[FFmpeg-user] backtrack parameters from existing file

[Carl Eugen Hoyos]

Scott Goldman <scottg <at> emailhosting.com> writes:

> So i've discovered what my issue really is. I'm trying to transcode from
> an MXF file created by QUANTEL 3.6.  This version of their power portal
> incorrectly set the edit rate as 59.97 but is in really 29.97.  so my
> transcode is running at double speed. 

Please provide a sample if this is reproducible with FFmpeg.

> I would like to use the -r 29.97
> before the -i, but that doesnt work and when i add -force_fps -r 29.97,
> ffmpeg reports Option framerate not found.

This is a (common) misunderstanding:
MPlayer used to rely on the framerate to calculate 
timestamps, FFmpeg mostly only provides the frame-rate 
for informational purpose (there are exceptions, but 
mxf is not one of them).

Or in other words: You cannot fix this problem by 
providing an option, please test ffmpeg and if 
it fails, please provide complete, uncut 
console output (and a sample).

Carl Eugen