[FFmpeg-user] How to retain correct frame order when concatenating?

[Bouke / edit 'B]

> On 29 Oct 2024, at 13:39, Flopsy <flopsy at tfwno.gf> wrote:
> 
> Hi!
> 
> I'm trying to concatenate these two single frame videos [https://files.catbox.moe/v85pqy.zip], but they always end up in the wrong order.
> 
> I've tried with the following command:
> 
>> ffmpeg -y -f concat -i filelist.txt -c copy outf.mkv
> 
> ...where filelist.txt contains:
> 
>> file '0012890a_9680.mkv'
>> file '0012890a_692070.mkv'
> 
> But this gives me a 2 frame video with the frame order reversed. Examining the file with `ffprobe -show_frames`, it does indeed show the frames in reverse (some lines omitted):

Smells like someone is soring by alphabet.

Test it yourself after renaming the files 0001.mkv and 0002.mkv
See what happens then.

No clue, but gut feeling tells me…

Bouke