Re: Scanline Smear...

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Dan Brockway (db++at++ParadigmSim.com)
Thu, 19 Mar 1998 08:10:24 -0600

Jan Barglowski wrote:
>
> Performers:
>
> I have a task to create scanline smear, that is, imagine a video camera
> panning so quickly that by the time the bottom scanline is imaged, the
> camera's heading is not close to when the top scanline was imaged. I
> am not interested in the scanline compression/expansion that also may
> happen, just the effect between scanlines.
>
> Solutions I've thought of:
> - create a channel for each scanline and run the app at 240X (yikes!)
> - create a slightly larger image, then shift the pixels manually with
> glReadPixels() et.al.

> - create a slightly larger image, and texture map it to a quad and
> stretch the quad along diagonally opposite corners in proportion to
> the speed of the pan.

We at Paradigm use a similar technique in domes with our Non-Linear
Distortion Correction module. 60Hz can be maintained. But beware, more
than half of the 16.6ms frame will be spent copying the frame buffer to
texture memory.

Dan

  
> Has anyone done something like this before? I'd really like to have
> it run 60Hz on my iR, if possible. Convolutions are also possible,
> but I'm not that well versed to know if this is in their domain.
>
> Thanks in advance!
>
> jan
>
> --
> Jan Anthony Barglowski jan++at++chinalake.navy.mil
> Real-time Computer Graphics http://www1.ridgecrest.ca.us/~jan
> Naval Air Warfare Center, China Lake (760) 927-1057
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-- 
Dan Brockway                          voice: (972) 960-2301
Paradigm Simulation Inc.              fax:   (972) 960-2303
14900 Landmark Blvd., Suite 400       mailto:db++at++ParadigmSim.com
Dallas TX 75240                       http://www.ParadigmSim.com
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