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  1. I am trying to encode a 4 episode Blu-Ray of mine and I am noticing something I have not come across before.

    3 of the 4 episodes encode just fine and at the bitrate I chose in the settings. They come out the exact file size the bitrate calculator said they would as usual. The 4th episode however, is always encoding at a lower bitrate and the file size is not what I specified it to come out at. It simply refuses to come out as the other episodes do.

    Mediainfo is showing the data like this
    7386Kbps (9563 Kbps)

    The other 3 episode simply show up as 9563Kbps and are the file size they are supposed to be. I have not come across a second number that is in (parenthesis) before.


    I would not mind it if the file size was not almost 300MB less in size than it should be. I am getting the impression that most of the video is in the 7000's instead of where I set it at.

    Why is this one episode giving me this kind of problem? I been using these encoder settings for years and have never had this happen to an encode before.
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  2. If it helps any, all 4 episodes are one long .m2ts file with 4 episodes connected together. I chose specific frames in the 4 scripts to get each one separated in the video and audio output.

    The other 3 are the same encoder settings and from the same video source, so why is this one doing this? It is roughly the same exact length as the other 3 episodes, a second or two difference at most. It's also roughly the same source quality since its all in the same .m2ts file.

    I am confused as to why I am having this issue and cannot get it to encode at the bitrate and file size I specified like everything else I encode.
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  3. When a video isn't "complex" enough an encoder cannot reach the requested average bitrate. Especially if you are limiting quantizers, peak bitrate, etc.
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  4. Originally Posted by jagabo View Post
    When a video isn't "complex" enough an encoder cannot reach the requested average bitrate. Especially if you are limiting quantizers, peak bitrate, etc.
    It's from the same exact source though, just different selected frames. Why would only that piece of it not be complex enough??

    I'm not limiting anything more than I ever have before that I am aware of. I have always used these settings for 1080p material and its always encoded at the bitrate I chose just fine.

    program --preset slow --pass 2 --bitrate 9563 --stats ".stats" --deblock 1:1 --qpmin 10 --qpmax 28 --vbv-maxrate 25000 --subme 7 --partitions all --trellis 2 --psy-rd 0.40:0 --no-dct-decimate --no-fast-pskip --colorprim bt709 --output "output" "input"


    Would lowering the min qpmin from 10 help?
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  5. Originally Posted by killerteengohan View Post
    It's from the same exact source though
    It's not the exact same source, it's a different episode. Different episodes of the same series often have very different bitrate requirements.

    Originally Posted by killerteengohan View Post
    Code:
    --pass 2
    Did you accidentally use the stats from from another video?

    Originally Posted by killerteengohan View Post
    Code:
    --qpmin 10
    Would lowering the min qpmin from 10 help?
    Maybye.

    Originally Posted by killerteengohan View Post
    Code:
    --vbv-maxrate 25000
    Limiting the bitrate can also be a cause of missing the bitrate target.
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  6. Originally Posted by jagabo View Post
    Originally Posted by killerteengohan View Post
    Code:
    --vbv-maxrate 25000
    Limiting the bitrate can also be a cause of missing the bitrate target.
    25000 is not high enough? That's more than am I am encoding at by over 2x more. Megui claims this is just for buffering.
    Last edited by killerteengohan; 5th Jul 2018 at 08:56.
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  7. It looks like lowering the qpmin to 8 which is allowing it to use even more more bitrate than crf 10 did the trick. I find it weird that I have never had this happen before in all the years I have been encoding. Why it decides to be picky with this one episode is beyond me.

    Thanks for the bit of info I gathered from your replies.
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