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  1. I have no earthly idea how to do the resize and crop--but I suppose it is essential since my conversions are usually h264 or xvid to a dvd. So I need how to learn how to make the video 720x480... Media Info has some really small text but I think it says the AR is 2.40:1
    Also, in what order is this done? Crop, Resize and then encode? I think it's done left side, top side, right side and then bottom right? TIA
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  2. Member
    Join Date: Nov 2004
    Location: Canada
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    phuture01: I don't know if you are aware but many of today's new Blu-ray players could probably play those files if you were just to put burn these files and make a data disc or play them from a thumb drive or external hard drive. If you must make a DVD, I know that Freemake Video Converter has a way to take those files and make a basic DVD for you. I am fairly certain Video To Video Convertor has an option to convert the files to mpeg2 DVD compliant files.

    There are those who have more knowledge than me on this subject. Truthfully it is very rarely that I ever go to all the bother of making a DVD and I am rusty at it. I am sure someone will give you some pointers to get your started on this project.
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  3. Thank you sir, appreciate the response I know there are the things like convertXtodvd and the like but I guess I enjoy learning about avisynth and avstodvd--they produce high quality results--better than most of the ones I've tried. And as you say, someone might be willing to point me in the right direction--if so, then that's great.
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    Join Date: Oct 2004
    Location: New York, US
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    Last edited by sanlyn; 19th Mar 2014 at 08:48.
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  5. thank you--I think I've got the jist of it. I have a better idea of what to do now, so thanks again
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  6. Don't take what MediaInfo says as accurate. It does a lot of rounding. Most HD video uses square pixels, so the resolution and aspect ratio are the same. ie for a video with a resolution of 1280x544:
    1280/544=2.353:1

    I'd probably work it out the hard way because it's not something I'd do much. Assuming straight 16:9 resizing for NTSC DVD it'd have a display resolution of 854x480 (16:9). So to get the correct height I'd resize to a width of 854. Therefore the 1280x544 video would be resized to 854x364 (rounded). To complete the 854x480 aspect ratio, black borders need to be added top and bottom. To do so with Avisynth:
    AddBorders(0,58,0,58)
    Then the 854x480 video is resized to 720x480 and the aspect ratio set to 16:9.

    Ultimately, I'd be resizing the 1280x544 video to 720x364, using AddBorders to make it 720x480 and the aspect ratio would be 16:9.

    Having gone through all that, it was bugging me so here's the forumula. Normally when resizing video with square pixels to another size with square pixels, the formula would be:

    (original height/original width) x desired width = new height.
    ie (544/1280)x854=363

    Or to do it the other way round:
    (original width/original height) x desired height = new width.

    You can use the same formula for resizing to DVD aspect ratios, only you have to include the correct pixel aspect ratio. For straight 16:9 resizing, that's 32/27 for NTSC.

    (original height/original width) x (pixel aspect ratio) x desired width = new height.
    ie (544/1280) x (32/27) x 720 = 363

    So you'd resize to 720x364 and use add borders to give you 720x480.

    For an mpeg4 pixel aspect ratio:
    (544/1280) x (40/33) x 720 = 370

    A List of Pixel Aspect Ratios.
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  7. so i got a 1920x800 movie and if I follow your formula I came up with 720x354 and addborders(0,63,0,63)---i think
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  8. You can't use odd numbers for AddBorders, but (0,62,0,64) would work. The resizing seems right.
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  9. Thanks alot hello hello
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