The perception of material qualities in real-world images

One can easily tell if a sidewalk is slippery, if food is fresh, if a spoon is made of plastic or stainless steel, or if a suspicious looking mole warrants a trip to the doctor. This ability to visually identify and discriminate materials is known as material perception and little is known about it. We have measured human material judgments on a wide range of complex, real world materials. We have gathered several diverse image databases and made use of them to conduct psychophysical studies. We asked observers to classify surfaces and objects as being made of fabric, paper, plastic or other common material categories. In the first part of this thesis, we present experiments that establish that observers can make these judgments of material category reliably, quickly and in challenging conditions of rapid presentation. We find that categorization performance cannot be explained by simple, low-level cues like color or high spatial frequencies. In the second part of the thesis, we explore judgments beyond those of common material categories. Observers judged many dimensions of material appearance such as matte vs. glossy, opaque vs. translucent, rigid vs. nonrigid, soft vs. rough to touch, and even genuine vs. fake for familiar object categories like flowers, fruits and dessert. Observers were surprisingly accurate, even in 40 millisecond presentations. In the final part of this thesis, we compare the performance of state-of-art computer vision techniques with human performance on our images and tasks and find current techniques to be severely lacking.

Department dc:contributor.department

Massachusetts Institute of Technology. Dept. of Electrical Engineering and Computer Science.

Grantor dc:publisher

Massachusetts Institute of Technology

Year dc:date.issued

2009

Author dc:creator

• Sharan, Lavanya

Advisor dc:contributor.advisor

• Edward H. Adelson.

• Electrical Engineering and Computer Science.

Statement dc:rights

• M.I.T. theses are protected by copyright. They may be viewed from this source for any purpose, but reproduction or distribution in any format is prohibited without written permission. See provided URL for inquiries about permission.

Licence dc:rights.uri

• http://dspace.mit.edu/handle/1721.1/7582

Language dc:language.iso

eng

Handle dc:identifier.uri

http://hdl.handle.net/1721.1/54644

OAI identifier oai:identifier

oai:dspace.mit.edu:1721.1/54644