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Google Releases New Image Format Called WebP
An anonymous reader writes "Google has released WebP, a lossy image format based on the image encoding used by VP8 (the video codec used in Google's WebM video format) to compress keyframes. According to the FAQ, WebP achieves an average 39% more compression than JPEG and JPEG 2000 while maintaining image quality. A gallery on the WebP homepage has a selection of images which compare the original JPEG image with the WebP encoded image shown as a PNG. There's no information available yet on which browsers will support the WebP image format, but I imagine it will be all the browsers which currently have native WebM support — Firefox, Chrome, and Opera."
Independent analysis of WebP is available from a few different sources.
I can visibly see a difference in ALL the pictures. The WebP version is slightly murkier and less shows less detail than the JPEG version.
It's like people say you can't hear the difference in suitably high-bit rate MP3, but I can - in the cymbals - they're not as bright as CD or FLAC.
This is kind of like that. It's ALMOST pretty great, but it's not as great. I guess if we all lower our expectations, we can get used to it.
Meh. I always use PNG anyway. With the advent of faster web connections, there is no need for more compression.
Is WebP free?
Does Google have any patent claims or other intellectual property claims (pending or otherwise) over WebP/
If so, then it is not free :-(
This makes no sense to me. The /. summary claims the webp images are built from the jpeg images. The jpeg images have already suffered loss and thus sacrificed image quality, and if correct any further processing will only be worse, never better. The proper test would be to make a comparison between two forms of lossy compression based on a lossless source (such as a raw file), which I suspect may be what really happened in the comparison. Of course, some people will take poor quality jpeg images and try to compress them further, but you can't blame the bad results this will produce on the new format technology.
I'm an American. I love this country and the freedoms that we used to have.
Read the damn WebP sites own description:
"Webmasters, web developers and browser developers can use the WebP format to create smaller, better looking images that can help make the web faster."
So, no the OP running his mouth off doesn't have a clue. Nor do you.
Storage space is cheap.
Computation is cheap.
Bandwidth is not.
"Are you offering to recode all of these sites to support both WebP and non-WebP browsers?"
Why would anyone give a damn if a site is dumb enough to pass large savings in bandwidth for serving the exact same content?
Colors seem a little strange..
I noticed there was some color variance in the example, so I actually looked at the VP8 spec and it is in YUV color space.
Which makes sense, VP8 was made for video.
However it appears there is a RGB to YUV color space conversion in the examples shown.
My graphic designer is going to cut my nuts off if I convert her images to WebP using webpconv.
To do this correctly I guess you should also source your raw material in YUV for color accuracy.
Believe me, purple is just not purple as i have been told. :-P
She is cute though, so I dont argue with her.
Problem is that, according to the analysis by the x264 developer (see the first independent analysis link), WebP is missing quite a few features that JPEG has, does not add any of the features JPEG is missing but people really want (like a lossy format that contains alpha capability - although admittedly, lossy compression of the alpha channel itself could cause some REALLY weird artifacts.)
It also, at least in the current state of the encoder, does not appear to perform any better than JPEG.
retrorocket.o not found, launch anyway?
If you already know which is WebP and which is JPG, you're unavoidably biased. We're not going to settle this without a blind trial.
Slashdot hackers! Your mission, should you decide to accept it, is to write a little website which encodes a series of raw never-been-compressed images as WebP and JPG of equal sizes, presents both side-by-side to the user, and has them click on the one they think is "better". Do not label which image is which: randomize them. Collect statistics and present the data on the site.
Any good php hacker should be able to whip this up in about an hour. I'd do it, but I've got work to do.
The JPEG standard is not perfect. There's several more efficient and effective image codecs available now that were impractical in 1992. However it's relative simplicity and age mean it is trivial to handle on contemporary machines and is available everywhere. Just about any graphical web browser you can find supports JPEG images. While WebP might offer best case space savings over JPEGs of equivalent size the idea that it's somehow appropriate for mass consumption is absurd. The justification of JPEGs slowing down load times for web pages is ludicrous, JavaScript doing a half-assed job of loading resources and unoptimized server access causes far more problems than additional kilobyte in an image. It's yet another half-baked Google project released because there's not enough parental supervision going on.
WebP does not offer any compelling reason except a promise of space/bandwidth savings over JPEG. It doesn't currently support multiple color spaces, color correction, an alpha channel, or animation. It's promise of space savings at various quality levels is ridiculous because like they did with VP8/WebM Google is only focusing on PSNR measurements. PSNR makes for nice graphs but is not an effective measurement of how images actually look to people. An image that scores well in a PSNR test might look like shit when you actually compare it to the source image. Most JPEG encoders are tuned for psychovisual performance, not to score well in PSNR tests. Testing WebP vs JPEG with VQM tests would be far more appropriate but I suspect WebM would do far worse than with PSNR (since that's what VP8 is tuned for).
Without a VQM test it's really not appropriate to say that at a given size WebP has better visual quality than JPEG. Even if this turned out to be the case it's missing a lot of other important features that JPEG either has or a truly viable replacement for JPEG should have. WebP only supports a single color space and color profile so if your source images look like shit in that space or with that profile you're out of luck. JPEG can declare an image's color profile or provide its own ICC. It doesn't support lossless encoding or an alpha channel (right now) so it won't be appropriate to replace PNGs and GIFs which are often less optimized for the web than JPEG. It also doesn't support animation which for good or ill is still an important use of GIF files.
Yet another image format to not get widely accepted on the web doesn't do anyone any good. Why not help support JPEG-2000 or JPEG-XR? Help PNG out with a F/OSS compatible LZMA library. No camera manufacturers will support it because they can't just write a few Exif tags and attach an ICC profile and have a usable image. Converting your personal library means you get not only a lossy-to-lossy conversion but lose the ability to do lossless editing (rotation etc). Because WebP has more complicated encoding than JPEG it's going to require more CPU power to decode, your iPhone an Droid will get worse battery life browsing WebP content than JPEG content. The reduced file size (assuming WebP lives up to its promises) isn't going to make up for the vastly more complicated decoding. So hooray, Google managed to reuse their VP8 encoder for still images while simultaneously not solving any actual problems with images on the web.
I'm a loner Dottie, a Rebel.