case MODE_DROP_ODD: /* only output even frames, odd frames are dropped; height unchanged, half framerate */
case MODE_DROP_EVEN: /* only output odd frames, even frames are dropped; height unchanged, half framerate */
out = av_frame_clone(tinterlace->mode == MODE_DROP_EVEN ? cur : next);
case MODE_DROP_ODD: /* only output even frames, odd frames are dropped; height unchanged, half framerate */
case MODE_DROP_EVEN: /* only output odd frames, even frames are dropped; height unchanged, half framerate */
out = av_frame_clone(tinterlace->mode == MODE_DROP_EVEN ? cur : next);