Date Posted: 10/23/2019

Two early papers by CS Professor Steve Marschner recently won "test of time" awards from the conferences where they were presented.

Reflecting on each award, Marschner says: “The EGRW '99 paper was about measuring light reflection from surfaces in a clever but simple way that makes every pixel in an image into a separate measurement, which speeded up the process of measuring surfaces.” He notes that “the approach was used in several papers over the following decade or so to make measurements that were used to test lots of rendering methods.” Looking to the earlier awarded research, Marschner says “the Vis '94 paper was about techniques for interpolating between samples in volume data, such as the data that comes from medical CT scans. It proposed some ways to numerically measure the advantages of different methods, but it turns out that one of the most important contributions was not these metrics at all but the input signal we made up to test them. It became known as the ‘Marschner-Lobb test volume’ and was used by many later papers to evaluate and compare their results.” The Vis conference website has a page dedicated to this latest round of awards.

Marschner wrote the Vis ’94 paper when he was an M.Arch. student in the Program of Computer Graphics, and it was the first paper he published. Marschner earned his Ph.D. in Computer Science at Cornell in 1998 with advisors Donald P. GreenbergCharles Van Loan, and Leonard Gross.

More details about the papers and the awards:

“Image-based BRDF Measurement Including Human Skin,” by Stephen R. Marschner, Stephen H. Westin, Eric P. F. Lafortune, Kenneth E. Torrance, and Donald P. Greenberg, originally presented at the 10th Eurographics Workshop on Rendering in Granada, Spain, June 1999, won the Test of Time award from the 30th Eurographics Symposium on Rendering (the new name for the same conference). The award was announced at the most recent conference in July 2019. 

Abstract: We present a new image-based process for measuring the bidirectional reflectance of homogeneous surfaces rapidly, completely, and accurately. For simple sample shapes (spheres and cylinders) the method requires only a digital camera and a stable light source. Adding a 3D scanner allows a wide class of curved near-convex objects to be measured. With measurements for a variety of materials from paints to human skin, we demonstrate the new method's ability to achieve high resolution and accuracy over a large domain of illumination and reflection directions. We verify our measurements by tests of internal consistency and by comparison against measurements made using a gonioreflectometer.

“An Evaluation of Reconstruction Filters for Volume Rendering,” by Stephen R. Marschner and Richard J. Lobb, originally presented at IEEE Visualization ’94 in Washington, D.C., October 1994, will receive the 25 year test of time award from IEEE Vis 2019 in Vancouver, on October 22, 2019. Marschner will be in person at Vis ’19 to receive the award.

Abstract: To render images from a three-dimensional array of sample values, it is necessary to interpolate between the samples. This paper is concerned with interpolation methods that are equivalent to convolving the samples with a reconstruction filter; this covers all commonly used schemes, including trilinear and cubic interpolation.

We first outline the formal basis of interpolation in three-dimensional signal processing theory. We then propose numerical metrics that can be used to measure filter characteristics that are relevant to the appearance of images generated using that filter. We apply those metrics to several previously used filters and relate the results to isosurface images of the interpolations. We show that the choice of interpolation scheme can have a dramatic effect on image quality, and we discuss the cost/benefit tradeoff inherent in choosing a filter.