.mp4 demux / Lavf58.76.100 error ?

[kalemvar1]

I'm performing demux on some files using ffmpeg with this command line :

ffmpeg.exe -i videoWithAudio.mp4 -c:v copy -an videoWithoutAudio.mp4

The result is good but there's some change within the metadata (before+after)

=====
Original
=====

Duration : 1 h 28 min
Bit rate : 7 732 kb/s
Maximum bit rate : 20.1 Mb/s
Width : 1 920 pixels
Height : 1 080 pixels
Display aspect ratio : 16:9
Frame rate mode : Constant
Frame rate : 25.000 FPS

====
Demux
====

Duration : 1 h 28 min
Source duration : 1 h 28 min
Bit rate : 7 421 kb/s
Maximum bit rate : 7 732 kb/s
Width : 1 920 pixels
Height : 1 080 pixels
Display aspect ratio : 16:9
Frame rate mode : Constant
Frame rate : 25.000 FPS

----------------------------

During the demux, the "maximum bitrate" is alter and the "source duration" is added.

looking at the metadata, Lavf58.76.100 is used with ffmpeg, can this be the problem ? or it's something else ?

Thanks

kalemvar

[ProWo]

Your commandine isn't a demux, but a REmux (mp4 to mp4). The modified metadata are written by the ffmpeg mp4 muxer.

[kalemvar1]

Thanks for the reply

do you have a suggestion of demux command line ? that would be really helpful

Thanks

[ProWo]

I think the maximum bitrate of the remuxed file is correct.