[FFmpeg-user] Will ffmpeg always use the existing orig.parameters when no new are specified on cmdline for re-encoding?

[Moritz Barsnick]

On Thu, Oct 25, 2018 at 14:23:37 +0200, Ben wrote:
> When I enter at the command line a ffmpeg command and specify (beside input and output file name) only the new video bitrate:
> Will ffmpeg ALWAYS automatically take the remaining parameters from the existing video?
> 
> In otehr words: Will e.g. the frames per second, the max keyframe interval, the resolution, the audio bitrate and codec always be the same as the original?

FPS; Yes, if possible. Depends on input and output formats (and
possibly other stuff).

Key frame interval: no.

Resolution: yes.

Bitrates and codecs: No.

ffmpeg does not have such a mode. Some wrapper tools or GUIs may
though.

> If not: Can I tell ffmpeg explicitely, manually to use them? Similar to
> ffmpeg.exe -i ....  -b:v 2200k -useotherparmsfrominput ......

No.

Moritz