The latest notch in Bootlin's belt for improving the Linux multimedia landscape is crafting H.264 encode support for the Allwinner V3/V3s/S3 hardware. This complements their prior work for accelerated video decode.
This encode support is currently staged in Bootlin's GitHub repository. Unfortunately it's not yet ready for upstreaming due to there not yet being a well-defined user-space API for exposing stateless decoders. That work around new uAPIs is an ongoing discussion.
In any event those with Allwinner V3, V3s, and/or S3 SoCs can find out more about this new open-source H.264 video encode support via this blog post by Bootlin's Paul Kocialkowski.