matlab采用半色调技术对图像进行显示：用模板近似表示10个灰度级，每一个灰度级用3*3 的模板来表示，并对如下图所示的256*256的渐变图像进行半色调输出的检验。-matlab using halftoning image display: template approximated 10 gray levels, a gray level of each template used to represent the 3* 3, and the gradation of the image as shown in Figure 256* 256 halftone inspection of the output.