diff options
| -rw-r--r-- | DOCS/man/options.rst | 20 | ||||
| -rw-r--r-- | etc/builtin.conf | 1 | ||||
| -rw-r--r-- | options/options.c | 1 | ||||
| -rw-r--r-- | options/options.h | 1 | ||||
| -rw-r--r-- | player/video.c | 12 |
5 files changed, 31 insertions, 4 deletions
diff --git a/DOCS/man/options.rst b/DOCS/man/options.rst index 8d916ea849..c2180fd7e7 100644 --- a/DOCS/man/options.rst +++ b/DOCS/man/options.rst @@ -679,6 +679,26 @@ Video ``--vo=vdpau`` has its own code for the ``vo`` framedrop mode. Slight differences to other VOs are possible. +``--video-latency-hacks=<yes|no>`` + Enable some things which tend to reduce video latency by 1 or 2 frames + (default: no). Note that this option might be removed without notice once + the player's timing code does not inherently need to do these things + anymore. + + This does: + + - Use the demuxer reported FPS for frame dropping. This avoids that the + player needs to decode 1 frame in advance, lowering total latency in + effect. This also means that if the demuxer reported FPS is wrong, or + the video filter chain changes FPS (e.g. deinterlacing), then it could + drop too many or not enough frames. + - Disable waiting for the first video frame. Normally the player waits for + the first video frame to be fully rendered before starting playback + properly. Some VOs will lazily initialize stuff when rendering the first + frame, so if this is not done, there is some likeliness that the VO has + to drop some frames if rendering the first frame takes longer than needed. + + ``--display-fps=<fps>`` Set the display FPS used with the ``--video-sync=display-*`` modes. By default, a detected value is used. Keep in mind that setting an incorrect diff --git a/etc/builtin.conf b/etc/builtin.conf index 79a5414a35..65b8f9e1f0 100644 --- a/etc/builtin.conf +++ b/etc/builtin.conf @@ -52,6 +52,7 @@ demuxer-lavf-probe-info=nostreams # avoid probing unless absolutely needed demuxer-lavf-analyzeduration=0.1 # if it probes, reduce it video-sync=audio # DS currently requires reading ahead a frame interpolation=no # requires reference frames (more buffering) +video-latency-hacks=yes # typically 1 or 2 video frame less latency # Compatibility alias (deprecated) [opengl-hq] diff --git a/options/options.c b/options/options.c index 878f7be12f..ebccc5976f 100644 --- a/options/options.c +++ b/options/options.c @@ -608,6 +608,7 @@ const m_option_t mp_opts[] = { {"vo", 1}, {"decoder", 2}, {"decoder+vo", 3})), + OPT_FLAG("video-latency-hacks", video_latency_hacks, 0), OPT_DOUBLE("display-fps", frame_drop_fps, M_OPT_MIN, .min = 0), diff --git a/options/options.h b/options/options.h index e76aa03db4..1c58ca14b1 100644 --- a/options/options.h +++ b/options/options.h @@ -221,6 +221,7 @@ typedef struct MPOpts { float default_max_pts_correction; int autosync; int frame_dropping; + int video_latency_hacks; double frame_drop_fps; int term_osd; int term_osd_bar; diff --git a/player/video.c b/player/video.c index b47b7293d0..e91c4ce631 100644 --- a/player/video.c +++ b/player/video.c @@ -413,13 +413,15 @@ static int get_req_frames(struct MPContext *mpctx, bool eof) if (mpctx->opts->untimed || mpctx->video_out->driver->untimed) return 1; + int min = mpctx->opts->video_latency_hacks ? 1 : 2; + // On the first frame, output a new frame as quickly as possible. // But display-sync likes to have a correct frame duration always. if (mpctx->video_pts == MP_NOPTS_VALUE) - return mpctx->opts->video_sync == VS_DEFAULT ? 1 : 2; + return mpctx->opts->video_sync == VS_DEFAULT ? 1 : min; int req = vo_get_num_req_frames(mpctx->video_out); - return MPCLAMP(req, 2, MP_ARRAY_SIZE(mpctx->next_frames) - 1); + return MPCLAMP(req, min, MP_ARRAY_SIZE(mpctx->next_frames) - 1); } // Whether it's fine to call add_new_frame() now. @@ -1149,8 +1151,10 @@ void write_video(struct MPContext *mpctx) if (mpctx->video_status < STATUS_PLAYING) { mpctx->video_status = STATUS_READY; // After a seek, make sure to wait until the first frame is visible. - vo_wait_frame(vo); - MP_VERBOSE(mpctx, "first video frame after restart shown\n"); + if (!opts->video_latency_hacks) { + vo_wait_frame(vo); + MP_VERBOSE(mpctx, "first video frame after restart shown\n"); + } } screenshot_flip(mpctx); |