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  1. Searching for knowledge. trodas's Avatar
    Join Date: Feb 2008
    Location: Czech Republic
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    The problem - 730MB of "highly special" porn MKV file.
    The wanted result - normal AVI file that is playable on most computers.
    The choice of tool to convert - VirtualDub. It can - with MKV input drivers - import the MKV file and w/o reencoding save it as AVI (choose direct stream copy and if the encoding format is possible with AVI, it will works... I can live with reencodding audio anyway).

    So far, so good and everything worked out well. Even I get rid of the another audio stream, so I have only one and that make the file also smaller.

    There is only one small problem. Aspect ratio does not match. The file is played when into MKV format at 720x"576" (or at least that is what it says), but the window is only 405 pixels in height (720 pixels wide are okay and unchanged). And that way the movie looks as it should.

    But when opened in VirtualDub, it does scale to the 576 pixels and the movie looks pretty bad that way.

    And this problem stays when there is no resize and the stream is saved as it is by direct stream copy.


    So my question is - is there some plugin, that change the AR in VirtualDub, w/o the need to reencode the video? I can scale it down too, but that is not the desired effect, since it require the reencode. Any suggestions?
    "It is dangerous to be right in matters on which the established authorities are wrong." - Voltaire
    ...just keep folding, just keep folding... :) my config
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  2. You can leave the video at 720x576 and specify PAL 16:9 as the pixel aspect ratio in the Xvid settings. Or resize to 720x404 (405 isn't allowed) and encode square pixel. If you've already encoded the video with Xvid/Divx you can use Mpeg4Modifier to change the AR flags.
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  3. I'm a MEGA Super Moderator Baldrick's Avatar
    Join Date: Aug 2000
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    What is the video codec in the mkv? avi with for example h264/avc is not that "normal". Better to keep it as mkv then or reconvert to xvid.

    If it's divx/xvid then use direct stream copy and use mpeg4modifier to change the display aspect ratio to 16:9 in the avi.
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  4. Member Cornucopia's Avatar
    Join Date: Oct 2001
    Location: Deep in the Heart of Texas
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    What the heck does "highly special" mean? Or have anything to do with how to adjust the file?

    Also, Vdub isn't "rescaling" the file (unless you told it to). It is only rescaling the preview image and only by what you have set in the settings (which can be adjusted by you).

    Again, this is one of those times where it makes sense to use MediaInfo to find out what's really in the file so you can know what's going on behind the scenes.

    Scott
    "When will the rhetorical questions end?!" - George Carlin
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  5. By the way, aspect ratio flags in h.264/xvid/divx streams aren't obeyed by all players. Your safest but is to reencode as square pixel.

    I just remuxed an h.264 MKV to AVI with VirtualDub and the AR flags in the h.264 data were carried over to the stream in the AVI file. So I suspect your source videos are encoded as if they square pixel and the MKV header overrides the aspect ratio. You can't really do that with AVI.
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  6. Searching for knowledge. trodas's Avatar
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    Well, thanks for all the responses, but I would like to get things done w/o reencode. Reencode is not an option, the quality is already as it is... so yes, I would like to get rid of the MKV format, but not at the cost of reencode. Even the Xvid 2 pass does not do good enought IMHO. And IIRC that is the best codec for smal videos, so...

    Cornucopia - the reason I mention it is, that I cannot get hold of the video in any usable format or get a hi-quality BD rip and reencode it with Xvid. It is simply as it is.

    GSpot did not show any info, but VirtualDub give plenty of informations:
    "It is dangerous to be right in matters on which the established authorities are wrong." - Voltaire
    ...just keep folding, just keep folding... :) my config
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  7. Member Cornucopia's Avatar
    Join Date: Oct 2001
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    Vdub does indeed give info, just not what I wanted to check on: DAR. Also, Gspot won't work on MKV's and is not recommended anyway since it hasn't been updated in a long time. That's why I specified MediaInfo!

    You can remux an MKV into an AVI when the codec is Xvid, but as mentioned, if your MKV container header was the overriding influence in deciding the DAR, you WON'T have that capability in an AVI container.

    Divorce the idea of the AR of the file - as it will be displayed upon playback - with the idea of the AR when previewing in Virtualdub. The 2 can be quite independent.

    But first, you have to figure out what you're STARTING OUT with, and then what needs to be done to END UP with what you want.

    "It is what it is" doesn't explain ANYTHING to us. What is it - smeared, garbled, blocky, noisy? Is there NO SINGLE moment in the whole clip that is not needing censoring to upload?

    Scott
    "When will the rhetorical questions end?!" - George Carlin
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  8. Originally Posted by trodas View Post
    Even the Xvid 2 pass does not do good enought IMHO. And IIRC that is the best codec for smal videos, so...
    h.264 (MPEG 4 part 10) is far better than Xvid (MPEG 4 part 2) regardless of frame size.
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