Nonreference Method for Estimating PSNR of MPEG-2 Coded Video by Using DCT Coefficients and Picture Energy

Abstract

Irreversible video coding like MPEG-2 may cause deterioration in picture quality depending on the properties of the source images and coding type. A monitoring technology to assess picture quality with fluctuations is needed for digital video services. We previously proposed a method to estimate the peak signal-to-noise-ratio (PSNR) of MPEG-2 coded video by using bit stream information. The method is categorized as a nonreference measurement that does not use source signals. It estimates the amount of distortion in each frame by analyzing the information in the decoded DCT coefficients. This paper describes a way to improve the accuracy of the PSNR estimation of our previous method, especially for the not coded blocks. The proposed method utilizes the temporal fluctuations of ac energy and estimates the PSNR of not-coded blocks from the inter-frame correlation of the decoded pictures. Experimental results show that the determination coefficient <i xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">R</i> <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sup> between estimated and actual PSNRs is above 0.95 for every type of picture frame.