Google wants to shrink images transferred over the Internet by proposing a new lossy format called WebP. They claim they have achieved 39% reduction in image byte size leading to speedier page load.
WebP (pronounced "weppy" /(wĕpˈē)/) is an image lossy compression format developed by Google and meant to shrink the size of image files. Google claims that images and photos represent around 65% of the total bytes sent over the Internet these days, which is quite a significant share of all traffic. It is understandable that lowering the number of bytes per picture will have an impact on the average page size, speeding up page loads.
WebP uses a compression algorithm borrowed from the VP8 codec used by Google in WebM, the open source media file format for encoding and compressing video. The overall effect of using WebP is an average of 39% reduction in image byte size after converting 1,000,000 randomly chosen pictures, mostly JPEGs and some PNG and GIFs. Google affirms the image quality has not significantly degraded after the conversion.
WebP is meant to replace JPEG as a better lossy compression format. WebP images are delivered into a lightweight RIFF container, adding a small number of bytes per picture (minimum 20 bytes) but having the ability to contain more in case the picture should be accompanied by more meta-data.
Currently Google is providing a free open source decoder and a conversion tool for Linux x86 64-bit. A Windows version is due in the near future. Google is also working on a WebKit patch enabling Chrome to display WebP images.
An image gallery has been set up to allow anyone to compare the quality of WebP images against their JPEG originals. WebP images have been encapsulated into a PNG container so they can be seen with actual browsers.
Google plans to add support for a transparency layer in the future. WebP belongs to Google’s initiative "Let's make the web faster" including projects like Page Speed, Speed Tracer, and SPDY.
