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  1. I'm converting a series of videos from dvd to XVID/avi, using AutoGK to encode.

    I have auto width selected and set to 640. Since the source aspect ratio is 16x9, the resolution should be 640x360. Yet for some reason it turns out to be 640x368, and instead of being 1.78:1(16x9) its 1.74:1. Why does AutoGK do this? Anyone else notice this? Is there any way to override this? How about a way to change the aspect ratio without re-encoding the avi?

    I tried turning off auto-crop in the AutoGK hidden settings. Still resulted in 640x368 avi.
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  2. Member FulciLives's Avatar
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    Originally Posted by iThinkYouBrokeIt
    I'm converting a series of videos from dvd to XVID/avi, using AutoGK to encode.

    I have auto width selected and set to 640. Since the source aspect ratio is 16x9, the resolution should be 640x360. Yet for some reason it turns out to be 640x368, and instead of being 1.78:1(16x9) its 1.74:1. Why does AutoGK do this? Anyone else notice this? Is there any way to override this? How about a way to change the aspect ratio without re-encoding the avi?

    I tried turning off auto-crop in the AutoGK hidden settings. Still resulted in 640x368 avi.
    Set it to use ITU resize and you will get 640x352 which is better than 640x368

    The reason it will not hit 360 exactly is due to mod 16 implementation.

    - John "FulciLives" Coleman
    "The eyes are the first thing that you have to destroy ... because they have seen too many bad things" - Lucio Fulci
    EXPLORE THE FILMS OF LUCIO FULCI - THE MAESTRO OF GORE
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  3. Originally Posted by FulciLives
    Originally Posted by iThinkYouBrokeIt
    I'm converting a series of videos from dvd to XVID/avi, using AutoGK to encode.

    I have auto width selected and set to 640. Since the source aspect ratio is 16x9, the resolution should be 640x360. Yet for some reason it turns out to be 640x368, and instead of being 1.78:1(16x9) its 1.74:1. Why does AutoGK do this? Anyone else notice this? Is there any way to override this? How about a way to change the aspect ratio without re-encoding the avi?

    I tried turning off auto-crop in the AutoGK hidden settings. Still resulted in 640x368 avi.
    Set it to use ITU resize and you will get 640x352 which is better than 640x368

    The reason it will not hit 360 exactly is due to mod 16 implementation.

    - John "FulciLives" Coleman
    What is mod 16 implementation?

    And wouldnt 640x360 be the perfect resolution, since its perfectly 16:9? 640x352 is slightly less, and 640x368 is slightly more...
    asdf
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  4. Member FulciLives's Avatar
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    Originally Posted by iThinkYouBrokeIt
    Originally Posted by FulciLives
    Originally Posted by iThinkYouBrokeIt
    I'm converting a series of videos from dvd to XVID/avi, using AutoGK to encode.

    I have auto width selected and set to 640. Since the source aspect ratio is 16x9, the resolution should be 640x360. Yet for some reason it turns out to be 640x368, and instead of being 1.78:1(16x9) its 1.74:1. Why does AutoGK do this? Anyone else notice this? Is there any way to override this? How about a way to change the aspect ratio without re-encoding the avi?

    I tried turning off auto-crop in the AutoGK hidden settings. Still resulted in 640x368 avi.
    Set it to use ITU resize and you will get 640x352 which is better than 640x368

    The reason it will not hit 360 exactly is due to mod 16 implementation.

    - John "FulciLives" Coleman
    What is mod 16 implementation?

    And wouldnt 640x360 be the perfect resolution, since its perfectly 16:9? 640x352 is slightly less, and 640x368 is slightly more...
    640x352 is mod 16 ... this means the height and width are evenly divisible by 16

    640/16 = 40
    352/16 = 22

    Also ITU will give you 640x352 whereas non ITU will give you 640x368. 640x368 is mod 16 as 368/16 = 23 but 640x352 will display better on a 16x9 WS TV than 640x368 and ITU is considered to be more "proper" anyways so ... there you go.

    Why mod 16 you say? Has something to do with macroblocks and the way MPEG encoding works.

    - John "FulciLives" Coleman
    "The eyes are the first thing that you have to destroy ... because they have seen too many bad things" - Lucio Fulci
    EXPLORE THE FILMS OF LUCIO FULCI - THE MAESTRO OF GORE
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