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  1. I have read several posts about how to set the Pixel Access Ration (PAR), but I am still very confused. Can you tell me what to do ain Selur Hybrid given the following facts:
    • My raw VHS video (HuffYuv) is 720x480
    • I want to crop to clean up the edges of the video (left:8, right:8, bottom:14)
    • I want to resize to a height of 1440
    • I want to add black borders using the Letterbox feature to add the necessary black bars on top and/or side to end up with a 1920x1440 video (4:3)

    What setting should I use for the Input PAR and Output PAR?


    Image
    [Attachment 64109 - Click to enlarge]
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  2. Input PAR: most likely 10:11 (10 wide, 11 high). Output PAR is 1:1 given the target frame size and DAR.

    Instead of letterboxing you can crop the sides to match cropped bottom edge. Considering SAR of 22:15, you can crop 15 pixels on the bottom instead of 14, and crop 22 pixels on the sides.
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  3. To be sure we speak about the same thing read [INFO] About pixel aspect ratios,...

    Input PAR: the pixel aspect ration of the source. Assuming your content is properly flagged and doesn't look distorted if you look at it in the Avisynth or Vapoursynth Preview you do not touch this value. If the preview is distorted your source isn't flagged properly and you should adjust this value.

    Output PAR: is the pixel aspect ratio of the output, usually you should stick to the typical values and not use custom output PARs since hardware players often do not support them.

    Now to your your question assuming the input PAR is correct.
    You got a source with 704x466 pixels.
    Simply resizing it to 1920x... would give you 1920x1270 (~ 1270.9090.. = 1920/704*466) pixels).
    Getting it to 1920x1440 you could simply set Leterbox to 1920x1440.
    This way you would stay with square pixel (1:1) PAR.

    Simply resizing to ...x1440 would give you 2176x1440 like your screenshot shows.
    So go get 1920 you would need to squeeze the width by a factor of 2176:1920 <> 17:15.
    So using an output PAR of 17:15 would give you 1920x1440. (no need for letterboxing)

    Any other aspect ratio will require letterboxing.

    ----
    ConsumerDV was faster


    Cu Selur

    Ps.: just noticed the resizing isn't properly updated when changing the output par, fixed it locally, so it will be okay in the next release.
    (-> adjusting the width/height up/down one and back should fix that)
    Last edited by Selur; 2nd Apr 2022 at 09:51.
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  4. Capturing Memories dellsam34's Avatar
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    After you're done cropping, just resize to 1440x1080 4:3, no aspect ratio flag needed. Just make sure when you crop you are close to a 704:480 ratio few pixels give or take are ok and the frame geometry change will be hard to notice.
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