AVBuffer references backing the data for this frame. If all elements of
this array are NULL, then this frame is not reference counted.
There may be at most one AVBuffer per data plane, so for video this array
always contains all the references. For planar audio with more than
AV_NUM_DATA_POINTERS channels, there may be more buffers than can fit in
this array. Then the extra AVBufferRef pointers are stored in the
extended_buf array.
AVBuffer references backing the data for this frame. If all elements of this array are NULL, then this frame is not reference counted.
There may be at most one AVBuffer per data plane, so for video this array always contains all the references. For planar audio with more than AV_NUM_DATA_POINTERS channels, there may be more buffers than can fit in this array. Then the extra AVBufferRef pointers are stored in the extended_buf array.