Last week, Google announced they have developed a new image format called WebP (pronounced “weppy”), an initiative aimed at speeding up the web — specifically, images. Google’s angle is that most of the image formats used on the web today were established many years ago, and as such, use technology developed at that time that could now be considered outdated. As a result of the outdated image formats, a website user’s experience is degraded because of bandwidth constraints and loading large images.
JPEG, one of the leading image formats used on the web today, is an already compressed format of an original image, the compression of which can be adjusted on a per picture basis to create the perfect intersection of image size and image quality. Generally, JPEG’s are compressed to around 10:1 with typically little noticeable loss of image quality. Google hopes to improve JPEG compression with an image compressor based on a codec they developed in May 2010. Google hopes to achieve this improvement with predictive coding:
WebP uses predictive coding to encode an image. Predictive coding uses the values in neighboring blocks of pixels to predict the values in a block, and then encodes only the difference (residual) between the actual values and the prediction. The residuals typically contain many zero values, which can be compressed much more effectively.
Photo editing software developers are beginning to add support for WebP, an indication that the new format is being well received by the software development community and support will be widely available in major photo editing software packages.
The question to ask, though, is will website developers make the switch? In particular, will website developers of existing sites go back and re-optimize all of their images in the new WebP format? The success of the WebP format will certainly depend on the developer’s adaptation of the new format and willingness to change from the long-standing JPEG and GIF formats. If WebP delivers on reducing image sizes by up to 40% as it claims and becomes fully adopted throughout the software image editor industry, the decision would ultimately come down to staying with what a developer knows and has used in the past or increasing website speed by adopting the new format.
What is more important to you — a tried and true format or a new product that could potentially increase your site load time?