Furthermore, the wavelength dependence of the absorption coefficient in many materials leads to a variation in the illumination spectrum reaching each segment.
The problem is challenging owing to failures arising because of variation in illumination, change in pose, size or scale, camera motion and partial or full occlusion.
The existing methods for matching of digital images, which are concerned with the comparison of the positions of directed edges, shades and mixed-range in an image with the same of another image, are often prone to error, due to noise and/or variation in illumination.
The first database contained images with no variation in illumination or pose, while the second, larger database contained images with large illumination variation and slight variations in pose.
This is mainly because these two sequences have both indoor and outdoor scenes involving significant variation in illumination.
BioID images are recorded to illustrate real world scenario such as the images have variation in illumination, different background, and various face sizes.
These conditions lead to major variation in illumination, and in this context, it is our major achievement to have a framework which successfully works in the presence of such conditions.
However, NDVI, as a ratio of two bands, is expected to correct potential errors due to topography and shade and compensate the variation in illumination resulting from terrain features [28].
We should note that we do not use the term "discounting of the illumination" to imply that observers have completely discounted the effect of variation in illumination or achieved perfect lightness constancy.
Current inactivation curtails the dynamic range of photoreceptors (e.g., when adapting to variation in illumination).
The variation in illumination did not change the temperature of the test solution, or affect the potential reported by the DISM.
