Googles new Webp image format

Ritho · 01. Oct 2010, 02:28 PM

Google has just released a preview of their new image format called webp. They hope it will replace jpeg and speed up image loading on websites since it gets much better compression rates with certain types of images that jpeg when compared at the same quality.

You can see some of the results here.

http://code.google.com/speed/webp/gallery.html

Anupam · 01. Oct 2010, 03:54 PM

Google always keeps coming up with something or the other. They never stop.

The WebP images are really PNG, or WebP contained inside PNG? I didnt get it exactly... but the jpg images loaded quickly, and WebP were taking too much time to load, whereas they were supposed to load quickly because of smaller size.

Jojoyee · 01. Oct 2010, 04:12 PM

That's good news. Can't see the difference even the image size is reduced by 66% after converting jpg to webp, as shown in the gallery.

Jojoyee · 01. Oct 2010, 04:24 PM

Quote:

Originally Posted by Anupam

The WebP images are really PNG, or WebP contained inside PNG? I didnt get it exactly... but the jpg images loaded quickly, and WebP were taking too much time to load, whereas they were supposed to load quickly because of smaller size.

The ones shown in the gallery are jpg on the left and png on the right. There're no webp images in that page per se as no browser can show them now. In actual fact, the png images are larger than the jpg files in sizes physically shown in that page, that explains their slower display.

The numbers beneath the images are the file sizes of the original pictures in jpg and webp formats, which are not displayed in your browser yet.

Anupam · 01. Oct 2010, 04:30 PM

Ah! Thanks for that explanation Jojo

.

Doobie · 04. Oct 2010, 02:54 AM

The Webp samples Google demonstrates are about 9ish:1 compression, too low to be very useful in a comparison. Even a bad encoder looks good as such a mild compression ratio.

By starting with 7ish:1 compressed jpegs, they're cheating. Jpeg has already reduced the picture quality by eliminating the hard-to-encode bits and the less important visual information. This loss of detail is not shown because Google doesn't show the uncompressed images. The jpeg has been made the reference. All Webp has to do is improve on this by less than 2:1. My cat could write a compression format that can compress without obvious loss of detail at 2:1. (Assuming you're not as smart as my cat, I've simplified this explanation, so it lacks a bit of technical accuracy.)

It also doesn't help the viewer when Google displays reduced-dimension images which helps hide compression artifacts. (Do I have to spell it out? Smaller details disappear before bigger details.)

Unless Google makes progress in tweaking it and ditches the PSNR opt.(another way Google cheats, by starting with jpegs, Webp's PSNR opt. is defeated), Webp is not even as good as ca. 1990 jpeg.

George · 04. Oct 2010, 06:47 AM

Quote:

Originally Posted by Jojoyee

There're no webp images in that page per se as no browser can show them now.

Maybe that's the whole trick. The browser can't display them, thus, they don't download them, thus, you save all the bandwidth! :-)

Doobie · 04. Oct 2010, 10:38 PM

Quote:

Originally Posted by George

Maybe that's the whole trick. The browser can't display them, thus, they don't download them, thus, you save all the bandwidth! :-)

How do you save bandwidth downloading the larger PNG variants?

01. Oct 2010, 02:28 PM	#1 (permalink)
Ritho Foundation Editor Join Date: Apr 2008 Location: Planet Earth Posts: 1,391	Googles new Webp image format Google has just released a preview of their new image format called webp. They hope it will replace jpeg and speed up image loading on websites since it gets much better compression rates with certain types of images that jpeg when compared at the same quality. You can see some of the results here. http://code.google.com/speed/webp/gallery.html __________________ The smallest good deed is better than the greatest intention.

01. Oct 2010, 03:54 PM	#2 (permalink)
Anupam Moderator Join Date: Jul 2008 Location: India Posts: 9,484	Google always keeps coming up with something or the other. They never stop. The WebP images are really PNG, or WebP contained inside PNG? I didnt get it exactly... but the jpg images loaded quickly, and WebP were taking too much time to load, whereas they were supposed to load quickly because of smaller size. __________________ Anupam

01. Oct 2010, 04:12 PM	#3 (permalink)
Jojoyee Maestro di Search Join Date: Jul 2008 Posts: 4,295	That's good news. Can't see the difference even the image size is reduced by 66% after converting jpg to webp, as shown in the gallery. __________________ Keep It Short and Sweet

01. Oct 2010, 04:30 PM	#5 (permalink)
Anupam Moderator Join Date: Jul 2008 Location: India Posts: 9,484	Ah! Thanks for that explanation Jojo . __________________ Anupam

Thread Tools
Show Printable Version Email this Page
Display Modes
Linear Mode Switch to Hybrid Mode Switch to Threaded Mode

04. Oct 2010, 02:54 AM	#6 (permalink)
Doobie Full Member Join Date: May 2010 Posts: 39	The Webp samples Google demonstrates are about 9ish:1 compression, too low to be very useful in a comparison. Even a bad encoder looks good as such a mild compression ratio. By starting with 7ish:1 compressed jpegs, they're cheating. Jpeg has already reduced the picture quality by eliminating the hard-to-encode bits and the less important visual information. This loss of detail is not shown because Google doesn't show the uncompressed images. The jpeg has been made the reference. All Webp has to do is improve on this by less than 2:1. My cat could write a compression format that can compress without obvious loss of detail at 2:1. (Assuming you're not as smart as my cat, I've simplified this explanation, so it lacks a bit of technical accuracy.) It also doesn't help the viewer when Google displays reduced-dimension images which helps hide compression artifacts. (Do I have to spell it out? Smaller details disappear before bigger details.) Unless Google makes progress in tweaking it and ditches the PSNR opt.(another way Google cheats, by starting with jpegs, Webp's PSNR opt. is defeated), Webp is not even as good as ca. 1990 jpeg.