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  1. Code:
    2pass curve failed to converge
    I saw something like this when I was using x264. Apparently, it is due to setting the target bitrate higher than necessary. I was just want to make sure... will it affect the final output?

    Edit: Sorry I can't give any more info. I'm on a different computer :/.
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  2. Yes, your final output will be smaller (lower average bitrate) than you requested.
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  3. reduce qpmin , (the minimum quantizer) and it should allow you to achieve higher bitrates

    default is 10, so try something lower e.g. --qpmin 1
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  4. What that's telling you really is that you've selected too high a bitrate for your source.
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  5. Okay, thanks. It's fine if it simply means that the target bitrate is too high (and that x264 will adjust).
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  6. Why don't you use CRF encoding? It's faster, you always get the quality you specify, and the minimum file size for that quality.
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  7. Originally Posted by jagabo View Post
    Why don't you use CRF encoding? It's faster, you always get the quality you specify, and the minimum file size for that quality.
    So, should I use crf instead of 2-pass? What are the cons of using crf?
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  8. With bitrate based encoding you select a bitrate and the file comes out with whatever quality the encoder can deliver for that bitrate. With quality based encoding (CRF) you select a quality and the file turns out with whatever bitrate is required for that quality. If you were to encode a video with CRF and it came out to some particular bitrate, then encoded the source again with a 2-pass encode at the same bitrate, the two files would look nearly identical.
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  9. Originally Posted by jagabo View Post
    With bitrate based encoding you select a bitrate and the file comes out with whatever quality the encoder can deliver for that bitrate. With quality based encoding (CRF) you select a quality and the file turns out with whatever bitrate is required for that quality. If you were to encode a video with CRF and it came out to some particular bitrate, then encoded the source again with a 2-pass encode at the same bitrate, the two files would look nearly identical.
    Alright. Is there any way to, say, deepen the analysis that crf does to determine quality?
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  10. All the same things 2-pass VBR does to deepen analysis.
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