This function fills @info with the #GstMapInfo of @length merged memory blocks
starting at @idx in @buffer. When @length is -1, all memory blocks starting
from @idx are merged and mapped.
@flags describe the desired access of the memory. When @flags is
#GST_MAP_WRITE, @buffer should be writable (as returned from
gst_buffer_is_writable()).
When @buffer is writable but the memory isn't, a writable copy will
automatically be created and returned. The readonly copy of the buffer memory
will then also be replaced with this writable copy.
The memory in @info should be unmapped with gst_buffer_unmap() after usage.
This function fills @info with the #GstMapInfo of @length merged memory blocks starting at @idx in @buffer. When @length is -1, all memory blocks starting from @idx are merged and mapped.
@flags describe the desired access of the memory. When @flags is #GST_MAP_WRITE, @buffer should be writable (as returned from gst_buffer_is_writable()).
When @buffer is writable but the memory isn't, a writable copy will automatically be created and returned. The readonly copy of the buffer memory will then also be replaced with this writable copy.
The memory in @info should be unmapped with gst_buffer_unmap() after usage.