fps interview – 1995

Published from 1991-2010, fps was an excellent animation magazine with an impressive cast of regular contributors.

Shortly after I left Pixar in 1992, the publisher Emru Townsend got in touch with Tony Apodaca and me for a long-running email conversation about the early days of making those computer animation things. Over the next few years, Emru, Tony and I exchanged questions and answers over a wide range of topics surrounding computer graphics and animation.

The resulting article ran on Emru’s site The Critical Eye, as well as in the print version of fps in 1995 — about 3 years after we started. I was digging through some old PDFs and found my scan of the print edition, attached here for your historical pleasure.

Sadly, Emru passed away from leukemia a few years back. His magazine was wonderful, he did some great interviews and I’m honored to have been included in that list.

pdfTownsend1995

 

Why Does the Cortex Reorganize After Sensory Loss?

meh

Investigating the Teleology of Cortical Reorganization

A growing body of evidence demonstrates that the brain can reorganize dra- matically following sensory loss. Although the existence of such neuroplastic crossmodal changes is not in doubt, the functional significance of these changes remains unclear. The dominant belief is that reorganization is com- pensatory. However, results thus far do not unequivocally indicate that sensory deprivation results in markedly enhanced abilities in other senses. Here, we consider alternative reasons besides sensory compensation that might drive the brain to reorganize after sensory loss. One such possibility is that the cortex reorganizes not to confer functional benefits, but to avoid undesirable physio- logical consequences of sensory deafferentation. Empirical assessment of the validity of this and other possibilities defines a rich program for future research.

Amy Kalia Singh, Flip Phillips, Lotfi B. Merabet, Pawan Sinha, Why Does the Cortex Reorganize after Sensory Loss?, Trends in Cognitive Sciences, Available online 12 June 2018, ISSN 1364-6613, https://doi.org/10.1016/j.tics.2018.04.004.

Keywords: cortical reorganization; plasticity; sensory loss; multimodal activations; sensory compensation

Retina and LGN

A demonstration written in Mathematica to show the interaction of the retina and LGN on the sampling of image information from the eyes.

You can play with the receptive field size to see how the whole “Hybrid Images” thing works. Click on the image to go to the demonstration.

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Citation: Flip Phillips, “Retina and LGN: Early Vision Using Gaussian Filters”,
http://demonstrations.wolfram.com/RetinaAndLGNEarlyVisionUsingGaussianFilters/
Wolfram Demonstrations Project, Published: December 22, 2017.

 

VSS 2018 – Shape scission: causal segmentation of shape

Warts, cracks, causal shape segmentation.

Research on shape perception usually focuses on the estimation of local surface geometry through cues like stereopsis, shading, or texture. Here, we argue that observers use these shape estimates to infer other object properties such as material composition and the transformation processes that generated the observed shape from this matter. We call this separation of object shape into intrinsic and extrinsic object properties shape scission. We investigated shape scission in a series of experiments with different groups of participants responding to a set of 8 unfamiliar rendered objects, each transformed by 8 transformations (e.g., “melted”, “cut”, or “inflated”). Importantly, participants could never directly compare the transformed and untransformed versions of objects. First, participants produced adjectives in a free naming task to describe what happened to the transformed objects. Second, other participants classified the objects according to either (1) their original shape, or (2) the transformation that had been applied to them. Third, participants marked those regions of the objects that were transformed away from the original shape. Finally, participants viewed objects at 5 different levels of transformation magnitude and provided perceptual ratings of deformation. We find that participants (i) are consistent in naming the transformations, (ii) can classify unfamiliar objects according to their original shape as well as the applied transformation, (iii) can identify regions of the objects that were transformed, and (iv) can to some extent perceive the magnitude of the transformation (when compared to objective mesh deformations). Thus, we can identify “objects” across transformations and “transformations” across objects, separating observed features by their causal origin (shape scission).This perceptual understanding of causal processes allows us to infer not only how objects have been altered by forces in their past but also what other members of the same class might look like.

pdfSchmidt, Phillips & Fleming 2018

VSS 2018 – Gravity and Ground Plane Geometry in Perspective Images

“The small things float to the top of… gravity” — Rickie Lee Jones

Renaissance artists noticed that placing objects on a visible ground plane anchors them stably, making it easy to perceive their depth. Subsequently, they developed methods for geometric calculation of perspective by drawing construction lines defining the ground plane. Thus, the artist constructs the geometry of pictorial space, based on the station point and the view direction, then places objects in it. This practice created a scale for placing and sizing objects on a minimally patterned ground plane.

In such paintings, feet are usually visible; our pilot experiment shows that the feet provide the viewer with an accurate perception of relative depth, configuring the scene elements into clusters. The underlying cause lies in the structure of vision, which privileges the horizontal ground and downward gravity.

pdfFourquetPhillips 2018

VSS 2018 – Exploring the Uncanny Valley

Balls! Bouncing balls. This is science so we gotta start somewhere.

