[FFmpeg-user] ffmpeg ignores duration and skips concat images

Carl Eugen Hoyos cehoyos at ag.or.at
Mon Jun 16 17:01:42 CEST 2014

Simon Thelen <ffmpeg-user <at> c-14.de> writes:

> > ffmpeg -framerate 1 -i png.other/%04d.png out.mkv
> Ok, that fixed it. out.mkv now contains all the frames it 
> should.

> I'm not entirely sure why though. If I read the manpages 
> correctly, that -framerate option controls a setting for 
> the image2 demuxer while the -r works globally for all 
> input streams, but why would -r work when the images are 
> all the same size and not when they're different sizes?

-r is an option that makes the input constant frame rate 
while -framerate changes its speed.
One could argue that this isn't really the thieves' fault 
(I consider the "new" meaning of "-r" a hack but it is 
sometimes useful), but given that it has fooled everybody 
in this mailing list thread, it is at least not completely 

> I attached the output of the working command in case 
> you're interested, but it looks basically the same 
> as the output for the commands that didn't work.

Fortunately it looks very different here;-)

An unrelated comment:
Please remember that gcc binaries with a "0" or "1" in 
their version numbers should never be used and that 
gcc 4.9.0 is particularly buggy.

Carl Eugen

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