Subjective evaluation of a NO-reference video quality Monitoring algorithm for H.264/AVC video over a noisy channel
In this paper we evaluate NORM, a NO-Reference video quality Monitoring algorithm we proposed in a previous work, for the prediction of the subjective quality of H.264/AVC video transmitted over a noisy packet-switched network. NORM produces an estimate of the mean square error distortion at the macroblock level between the noiseless and noisy sequence, without having access to the former. The output of NORM can be readily converted into a no-reference estimate of the PSNR at the sequence level. We carried out an extensive subjective evaluation campaign on CIF and 4CIF resolution sequences encoded with H.264/AVC and transmitted over a channel that drops packets at different packet loss rates, to obtain the differential mean opinion scores. Our results show that the estimated PSNR achieves good correlation with the subjective scores, very close to the ones achieved by the PSNR computed in full-reference mode, i.e. as if the noiseless sequence would be available at the decoder.