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  1. Hello.

    I found a strange problem.

    i have 2 videos and i have sync them correctly according to Subtract() and sony vegas.
    when i checks a few frames at the end and at fews areas with Subtract() so i see that there is no problem.
    I get a gray screen as it should be.

    But if i play the all script, so after a some part in the video, i see that it is out of sync..
    i don't get a completely gray screen..

    this is my test script:

    v1=AVISource("s_cap1.avi").Crop(12, 6, -14, -10)
    v2=AVISource("s_cap2.avi").Crop(12, 6, -14, -10)
    Subtract(v1,v2)
    DupMC(log="test_step1.txt")

    ConvertToRGB(matrix="Rec601", interlaced=true)
    i also tried to add ConvertFPS:

    v1=AVISource("s_cap1.avi").ConvertFPS(25).Crop(12, 6, -14, -10)
    v2=AVISource("s_cap2.avi").ConvertFPS(25).Crop(12, 6, -14, -10)
    Subtract(v1,v2)
    DupMC(log="test_step1.txt")

    ConvertToRGB(matrix="Rec601", interlaced=true)
    but it didn't solve the problem.
    i also tried to Replace the AVISource() to DirectShowSource() but it even made it worse..

    i don't know what to do..
    this is why the Median1 filter didn't work well for me..
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  2. when i checks a few frames at the end and at fews areas with Subtract() so i see that there is no problem.
    Maybe something is lost in the translation, but why can't this be a "normal" result ?

    This would normally indicate that some frames are mismatched in the middle . Just because you checked a few frames and they are matched at the end, doesn't necessarily mean frames are matched elsewhere such as beginning or middle

    Are you saying when go back frame by frame to the same corresponding frames that showed differences when you played the result, there is a discrepancy ?

    Directshow "worse" result is expected, because it's not frame accurate

    What kind of AVI? What compression? Were these I-frame only ?
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  3. Everything is fine if I do not play the script.

    all frames are in sync.
    I checked a group of frames without playing all the script.
    and that group was synced properly.

    But after playing the script, I checked the same group of frames and I saw that is was out of synced.
    and all the caps was out of synced after that.

    This happens only if I play the script and get to some point in the video.

    What kind of AVI? What compression? Were these I-frame only ?
    i synced the caps in sony vegas but sony vegas didn't re-compressed the cap..

    I think it's because of this ..
    But I prefer a solution without compressing again. and use sony vegas for syncing.
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  4. so s_cap1.avi and s_cap2.avi have been processed in vegas ?

    The avs script above is dealing with these processed videos exported from vegas, or original capture?

    Were these intra only ("-g 1" in ffmpeg) ?

    Note - vegas has problems with AVC (at least long GOP) when it says "no recompression" during smart rendering (cuts only editing, pass through video, no re-encoding) often cuts and frames are out of order. For example it's supposed to be able to do this with AVCHD (used to be an advertised feature, but it's taken off the page), but it doesn't work properly all the time (maybe this is why they took it off the page?). If you used intra only, it should help


    So you're seeing a difference during playing the script vs. seeking randomly in the script, correct ? How are you checking this e.g. vdub ? or some other player/software ?
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  5. so s_cap1.avi and s_cap2.avi have been processed in vegas ?
    yes. but without compressing again.

    The avs script above is dealing with these processed videos exported from vegas, or original capture?
    the script dealing with the processed videos exported from vegas.

    Were these intra only ("-g 1" in ffmpeg) ?
    this is my cmd:
    i <Input> -vcodec libx264 -g 1 -preset medium -crf 15 -c:a copy <Output>.avi

    Bottom line: so you're seeing a difference during playing the script vs. seeking randomly, correct ? How are you checking this e.g. vdub ? or some other player/software ?
    yes.
    and i have checked it by playing the script in the "MPC-HC" player and VirtualDub.
    in both players it is the same result.
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  6. I can't explain it. I don't know why.

    AVISource should be frame accurate, especially when intra is used

    You might try FFVideoSource() instead of AVISource(), and it will be a lot slower if you used FFVideoSource("video.avi", seekmode=0, threads=1) , but might be more accurate
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  7. ok. thanks!
    but it didn't solve it..
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  8. UPDATE:

    i didn't think that it will be so easy to do this in Avisynth
    I was supposed to listen to jagabo

    i did it all in Avisynth.
    this is my script:
    LastFrame = 39658
    cap1 = AVISource("cap4.avi").trim(0,LastFrame)

    AVISource("cap3.avi")
    cap2 = trim(20,19355)+trim(19357,23108)+trim(23113,LastFr ame)

    AVISource("cap2.avi")
    cap3 = Trim(48,23110)+Trim(23115,LastFrame)

    AVISource("cap5.avi")
    cap4 = Trim(26,9327)+Trim(9329,19351)+Trim(19353,21708)+T rim(21708,23107)+Trim(23112,LastFrame)

    AVISource("cap6.avi")
    cap5 = trim(7,9328)+trim(9330,19351)+trim(19353,21707)+tr im(21707,23101)+trim(23105,LastFrame)

    Subtract(cap1,cap5) # <- the test
    It's easy because Subtract and because AvsPmod..
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