Based On The Characteristics Of Human Visual Structure Similarity Image Quality Evaluation

With the development of the internet and digital technology, digital image has gone deep into people's daily lives thoroughly, which has become the most important carrier of information. However, the image will always be distorted by varities of factors in real life, which will reduce the quality of the information. Therefore, the study of image quality assessment technique has a very important practical significance.Subjective evaluation is the most accurate evaluation method, but it costs too much manpower and time, and the process is too complicated to use in practice. Some traditional objective evaluation methods, such as MSE and PSNR, cann't reflect people's subjective feelings. Some methods of image quality evaluation which can simpy simulate the function of human eyes can reflect the people's subjective feelings better, but they are limited by the complexity of HVS and the unsolved problems. Zhou Wang proposed a simple and efficient method which based on the structure similarity theory, this method, too some extent, can objectively reflect people's subjective feelings.This paper through in-depth research on HVS and structure similarity theory to propose a structure similarity method based on HVS. Firstly, the original image and the target image are decomposed into sub-band images in different frequency and directions by wavelet transform, and the SSIM values of every sub-band image are calculated according to the SSIM method. And then, the sensitivity values of each sub-band image will be got by using the contrast sensitivity function curve. Finally, a comprehensive value can be obtained by weighting the SSIM values of all sub-band images. Through the simulation and analysis, the results show that the method proposed in this paper is more effective than the traditional evaluation method and the SSIM method, and it reflects the people's subjective feeling with higher accuracy.