File similarity evaluation scheme for multimedia data using partial hash information

File similarity is a numerical indicator that how many duplicated data exist in target files. With this information, we can reduce storage capacity with data deduplication scheme, further it can be exploited in the digital forensic field for finding malicious software. However, measuring file similarity between files can cause a high overhead in terms of processing time and the capacity of disk storage. For this reason, in this paper, we propose a novel file similarity evaluation algorithm called PHISA (Partial Hash Information String Algorithm). To evaluate the performance of the proposed system, we compare PHISA to well-known file similarity tools. The evaluation result shows that PHISA reduces the processing time and increases the similarity evaluation accuracy.