Google comes with jpeg compression that should make photos up to a third smaller

Google has proposed a new way of compression on jpeg files that should make images on the web up to a third smaller without visible loss of quality. Due to the smaller files, websites have to load faster.

Google calls the new compression Guetzli, and researchers at the company proposed the technique in a paper on Arxiv. File size can be reduced using Google’s proprietary .butteraugli technique, which compares the ‘psychic visibility’ of differences between images.

Using that technique, Guetzli can strip information from the image that .butteraugli expects people not to see. As a result, in addition to the smaller file size, Guetzli’s jpegs should look better than current jpegs, which are compressed with libjpeg, for example.

This isn’t the first time the search company has attempted to reduce the size of images on the web. A few years ago, it introduced a new file format, webp, which Google itself uses for, for example, screenshots in the Play Store and thumbnails on YouTube. Google has a great interest in smaller images because it stores a lot of images on its servers.

Left: the uncompressed image. Middle: Compressed with different jpeg compression. Right: jpeg of Guetzli