Get length memory blocks in buffer starting at idx. The memory blocks will be merged into one large gstreamer.Memory
If length is -1, all memory starting from idx is merged.
an index
a length
a gstreamer.Memory that contains the merged data of length blocks starting at idx. Use gst_memory_unref () after usage.
Get length memory blocks in buffer starting at idx. The memory blocks will be merged into one large gstreamer.Memory
If length is -1, all memory starting from idx is merged.