[FFmpeg-user] Transcoding foscam mkv to mp4 is resulting in larger files

Carl Eugen Hoyos cehoyos at ag.or.at
Sun Sep 13 16:52:51 CEST 2015

Kai Hendry <kai.hendry <at> gmail.com> writes:

> http://s.natalian.org/2015-09-13/MDalarm_20150911_121823.mkv

This input file really is vfr (variable frame rate), 
our mov muxer requires constant frame rate, so the 
default action is to do something stupid, but a 
warning is shown that something is wrong with the 
framerate, indicating you should either specify a 
framerate with "-r" or insert the fps filter.
(The fps filter has its own shortcomings, I suggest 
using -r.)

avconv silently drops and duplicates frames, I am 
not completely convinced that this is much better: 
If people disagree, I will open a ticket.

Carl Eugen

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