直方图是以图形化参数来显示图片曝光精确度的手段，其描述的是图片显示范围内影像的灰度分布曲线。它可以帮助分析图片的曝光水平等一些信息。-Histogram is a graphical display picture exposure parameters to measure the accuracy of its descr iption is the picture display grayscale images within the distribution curve. It can