VideoStudio 8 Preview Window Size and AVI File Questions

[Danddon]

Consider the following items, using VideoStudio 8:

1. An AVI file from Ulead, with standard AVI properties:

NTSC drop frame (29.97 fps)
Microsoft AVI files
24 bits, 720 x 480, 4:3, 29.97 fps
Lower Field First
DV Video Encoder – type 2

2. An image, 640 x 480 pixels
3. An image, 720 x 480 pixels

When the AVI file is added to the storyboard of a new project, the AVI image fills the VideoStudio Preview window, suggesting that the window is 720 x 480 pixels, which is the AVI frame size (noted above).

When the 640 x 480 pixel image is added to the storyboard with “Keep Aspect Ratio” selected, it also fills the Preview window, suggesting the window size is, instead, 640 x 480 pixels.

When the 720 x 480 pixel image is added to the storyboard with “Keep Aspect Ratio” selected, there is a black border at the top and bottom of the Preview window, again suggesting the window size is actually 640 x 480 pixels.

Questions:

1. What is the VideoStudio Preview window size in pixels?
2. If the Preview window is 640 x 480, then why does an AVI file completely fill the Preview window, instead of having borders at the top and bottom, like a 720 x 480 image file?
3. Why does the AVI file properties state 4:3 (1.333 ratio), when 720 x 480 is actually 4:2.666 (1.5 ratio)?

Obviously, there appear to be some basic assumptions about AVI files that I am missing here.

The same situation described above occurs with an MPEG-2 video file, instead of AVI.

Any thoughts on the above would be appreciated.

Thanks.

[DiscCoasterPro]

Hi, I'm not sure about this but I'm just guessing the size of the preview window is much less than standard DVD size and the files are sizing up to fit. Dunno for sure ..

dcp

[Danddon]

The discrepancy noted has to do with the "non-square pixel rendering" option in the Project Properties panel.

When this option is unchecked, the Preview window functions as expected. The pixels are rendered for computer viewing, and borders appear on the AVI file.

When it is checked, the pixels are rendered in the 4:3 ratio of the intended target - the TV screen. This causes the AVI (and MPEG) file to fill the Preview window.

Thanks for all responses to my original question.