Function plan_packet_copy 

pub fn plan_packet_copy(
    request: &PacketCopyRequest<'_>,
) -> Result<PacketCopyPlan, String>

Decides whether request can be served by copying packets.

A host planning several runs of one export uses one PacketCopyPlanner, which reads each source once.

Errors

Names why not: the container, codec, size, color, or frame timing that a copy would not reproduce, or a run that does not start at an IDR picture.