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  1. Member
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    Hello fellas. You've helped me a lot before. And thank you for that.

    I am trying to compress videos off my camcoder from Mpeg-2/AAC format to x264/ogg(or aac)/mkv format.
    The problem is that I have a lot of files (around 840) and i'm trying to precess all of them at once.

    This is what I've already managed to do:
    1) I demuxed all audios (ac3) using command-line of DGIndex and created .d2v files for all 840 videos.
    2) Using simple dos command "for %f do...." I created .avs scripts for all 840 files. my typical strips looks like this:
    Code:
     LoadPlugin("c:\progra~1\Gordia~1\DgmpgDec\Dgdecode.dll") 
    LoadPlugin("c:\progra~1\Gordia~1\AvisynthPlugins\Undot.dll") 
    LoadPlugin("c:\progra~1\Gordia~1\AvisynthPlugins\TomsMoComp.dll")
    Mpeg2source("mov00375.vob.d2v")
    TomsMoComp(1,5,1)
    crop(0,0,720,576) 
    LanczosResize(576,320)
    Undot()
    3) I've also batch encoded audio's so they are ready to mux
    4) I <probably> will manage to batch mux the x264 with ogg into mkv's for all 840 files.

    This is where I need your help please
    For single file encodes I usually use Megui with unrestricted 2 pass hq preset and it works great.
    But searched and found no way to batch process all 840 .avs scripts with Megui, so I'll probably have to do this with command line x264.exe with appropriate parameters. I want and average 1200kbps for an output files. Hence couple of questions:

    Question 1)
    Is it possible to process both 2 passes with only one single dos command? (like x264.exe .... bla bla bla...) that would give me an ready .264 file? If yes, than how?
    Question 2)
    Can I use a presets from Megui, and somehow pass it as a parameter to x264.exe? If yes, than how? If no, what would be equivalent of the specific preset when in various parameters, that i pass to x264.exe?
    Question 3)
    This is more general question that would help me understand what's going on. There is constant quality 1 pass preset in Megui. Is it better than 2-pass? What i mean is this: for example I encode some video with "unrestricted 1 pass constant quality" preset and get a result which is, say, 700mb. Now I encode same video with preset "Unrestricted 2 pass HQ" and as a desired size, I choose 700mb. Will second video be of better quality? and why?
    Arguing with an idiot, make sure he isn't doing the same
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  2. Why do you want an average bitrate of 1200 kbps?
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  3. Member
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    That's a good question. Initially, I wanted to comperss the video. 1200 is chosen as a compromise for myself - that gives me satisfactory quality and pretty small size. But i've been asking the same question in doom9 forums and also reading some materia, and it seems that 1-pass quality based encode more suits for my needs, and it's faster either.
    Arguing with an idiot, make sure he isn't doing the same
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  4. Yeah, that's why I asked. I almost always use single pass quality based encoding. I don't care exactly how big the files are. For watchable files I use CRF 22. For more critical files I use CRF 18 or even 15.
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  5. Member
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    thanks for the tip.
    But there is quite some difference in bitrate destribution between 1pass crf and 2 pass modes. I can't understand why.
    I've made some test 1minute clip, first half i shoot moving trees and grass, and second half I put the camera and shoot almost static picture (only i move in the picture.)
    Here are the results in bitrate analyzer:
    First is 2 pass

    second is crf
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  6. 2-pass smooths out the peaks and valleys. CRF gives every frame whatever it takes.
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