test0r
4ccbfe923f
Three changes that together make the build compile cleanly against a current linux-api-headers (>= 5.x post-HEVC-UAPI-rename): - src/meson.build: comment h265.c + h265.h out of sources/headers. - include/hevc-ctrls.h: replace bundled HEVC structs with a single #include <linux/v4l2-controls.h>. The bundled definitions were identical to what later landed in mainline as V4L2_CID_STATELESS_HEVC_* (renamed) and v4l2_ctrl_hevc_* (kept the field names but moved into the kernel public header). Keeping a duplicate copy now triggers redefinition errors. The header is kept as a passthrough rather than deleted so any downstream patch that says #include <hevc-ctrls.h> still compiles. - src/picture.c: drop the four HEVC case blocks. Three of them were in switches that already had `default: break`, so removing them is functionally a no-op. The fourth was the only external reference to h265_set_controls — removing it lets the library link cleanly with h265.c excluded. Why this is OK rather than the more ambitious "fix HEVC properly": RK3566 has no HW HEVC at all (the only decoder block is the Hantro G1 which speaks H.264 / MPEG-2 / VP8). HEVC can come back as a separate effort once we're on RK3588 silicon AND the library is updated to the renamed kernel CIDs. For Fourier's first port milestone (H.264 multi- plane on RK3566 hantro) HEVC is dead weight. Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>
v4l2-request libVA Backend
About
This libVA backend is designed to work with the Linux Video4Linux2 Request API that is used by a number of video codecs drivers, including the Video Engine found in most Allwinner SoCs.
Status
The v4l2-request libVA backend currently supports the following formats:
- MPEG2 (Simple and Main profiles)
- H264 (Baseline, Main and High profiles)
- H265 (Main profile)
Instructions
In order to use this libVA backend, the v4l2_request driver has to
be specified through the LIBVA_DRIVER_NAME environment variable, as
such:
export LIBVA_DRIVER_NAME=v4l2_request
A media player that supports VAAPI (such as VLC) can then be used to decode a video in a supported format:
vlc path/to/video.mpg
Sample media files can be obtained from:
http://samplemedia.linaro.org/MPEG2/
http://samplemedia.linaro.org/MPEG4/SVT/
Technical Notes
Surface
A Surface is an internal data structure never handled by the VA's user containing the output of a rendering. Usualy, a bunch of surfaces are created at the begining of decoding and they are then used alternatively. When created, a surface is assigned a corresponding v4l capture buffer and it is kept until the end of decoding. Syncing a surface waits for the v4l buffer to be available and then dequeue it.
Note: since a Surface is kept private from the VA's user, it can ask to directly render a Surface on screen in an X Drawable. Some kind of implementation is available in PutSurface but this is only for development purpose.
Context
A Context is a global data structure used for rendering a video of a certain format. When a context is created, input buffers are created and v4l's output (which is the compressed data input queue, since capture is the real output) format is set.
Picture
A Picture is an encoded input frame made of several buffers. A single input can contain slice data, headers and IQ matrix. Each Picture is assigned a request ID when created and each corresponding buffer might be turned into a v4l buffers or extended control when rendered. Finally they are submitted to kernel space when reaching EndPicture.
The real rendering is done in EndPicture instead of RenderPicture because the v4l2 driver expects to have the full corresponding extended control when a buffer is queued and we don't know in which order the different RenderPicture will be called.
Image
An Image is a standard data structure containing rendered frames in a usable pixel format. Here we only use NV12 buffers which are converted from sunxi's proprietary tiled pixel format with tiled_yuv when deriving an Image from a Surface.