The GNU Image Manipulation Program (GIMP) is a free and open-source raster graphics editor. While it was developed as a Linux Image editor, it has evolved into an effective alternative for Photoshop from Adobe, while remaining both free and open source.
AVIF Support for new images
As GIMP 3.0 development has been going on, on the 7th of October 2020, GIMP 2.10.22 was released. This release is titled a bug fix, however it had severe effects on GIMP's functionality. Since then, thanks to the encoder libheif, it is now capable of supporting the AVIF image format natively, which means that you can import and export AV1-based AVIF images as you would any other supported format.When exporting an image from the editor, choose the "HEIF/AVIF" file type or use the ".avif" extension. A prompt will then appear, in which you will have the chance to select among several possible options. First, you will have the chance to choose the degree to which you wish to preserve the image's quality. We recommend a value above 20 and will give you a more detailed comparison below this text. Furthermore, you can adjust the image's bit depth. You can choose between 8, 10 or 12 bits per channel. The higher the bit depth, the greater the amount of colors that will be saved to your image. For comparison, JPG has 8 bits. So if you're not a photographer and just want to use AVIF images for your website, we recommend that you stick with 8-bit.
. Despite the non-creative name, the user interface is fantastic. It allows for many options to choose from, such as the minimum and maximum Quantizer, pixel format, bit depth, encoder, encoder speed, alpha channel settings, EXIF data and XMP data handling, and the ICC color profile. If you do not understand most of these settings, don't worry; you will probably be fine with the default interface.
AVIF Support for existing images
If you look to have a lot of images converted, it's a lot easier to convert them all in one go. Make life easier for yourself by