Linux's Stateless H.264 Decode Interface Ready To Be Deemed Stable

The Linux kernel's stateless video decoder interface is used for video decoding where no state needs to be kept between processed video frames and allows for independently decoding each video frame. The H.264 stateless decode interface for the Linux kernel has been in the works for a few years and is now deemed ready and stable for dealing with modern stateless codecs.

Ezequiel Garcia of Collabora sent out a patch series for de-staging the stateless H.264 support and to move it into the formal kernel area. With that the user-space API around the H.264 stateless decoding is deemed "solid" and stable. Porting of the GStreamer V4L2 codecs to the new interface is now underway and FFmpeg/libavcodec is also looking to make use of this stateless interface.

Mainline Linux video decoders supporting this H.264 stateless video decode right now are the Allwinner Cedrus and Rockchip RKVDEC drivers.

If all goes well, this promotion of H.264 stateless support could happen for Linux 5.11.