Find the #GstVideoRegionOfInterestMeta on buffer with the given id.
Buffers can contain multiple #GstVideoRegionOfInterestMeta metadata items if multiple regions of interests are marked on a frame.
a #GstBuffer
a metadata id
the #GstVideoRegionOfInterestMeta with id or null when there is no such metadata on buffer.
Find the #GstVideoRegionOfInterestMeta on buffer with the given id.
Buffers can contain multiple #GstVideoRegionOfInterestMeta metadata items if multiple regions of interests are marked on a frame.