[FFmpeg-user] Image extraction broken with ffmpeg, but not with mencoder. How can I fix this?

Paul B Mahol onemda at gmail.com
Mon Sep 2 22:33:31 CEST 2013


On 9/2/13, James Board <jpboard2 at yahoo.com> wrote:
>>> The image2 muxer documentation doesn't mention this.  How do I
>>> specify an input frame rate (24000/1001) for the above command?
>
>>
>>You need it for whatever reads images not for creating them....
>
> No.  The program which reads the images doesn't care what the frame rate
> is.
>
> I am not using ffmpeg to read the images.  When I use the select filter, I
> use it on the same AVI video file that I used to
> create the images.
>
>>> Also, I have a huge edit list which took 4 hours to generate.  Is there
>>> some formula I can use which will convert the frame numbers that ffmpeg
>>> used as output for the jpeg images to the  equivalent frame numbers that
>>> ffmpeg
>>> will use as input to the select filter?
>>
>>Use same frame rate for input as for output, its simple enough.
>
> What?  But that won't solve the problem.  Here is the problem again.
> I used ffmpeg to generate image files from an AVI video.  The frame
> numbers on those image files are incorrect.  Unfortunately, I used those
> image files to generate edit lists and those edit lists won't work because
> of the ffmpeg bug in generating the image files.
>
> The problem is that ffmpeg uses one formula for numbering frames when
> it outputs images and it uses another formula for numbering frames when it
> uses the select filter.  I just want to know what the formulas are so I can
> convert the frame numbers that ffmpeg used when creating the image files
> to the frame numbers that ffmpeg will later use with the select filter.
> Then
> I can compensate for the ffmpeg bug, and my edits will be frame exact.

Sorry, but how can I reproduce that bug?


More information about the ffmpeg-user mailing list