Writes in his tech blog the Netflix development team: "We need an alternative to JPEG." However, this must have broad support, compress more efficiently than JPEG and also offer a greater range of functions than this. The Netflix developers write that these criteria are all met by the AV1 image format AVIF. The team will implement some experiments with it in the future.
AVIF is a format for single images instead of videos, but it supports and uses the same encoding techniques as the free video format AV1 from the Alliance for Open Media (Aomedia). In addition to the video streams themselves, frames are of particular importance for Netflix. After all, the service interface shows the catalog of offers with a large number of preview or title images for the corresponding content.
As the team writes, these images consist of a variety of different components such as the actual image for the streaming content, but also the text, color gradients or other graphics. This leads to some peculiarities that in "natural pictures" does not occur, it is said. In addition, Netflix very often uses facial representations in these covers. All of this requires certain precautions when encoding the images.
Netflix has in addition to the basic considerations published a frameworkwith which the quality of different encoders for identical output images should be compared. The provider presents the results of its own investigations in an exemplary manner on its blog. Especially in direct comparison to JPEG, AVIF performs significantly better. Not surprisingly, after all, there are almost 25 years of development between the two formats. The significantly better encoding quality of AVIF compared to JPEG with approximately the same size of the files is nevertheless impressive.
Despite the significantly better quality, AVIF is not yet widespread, it says in the blog entry. The integration of AVIF decoders in browsers, for example, has already begun. Thanks to the integration of Dav1d in its own offering, Netflix can also use AVIF in its Android app in the future. The streaming provider will probably also test this soon. The team is also working on HDR images for its surfaces and plan to use AVIF for this as well.