This Recommendation provides methodologies for the assessment of picture quality including general methods of test, the grading scales and the viewing conditions. It recommends the double-stimulus impairment scale (DSIS) method and the double-stimulus continuous quality-scale (DSCQS) method as well as alternative assessment methods such as single-stimulus (SS) methods, stimulus-comparison methods, single stimulus continuous quality evaluation (SSCQE) and simultaneous double stimulus for continuous evaluation (SDSCE) method.