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PubMed · 15912879

Recognizing faces defined by texture gradients.

Chang Hong Liu·Charles A Collin·Reza Farivar·Avi Chaudhuri
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Abstract

Texture gradients can reveal surface orientation in a manner similar to shape from shading, and therefore provide an important cue for object recognition. In this study, we tested whether a complex 3-D object, such as a face, can be identified from texture gradients alone. The stimuli were laser-scanned faces for which the texture element was a fractal-noise pattern mapped onto the 3-D surface. An eight-alternative forced choice task was used in which participants matched a face defined by texture gradients to one of eight faces defined by shape from shading (Experiment 1) or by texture gradients (Experiment 2). On average, participants scored 24% and 18%, respectively, above chance in these experiments. Although this performance was much poorer than the performance based entirely on shape-from-shading stimuli (Experiment 3), the results suggest that texture gradient information may be used to recover surface geometry of complex objects.

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Contrast SensitivityDepth PerceptionDiscrimination LearningFaceField Dependence-IndependenceHumansMemory, Short-TermOrientationPattern Recognition, VisualPsychophysicsTransfer, PsychologyJournal ArticleResearch Support, Non-U.S. Gov't

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Chang Hong Liu, Charles A Collin, Reza Farivar, Avi Chaudhuri. 2005. Recognizing faces defined by texture gradients.. https://doi.org/10.3758/bf03195019

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