2018-03-08 22:20 GMT+01:00, Mark Burton <[email protected]>: > On 8 Mar 2018, at 17:21, Carl Eugen Hoyos <[email protected]> wrote: >> You need a compiler, make and git. Iirc, all three are installed if you >> type something like "gcc -v" on the command line (but I assume they >> are now installed by brew). > > Thank you very much! That filled in a few blanks for me and I was able to > get it all working. So I built from the current git and tested the ffmpeg > build. The timescale issue was still the same, with inaccurate seeking. > > Then in movenc.h I changed MOV_TIMESCALE from 1000 to 24000 and built ffmpeg > again. This time the output .mov worked, with no seeking issues! > > Finally in movenc.h I changed MOV_TIMESCALE to 600 and built ffmpeg again. > Again, the output .mov worked, with no seeking issues! > > I imagine some exhaustive testing is needed for other workflows, and I’m > obviously not aware yet of why 1000 was chosen for ffmpeg (??), but based on > the Quicktime specification documents and what the default timescale is set > to there, it would seem that a switch from 1000 to 600 could be a very > positive change.
> Please could you advise what I would need to do from here to move things > forward. One possibility is that you run "git diff libavformat/movenc.h" to verify you have only changed this one value (this assumes you have originally done "git clone" and not "curl..."), then run "git commit libavformat/movenc.h" to start the commit line editor, type "i" (I believe this will be necessary to get into insert mode) and "lavf/movenc: Change MOV_TIMESCALE to 600" followed by two (!) carriage returns and an explanation why this is a good idea (because seeking works better in some other software), then exit the editor (it's "ESC" ":wq" here) and get back to the shell. There, run "git format-patch HEAD^" to get a file 0001-lavf-movenc... that you send as attachment to the ffmpeg-devel mailing list and "git reset HEAD^" to clean your local checkout. Carl Eugen _______________________________________________ ffmpeg-user mailing list [email protected] http://ffmpeg.org/mailman/listinfo/ffmpeg-user To unsubscribe, visit link above, or email [email protected] with subject "unsubscribe".
