This field may be set by the caller before calling av_hwframe_ctx_init().
If non-NULL, this callback will be called when the last reference to this context is unreferenced, immediately before it is freed.
See Implementation
This field may be set by the caller before calling av_hwframe_ctx_init().
If non-NULL, this callback will be called when the last reference to this context is unreferenced, immediately before it is freed.