* Lossy compression with alpha channels. * Efficient lossless compression of photo-like images. * Efficient compression of photo-like and diagram-like images in the same format (and in the same image, e.g. screenshots containing photos). * Good lossy compression of diagram-like images.
No.
• There's a draft for gracefully-degrading JPEG eXTensions that add all the features you want http://www.jpeg.org/jpegxt/index.html (by encoding classic JPEG + residual image hidden in JPEG metadata).
WebP is a bit of a hack: it has JPEG-like algorithm for photos (VP8) and a custom PNG-like algorithm for lossless. Technically it's not much different than having JPEG and PNG and using same filename extension for both.
JPEG 2000 and JPEG XR have truly scalable algorithm that can support lossy and lossless.
I did, last summer, converted all images (35K) on my NSFW hobby site (check profile) to WebP with no jpeg fallback or shabby javascript decoder (which don't work on very high res images), and haven't looked back.
On my journey to 1000ms-to-glass with a site like mine, I'm going to go with the format that gives me dramatic size savings, thank you Google.
That said, I can see how it benefits Firefox users not to be able to render WebP... sigh.
It would be helpful if 4chan followed my lead by at least allowing users to post WebP with something like mod_pagespeed running.
I made a sort of Google+ companion to the site which I'd bump them onto but I still haven't gotten the hang of not getting banned.
By the way, it's remarkable when running an image-heavy site how much bot/mass downloader traffic relative to humans vanish when turning away Firefox user agents.
As far as I've seen, testing has shown that WebP is not dramatically better than JPEG, as long as you're using a clever encoder (like MozJPEG, which is what we're talking about). If you have evidence to the contrary, I'm sure the MozJPEG guys would appreciate a test-case!
> That said, I can see how it benefits Firefox users not to be able to render WebP... sigh.
Instead of spending energy on dubious WebP, Mozilla spends energy on improving JPEG (which benefits everybody now) and Daala (which will hopefully benefit everybody eventually). I think it's a pretty sensible trade-off.