1. COLOR MEMORY MATCH UNDER DISPARATE VIEWING CONDITION SUPERVISING BY: Jon Y. Hardeberg Peter Nussbaum Marie Kaplanová Ondrej Panák The Norwegian Color Research Laboratory Faculty of Computer Science and Media Technology Gjøvik University College Gjøvik, Norway http://www.colorlab.no Department of Graphic Arts and Photophysics Faculty of Chemical Technology University of Pardubice Pardubice, Czech republic http://www.upce.cz Master Thesis Presentation 8.7.2007, Gjøvik

2. CONTENT ♦ Introduction - Color memory - Color appearance ♦ Aim ♦ Experiment ♦ Results ♦ Conclusion

3. COLOR MEMORY ♦ Color memory shift ♦ Cognitive colors ♦ Color memory experiments - Abstract cue - Memory cue ♦ Methods - Selecting - Mixing up - Deciding

4. COLOR APPEARANCE ♦ Color appearance phenomena ♦ Color appearance models – CIECAM02 ♦ Corresponding color data sets

5. AIM ♦ Color memory match under simply specified condition (varied in surround and background parameters only) ♦ How big are the differences between mixing memory color in different condition, and can be used CIECAM02 for evaluation modeled experiment? ♦ Is memory shift really not related to the conditions of memorizing (the same conditions of mixing)?

6. VARIABLES ♦ Colors ♦ Given cue ♦ Time to show ♦ Delay time to match ♦ Shape ♦ Angular subtense ♦ Number of observers ♦ Adaptation time ♦ Background ♦ Surround ♦ Illuminant

7. EXPERIMENT EXPERIMENT 1 EXPERIMENT 2

8. EXPERIMENT 1

10. EXPERIMENT 2

12. RESULTS E-1 Dim mixing in CIELAB ab planeaL plane

13. RESULTS E-1 Mean coordinatesof different mixing in CIELAB TransformedNontransformed

14. Lighntess Chro./colorful. Hue angle LABCAM

15. Lighntess Chroma Hue angle LightDark Nontransformed vs transformed Lab

16. RESULTS E-1 Mean values of mixing CIECAM E-1 memory matchE-2 simultaneous match

17. RESULTS E-2 backroundskingreenblueredyellow gray14,5313,9116,538,9512,29 black13,3913,4516,3612,6610,76 white11,8512,9115,9510,3611,95 dE LAB backroundskingreenblueredyellow gray17,7719,7333,3315,9422,45 black16,0220,0830,4520,2419,81 white14,7319,2631,5017,2620,23 dE CAM

18. dLightness dCroma dHue backroundskingreenblueredyellow gray-13,73-2,31-5,080,44-3,80 black-13,324,03-3,646,19-0,56 white-10,516,44-1,326,020,65 backroundskingreenblueredyellow gray4,73-3,4220,414,25-5,38 black1,05-2,3716,001,36-5,44 white4,213,6018,106,09-1,90 backroundskingreenblueredyellow gray-3,818,5022,061,23-2,79 black0,699,8412,23-1,195,27 white-5,599,5511,221,123,60

19. Correlation factors for Lab LCh dL-0,59940,74450,1052 dC-0,2302-0,7010,6288 dh-0,3523-0,35920,9284 Correlation factors for CAM JMh dJ-0,58940,98910,0508 dM-0,0717-0,51060,3314 dh-0,55560,11180,8426

20. CONCLUSION ♦ CIECAM02 has weightily problem with predicting especially the chroma attribute of the color seen with the black background ♦ There is no statistical proof that the background has some influence on color memory shift. There is only slight tendency to memorize the colors as lighter, when they are shown on white background ♦ The lightness shift seems to be correlated to the chroma of original color

21. FURTHER WORK ♦ More accurate technique of mixing ♦ The variation of the condition with light sources variations as well ♦ Color memory of color pairs

22. THANK YOU FOR YOUR ATTENTION