Color transfer has always attracted much attention in the field of image processing, but the traditional color transfer methods often have problems such as insufficient detail retention, lack of layering, and poor visual effects. To solve the above problems, this paper proposes a new method of local color transfer combining image signature and optimal transmission. Firstly, a salient region detection method based on image signature is introduced to obtain the foreground region and background region of the reference image and the content image, and then color transfer is performed in the corresponding region to improve the layering of the result image. Secondly, on the basis of the traditional linear color transfer model, combined with the optimal transmission theory, a color transfer strategy that maintains the brightness of the content image is proposed to improve the quality of the resulting image well. Finally, in order to evaluate the effect of color transfer more accurately, a new objective evaluation index of color transfer is designed in combination with chromaticity difference and structural similarity. The experimental results show that compared with the traditional color transfer method, the result image obtained by the method proposed in this paper preferably maintains the detailed information and layering of the content image, and has a more admirable visual effect (the comprehensive effect of the new method is about 30% higher than that of the traditional method). In addition, compared with the traditional color transfer evaluation index, the objective evaluation index mentioned in the article is more faithful to the users subjective evaluation result. Experimental analysis shows that compared with the traditional color transfer method, the result image obtained by the method in this paper has more outstanding performance in detail preservation, layering preservation and visual effects, and the objective evaluation index mentioned in the paper is closer to the result of subjective evaluation.