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Quick Question: Aspect Ratios & Resizing

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Hello.

I am working on a video that requires me to convert 640x480 video to PAL DVD format. I was just wondering if somebody could confirm for me my suspicions that resizing to 720x576 would be stretching the video. I believe that to retain the correct aspect ratio I need to resize to 704x576 which would leave narrow black bars on the sides. Is this correct? If so, that would mean that in Premiere I would scale the height to 120% and the width to 110%, yes? If I'm way off about this please let me know.

Thanks in advance for any help.

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Assuming your 640x480 video has square pixels (a pixel aspect ratio of 1:1) then, strictly in accordance with the ITU standard (as implemented by Citizen's Aspect Ratio Calculation Tool) the output resolution should be 702x576, with 9-pixel wide borders either side.

However, this assumes that the original video was created in strict accordance with standards. Since it's likely that it wasn't, I'd take the easy option and just resize to 720x576.

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Yes, the footage has square pixels. The footage comes from a handheld digital still camera. It is from Sony's DCP range and as such features MPEG recording limited in length only by the capacity of the memory stick. Is there any way to tell if Sony's MPEG files were created in accordance with the ITU standard? If so I will resize to 702x576 - if not then I'll take the 720 road.

Thanks for the quick reply and pointing out that AR calculator.

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I thought you were dealing with an AVI ripped from DVD, downsized to 640x480.

I think it's safe to assume that the camera output at 640x480 is a true 1:1 ratio.

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Yep, true 1:1 as far as I can tell. Which means I'll want to resize to 702x576?

EDIT:
I just tried a sample resize to 702x576 and it doesn't look right. I think that it looks closer to normal at 720x576. Is that strange or is there a logical explanation?

To contact me outside the forum, for trades and such my email address is my OT.com username @gmail.com