libv4l-rkmpp

A V4L2 plugin that wraps rockchip-mpp for the chromium's V4L2 VDA/VEA (requires custom patches to enable those features).

The original idea comes from v4l-gst.

Dependencies

   $ meson build
   $ meson compile -C build

   # echo dec > /dev/video-dec0
   # chmod 666 /dev/video-dec0
   # echo enc > /dev/video-enc0
   # chmod 666 /dev/video-enc0

Run chromium's VDA/VEA

The VDA's thumbnail tests would fail, which is harmless since we are not in the md5 checksum list

The VEA's CacheLineUnalignedInputTest test might crash, which is due to VEA buffer managing issue.
Run with chromium browser:

   export XDG_RUNTIME_DIR=/run/user/0
   chromium --no-sandbox --gpu-sandbox-start-early --ignore-gpu-blacklist

This plugin is tested with custom chromium on rk3399

There're a lot of chromium related hacks in it, might not work for other apps.

For proper decoding usage, there's a ffmpeg solution with a few extra buffer copies.

MPP reports errors?

Try the newest MPP release branch or develop branch or the commit with the closest commit date.

Also test with the mpi_dec_test to check if the MPP works:

# mpi_dec_test -t 7 -i test-25fps.h264

The plugin complaining about "ERR: failed to init rga"?

Make sure "/dev/rga" exists and accessable by the chromium.
How to get more verbose logs?

For chromium, use these command line flags to change the log level: --enable-logging --vmodule=/media/gpu=4

For libv4l-rkmpp, set the "LIBV4L_RKMPP_LOG_LEVEL" environment variable to change the log level. And set "LIBV4L_RKMPP_LOG_FPS" to enable logging fps.

For MPP, set the environment variable "mpp_debug", "rkv_h264d_debug", "mpp_dec_debug", "mpi_debug", etc. to change the modules' log levels.

For vpu driver, write verbose log level to "/sys/module/rk_vcodec/parameters/debug".
What about the performance?

The performance should be much the same as other MPP based decoders/encoders (e.g. mpi_dec_test and gstreamer MPP plugin).

And the performance would mostly related to the video's attributes (e.g. resolution and bitrate) and the vpu clock rates.