| 摘要 |
PROBLEM TO BE SOLVED: To provide recording images of high quality corresponding to various kinds of document by extracting density characteristics of a document and correcting the density according to the extracted density characteristics. SOLUTION: The image signal of the document which is read out by a CCD image sensor is stored in a memory 2 by plural lines and a feature data extracting circuit 3 extracts a density histogram as feature data from this stored image signal. Then the extracted density histogram is outputted to a density correction table selecting circuit 4. Then the selecting circuit 4 discriminates what kind of characteristics the document has and outputs a select signal enabling a density correction table corresponding to the characteristics of the document to be selected to a density correcting circuit 5 according to the discrimination result. The correcting circuit 5 selects the density correction table corresponding to the density characteristics according to the select signal. Then the correcting circuit 5 corrects the density of the image signal of the document outputted by the memory 2 by using the selected density correction table. |
