Abstract: To solve the problem of heavy workload and low efficiency when filtering images of natural reserves, on the basis of analyzing the characteristics of the collected images of natural reserves, an image filtering system based on color features is designed and implemented. Images are segmented, global color features and local color features are extracted by the system, and earth mover’s distance (EMD) is adopted to match pending images with filtered images. After judging the images according to the matching results, the images without animals are removed, thus reducing workload. By filtering the images collected at several collection points in a certain natural reserve, it is verified that the system can effectively reduce about one third of the workload of manual image filtering, and results in higher work efficiency.

Key words: color features, EMD, image filtering, image matching, natural reserve