human visual systems and perception c. edward chow
Post on 19-Dec-2015
222 views
TRANSCRIPT
![Page 1: Human Visual Systems and Perception C. Edward Chow](https://reader033.vdocuments.net/reader033/viewer/2022052509/56649d385503460f94a117a8/html5/thumbnails/1.jpg)
Human Visual Systems and PerceptionHuman Visual Systems and PerceptionHuman Visual Systems and PerceptionHuman Visual Systems and Perception
C. Edward C. Edward ChowChowC. Edward C. Edward ChowChow
![Page 2: Human Visual Systems and Perception C. Edward Chow](https://reader033.vdocuments.net/reader033/viewer/2022052509/56649d385503460f94a117a8/html5/thumbnails/2.jpg)
mcc chow 2
Image in Human EyeImage in Human EyeImage in Human EyeImage in Human Eye
![Page 3: Human Visual Systems and Perception C. Edward Chow](https://reader033.vdocuments.net/reader033/viewer/2022052509/56649d385503460f94a117a8/html5/thumbnails/3.jpg)
mcc chow 3
Rod and Cone Cell Rod and Cone Cell DistributionDistributionRod and Cone Cell Rod and Cone Cell DistributionDistribution
![Page 4: Human Visual Systems and Perception C. Edward Chow](https://reader033.vdocuments.net/reader033/viewer/2022052509/56649d385503460f94a117a8/html5/thumbnails/4.jpg)
mcc chow 4
Contrast Illusion Contrast Illusion Contrast Illusion Contrast Illusion
![Page 5: Human Visual Systems and Perception C. Edward Chow](https://reader033.vdocuments.net/reader033/viewer/2022052509/56649d385503460f94a117a8/html5/thumbnails/5.jpg)
mcc chow 5
Demystify Illusion with Mach Bend Demystify Illusion with Mach Bend
EffectEffect Demystify Illusion with Mach Bend Demystify Illusion with Mach Bend
EffectEffect
![Page 6: Human Visual Systems and Perception C. Edward Chow](https://reader033.vdocuments.net/reader033/viewer/2022052509/56649d385503460f94a117a8/html5/thumbnails/6.jpg)
mcc chow 6
Spatial FrequenciesSpatial FrequenciesSpatial FrequenciesSpatial FrequenciesImage can be considered as Image can be considered as superposition of gratings of different superposition of gratings of different spatial frequencies (cycles/degree).spatial frequencies (cycles/degree).
Image can be considered as Image can be considered as superposition of gratings of different superposition of gratings of different spatial frequencies (cycles/degree).spatial frequencies (cycles/degree).
![Page 7: Human Visual Systems and Perception C. Edward Chow](https://reader033.vdocuments.net/reader033/viewer/2022052509/56649d385503460f94a117a8/html5/thumbnails/7.jpg)
mcc chow 7
Contrast ImpactContrast ImpactContrast ImpactContrast Impact
![Page 8: Human Visual Systems and Perception C. Edward Chow](https://reader033.vdocuments.net/reader033/viewer/2022052509/56649d385503460f94a117a8/html5/thumbnails/8.jpg)
mcc chow 8
Visual AcuityVisual AcuityVisual AcuityVisual Acuity
Visual acuity: the Visual acuity: the smallest angular smallest angular separation at separation at which the which the individual lines individual lines can be can be distinguished. distinguished.
Depend on Depend on contrast ratio and contrast ratio and keenness of your keenness of your eyes. 1.7’ is eyes. 1.7’ is normal normal assumption= assumption= 60/(2*1.7’)~18 60/(2*1.7’)~18 cycles/degreecycles/degree
Visual acuity: the Visual acuity: the smallest angular smallest angular separation at separation at which the which the individual lines individual lines can be can be distinguished. distinguished.
