Highly precise estimation scheme for remote video PSNR using spread spectrum and extraction of orthogonal transform coefficients

Abstract

AbstractWith the widespread use of the digital transmission of TV signals, it is highly desirable to establish a remote monitoring scheme for video transmission quality. As a monitoring scheme for the digital video quality in the actual transmission, the reduced reference (RR) scheme is considered promising: in this scheme the feature parameters of the original picture are extracted and transmitted for comparison with the parameters in the receiver. Consequently, this paper proposes an RR‐type picture quality‐monitoring scheme which can provide highly precise remote estimation of the PSNR of the received picture. In the proposed scheme, the sent and received signals are whitened by spectrum spreading, and orthogonal transformation is applied to the results. The transform coefficients are extracted and transmitted through the monitoring link. Due to the whitening process, highly precise PSNR estimation is realized, even though only a small number of coefficients are extracted. In order to make the whitening effective, the degradation must be distributed as uniformly as possible in the transform block. In order to deal with local picture degradation due to channel error and other factors, multiplication by a PN sequence (spatial spreading) and the inverse orthogonal transform are applied in the transform domain, resulting in effective spreading and helping to improve the precision of PSNR estimation. The Walsh–Hadamard transform, which is easy to implement, is used as the orthogonal transform. By using the proposed scheme, a PSNR estimation error of approximately ±0.1 to 0.3 dB for a monitoring link rate of 40 kbit/s is obtained, which meets practical requirements for highly precise estimation. © 2006 Wiley Periodicals, Inc. Electron Comm Jpn Pt 1, 89(6): 51–62, 2006; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/ecja.20188