Google is constantly trying to bring new technological improvements and to provide a friendlier experience to their users. Their latest contribution is an algorithm which encodes a 35 percent smaller JPEG image in file size. They introduced this technique under the name of Guetzli.
Google aimed to reduce the size of already existing JPEG images so that web pages could load faster. After performing a research on the image requests on the internet, they discovered that more than half of these are JPEGs. After seeing the popularity of this image format, they decided that they should experiment with it, instead of creating a new one.
Shrinking images at no cost
Thus, they started experimenting with this format and reached the conclusion that reducing their size would bring a better browsing experience. This compression technique they implemented is a great improvement over the current methods used when compressing JPEGs.
The Guetzli algorithm (which means “cookie” in Swiss German) is pretty similar to Zopfli, which is the technique used to shrink PNG or .gzip files without having to resort to a new format. They are different from the RNN algorithms of image compression. These require some changes to be made, as opposed to these new techniques.
What technology do they use?
Google said that the quality of the image is strongly related to the compression process. Guetzli reduces the size of the images by analyzing the possible loss in quality. Before the shrinking process, the algorithm analyzes color perception and visual masking. Thus, it succeeds in reducing the size of the image file with minimal quality loss.
The research engineers Robert Obryk and Jyrki Alakuijala explained the process in more details in an official blog post.
“Guetzli specifically targets the quantization stage in which the more visual quality loss is introduced, the smaller the resulting file. Guetzli strikes a balance between minimal loss and file size by employing a search algorithm that tries to overcome the difference between the psychovisual modeling of JPEG’s format, and Guetzli’s psychovisual model.”
The only downside is the fact that Guetzli takes quite a long time to compress the images. There are other algorithms, such as libjpeg, which can convert the files more quickly. However, people preferred the images produced by Guetzli rather than those produced by libjpeg.
Google came up with an innovative idea which can significantly reduce the loading time of web pages, thus improving the users’ browsing experience.
Image Source: Pixabay