传统的基于分形编码的水印技术一般采用0，1码，没有实现灰度图像的嵌入。本文在研究正交化分形编码的基础上，构造出水印嵌入变换函数，提出了一种能够嵌入灰度图像的分形编码水印算法，且水印提取速度大大加快。利用正交化分形解码参数在迭代过程中的不变性，使水印直接嵌入解码参数，从而实现了灰度水印嵌入。实验结果和数据表明，水印嵌入对宿主图像分形编码质量几乎没有影响，具有可行性。与传统算法相比，本文算法在抗剪切处理、低通滤波，JPEG压缩等方面具有更好的鲁棒性。

The traditional watermarking techniques based on fractal coding is generally using 0,1 sequence as the watermark. This does not implement embedding gray image as the watermark. Based on orthogonal fractal coding, a new fast watermarking technique is proposed in this article which can embed gray images. Just because the orthogonal fractal decoding is a mean-invariant iteration,the watermark can be embedded into the fractal decoding parameters directly. Experimental results show that gray image’s embedding hardly does not have any effect on the fractal decoding image. And also, this scheme is better than the traditional techniques on being robust against many attacks such as cutting, low-passing filtering, and JPEG compression.