October 1, 2010 at 03:53WebP, a new image format for the Internet
- Transfer
As part of Google’s initiative to make the Internet faster, over the past months we have released a whole range of tools designed to help website owners speed them up. We launched an extension for Firefox called Page Speed , which allows you to study the performance of web pages, as well as receive suggestions on how to increase it. We introduced Speed Tracer , an extension for Chrome that allows you to find and fix performance issues in web applications. In addition, we released a set of tools for the final stage of development ( closure tools), designed to help create complex web applications with fully optimized javascript code. While these tools were incredibly successful in helping developers optimize their sites, we continued to work, and we were able to discover the only component of web pages that is fully responsible for the majority of page delays: images.
Most of the common image formats used on the network were created over 10 years ago and are based on the technologies of that time. Google engineers decided to check: is there no way to increase the compression ratio of lossy compression algorithms (like JPEG) to allow images to load faster, while fully preserving their resolution and visual quality. As a result of working on this project, we are releasing a new image format,WebP , in the preliminary version for developers. This format promises to significantly reduce the binary size of photos on the network, allowing sites to load faster than before.
Today, images and photographs make up about 65% of all data making up a web page. They can significantly slow down your network, especially in networks with limited traffic, such as mobile networks. Most of the images on the network are lossy compression formats (such as JPEG ), while the smaller are lossless compression formats (such as GIF and PNG ). Our team has concentrated on improving lossy compression, since today it is the images in such formats that make up the majority of all images on the network.
To improve the compression ratio, which is offered by the JPEG format, we used an algorithm based on the codec used in the VP8 , which sources have been discovered by Google in May 2010. We used the technologies used in VP8 to compress intermediate frames, to compress static images. In addition, we used a very compact format of the container file based on the RIFF format : despite the fact that this format adds only 20 bytes to each image, it is extensible, which allows authors to save any necessary metadata in a file.
Although the advantages of the VP8-based image format are theoretically obvious, they had to be tested in real-world conditions. To evaluate the effectiveness of our efforts, we selected about a million random images from the network (mainly JPEG, as well as some PNG and GIF) and transcoded them into WebP, preserving their visual quality. Such transcoding led to a reduction in file size by 39% ( apparently, mean, on average. Approx. Translations ). We expect developers to achieve even greater compression with the WebP format by compressing images that were not originally compressed.
To help you evaluate the effectiveness of WebP compared to other formats, we have prepared a set of well-known free images in different formats, indicating also the size of the images so that you canCompare them visually . In addition, we are releasing a converter program that you can use to convert images to WebP format. We look forward to working together with both browser manufacturers and the community of web developers, on the WebP specification and on adding support for this format to browsers. Although WebP images cannot be displayed until browsers support this format, we are working on a patch for Webkit that will provide WebP support in the next version of Google Chrome. In addition, we plan to add support for the transparency layer , also known as the alpha channel, in the form of an update in the future ( Chrome updates or format specifications? It’s not clear. Note perev ).
We are really looking forward to feedback from the development community in our group , so download the converter , try it on your favorite set of images, and let us know what you think.
Richard Rabbat, Product Manager.
Most of the common image formats used on the network were created over 10 years ago and are based on the technologies of that time. Google engineers decided to check: is there no way to increase the compression ratio of lossy compression algorithms (like JPEG) to allow images to load faster, while fully preserving their resolution and visual quality. As a result of working on this project, we are releasing a new image format,WebP , in the preliminary version for developers. This format promises to significantly reduce the binary size of photos on the network, allowing sites to load faster than before.
Today, images and photographs make up about 65% of all data making up a web page. They can significantly slow down your network, especially in networks with limited traffic, such as mobile networks. Most of the images on the network are lossy compression formats (such as JPEG ), while the smaller are lossless compression formats (such as GIF and PNG ). Our team has concentrated on improving lossy compression, since today it is the images in such formats that make up the majority of all images on the network.
To improve the compression ratio, which is offered by the JPEG format, we used an algorithm based on the codec used in the VP8 , which sources have been discovered by Google in May 2010. We used the technologies used in VP8 to compress intermediate frames, to compress static images. In addition, we used a very compact format of the container file based on the RIFF format : despite the fact that this format adds only 20 bytes to each image, it is extensible, which allows authors to save any necessary metadata in a file.
Although the advantages of the VP8-based image format are theoretically obvious, they had to be tested in real-world conditions. To evaluate the effectiveness of our efforts, we selected about a million random images from the network (mainly JPEG, as well as some PNG and GIF) and transcoded them into WebP, preserving their visual quality. Such transcoding led to a reduction in file size by 39% ( apparently, mean, on average. Approx. Translations ). We expect developers to achieve even greater compression with the WebP format by compressing images that were not originally compressed.
To help you evaluate the effectiveness of WebP compared to other formats, we have prepared a set of well-known free images in different formats, indicating also the size of the images so that you canCompare them visually . In addition, we are releasing a converter program that you can use to convert images to WebP format. We look forward to working together with both browser manufacturers and the community of web developers, on the WebP specification and on adding support for this format to browsers. Although WebP images cannot be displayed until browsers support this format, we are working on a patch for Webkit that will provide WebP support in the next version of Google Chrome. In addition, we plan to add support for the transparency layer , also known as the alpha channel, in the form of an update in the future ( Chrome updates or format specifications? It’s not clear. Note perev ).
We are really looking forward to feedback from the development community in our group , so download the converter , try it on your favorite set of images, and let us know what you think.
Richard Rabbat, Product Manager.