ffmpeg change FPS tag/info without re-encoding

[geextah_2]

Hi, the third time I noticed weird framepacing issues on my TV. There is a stutter each second. I looked into these files with MediaInfo and noticed that these movies have 2 different FPS tags. All other movies have only one tag/FPS info. Sorry for the language, I tried to change it to ENG but that didn't work. The first line says "Framerate" and the 2nd line says original "Framerate" So my PC plays this fine without jitter at 25 FPS and my TV plays it wrong with 23,976. I encoded the file with 25FPS and it worked fine on my TV.
1. Is there a way to remove this "tag" without re-encode with ffmpeg?
2. Does anyone know why there are 2 FPS infos/tags? As mentioned this is the third time I encountered this behaviour, so this is not a "corrupted file" case. The movies were encoded this way.

Thanks for any help



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[ProWo]

You can use clever Ffmpeg-GUI for this.
Load your video, click main, click various, click fix framerate, enter 25 in the fps field and execute the command.
No reencode is done, only streamcopy, so it's fast, with no quality loss.

[Sharc]

2. Does anyone know why there are 2 FPS infos/tags? As mentioned this is the third time I encountered this behaviour, so this is not a "corrupted file" case. The movies were encoded this way.

Probably a conflicting info between stream and the container.

[geextah_2]

I have found a fix with MKVToolNix. (Give the FPS and check the box below) But knowing a way without GUI in ffmpeg would be also nice to know


[Attachment 77866 - Click to enlarge]

[JN-]

Does anyone know why there are 2 FPS infos/tags?

I noticed similar when I converted the supplied vfr clip ( "Problem Section Exported to H.264" ) to cfr in this thread ...
https://forum.videohelp.com/threads/413536-The-H264-Codec-in-Premiere-Pro-CS6-Creates-...le-Frame-Rates

This is a screenshot of the mediainfo of the vfr file on the left and the cfr converted file on the right.

Is it possible the OP's file was originally VFR ?

[geextah_2]

a person on reddit told me
"Frame rate is the frame rate for playback by a player.
Real frame rate is the frame rate used during capture (should have been called "Capture frame rate"), so the one in the reality."

[Luke M]

For AVC:

FOR %%G IN (*.mkv) DO mkvmerge -o "%%~nG 25fps.mkv" --default-duration 0:25p --fix-bitstream-timing-information 0:1 "%%G"

or

FOR %%G IN (*.mkv) DO ffmpeg -i "%%G" -map 0 -c copy -bsf:v h264_metadata=tick_rate=50:fixed_frame_rate_flag=1 "%%~nG 25fps.mkv"

For HEVC:

FOR %%G IN (*.mkv) DO ffmpeg -i "%%G" -map 0 -c copy -bsf:v hevc_metadata=tick_rate=25:num_ticks_poc_diff_one=1 "%%~nG 25fps.mkv"

[JN-]

Is that a typo in the middle ? rate = 50.

[Ennio]

I have found a fix with MKVToolNix. (Give the FPS and check the box below) But knowing a way without GUI in ffmpeg would be also nice to know

Note that in MTX this works only for AVC streams. HEVC isn't supported (yet?).

Other than fixing timestamps using clever FFmpegGUI, it's possible to do it directly with ffmpeg.exe cli.
As an example, to rewrite timestamps for "23.976" fps HEVC, do

ffmpeg -i input.hevc -c copy -bsf:v hevc_metadata=tick_rate=(24000/1001):num_ticks_poc_diff_one=1 output.hevc