This release adds full support for reading and writing HEIF image sequences.
libheif will now encode HEIF image sequences with all included codecs.
Since HEIF image sequences are very similar to MP4 videos, this new version is also capable of decoding most MP4 videos (without audio, of course).
heif-enc documentation for sequence encoding
API documentation for reading and writing sequences
Other major changes:
- Support for image sequences with alpha channels. For most codecs, the alpha channel will be stored in a separate, auxiliary, monochrome track. For ISO/IEC 23001-17 (uncompressed) streams, the alpha channel is stored in the main video track.
- Support for sequence track edit lists to define the number of sequence repetitions (without actually repeating the video data).
- New encoder plugin using x264 to write H.264-compressed video streams and images.
- The FFmpeg decoder plugin will now decode both H.265 and H.264.
- Support for HEIF text items and language properties (thanks to @bradh).
CVEs fixed:
- CVE-2025-68431