Thank you for your answer, I have solved this problem, but I have encountered a new problem, I want to use V4L2 to develop the SC3336 camera, according to the prompt I use /dev/video15, but the program prompt has been unable to find the device.
I have used this command：
v4l2-ctl --device=/dev ...

I added ffmpeg to buildroot and ran into this problem when compiling.

{SDK}/sysdrv/tools/board/gdb/gdb-10.2/missing: 81: makeinfo: not found
WARNING: 'makeinfo' is missing on your system.
You should only need it if you modified a '.texi' file, or
any other file indirectly affecting the aspect of ...