ITU-T J.144 PDF

This Recommendation provides guidelines on the selection of appropriate perceptual video quality measurement equipment for use in digital cable television applications when the full reference measurement method can be used.

The full reference measurement method can be used when the unimpaired reference video signal is readily available at the measurement point, as may be the case of measurements on individual equipment, or a chain in the laboratory, or in a closed environment such as a cable television head-end. The estimation methods are based on processing 8-bit digital component video as defined by ITU-R Rec. BT.601-5¹. The encoder can utilize various compression methods (e.g., MPEG, H.263, etc.). The models proposed in this Recommendation may be used to evaluate a codec (encoder/decoder combination) or a concatenation of various compression methods and memory storage devices. While the derivation of the objective quality estimators described in this Recommendation might have considered error impairments (e.g., bit errors, dropped packets), independent testing results are not currently available to validate the use of the estimators for systems with error impairments. The validation test material did not contain channel errors. It contained coding degradations and the compression rates were 768 kbit/s-5 Mbit/s.

NOTE – The structure and content of this Recommendation have been organized for case of use by those familiar with the original source material; as such, the usual style of ITU-T Recommendation has not been applied.

¹ This does not preclude implementation of the measurement method for one-way video systems that utilize composite video input and outputs. Specification of the conversion between composite and component domains is not part of this Recommendation. For example, SMPTE 170M specifies one method for performing this conversion for NTSC.