ffmpeg fine concatenation does not work

[peterdolson]

I execute the following command line for ffmpeg.exe
-i C:\Beema\video-source\DO_U_BEEMA176x144short.avi
-i C:\Beema\video-source\DO_U_BEEMA176x144short.avi
-i C:\Beema\temp\9016730-51056331-stitcheds.avi
-i C:\Beema\video-source\GOTTA_BEEMA176x144short.avi
-y -ac 1 -r 24 -b 25K
C:\Beema\video-out\9a062fb6-d448-48fe-b006-a85d51adf8a1.mpg

The output file in video-out ends up having a single copy of DO_U_BEEMA. I do not understand why ffmpeg is not concatenating.

Any help is dramatically appreciated,

[Chris K]

You cannot concatenate with FFmpeg.

Use a small Avisynth script like;

AVISource("C:\Beema\video-source\DO_U_BEEMA176x144short.avi ") + \
AVISource("C:\Beema\video-source\DO_U_BEEMA176x144short.avi ") + \
AVISource("C:\Beema\temp\9016730-51056331-stitcheds.avi ") + \
AVISource("C:\Beema\video-source\GOTTA_BEEMA176x144short.avi ")

Then use that as source for FFmpeg.

[peterdolson]

Thanks. I thought that was true, but doing some googling led me to believe that you could concatenate.

Appreciate the feed back.

[Chris K]

Thanks. I thought that was true, but doing some googling led me to believe that you could concatenate.

Yeah found this, but that's still not FFmpeg that does it.

You can also use ffmpeg to concatenate multiple videos into one long video. Start by transcoding all the individual videos into MPEG format, all with exactly the same bit rates, codecs, image resolutions, frame rates etc. Mistakes can be avoided by using one of ffmpeg's predefined targets such as ntsc-dvd or pal-dvd. Once that's done, simply string the resulting .mpg files together using "cat" and redirect the output to another .mpg file. Now, the timestamps inside the resulting, big .mpg file are all going to be messed up, so you'll have to process the big .mpg file with ffmpeg again. This will have the effect of putting the timestamps right.

It's joining the files with a dos command and FFmpeg gets still only one single file.
You probably need to add "-fflags genpts" to the command line to get the time stamps right.

I would trust on Avisynth much more to do the job decently. If you found other approaches with FFmpeg, please let me know.