本文描述一种利用黑白正、负片密合检测两幅图象之间微小差异的方法。由于采用假彩色增强技术,从而克服黑白正、负片密合处理时存在强直流分量致使差异信息不明显的缺点,实现了拷贝片的反差系统γ=+1,所得H-D曲线的线性区域动态范围较大。

By utilizing the black-white synthetic PN (positive-negative) photograph for detection of difference-information between two photographs, the difference-information which is always immersed in the strong do component after the processing will now be selected and appeared due to the psendo-colour enhancement. As we make y=+l for the copy from the negative photograph, a wider dynamic range of H-D curve is provided.