Research on image scrambling degree evaluation method

Abstract

This paper discussed the evaluation problem of image scrambling degree (ISD). Inspired by the evaluation method of image texture characteristics, three new metrics for assessing objectively the ISD were proposed. The first method utilized the performance of energy concentration of Walsh transformation (WT), which took into account the properties that a good ISD measurement method should be contented. The second method used angular second moment (ASM) of image gray level co-occurrence matrix (GLCM). The third method combined the entropy of GLCM with image texture characteristic. Experimental results show that the proposed metrics are effective to assess the ISD, which correlates well with subjective assessment. Considering the computational complexity, the first evaluation method based on WT is remarkably superior to the method based on ASM and GLCM in terms of the time cost.