[FFmpeg-user] concatenate png files for different durations?

[Lou]

On Sun, 16 Mar 2014 14:35:54 -0700
Spencer Graves <spencer.graves at prodsyse.com> wrote:

>        Thanks for the reply.  Unfortunately, I've been unable so far to 
> make it work.  Consider the following:
> 
> 
>  >ffmpeg -y concat -i concat1.txt tst2e.mp4

Your forgot -f as in:

ffmpeg -y -f concat -i concat1.txt tst2e.mp4