[MEncoder-users] Frame Rate and file Size

[Phil Ehrens]

bruno agostini wrote:
> I understand your point and it makes sense. However in my case 2 pass
> encoding doesn't change much the final result. Futhermore vbirate=83
> with 5 fps produces a really awful quality, blocks and artefacts
> everywhere. I really need vbitrate=500.
> 
> But what I do not understand is why the codec is not able to achieve a
> higher compression rate for 5 fps. Indeed, since there is the same
> number of frame and same bitrate, changing the frame rate from 30 to 5
> fps simply means that a given frame will be displayed 6 times longer.
> But I mean, it is the same information, so okay the movie lasts longer,
> but it is exactly the same information displayed, so the codec should be
> able to produce the same file size, shouldn't it? Moreover if I produce
> a -ovc raw movie, the file size does not depend on the fps anymore...

I think what you are trying to do is not to encode at a
lower frame rate, but to play back at a lower frame rate
than what you encode at. I am not sure if there is a way
to mangle an avi header to do this or not. This may be a
better question for the transcode list than for the mencoder
list.

-- 
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