Add a new side data to a frame from an existing AVBufferRef
@param frame a frame to which the side data should be added
@param type the type of the added side data
@param buf an AVBufferRef to add as side data. The ownership of
the reference is transferred to the frame.
@return newly added side data on success, NULL on error. On failure
the frame is unchanged and the AVBufferRef remains owned by
the caller.
Add a new side data to a frame from an existing AVBufferRef
@param frame a frame to which the side data should be added @param type the type of the added side data @param buf an AVBufferRef to add as side data. The ownership of the reference is transferred to the frame.
@return newly added side data on success, NULL on error. On failure the frame is unchanged and the AVBufferRef remains owned by the caller.