File Formats: AV1 File Format (AVIF)

The AV1 File Format (AVIF) stores images compressed with the AV1 compression in a HEIF container. The AVIF format supports single-image and sequences, but at the moment LEADTOOLS supports reading and writing single-image AVIF files.

The HEIF container is also used for storing HEIC images. The AVIF format was designed to be royalty free, whereas the HEIC format uses HEVC compression, which is covered by several patents.

The file constants associated with AVIF are:

LEADTOOLS supports the following AVIF features:

• Thumbnails (Stamps). Use ReadStamp to read a thumbnail. You can save a thumbnail by setting the SaveWithStamp property to true prior to calling the save function.

• Metadata. Store and read comments and tags supported by TIFF and EXIF. For additional EXIF file format information, refer to Exif File Comments and Exif File Extensions.

• 8-bit, 10-bit and 12-bit components. Most AVIF files have 8-bit components, but some have 10 and 12-bit components. The files can have one component or 3 components. 1-component files are grayscale, while 3-component files are color. The files can also have an optional extra image containing alpha channel information. Each component can be 8, 10 or 12-bit. LEADTOOLS will load images with 10-bit and 12-bit components but will currently Save only 8-bit components. Images with 8-bit components will be loaded by default as 8-bit (grayscale), 24-bit (color) or 32-bit (color + alpha). Images with 10 or 12-bits per pixel components will be loaded by default as 16-bit (grayscale), 48-bit (color) or 64-bit (color + alpha).

• Alpha channel/transparency information. If the AVIF file has an Alpha plane, LEADTOOLS will automatically load it. AVIF files with 8-bit components plus an Alpha plane use 32-bits per pixel of memory when loaded. AVIF files with 10/12-bit components plus an Alpha plane use 64-bits per pixel of memory when loaded. For each pixel, the corresponding alpha value provides full translucidity, semi-translucency or full opacity control as described in the table below:

  Alpha Value	Description
  0	Fully transparent
  1-254	Semi-translucent
  255	Fully opaque

• Rotate, flip, and reverse transformations. Perform a lossless rotate, flip, or reverse transformation of an existing file using the Transform method.

Required DLL

Leadtools.Codecs.Heif.Dll. For a listing of the exact DLLs needed, based on the toolkit version, refer to Files To Be Included With Your Application.

Related Formats

• HEIC - High Efficiency File Format.

• EXIF - Exif Formats.