From 327f3fc848e6e30d431411e103e10dbae7f461e3 Mon Sep 17 00:00:00 2001 From: wm4 Date: Fri, 24 May 2019 20:09:52 +0200 Subject: manpage: document why Vorbis backward playback does not work The only reasonable solution to this is probably to make discarding of preroll frames based on timestmaps, instead of frame/packet count. But then you get issues with video and its dumb timestamp reordering. So for now, fuck it. --- DOCS/man/options.rst | 7 +++++++ 1 file changed, 7 insertions(+) (limited to 'DOCS') diff --git a/DOCS/man/options.rst b/DOCS/man/options.rst index 0631fd6a12..f2b94a7e1e 100644 --- a/DOCS/man/options.rst +++ b/DOCS/man/options.rst @@ -489,6 +489,13 @@ Playback Control A workaround is to remux to a format like mkv, which enforces packet boundaries. Making mpv cache the entire file in memory also works. + - Backward playback with Vorbis does not work. libavcodec's decoder + discards the first Vorbis packet (after each decoder reset), and the + mechanism behind ``--audio-reversal-buffer`` assumes that it strictly + outputs a frame for each packet fed to it (the mechanism discards output + based on frame count, not timestamps). Since this tries to decode each + frame on its own, the player never gets a usable audio frame. + Tuning: - Remove all ``--vf``/``--af`` filters you have set. Disable deinterlacing. -- cgit v1.2.3