ESTIMATING THE GRADIENT DIRECTION OF A LUMINANCE RAMP

被引:5
作者
ERENS, RGF
KAPPERS, AML
KOENDERINK, JJ
机构
[1] Utrecht Biophysics Research Institute (UBI), University of Utrecht, 3584 CC Utrecht
关键词
SHAPE FROM SHADING; SPATIAL CONTRAST; LUMINANCE GRADIENTS; GRADIENT DIRECTION; STIMULUS SIZE;
D O I
10.1016/0042-6989(93)90029-V
中图分类号
Q189 [神经科学];
学科分类号
071006 ;
摘要
We report on the extent to which human observers are able to indicate the gradient direction of a luminance ramp. In our experiment modulation depth ranged from 1 to 64% and field sizes subtended 0.5 to 47.5-degrees of visual angle. Observers are not able to indicate the gradient direction for modulation depths below 6%. For values above this threshold, the angular standard deviation in the responses decreases proportionally with the logarithm of the modulation depth and is about 11-degrees for a modulation depth of 64%. The angular standard deviations for supra-threshold contrast are slightly increased for the field sizes of 0.5 and 47.5-degrees but are constant over a range of field sizes of 1 to 25-degrees. Thus, size invariance holds well for this range of field sizes.
引用
收藏
页码:1639 / 1643
页数:5
相关论文
共 14 条
[1]   APPLICATION OF FOURIER ANALYSIS TO VISIBILITY OF GRATINGS [J].
CAMPBELL, FW ;
ROBSON, JG .
JOURNAL OF PHYSIOLOGY-LONDON, 1968, 197 (03) :551-&
[2]  
DEVALOIS RL, 1988, OXFORD PSYCHOL SERIE, V14, P264
[3]  
GRAHAM NVS, 1989, OXFORD PSYCHOL SERIE, V16, P452
[4]   INFLUENCE OF NUMBER OF CYCLES UPON VISUAL CONTRAST THRESHOLD FOR SPATIAL SINE WAVE PATTERNS [J].
HOEKSTRA, J ;
VANDERGO.DP ;
VANDENBR.G ;
BILSEN, FA .
VISION RESEARCH, 1974, 14 (06) :365-368
[5]   SINE-WAVE GRATINGS - SCALE-INVARIANCE AND SPATIAL INTEGRATION AT SUPRATHRESHOLD CONTRAST [J].
JAMAR, JHT ;
KOENDERINK, JJ .
VISION RESEARCH, 1983, 23 (08) :805-810
[6]   SURFACE PERCEPTION IN PICTURES [J].
KOENDERINK, JJ ;
VANDOORN, AJ ;
KAPPERS, AML .
PERCEPTION & PSYCHOPHYSICS, 1992, 52 (05) :487-496
[7]   INVARIANT FEATURES OF CONTRAST DETECTION - AN EXPLANATION IN TERMS OF SELF-SIMILAR DETECTOR ARRAYS [J].
KOENDERINK, JJ ;
VANDOORN, AJ .
JOURNAL OF THE OPTICAL SOCIETY OF AMERICA, 1982, 72 (01) :83-87
[8]   PHOTOMETRIC INVARIANTS RELATED TO SOLID SHAPE [J].
KOENDERINK, JJ ;
VANDOORN, AJ .
OPTICA ACTA, 1980, 27 (07) :981-996
[9]  
KOENDERINK JJ, 1978, VISION RES, V20, P169
[10]   VISIBILITY OF CONTINUOUS LUMINANCE GRADIENTS [J].
MCCANN, JJ ;
SAVOY, RL ;
HALL, JA ;
SCARPETTI, JJ .
VISION RESEARCH, 1974, 14 (10) :917-+