Overview: Linux
Linux media interfaces connect codec operations, driver backends and picture-sharing mechanisms.
A VA-API path depends on its backend, and V4L2 codec arrangements have their own stateful or stateless relationships. VDPAU supplies another video interface; DRM PRIME and DMA-BUF concern picture sharing across components. This group keeps those layers visible when diagnosing a working decoder with a difficult downstream handoff.
Video Acceleration API (VA-API)
VA-API exposes video decode, encode and processing operations through profile/entrypoint configurations implemented by a selected device driver backend.VA-API driver backends
A VA-API backend implements the interface for a supported device and driver stack, so loader selection, hardware identity and backend capabilities determine the usable media path.Video Decode and Presentation API for Unix (VDPAU)
VDPAU provides Unix video decoding, mixing and presentation interfaces with defined surface types and driver-backed capability relationships.V4L2 memory-to-memory codecs
A V4L2 memory-to-memory codec transforms application-supplied buffers through paired source and destination queues whose formats, ownership and state define the media operation.V4L2 stateless decoding and the Request API
V4L2 stateless decoding makes the application supply per-picture decoding state, references and encoded data through requests that bind the operation’s controls and buffers.DRM PRIME and DMA-BUF frame sharing
DRM PRIME and DMA-BUF let compatible Linux subsystems exchange references to frame storage while layout, synchronization and ownership determine how the shared picture may be used.