Depend on Depend on contrast ratio and contrast ratio and keenness of your keenness of your eyes. 1.7’ is eyes. 1.7’ is normal normal assumption= assumption= 60/(2*1.7’)~18 60/(2*1.7’)~18 cycles/degreecycles/degree
![Page 9: Human Visual Systems and Perception C. Edward Chow](https://reader033.vdocuments.net/reader033/viewer/2022052509/56649d385503460f94a117a8/html5/thumbnails/9.jpg)
mcc chow 9
Color RepresentationColor RepresentationThree-Receptor ModelThree-Receptor ModelColor RepresentationColor RepresentationThree-Receptor ModelThree-Receptor Model
![Page 10: Human Visual Systems and Perception C. Edward Chow](https://reader033.vdocuments.net/reader033/viewer/2022052509/56649d385503460f94a117a8/html5/thumbnails/10.jpg)
mcc chow 10
Perception RepresentationPerception RepresentationPerception RepresentationPerception Representation
![Page 11: Human Visual Systems and Perception C. Edward Chow](https://reader033.vdocuments.net/reader033/viewer/2022052509/56649d385503460f94a117a8/html5/thumbnails/11.jpg)
mcc chow 11
Tristimulus CurvesTristimulus CurvesTristimulus CurvesTristimulus CurvesDevise a system with simple numbers Devise a system with simple numbers to represents all colors. (How about to represents all colors. (How about all positive numbers?)all positive numbers?)
x,y,z are proportion of X primary, Y x,y,z are proportion of X primary, Y primary, Z primary (supersaturated primary, Z primary (supersaturated red, green and blue)red, green and blue)
x=X/(X+Y+Z); y=Y /(X+Y+Z); z=1-x-x=X/(X+Y+Z); y=Y /(X+Y+Z); z=1-x-yy
Devise a system with simple numbers Devise a system with simple numbers to represents all colors. (How about to represents all colors. (How about all positive numbers?)all positive numbers?)
x,y,z are proportion of X primary, Y x,y,z are proportion of X primary, Y primary, Z primary (supersaturated primary, Z primary (supersaturated red, green and blue)red, green and blue)
x=X/(X+Y+Z); y=Y /(X+Y+Z); z=1-x-x=X/(X+Y+Z); y=Y /(X+Y+Z); z=1-x-yy
![Page 12: Human Visual Systems and Perception C. Edward Chow](https://reader033.vdocuments.net/reader033/viewer/2022052509/56649d385503460f94a117a8/html5/thumbnails/12.jpg)
mcc chow 12
CIE {X,Y,Z} systemCIE {X,Y,Z} systemCIE {X,Y,Z} systemCIE {X,Y,Z} system
CIE: Commission Internationale de I’Eclairage, The CIE: Commission Internationale de I’Eclairage, The International commission on color standards)International commission on color standards)
Figure 2.17b shows the corresponding amount of Figure 2.17b shows the corresponding amount of primaries needed to match all wavelengths of primaries needed to match all wavelengths of visible spectrum.visible spectrum.
CIE: Commission Internationale de I’Eclairage, The CIE: Commission Internationale de I’Eclairage, The International commission on color standards)International commission on color standards)
Figure 2.17b shows the corresponding amount of Figure 2.17b shows the corresponding amount of primaries needed to match all wavelengths of primaries needed to match all wavelengths of visible spectrum.visible spectrum.
![Page 13: Human Visual Systems and Perception C. Edward Chow](https://reader033.vdocuments.net/reader033/viewer/2022052509/56649d385503460f94a117a8/html5/thumbnails/13.jpg)
mcc chow 13
1931 CIE Chromaticity Diagram1931 CIE Chromaticity Diagram1931 CIE Chromaticity Diagram1931 CIE Chromaticity Diagram
![Page 14: Human Visual Systems and Perception C. Edward Chow](https://reader033.vdocuments.net/reader033/viewer/2022052509/56649d385503460f94a117a8/html5/thumbnails/14.jpg)
mcc chow 14
Color Coordinate System ConversionColor Coordinate System ConversionColor Coordinate System ConversionColor Coordinate System Conversion
![Page 15: Human Visual Systems and Perception C. Edward Chow](https://reader033.vdocuments.net/reader033/viewer/2022052509/56649d385503460f94a117a8/html5/thumbnails/15.jpg)
mcc chow 15
Transformation from NTSCTransformation from NTSCTransformation from NTSCTransformation from NTSC