T3D Re: Cardboarding...

[Jim Crowell <crowell@xxxxxxxxxxxxxxx>]

At 11:41 AM -0700 10/6/98, William J. Carter, Ph.D. wrote:
>
>I also believe that:
>Single lens systems provide the brain with depth information in the form of
>the various sizes and orientations of the circles of confusion; not by
>triangulation based on the centroids. But, I don't know if that belongs in
>this discussion.
>

I still don't quite understand exactly what aspect of the images you're
proposing that the brain picks up on.  If the question is, can you get
stereo depth from image pairs that don't have a sharp-edged luminance
profile, then the answer is yes.

>One thing I have noticed is that there is no card boarding in a single lens
>stereo pair.
>
>Here's the question(s) I'd like to answer:
>1. Will I get card boarding with a subject, in sharp focus, which has no
>discernable surface features, regardless of it's having a z-axis dimension?
>I expect the answer is yes, but it seems this needs to be proved.

Depends on the depth information available from the boundaries.  If, for
example, the top & bottom edges of a cylinder are visible & their
disparities specify that the front surface is curved, then you'll see a
curve in the blank region.  Your brain interpolates.

-Jim C.

-------------------------------------
Jim Crowell
Caltech Division of Biology
Mail Code 216-76
1200 E. California Blvd.
Pasadena, CA 91125
mailto:jim@xxxxxxxxxxxxxxx
http://vis.caltech.edu/~jim/Home.html


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End of TECH-3D Digest 377
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