Work at Carnegie Mellon University (CMU)

Research Projects

A Physical Approach to Color Image Understanding (Ph.D. thesis)

This thesis has developed an approach to color image understanding that can be used to segment and analyze surfaces with color variations due to highlights and shading. The work is based on a theory - the Dichromatic Reflection Model - which describes the color of the reflected light as a mixture of light from surface reflection (highlights) and body reflection (object color). In the past, we have shown how the dichromatic theory can be used to separate a color image into two intrinsic reflection images: an image of just the highlights, and the original image with the highlights removed. At that time, the algorithm could only be applied to hand-segmented images. This paper shows how the same reflection model can be used to include color image segmentation into the image analysis. The result is a color image understanding system, capable of generating physical descriptions of the reflection processes occurring in the scene. Such descriptions include the intrinsic reflection images, an image segmentation, and symbolic information about the object and highlight colors. This line of research can lead to physics-based image understanding methods that are both more reliable and more useful than traditional methods.

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Implementation and Performance of a Complex Vision System on a Systolic Array Machine (Area Qualifier)

Complex vision systems are usually quite slow, requiring tens of seconds or minutes of computer time for each image. As the complexity and experimental nature of the system increases, the speed is especially low, since all components of the system must be optimized if the system is to show good performance. The FIDO system, a stereo vision system for controlling a rovot vehicle, has existed for a number of years and has been implemented on a number of different computers. These computers have ranged from a DEC KL10 to the current implementation on the Warp machine, a 100 Million Floating-point Poerations Per Second (MFLOPS) systolic array machine. FIDO has shown an enormous range in speed; its ancestor took 15 minutes per step, while the Warp implementation takes less than 5 seconds per step. Moreover, while early versions of FIDO moved in slow, start-and-stop steps, FIDO now runs continuously at 100 mm/second. We review the history of the FIDO system, discuss its implementation on different computers, and concentrate on its current Warp implementation, consisting of the implementation of three algorithms (image pyramid generation, interest operator and template correlation) on 2-10 systolic cells.

Publications

1993
	G. Klinker A Physical Approach to Color Image Understanding Book published by AK Peters, Ltd., Wellesley MA, March 1993. (Based on Ph.D. thesis, Computer Science Department, Carnegie-Mellon University, May, 1988) (bib)
1990
	G. Klinker, S. Shafer, T. Kanade A Physical Approach to Color Image Understanding International Journal on Computer Vision (IJCV), 4(1), 1990, pp. 7-38. (bib)
1988
	G. Klinker, S. Shafer, T. Kanade Color Image Analysis with an Intrinsic Reflection Model International Conference on Computer Vision (ICCV), Tarpon Springs, FL, Dec. 1988, pp. 292-296. (bib)
	G. Klinker A Physical Approach to Color Image Understanding Ph.D. thesis, Computer Science Department, Carnegie-Mellon University, May, 1988 (bib)
	G. Klinker, S. Shafer, T. Kanade The Measurement of Highlights in Color Images International Journal on Computer Vision (IJCV), 2(1), 1988, pp. 7-32. (bib)
1987
	G. Klinker, S. Shafer, T. Kanade Using a Color Reflection Model to Separate Highlights from Object Color International Conference on Computer Vision (ICCV'87), London, June 1987. (See also proc. DARPA Image Understanding Workshop, CA, Feb. 1987). (bib)
	E. Clune, J.D. Crisman, G. Klinker, J.A. Webb Implementation and Performance of a Complex Vision System on a Systolic Array Machine International Conference on Frontiers in Computing, 9-11 Dec 1987. (bib)
	G. Klinker, S. Shafer, T. Kanade Measurement of Gloss from Color Images Conference on APPEARANCE of the Inter-Society Color Council (ISCC), Colonial Williamsburg, Feb 8-11, 1987. (bib)