Input & output aspect ratios

Artbot wrote on 11/4/2002, 2:23 PM
Again, I'm new to the horrors of working in NTSC, so maybe someone can answer a question for me.

How do I know what pixel aspect ratios to use for input and output. My input is in the form of stills and 3D rendered frames, no video. Output is uncompressed AVI that runs trough another codec for use in our PS2 game engine. I'm wondering what my I/O pixel aspect ratios should be. Any ideas?

Is field order important for image quality when I'm rendering from stills?

Also, if I load the rendered uncompressed movie and re-render it out to a compressed format, what do I set the output pixel aspect ratio to, since it's already been output to a particular ratio when it was first rendered uncompressed?

FYI, I am rendering out to 640 x 448, an odd video resolution, which is what our PS2 engine requires.

Any help would be much appreciated.

Thanks

Richard

Comments

SonyDennis wrote on 11/11/2002, 8:04 AM
Richard:

You can bring in about any size and pixel aspect that you want. Vegas will (by default) add black bars to the top/bottom or left/right to make it fit the project frame aspect ratio. Using addition commands (such as pan/crop, right-click, "Match Output Aspect") you can zoom in so the bars are gone, but you're clipping the other edges.

If you want no bars and no clipping, assuming NTSC, use 655x480 images (assuming pixel aspect ratio of 1.000) or a scaled multiple thereof.

If you PS2 engine image are 640x448, I'm assuming their pixel aspect ratio is 1.0, but if it is not, fix it in the media properties dialog (and perhaps save a template so that when that size is seen again, it will remember the aspect).

Source field order is unimportant for stills, unless you're using them with the "still image sequence" feature, in which case, yes, it's important, just like it is with video.

You pixel aspect ratio for a rendering would entirely depend upon what you're rendering.

Let me know if I didn't answer your question.

///d@