利用假彩色编码加强平面痕迹辨别力的研究

在刑事照相中，有必要对一些由于曝光过度或曝光不足以及其他原因造成低质量的黑白图像进行图像处理。以满足检验鉴定的要求。假彩色编码是图像处理的一种方法。将要处理的图像底片经过郎奇光栅的调制、显影、定影后得到二维的编码片。再经过白光处理系统，在零级频谱和±１ 级频谱上分别加绿色和红色的滤波器。在输出面上得到按不同灰度赋予不同颜色的图片，使原来图像暗的地方带红色，原来图像亮的地方带绿色，介于二者之间就按红绿色比例组合。通过实验证明利用假彩色编码提高平面痕迹的辨别力是可行的。

Study on strengthening plane pattern ability to differentiate by pseudo collars coding

Because of over or insurficent exposure some inferior black and white image must be processed to satisfy the examination identification in forensic photography. Pseudo collars coding is the method to process image. The plate to be processed is modulated by ronchi raster and after developing and fixing two dimensional coding photograph is made. Then it is processed by white light and the green and red filter separatly is added to grade zero and ±1 frequency spetrum. And the photograph of different colour corresponding with different fog degree is obtained on the output plane. The original dull and bright region separatly is red and green and the region between two composes according to the ratio of red to green. It is proved that this method is effective.