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MPEG4 Bitrate effect on processor load..
I thought I saw this somewhere in the past, but maybe I'm just demented. What
effect does increasing the bitrate have on the processor when doing MPEG4
encoding. For example, say you have a low end machine doing both front and
backend duties and you're trying to optimize overnight recordings. Assuming 320
x 480 capture resolution as a constant, does higher bitrate equate to less
processor work and therefore less likely to have lost frames but at the same
time give you larger files? (i.e. less compression == less work?)

--
"Testing proves testing works." - Dave Thomas

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Re: MPEG4 Bitrate effect on processor load.. [ In reply to ]
Kevin J. Slater wrote:
> I thought I saw this somewhere in the past, but maybe I'm just demented. What
> effect does increasing the bitrate have on the processor when doing MPEG4
> encoding. For example, say you have a low end machine doing both front and
> backend duties and you're trying to optimize overnight recordings. Assuming 320
> x 480 capture resolution as a constant, does higher bitrate equate to less
> processor work and therefore less likely to have lost frames but at the same
> time give you larger files? (i.e. less compression == less work?)

This has come up in the past and it is a fair question.
A higher bitrate for MPEG4 uses more CPU time to calculate
all the bits it needs to write out. However, increasing
the bitrate by 20% doesn't increase the CPU usage nearly
as much as increasing the resolution by 20%. If you're CPU
bound, lower res with a higher bitrate with give you more
bang for the buck.

-- bjm