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  1. Member
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    virtualDub.





    Which one will produce a higher quality and which one will be quicker?



    Do u think by using mutiple passes on a video but with a lower bitrate it will encide the video faster with high quality or just a single pass but with high bitrate.


    I apologise because i really lack experience in this. I am hoping to encode a vid with bitrate of 8000Kbps in 1 and a half hr.
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  2. I'm assuming you are using x264 as a continuation of your other threads

    your only real option is 2pass vbr for bitrate control

    a 1pass abr will give you very poor quality, and still might overshoot/undershoot

    a 1pass crf will give you good quality, but unpredictable bitrate or filesize

    there is no chance of encoding (i'll assume a 45min section) it in 90min with your system, unless you use abr with very low quality settings
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    Originally Posted by poisondeathray
    I'm assuming you are using x264 as a continuation of your other threads

    your only real option is 2pass vbr for bitrate control

    a 1pass abr will give you very poor quality, and still might overshoot/undershoot

    a 1pass crf will give you good quality, but unpredictable bitrate or filesize

    there is no chance of encoding (i'll assume a 45min section) it in 90min with your system, unless you use abr with very low quality settings

    Thanks for this.


    I tested it using an 8000 bitrate and it's quite good. Vdub estimates the time taken to encode this will be like 4hrs.



    U suggest a double pass. So it's double pass at 8000 brate? Will it take twice as long?
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  4. No, the first pass is an analysis pass, if you use "turbo" settings it will be much faster than the 2nd pass with negligible impact on quality

    You don't want to spend 4-5hours only to find out you oversized it... LOL. Use 2pass VBR.
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    Originally Posted by poisondeathray
    No, the first pass is an analysis pass, if you use "turbo" settings it will be much faster than the 2nd pass with negligible impact on quality

    You don't want to spend 4-5hours only to find out you oversized it... LOL. Use 2pass VBR.

    It won't be over sized because i lowered the bitrate already.


    The thing i am concerned about now is speed.



    With 2 passes at 8000 bitrate will it still take 4 hrs?

    Or i lower the bitrate with 2 pass and it s faster?
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  6. Yes using a lower bitrate will speed up encoding a bit, using lower quality settings will speed it up too

    I don't know how long it will take. Just do it overnight. Quit worrying about how long it will take. Or buy the blu-ray
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    i am trying out multiple pass with 5k bitrate vs 8k bitrate single which takes more than 4hrs.


    I would assume that 5k mutiple pass would obviously be faster than 8k and have the same quality.
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  8. Originally Posted by jones24
    i am trying out multiple pass with 5k bitrate vs 8k bitrate single which takes more than 4hrs.


    I would assume that 5k mutiple pass would obviously be faster than 8k and have the same quality.

    Not even close
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    Originally Posted by poisondeathray
    Yes using a lower bitrate will speed up encoding a bit, using lower quality settings will speed it up too

    I don't know how long it will take. Just do it overnight. Quit worrying about how long it will take. Or buy the blu-ray


    Of course lower bitrate will speed it up. I am just comparing the 2.


    Mutiple pass takes longer and since it goes thru analysis but if it speeds things up with a lower bitrate with the same quality i would take it.


    When encoding vids 1 should know the diffs.

    I am quite disappointed that someone with more experience can tell me the diff. I have to try it out myself.


    If the answer is buy the blu ray or the dvd, there's not much purpose for this forum. True some ppl need to edit home made vids but most of them would be talking about movies and stuff.
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    I tested it out 5K bitrate multi vs 8k single quality wise 5k multi is as good as the original 9.1k.


    Now it's the time. Multi pass has no time stated.
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  11. Originally Posted by jones24
    I tested it out 5K bitrate multi vs 8k single quality wise 5k multi is as good as the original 9.1k.
    Not likely.
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    Originally Posted by jagabo
    Originally Posted by jones24
    I tested it out 5K bitrate multi vs 8k single quality wise 5k multi is as good as the original 9.1k.
    Not likely.


    That's what i saw after i finished encoding part of the file.

    Now it's the time taken.
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  13. Originally Posted by jones24
    Originally Posted by jagabo
    Originally Posted by jones24
    I tested it out 5K bitrate multi vs 8k single quality wise 5k multi is as good as the original 9.1k.
    Not likely.
    That's what i saw after i finished encoding part of the file.
    Look closer.
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    Originally Posted by jagabo
    Originally Posted by jones24
    Originally Posted by jagabo
    Originally Posted by jones24
    I tested it out 5K bitrate multi vs 8k single quality wise 5k multi is as good as the original 9.1k.
    Not likely.
    That's what i saw after i finished encoding part of the file.
    Look closer.

    yup i saw it up close and i even compared by watching one first then the other. Looks the same. In fact the 5k one looked better.
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  15. What you are suggesting is simply impossible, mathematically and otherwise

    You are use a lossy format. Even if you double the bitrate @ 20Mbps it would look worse than the 9Mbps "original". Details are lost every generation, and compression artifacts accrue

    Perhaps you have a low quality display?

    All that really matters is if you *think* so...
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    Originally Posted by poisondeathray
    What you are suggesting is simply impossible, mathematically and otherwise

    You are use a lossy format. Even if you double the bitrate @ 20Mbps it would look worse than the 9Mbps "original". Details are lost every generation, and compression artifacts accrue

    Perhaps you have a low quality display?

    All that really matters is if you *think* so...

    Mine is not low quality. I am wtaching using a HD screen. Even if it really is low quality if it can make a encoded film with lower brate look better what does that mean?
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