Patent ID: 6069716
Filing Date: 2000-05-30
Classification: H04N

Abstract:
A color-image reader that optically and electronically reads a recorded color image from a recording medium, said color-image reader comprising:an image sensor that senses said recorded color image as at least a first regular series of monochromatic image-pixel signals and a second regular series of monochromatic image-pixel signals during a regular reading operation;a first optimal-exposure-period determiner that determines a first optimal exposure period with respect to said first regular series of monochromatic image-pixel signals;a second optimal-exposure-period determiner that determines a second optimal exposure period with respect to said second regular series of monochromatic image-pixel signals;a first color-correction-parameter determiner that determines a first set of color-correction parameters on the basis of a first provisional series of monochromatic image-pixel signals, which is sensed from said recorded color image by said image sensor over said first optimal exposure period determined by said first optimal-exposure-period determiner; anda second color-correction-parameter determiner that determines a second set of color-correction parameters on the basis of a second provisional series of monochromatic image-pixel signals, which is sensed from said recorded color image by said image sensor over said second optimal exposure period determined by said second optimal-exposure-period determiner,wherein said first regular series of monochromatic image-pixel signals is processed by said first set of color-correction parameters such that a first regular histogram, which is produced on the basis of said first regular series of monochromatic image-pixel signals, is generated over a first predetermined level-value range, and said second regular series of monochromatic image-pixel signals is processed by said second set of color-correction parameters such that a second regular histogram, which is produced on the basis of said second regular series of monochromatic image-pixel signals, is generated over a second predetermined level-value range.