| 摘要 |
PROBLEM TO BE SOLVED: To recognize the characteristic of an original with high accuracy and also to increase the processing speed of an image processor with high accuracy when the density of image signals are corrected based on a prepared density correction table. SOLUTION: The image signals, i.e., the original read data, are inputted via an input terminal 1. A density value histogram is produced by a feature data extraction circuit 3 to show the pixel number (frequency) of each image density in response to the image signals stored in a memory 2. The circuit 3 extracts the density value of the highest frequency and the rate obtained by dividing the pixel number of the said density value by the number of all pixels that produced the said histogram as the feature data which are used for recognition of the original characteristic. Based on these two feature data, the characteristics (features) of such originals as characters, photos, etc., are recognized. Then a density correction table selection circuit 4 selects a density correction table in response to the recognized original. A density correction circuit 5 corrects the density of those input image signals based on the selected density correction table and outputs the corrected image signals via an output terminal 6. |
