In this paper, for the visual image shaping of folk culture elements in city branding, the intelligent extraction technology of digital image with image pre-processing, color space conversion, and color extraction as the three core modules is proposed. In terms of image preprocessing, spatial domain filtering is used as a means to explore the two main algorithms of linear filtering and nonlinear filtering, and in the color space conversion module, the RGB color space is converted to the CIE Lab color space with the help of CIE XYZ color. The color map extraction module uses Python language to construct the color collocation relationship network using K-means and color adjacency matrix visualization. Finally, the quantitative experiment on the effect of the city brand visual image that integrates the elements of folk culture is carried out, and 65 city brand visual image samples are quantitatively analyzed, while the AMOS model is applied to test the city brand visual image.