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  1. Hi

    Target quantizer goes from 1 to 31. Is there a chart that tells us to what bitrate these "presets" correspond?

    For example, target quantizer default is 4.0. What bitrate is that?

    Thanks
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  2. Originally Posted by drgt View Post
    Is there a chart that tells us to what bitrate these "presets" correspond?
    No, it'll use whatever bitrate it needs for the quality you set. A video of a guy reading the news will need a much lower bitrate for Quant 4 than will a more complex video - of a storm, say. There's no way to know the bitrate needed or the final size when doing one-pass quality encodes since the compressibility of video sources can vary greatly.
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  3. Look at clean.avi and noise.avi from this post:

    https://forum.videohelp.com/threads/295672-A-problem-for-video-experts?p=1811057&viewfu...=1#post1811057

    Both are the Belle Nuit test pattern, one with noise, one without. Both were compressed at Target Quantizer 4 with the same settings. The noisy video required 20 times more bitrate. The disparity would have been even bigger if the clips had been longer.

    With quantizer based encoding you know what the quality of the video will be but you don't know what the bitrate will be. With bitrate based encoding you know what the bitrate will be but you don't know what the quality will be.
    Last edited by jagabo; 19th Sep 2010 at 08:07.
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  4. Got it. Thanks a lot.
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