Google’s JPEG Alternative WebP Gets Smarter, Takes on PNG

Last year, Google introduced a new image format for the web called WebP. WebP is meant to be a modern alternative to the popular but patent-encumbered JPEG standard. It produces significantly smaller files without sacrificing image quality. Today, Google announced some new features for WebP that may help bring wider adoption to the format, which is currently only natively supported by Opera and Google’s own Chrome browser. With today’s updates, WebP now offers a lossless mode as as well as support for transparency. Both of these features are currently the domain of the lossless PNG format which is currently the JPEG alternative of choice for designers who need either transparency or lossless encoding on their sites.


According to Google’s test, the new lossless mode “offers a 45% reduction in size when starting with PNGs found on the web, and a 28% reduction in size compared to PNGs that are re-compressed with pngcrush and pngout” (both of which are popular tools for optimizing PNG files).

Similarly, the new transparency mode should offer designers the option to reduce the size of those images that need this feature over today’s PNG files. Overall, these WebP images show a significant reduction in file size.

In addition to all of these features, it’s also worth noting that Google added “support for animation, ICC profile, XMP metadata and tiling” to WebP about a month ago.

Good Format, But it’s Fighting an Uphill Battle

For Google, this project is all about making websites smaller and hence faster to load. After all, when pages load faster, you are more likely to see the ads on those pages. As with all new formats, though, Google is  fighting an uphill battle here. Unless other browser manufacturers support it (and unless there are enough products out there that can produce WebP images), this mostly remains an interesting computer science effort but won’t see wide adoption.

It’s worth noting, though, that you may already be seeing more WebP images, as Google’s own mod_pagespeed module for Apache can already convert JPEG images to WebP on the fly for browsers that support it.