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How To Reduce Image Size With WebP Automagically

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Re: How To Reduce Image Size With WebP Automagically

#3
> But with CDN Connect’s automatic image re-encoding, this 52kb PNG shrunk to a 11kb WebP image. That’s a 78% size reduction! Just imagine this image was referenced on every page of your site, and you had handfuls of similar images to download. The potential bandwidth savings and performance improvements are enormous.

What utter garbage. Does CDN Connect want us to believe browsers don't cache images? Sure, that's a savings.. of about 41kb total. Not 41kb per page, just 41kb overall, because my browser's only going to download the image once.

Re: How To Reduce Image Size With WebP Automagically

#4
As much as I like WebP, the numbers given in this article are misleading. The original image is indeed 52 kb. If you like optimizing PNGs, you can recompress it (losslessly, obviously) to ~49 kb. Now the same image in WebP is 35 kb, not 11 kb. The only way for WebP to make it a 11 kb image is to compress it in lossy mode.

Granted, even at 11 kb the image looks really good and there are no visible artifacts but when you put the original image and the lossy version side-by-side, you can see that some tones are slightly off and gradients/shades are slightly different.

Re: How To Reduce Image Size With WebP Automagically

#5
post #3

> But with CDN Connect’s automatic image re-encoding, this 52kb PNG shrunk to a 11kb WebP image. That’s a 78% size reduction! Just imagine this image was referenced on every page of your site, and you had handfuls of similar images to download. The potential bandwidth savings and performance improvements are enormous. What utter garbage. Does CDN Connect want us to believe browsers don't cache images? Sure, that's a…

At the time, 40-60% of Yahoo page views were done with an empty cache: http://www.yuiblog.com/blog/2007/01/04/performance-research-...

Re: How To Reduce Image Size With WebP Automagically

#6
post #4

As much as I like WebP, the numbers given in this article are misleading. The original image is indeed 52 kb. If you like optimizing PNGs, you can recompress it (losslessly, obviously) to ~49 kb. Now the same image in WebP is 35 kb, not 11 kb. The only way for WebP to make it a 11 kb image is to compress it in lossy mode. Granted, even at 11 kb the image looks really good and there are no visible artifacts but when y…

I too like webp, both for lossy and lossless images (particularly lossless), and you're right, the best I got (lossless) was 34.5kb using:

cwebp -lossless -pass 10 -m 6 MaxCDN-WebP.png -o image.webp

Still that's not a bad compression improvement given that 'pngcrush -brute' failed to improve compression and pngout managed only to bring it down to 50.1kb

Re: How To Reduce Image Size With WebP Automagically

#7
post #4

As much as I like WebP, the numbers given in this article are misleading. The original image is indeed 52 kb. If you like optimizing PNGs, you can recompress it (losslessly, obviously) to ~49 kb. Now the same image in WebP is 35 kb, not 11 kb. The only way for WebP to make it a 11 kb image is to compress it in lossy mode. Granted, even at 11 kb the image looks really good and there are no visible artifacts but when y…

Exactly. The 11kb WebP version shows visible degradation: http://f.cl.ly/items/140L0J3d203g410d0m3T/webp-colors.png

The same image can be made into a 13kb PNG (8-bit + imageoptim), without any complex trickery and 99.5% browser support: http://f.cl.ly/items/303H1k2c412s1o0m1b2m/webp-8.png

Re: How To Reduce Image Size With WebP Automagically

#8
post #4

As much as I like WebP, the numbers given in this article are misleading. The original image is indeed 52 kb. If you like optimizing PNGs, you can recompress it (losslessly, obviously) to ~49 kb. Now the same image in WebP is 35 kb, not 11 kb. The only way for WebP to make it a 11 kb image is to compress it in lossy mode. Granted, even at 11 kb the image looks really good and there are no visible artifacts but when y…

Lossy plus alpha isn't cheating, its a legitimate gap in the market. It's also the feature that prompted Mozilla to look at the format again.
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