640x480 for 4:3 SD video or 640x360 for 16:9 SD video in squeeze mode?

kevtim

kevtim

Active member
Hi, I have a question, it might be a silly one but here goes...

The Vimeo guidelines state that I need to upload: 640x480 for 4:3 SD video and 640x360 for 16:9 SD video

Now if I'm using squeeze mode which is it, 640x480 or 640x360 due to the fact its not true 16:9? Or is this just a ratio thing to tell Vimeo what frame the video should sit in?

Thanks
Kev
 
If you're using squeeze on an NTSC DVX, it's 720x480 with a pixel aspect ratio of 1.21.

You can export/render as 640x360, though.
 
It shouldn't. You want the export to be 16:9 using square pixels. 640 x 360 gives you that regardless of what the source footage is.

Now personally, I think Vimeo got things wrong here. The whole point of going to widescreen is to get a wider image at the same pitcure height, not an image with less picture height but the same width. If SD 4:3 is 640 x 480, then SD 16:9 really should be 854 x 480. (The image height stays the same, but it get's wider.)
 
My pal frame size is 720 x 576 in my item properties (with the anamorphic ticked obviously). Are these numbers different for NTSC? Does this frame size correspond to the 720 x 480 on vimeo?

I'm getting confused now.
 
It's confusing only because of the pixel aspect ratio.

When you export, export with square pixels (1.000), and all should be well.

However, as widescreen DV (both NTSC and PAL) is slightly wider than true 16:9, when you export, you may see slivers of black bars on the top and bottom of the frame. The only way to get rid of them is to make your timeline frame size into your export frame size and crop the footage, but it's probably not worth the effort. The bars will hardly be noticeable.
 
Why not just export at 720p, that way vimeo will recognize and retain the resolution and you don't loose any detail in your footage, at the expense of a tiny bit of aliasing. I've had really good results doing this in the past, looks way better than SD after vimeo has done its weird resolution conversions.
 
widescreen standard definition equates to 480p in square pixels. Thats 854px wide and 480px high
 
854x480 is square-pixel 16:9, but DV (and widescreen DVD-compliant MPEG-2) is wider than that. 720 x 1.21 (PAR) is 871. The 8 pixels on either side make a difference. Not an especially big difference, but enough to give slivers of black lines (unless it's cropped, or stretched vertically, which some exports/renders will do). Just saying, the black lines on the top and bottom, if you see them, are normal.

(Additionally, the square-pixel equivalent of standard-def DV is 655x480, not 640x480.)
 
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