back to the gif when unsupported. I didn't see anything in mediacru.sh's code that would allow gif <-> video conversion, I tried uploading a few gifs on their site as well and didn't get any video options back from the API.

[dbcooper]

Mediacru.sh should give you a "view as html 5" option. It did for me when I uploaded a gif a few minutes ago.

[untog]

It would be better if the iPhone would play <video> tags without user interaction. I get the reason why they disabled that back when the iPhone first came out, but GIFs use up more bandwidth than videos, so they're actually punishing users.

[zgohr]

Disagree. On the consumer side, I care more about auto-playing audio than bandwidth. On the content owner side, I only want my videos to autoplay (in most circumstances) if it were accompanied by the audio. If I didn't care about audio accompaniment I can already use GIF.

[untog]

Perhaps the iPhone should autoplay videos, but muted until you hit a speaker icon (or something). Either way, forcing everyone to use GIF is horrible because of how inefficient it is.

[maxerickson]

I'd like a global option and also some simple per site UI.

This is how the click to play in Firefox works, it's nice. One thing I haven't figured out how to do is trust embeds from a site (for example, Youtube and Vimeo both have well behaved embeds, so I'd like to whitelist them, but not many of the third party sites I see them on).

[syncsynchalt]

Agreed, I think of this as the "Vine" model of interaction and it's what I'd prefer. Plus leave off the icon if the webm video has no audio track.

[pornel]

That's only a UI issue. You don't need compression to be horribly inefficient to achieve that :)

For example <img src=vid.mp4> could autoplay looped video without audio, just like GIF, except using tiny fraction of bandwidth and CPU (thanks to HW acceleration) than GIF.

[rasz_pl]

this will autoplay no problem on iphone

http://phoboslab.org/log/2013/05/mpeg1-video-decoder-in-java...

:)

[mmastrac]

Expanding on Ray's comment above, this is really the compelling use case for WebP: a better container that does it all. Right now we have PNG, GIF and JPEG for three different use cases: animation, transparency and lossy encoding.

I can't easily pick and choose which of these I want, which means that we end up with 20MB GIFs that could easily be 1/5 the size, and crazy hacks to get lossy images working with transparency.

This is particularly painful for HTML5 gaming in my previous experience. For one of my projects that involved a giant, high-res game board with transparency (Nick's online Pai Sho), I ended up manually slicing the board up, converting center pieces to JPEG and leaving the edges in PNG. The images are all pasted together to make the final, seamless experience. What a PITA!

[jlebar]

> 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

[LaikaF]

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]

>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]

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]

It's probably the modem's MAC that matters for cable, and that is probably tied to the account.

[ANTSANTS]

I have a cable internet connection and know the difference between a modem and a router. You'll have to take my word for it that every time I change my router's MAC address, my public IP does as well.

[infogulch]

Yes, no one except for Twitter: http://mashable.com/2014/06/20/twitter-gifs-mp4/

[scrollaway]

And MediaCrush: https://mediacru.sh/

[joedrew]

Honestly, animated GIF (like all other image formats) is a terrible format for video-style stuff. It's fine for line art (well, sort of fine, anyways), but if you actually using it for video you really should be using <video>, because it takes into account temporal information. (gfycat is a service based around this already.)

It might be possible to do an APNG-style backwards-compatible animated JPEG, but it'll still be worse at it than video formats will be.

[TheZenPsycho]

Thanks to the ACID3 test, all modern browsers support animation in SVG and svg in an img tag. Which means you can do extremely small vector based animations, or write an encoder that embeds jpegs and animates them like a film strip. You can have alpha transparency using a mask image via SVG filters. You can get really fancy and animate with deltas. The efficiency you lose by the base64 encoding is regained by gzipping.

[ygra]

But only animation via script, not declarative animation.

[TheZenPsycho]

yes declarative animation. That is a specific test in acid 3 and you need declarative animation in svg to pass 100 on that test.

script animation is actually not supported when svg is used from an img tag. only declarative.

[magicalist]

Actually SMIL (the declarative way to do animation with SVG, for those who don't know) has always been controversial (as far as I know, IE never passed that part of Acid3), is more or less on the chopping block as far as browsers are concerned, wasn't extensively tested in the original Acid3, and, in any case, was removed from Acid3 as of 2011[1]

[1] https://plus.google.com/+IanHickson/posts/JdHnqpuUER4

[TheZenPsycho]

and yet in spite of this http://caniuse.com/#search=smil

Where have you heard or read that it is on the chopping block?

[ama729]

APNG (https://en.wikipedia.org/wiki/Apng) is the answer, but Chrome doesn't support natively.

[fournm]

Webm's definitely been getting some traction as a replacement, if 4chan's support is anything to go by.

[k__]

How trivial/fast is it to encode gif to webm?

I see many "big" webm videos on 4chan, much bigger than gifs. (in dimensions, not in bytes) and they are still smaller (in bytes) than the (dimensionally) smaller gifs.

Wouldn't it bring a huge traffic shrink, if every uploaded gif was converted to a, probably, tiny webm?

[u124556]

That's what twitter does.

[InclinedPlane]

Twitter now routinely auto-converts animated gifs into embeded web video.

[rasz_pl]

you can use javascript mpeg1 decoder instead of <VIDEO> you get auto playing animated mpeg files instead of gif mpeg is pretty much jpeg stream with bonus I frames

https://github.com/phoboslab/jsmpeg

example:

http://phoboslab.org/log/2013/05/mpeg1-video-decoder-in-java...

[coldtea]

>If I look at mobile social apps these days, animated GIFs eat up enormous amounts of data.

In mobile apps? Are they really animated GIFs?

[est]

mjpeg? It's used in many DC/DV.

We need a copy-pastable, mute by default <video> format to replace GIFs.

[duskwuff]

Motion JPEG is arguably even worse than GIF. It's literally just a sequence of JPEG images -- there's no extra compression; 100 frames of MJPEG are 100 times larger than a single image. GIF is a bad format for videos, but at least it can try to be more efficient than this.

[leccine]

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...