Perceptual evaluation of colorized nighttime imagery

Alexander Toet, Michael J. de Jong, Maarten A. Hogervorst, Ignace T. C. Hooge, Bernice E. Rogowitz, Thrasyvoulos N. Pappas, Huib de Ridder
2014 Human Vision and Electronic Imaging XIX  
We recently presented a color transform that produces fused nighttime imagery with a realistic color appearance (Hogervorst & Toet, 2010, Information Fusion, 11-2, 69-77). To assess the practical value of this transform we performed two experiments in which we compared human scene recognition for monochrome intensified (II) and longwave infrared (IR) imagery, and color daylight (REF) and fused multispectral (CF) imagery. First we investigated the amount of detail observers can perceive in a
more » ... t time span (the gist of the scene). Participants watched brief image presentations and provided a full report of what they had seen. Our results show that REF and CF imagery yielded the highest precision and recall measures, while both II and IR imagery yielded significantly lower values. This suggests that observers have more difficulty extracting information from monochrome than from color imagery. Next, we measured eye fixations of participants who freely explored the images. Although the overall fixation behavior was similar across image modalities, the order in which certain details were fixated varied. Persons and vehicles were typically fixated first in REF, CF and IR imagery, while they were fixated later in II imagery. In some cases, color remapping II imagery and fusion with IR imagery restored the fixation order of these image details. We conclude that color remapping can yield enhanced scene perception compared to conventional monochrome nighttime imagery, and may be deployed to tune multispectral image representation such that the resulting fixation behavior resembles the fixation behavior for daylight color imagery. Downloaded From: http://proceedings.spiedigitallibrary.org/ on 03/04/2014 Terms of Use: http://spiedl.org/terms SPIE-IS&T/Vol. 9014 901412-3 Downloaded From: http://proceedings.spiedigitallibrary.org/ on 03/04/2014 Terms of Use: http://spiedl.org/terms SPIE-IS&T/Vol. 9014 901412-6 Downloaded From: http://proceedings.spiedigitallibrary.org/ on 03/04/2014 Terms of Use: http://spiedl.org/terms SPIE-IS&T/Vol. 9014 901412-12 Downloaded From: http://proceedings.spiedigitallibrary.org/ on 03/04/2014 Terms of Use: http://spiedl.org/terms
doi:10.1117/12.2042409 dblp:conf/hvei/ToetJHH14 fatcat:iro2rq66ovei7ktelp7b6dxgx4