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  1. Maybe my questions doesn't make sense due to not understanding but please explain me what I miss because I did read posts and wiki and still it's not clear to me.
    As I understand setting low value for qmax will improve the quality by increasing the bitrate. Maybe I didn't understood something but isn't lowing the Q(quantization) will decrease the quantization levels and thus the bitrate which means degradation in quality? Or in ffmpeg lowing Q means increasing the quantization levels? If the last is true so it make sense that lower qmax improves the quality.
    If the above is true, so increasing qmax will decrease the quantization levels which means less bits for coding a quantization level. So, if number of bits for a level is lower, so total bits per frame will be lower, so how the encoder manage to get to the desired bitrate?
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  2. Originally Posted by theateist View Post
    Maybe my questions doesn't make sense due to not understanding but please explain me what I miss because I did read posts and wiki and still it's not clear to me.
    As I understand setting low value for qmax will improve the quality by increasing the bitrate. Maybe I didn't understood something but isn't lowing the Q(quantization) will decrease the quantization levels and thus the bitrate which means degradation in quality? Or in ffmpeg lowing Q means increasing the quantization levels? If the last is true so it make sense that lower qmax improves the quality.
    If the above is true, so increasing qmax will decrease the quantization levels which means less bits for coding a quantization level. So, if number of bits for a level is lower, so total bits per frame will be lower, so how the encoder manage to get to the desired bitrate?

    It's the opposite; lower quantizers yield higher bitrate and quality , the higher the quantizer the worse the quality

    Therefore, limiting qmax will prevent high quantizer values above that number (ie. will not allow very low quality frames with high average quantizer numbers)
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  3. how come that low quantization level means higher bitrate and quality? If I'll quantize it with 2 bits(meaning 4 levels) or 4 bits(16 levels) so quantizating with 4 bits will give me image more similar to original than quantizating with 2 bits, doesn't it?
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  4. Quantization isn't bits left -- it's bits taken away (figuratively, not literally).
    https://en.wikipedia.org/wiki/Discrete_cosine_transform#Informal_overview
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