Mori’s Uncanny Valley phenomena isn’t limited to robotics. It has been observed in many other areas, including the fine arts, especially photorealistic painting, sculpture, computer graphics, and animation. Furthermore, heuristic practices in the arts, especially those of traditional animation, have much to offer to our understanding of the appearance of phenomenological reality. One interesting example is the use of exaggeration to mitigate un- canny valley phenomena in animation. Action captured from live performance is frequently exaggerated so as to appear less uncanny.

pdfPhillips, Schmidt, Noejovich and Chakalos 2018

VSS…

I’ve got strong last-minute game.

Editing my VSS stuff on the Uncanny Valley. I’ll post something here when I get back.

As usual, Illustrator is doing something strange that I cannot understand.

Screen Shot 2018-05-16 at 3.08.47 PM

Nope, not supposed to look like that, in case you were wondering.

Fechner’s Aesthetics Revisited

Isn’t it beautiful?

Gustav Fechner is widely respected as a founding father of experimental psychology and psychophysics but fewer know of his interests and work in empirical aesthetics. In the later 1800s, toward the end of his career, Fechner performed experiments to empirically evaluate the beauty of rectangles, hypothesizing that the preferred shape would closely match that of the so-called ‘golden rectangle’. His findings confirmed his suspicions, but in the intervening decades there has been significant evidence pointing away from that finding. Regardless of the results of this one study, Fechner ushered in the notion of using a metric to evaluate beauty in a psychophysical way. In this paper, we recreate the experiment using more naturalistic stimuli. We evaluate subjects’ preferences against models that use various types of object complexity as metrics. Our findings that subjects prefer either very simple or very complex objects runs contrary to the hypothesized results, but are systematic nonetheless. We conclude that there are likely to be useful measures of aesthetic preference but they are likely to be complicated by the difficulty in defining some of their constituent parts.

F. Phillips, J. F. Norman, and A. Beers, “Fechner’s Aesthetics Revisited,” Seeing and Perceiving, vol. 23, no. 3, pp. 263–271, Jul. 2010.

pdfPhillipsNormanBeers2010.pdf

Combinational Imaging: Magnetic Resonance Imaging and EEG Displayed Simultaneously

Before fMRI (Functional Magnetic Resonance Imaging) existed, I got to do this.

We were one of the first labs to do this pre ‘functional’ functional imaging. Instead of volume rendering (which I would move on to Pixar to work on with Bob Drebin, Pat Hanrahan, and Loren Carpenter) we made surfaces for everything.

Abstract: We report on a new technique to combine two technologies [magnetic resonance imaging (MRI) and topographic imaging of EEG] to produce an overlapping image of both scalp-recorded EEG and the underlying brain anatomy within a given subject. High-resolution-graphics postprocessing of these data was used to create this integrated image.

M. W. Torello, F. Phillips, W. W. Hunter Jr., and C. A. Csuri, “Combinational Imaging: Magnetic Resonance Imaging and EEG Displayed Simultaneously,” Journal of Clinical Neurophysiology, vol. 4, no. 3, pp. 274–293, Jul. 1987.

DOI: 10.1097/00004691-198707000-00007

pdf Torello et al., 1987

 

The perception of surface orientation from multiple sources of optical information

The first piece of work in did in the “Todd Lab” at OSU.

I had just come off five years at Pixar and a year back in grad school in the Architecture and Planning department. I wrote most of the code for this for making and displaying objects, the interactive ‘gauge figure’ and the like. Farley and Jim came up with the distortion method (these are notoriously Farley’s “potatoes” as compared to my “glavens”. Potato, potato), and Farley and I implemented it. I wrote the gauge figure stuff during a visit with Jan Koenderink, whose book Alvy Ray Smith recommended I look at while back @ Pixar. Crazy.

Abstract: An orientation matching task was used to evaluate observers’ sensitivity to local surface orienta- tion at designated probe points on randomly shaped 3-D objects that were optically defined by tex- ture, lambertian shading, or specular highlights, These surfaces could be stationary or in motion, and they could be viewed either monocularly or stereoscopically, in all possible combinations. It was found that the deformations of shading and/or highlights (either over time or between the two eyes’ views) produced levels of performance similar to those obtained for the optical deformations of tex- tured surfaces. These findings suggest that the human visual system utilizes a much richer array of optical information to support its perception of shape than is typically appreciated.

J. F. Norman, J. T. Todd, and F. Phillips, “The perception of surface orientation from multiple sources of optical information,” Percept Psychophys, vol. 57, no. 5, pp. 629–636, Jul. 1995.

pdfNorman, Todd & Phillips, 1995.

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