I want to split a file by file size but as I can not find that option I
thought of doing it by calculating the size using the bitrates. The
problem is that when I split a file with the command line tool i
receive different bitrates. I use this code to split the file:
all frames have different sizes depending on the content’s complexity
and groups of pictures have different sizes mostly depending on how
quickly the image changes. That’s why the bitrate varies over time and
every part (split) of the video has a different bitrate. The overall
bitrate is an average of all individual bitrates (weighted by duration
of the splits).
You can limit the file size of one part with the -fs option, but you
know only afterwards how long it got. And then you can use this duration
to start the next part from this point in time.