[FFmpeg-user] DPX image sequence conversion issue

[Phil Turmel]

On 01/03/2014 03:04 PM, Stuart Bruce wrote:
> I've come across an issue which is either my human error or an FFmpeg
> bug, and I'm not sure which.
> 
> I've got an image sequence of 150 DPX files, and I need to create a
> lo-res h264 MOV from them.
> 
> When I set the rate to 25fps, it works absolutely fine. The resulting
> file appears as 150 frames in QuickTime Player.
> 
> However when I change to 24fps (-r 24), which is what it should be for
> this particular footage, the resulting file only has 146 frames in it.
> Both FFprobe and QuickTime Player report that the resulting file has 146
> frames, even though it's the same source image sequence of 150 frames.
> There's no apparent error that I can see.
> 
> I haven't changed anything else about the command line except the rate.

Image sequences have an implied input rate of 25fps.  Look at the cut
part of your output to see that.  ffmpeg was faithfully dropping input
frames to convert 25 fps to 24 fps.

use "-r 24" for both input and output options to solve this.

Usage summary:

ffmpeg [input options] -i inputfile [output options] outputfile

HTH,

Phil