Color Science for Imaging Systems

Abstract

Artists and artisans in all eras and civilizations have produced color images for aesthetic and informational purposes. The desire to produce images that record visual experiences and to share those images with others seems intrinsic to human nature. Color is an important aspect of the visual experience. It is only natural that we attempt to understand it so that we may have control over the way we use it in drawings, paintings, photographs and electronic images.

Search by photo methodology for signature properties assessment by human observers

“…On the contrary, different types of illuminants (clear sky, overcast, target in full shade etc) among the scenes in a full trial will broaden the validity of the ranking of targets as it will cover more than one standard illuminant. Important, too, is that such an approach minimizes the risk of a reduction of a target's signature effectiveness due to an increase in contrast between target and background, induced by metamers, when switching from one illuminant to another [15,16]. From a tactical point of view, a location in shaded areas will often be preferred and such positioning of targets should also be included in a signature test.…”

“…For a visual based observer trial, as an example, changes in illumination conditions will alter the luminance contrast between target and background [15,16]. We therefore emphasize our opinion that all targets (within a certain scene) must be photographed under as identical conditions as possible.…”

“…Image quality in this context is very broad, involving physical parameters such as resolution of target and illumination conditions [15,16], but also operational relevance of the images to their non-biased appearance to the observer. In the section below, we give a short description of the steps during the image capture of test targets that we needed to run through before the observer trial was carried out.…”

Peer Reviewed: Combining Multispectral Image Information Using Color.

“…So, image coding uses different systems than color specification. The systems useful for image coding are RGB and derivatives thereof such as YCbCr (which is used for digital TV transmissions in which the color information is split into the luminance component Y and two chrominance components Cb and Cr) and hue-saturation-value (HSV) (10). What all these models have in common is that color information is encoded in a three-dimensional parameter space, but they differ significantly in the way color is mapped to the corresponding color space.…”

“…However, its use with computers is not as straightforward as the RGB system. HSV and related color models, such as hue-saturation-lightness, hue-valuechroma, and chroma-colorfulness-intensity, (10) are all nonlinear transforms of the RGB model, making calculations more complicated.…”