GNOME Bugzilla – Bug 769624
videorate: Does not support reverse playback
Last modified: 2016-08-19 12:58:06 UTC
Created attachment 332935 [details] ges-testcase.c See attached testcase. The ">>" button seeks to the middle of the clip with rate=-1.0 and should play to the beginning... it seems to seek to the middle but never renders anything.
Created attachment 332936 [details] GST_DEBUG=nle*:6 log
Problem is that we use videorate in ges-video-source.c, as it does not support reverse playback apparently.
That is not impressive videoarte does not supported it! Also compositor does not either afaict so we it will fail if mixing is enabled. What do you propose?
I'm implementing it in videorate because I don't need it with mixing support. compositor would be relatively simple though (basically the same as videorate), but audiomixer is a bit more interesting :)
Created attachment 333550 [details] [review] videorate: Implement basic support for reverse playback This is enough for making it work in GES, but it's unclear if all the various property combinations are working correctly. It's an improvement over what was there before in any case, which was to just drop all buffers if rate < 0.0.
Created attachment 333553 [details] ges-testcase.c Updated testcase. To switch from reverse playback, you need to do a seek that ensures to reset the stop position (GST_SEEK_TYPE_NONE for the stop position won't) to something meaningful.
Going to merge the videorate fix soon if nobody has any objections
commit 2ebbd1c9fafdca09d482fe84feececd929d8bee8 Author: Sebastian Dröge <sebastian@centricular.com> Date: Thu Aug 18 12:03:39 2016 +0300 videorate: Implement basic support for reverse playback This is enough for making it work in GES, but it's unclear if all the various property combinations are working correctly. It's an improvement over what was there before in any case, which was to just drop all buffers if rate < 0.0. https://bugzilla.gnome.org/show_bug.cgi?id=769624