中文说明： 水印是可识别图像或图案的纸出现，各种色调的亮度黑暗查看由透射光 （或反射的光，黑暗的背景之上进行查看时） 时，纸张的厚度或密度变化所造成的。[1]水印使用了一直在 请点击左侧文件开始预览 ！预览只提供20%的代码片段，完整代码需下载后查看 加载中 侵权举报 打分 发表评论 暂无评论
English Description：
A watermark is a recognizable image or pattern in paper that appears as various shades of lightness/darkness when viewed by transmitted light (or when viewed by reflected light, atop a dark background), caused by thickness or density variations in the paper. Click the file on the left to start the preview,please ！The preview only provides 20% of the code snippets, the complete code needs to be downloaded Loading Report Rate Submit No comment