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  1. Member
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    So I got this video file and it is a Blu-ray rip to .mkv 1920x1080 (Handbrake reports 1088)
    Anyway. The aspect ratio is way wrong. I can see it. Using VLC, I change aspect ratio to 16:10 and it appears to correct it.
    Here is the deal. In order to have correct resolution it has to be set to 1920x1200 which Handbrake wont do.
    So what I did was re-size down to 1280x800 which looks great, but ... still down sized.

    Is there any way to correct this bad aspect ratio and keep full resolution or do I have to go the lower resolution route ?
    Last edited by NotSoEasy; 18th May 2012 at 03:21.
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  2. Just set the DAR with MMG (part of MkvToolNix). 1920x1200 = 1.6.
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  3. Member
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    WOW! Now that was easy ! Thanks for the help.
    Now. How would I know if that is the correct number to use ? Would this be an 'eye-ball' guess or do I need to know some math as I know the film is 1:85.1
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  4. The math, using MPEG 2 (and Divx/Xvid) terminology is:

    DAR = SAR * PAR

    where DAR is the display aspect ratio (final shape of the picture), SAR the storage aspect ratio (the frame size), and PAR the pixel aspect ratio (the shape of individual pixels).

    https://forum.videohelp.com/threads/342827-Avidemux-aspect-ratio-question-%5Bfrom-newbi...=1#post2135805

    Unfortunatately, MPEG 4 part 10 decided to change the names:

    DAR = FAR * SAR

    where DAR is the display aspect ratio, FAR is frame aspect ratio, and SAR the sample (pixel) aspect ratio. The math is the same, just the names are different.

    None of that will help you with this particular video if 1.6:1 is the correct display aspect ratio. Someone has mangled it so you have to eyeball it. 1.6:1 looked about right to me. Definitely not 1.78:1.

    Note that the display aspect ratio can be specified directly (ie, display this video with a final shape of 16:9), or indirectly by the pixel aspect ratio (and tge frame size), depending on the codec and container. The latter is useful when you crop away black borders. The shape of the remaining pixels doesn't change so you can leave the pixel aspect ratio the same. That's easier than recalculating the DAR.
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  5. Member
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    Well after my VLC solution (16:10), getting help here and reading bits and pieces elsewhere, came up with the rounding of 1:67.1

    1.60
    1 (8:5, 16:10): Widescreen computer monitor ratio (for instance 1920×1200 resolution).
    Setting to 1200 in mkvtoolnix was good, but still off.

    1.66
    1 (5:3, 15:9): 35 mm Originally a flat ratio invented by Paramount Pictures, now a standard among several European countries; native Super 16 mm frame ratio. Sometimes this ratio is rounded up to 1.67:1. From the late 1980s to the early 2000s, Walt Disney Feature Animation's CAPS program animated their features in the 1.66:1 ratio (a compromise between the 1.85:1 theatrical ratio and the 1.33:1 ratio used for home video), this format is also used on the Nintendo 3DS's top screen as well.

    Rounding up to 1.67:1 would get me 1280x765 and from there at equal proportions, 1920x1152

    I took my sample and input 1152 into mkvtoolnix and it's spot on.
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  6. I was going to mention the possibility that the correct DAR was 1.66...:1 but I didn't want to complicate matters!
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  7. Member
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    Well I'm just glad there is a simple enough tool to fix it and it does it fast.
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  8. The only problem you might have with setting the AR in the MKV header is that not all players will respect it.
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  9. Member
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    Well lucky for me, just checked original and fix on my WDTV Live+ and everything is A-OK

    Thanks again for the help !
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