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View Full Version : cutting/muxing and filesizes


PeeJayNL
21st March 2002, 14:52
I encoded a 89 minute dvd svcd compliant using CCE@cbr2000/224 audio
I ended up having an 1.4 gig MPV and and 150mb MP2.
Did various multiplexing using BBmpeg, with the following results :
* complete MUX --> mpg filesize 1.96 gig
* MUX start 0 end 60 (e.g 1 min)--> mpg filesize 17.99 mb
* MUX start 0 end 240 (e.g 4 min)--> mpg filesize 83.75 mb.

-first I would expect the complete mux to be the summa of the MPV/Mp2
-second if 1 minute is to result in a 18 mb file, i expect 4 mins to be appx 64 mb and 90 mins appx 1.6 gig.

Seems as the input file size grows, the output file size doesn't grow linear but more exponential.
Is this a normal thing to happen with muxing ?

Boulder
21st March 2002, 16:47
It seems that CBR doesn't actually have a constant bitrate in CCE.

The filesize also might vary because of the headers in it? I'm not sure, but I'd suspect something like that.