Subjective quality of colour-television pictures impaired by random noise

Quality-grading tests have been made of the effect of random noise on 625-line NTSC-type colour-television pictures. A given example of noise can be adequately measured in terms of the signal/weighted-noise ratios using filters and weighting networks appropriate to the luminance and chrominance channels, respectively. A simple logistic-type function permits the subjective effect to be readily calculated from these measurements.