Color and luminance information in natural scenes
Parraga, Carlos Alejandro (University of Bristol. Department of Psychology)
Brelstaff, G. (University of Bristol. Department of Psychology)
Troscianko, Tom (University of Bristol. Department of Psychology)
Moorhead, I. R. (Defence Evaluation and Research Agency (Regne Unit))

Fecha:	1998
Resumen:	The spatial filtering applied by the human visual system appears to be low pass for chromatic stimuli and band pass for luminance stimuli. Here we explore whether this observed difference in contrast sensitivity reflects a real difference in the components of chrominance and luminance in natural scenes. For this purpose a digital set of 29 hyperspectral images of natural scenes was acquired and its spatial frequency content analyzed in terms of chrominance and luminance defined according to existing models of the human cone responses and visual signal processing. The statistical 1/f amplitude spatial-frequency distribution is confirmed for a variety of chromatic conditions across the visible spectrum. Our analysis suggests that natural scenes are relatively rich in high-spatial-frequency chrominance information that does not appear to be transmitted by the human visual system. This result is unlikely to have arisen from errors in the original measurements. Several reasons may combine to explain a failure to transmit high-spatial-frequency chrominance: (a) its minor importance for primate visual tasks, (b) its removal by filtering applied to compensate for chromatic aberration of the eye's optics, and (c) a biological bottleneck blocking its transmission. In addition, we graphically compare the ratios of luminance to chrominance measured by our hyperspectral camera and those measured psychophysically over an equivalent spatial-frequency range.
Derechos:	Tots els drets reservats.
Lengua:	Anglès
Documento:	Article ; recerca ; Versió acceptada per publicar
Publicado en:	Journal of the Optical Society of America. Optics, image science, and vision, Vol. 15, Issue 3 (March 1998) , p. 563-569, ISSN 1084-7529

DOI: 10.1364/JOSAA.15.000563

Postprint 20 p, 233.6 KB

El registro aparece en las colecciones:
Artículos > Artículos de investigación
Artículos > Artículos publicados