image processing circuit

Abstract

Abstract PURPOSE:To obtain a satisfactory color reproducibility by executing a negative/ positive inversion between a dark and a highlight point which have been determined by a cumulative frequency of a histogram. CONSTITUTION:As for the negative image data of black-and-white, a histogram is taken by luminance component, and as for the negative image data of a color, a histogram is taken by a color component. Subsequently, from a part where a cumulative frequency of the histogram is dark, the point of a fist prescribed ratio is determined as a dark point DP, and from a part where a cumulative frequency of the histogram is dark, the point of a second prescribed ratio is determined as a highlight point HP, and between the dark point DP and the highlight point HP, negative/positive inversion is executed. In such a way, a satisfactory color reproducibility can be obtained, and also, its color reproducibility becomes stable.

Inventors

• 👤 Hideaki Kawamura
• 👤 秀明 河村

Bibliographic Details