New method of no-reference objectively assessing JPEG image quality
Huang Jifeng · Computer Engineering and Applications Journal · 2008
According to Parseval's theorem,the MSE in the pixel domain is equivalent to the mean square quantization error in the DCT domain because DCT is a normalized orthogonal transformation.Based on this idea,a new method of no-reference objectively assessing image quality is presented.The DCT coefficients of the ac component can be approximated as a Laplacian distribution.Firstly,estimating the Laplacian parameter from the observed dequantized DCT coefficients,amplitude distributions of DCT coefficients of the source are given,the mean square quantization error in the DCT domain is obtained.Experimental results have shown,it is in good accordance with the image quality,and in accordance with the MSE in the pixel domain.