if (_finish || _queued_full_in_memory > _maximum_frames_in_memory || have_sequenced_image_at_queue_head ()) {
/* We've got something to do: go and do it */
if (_finish || _queued_full_in_memory > _maximum_frames_in_memory || have_sequenced_image_at_queue_head ()) {
/* We've got something to do: go and do it */