VIDEO_FRAME_INPRG
!test_bit(VIDEO_FRAME_INPRG, &video->flags),
!test_bit(VIDEO_FRAME_INPRG, &video->flags) && empty)
set_bit(VIDEO_FRAME_INPRG, &video->flags);
clear_bit(VIDEO_FRAME_INPRG, &video->flags);
clear_bit(VIDEO_FRAME_INPRG, &video->flags);