|author||wm4 <wm4@nowhere>||2019-11-02 14:29:24 +0100|
|committer||wm4 <wm4@nowhere>||2019-11-02 14:29:24 +0100|
manpage: update --framedrop option
The statement about the display FPS is outdated by several years. "audio"-sync mode does not use the display FPS anymore, and that it's X11 only also isn't true anymore. These modes have separate implementations for audio and display video sync. modes, so the explanations are separate. Why the hell are users playing around with this anyway? The explanations are probably too special to make sense for anyone who doesn't know the code (and who knows the code doesn't need them anyway), but whatever.
1 files changed, 26 insertions, 10 deletions
diff --git a/DOCS/man/options.rst b/DOCS/man/options.rst
index 8ef81c642d..b778b2bc0f 100644
@@ -882,25 +882,41 @@ Video
The argument selects the drop methods, and can be one of the following:
- Disable any framedropping.
+ Disable any frame dropping. Not recommended, for testing only.
Drop late frames on video output (default). This still decodes and
- filters all frames, but doesn't render them on the VO. It tries to query
- the display FPS (X11 only, not correct on multi-monitor systems), or
- assumes infinite display FPS if that fails. Drops are indicated in
- the terminal status line as ``Dropped:`` field. If the decoder is too slow,
- in theory all frames would have to be dropped (because all frames are
- too late) - to avoid this, frame dropping stops if the effective
- framerate is below 10 FPS.
+ filters all frames, but doesn't render them on the VO. Drops are
+ indicated in the terminal status line as ``Dropped:`` field.
+ In audio sync. mode, this drops frames that are outdated at the time of
+ display. If the decoder is too slow, in theory all frames would have to
+ be dropped (because all frames are too late) - to avoid this, frame
+ dropping stops if the effective framerate is below 10 FPS.
+ In display-sync. modes (see ``--video-sync``), this affects only how
+ A/V drops or repeats frames. If this mode is disabled, A/V desync will
+ in theory not affect video scheduling anymore (much like the
+ ``display-resample-desync`` mode). However, even if disabled, frames
+ will still be skipped (i.e. dropped) according to the ratio between
+ video and display frequencies.
+ This is the recommended mode, and the default.
Old, decoder-based framedrop mode. (This is the same as ``--framedrop=yes``
in mpv 0.5.x and before.) This tells the decoder to skip frames (unless
they are needed to decode future frames). May help with slow systems,
but can produce unwatchable choppy output, or even freeze the display
- completely. Not recommended.
+ This uses a heuristic which may not make sense, and in general cannot
+ achieve good results, because the decoder's frame dropping cannot be
+ controlled in a predictable manner. Not recommended.
+ Even if you want to use this, prefer ``decoder+vo`` for better results.
The ``--vd-lavc-framedrop`` option controls what frames to drop.
- Enable both modes. Not recommended.
+ Enable both modes. Not recommended. Better than just ``decoder`` mode.