| 摘要 |
PURPOSE:To fetch image information at high speed by determining the threshold from the image data of an image pickup condition and the threshold of the image data of other image pickup conditions based on the.image data on the area in the vicinity of an overlapped part. CONSTITUTION:A mirror is scanned, an image to be fetched is divided into plural areas and the image is fetched by two sheets of optical system composed of two sheets of imager (CCD). At this time, when the imagers IA (CCD 1) and IB (CCD 2) are the overlapped image pickup part of an oblique part, the thresh level for binarization is fixed based on brightness information. Namely, when B 1 and B 2 and Y 1 and Y 2 are defined as the black level and area brightness data of the image data obtained by the imagers 1A and 1B, the difference DELTAB of a coefficient (k) and brightness is dined by k=(Y2-B2)/(Y1-B1), DELTAB=B2-B1, and the thresh old levels T1 and T2 are fixed as T2=k(T1-B1)+B 2. Because these binarizations are performed at the same time, the processing is speeded up. |
