使用DCT变换对图像进行水印嵌入。有嵌入和读取水印程序，有参考图片。水印是从文件中读取，读取的水印也写入到另一个txt文件中。-DCT transform image using watermark embedding. There watermark embedding and reading program, a reference picture. The watermark is read from a file, read the watermark is also written to another txt file.