多点分段单步校正法在接触式图像传感器扫描仪上的实现

提出了一种接触式图像传感器(CIS)扫描仪非均匀校正的新方法,能够快速高效地完成对CIS扫描仪彩色图像的非均匀校正,消除了CIS的颜色差异。采用多点分段单步法进行标定,采用现场可编程门阵列实现校正,并最终得到颜色均匀的彩色图像。对于分辨率高达1200dpi的CIS扫描仪,采集一次样板纸完成全部颜色空间的分段标定,图像传输的同时完成校正,校正过程仅耗时0.125μs。实际应用效果显示校正后R,G,B三个通道的像素误差控制在5个像素以内,相比校正前图像均匀性提升10倍左右,比传统两点法提升3倍左右,且明显改善图像颜色突变、暗淡以及随机条纹等问题。

Realization of multi-point segmented one-setp correction medthod in contact image sensor scanner

A new non-uniformity correction method used in contact image sensor (CIS) scanner is presented, and it could rapidly and efficiently accomplish non-uniformity correction of CIS scanners color image and eliminate the color difference of CIS. To obtain uniform color images, the multi-point segmented one-step method is adopted in calibration process and FPGA is used for correcting. For the resolution of CIS scanner up to 1200 dpi, pattern paper is only captured once to complete the calibration of all color space and correction is accomplished during the acquiring image process, and it takes only 0.125 microsecond. The practical application results show that the output images uniformity is about ten times promotion than that before correction and about three times than that with traditional two-point method.