RECOMMENDATION ITU-R BT.654 - Subjective quality of television pictures in relation to the main impairments ...
1 Continuous random noise
2 Non-linear distortion
    2.1 Differential gain
    2.2 Differential phase
3 Linear distortion
    3.1 Short-time waveform distortion
    3.2 Chrominance-luminance inequalities
4 Echo