This revision of ITU-T H.273 includes the addition of a figure to illustrate example usage, a code point for chroma sampling grid alignment indication for the 4:2:0 colour format, correction of the range of values specification for sample aspect ratio indication, correction of the equations for the ICTCP colour representation for the hybrid-log-gamma (HLG) transfer function specified in Rec. ITU-T BT.2100-2, and correction of the equations for the transfer function for the sYCC colour representation specified in IEC 61966-2-1. This Recommendation was developed jointly with ISO/IEC JTC 1, Information technology, Subcommittee SC 29, Coding of audio, picture, multimedia and hypermedia information, and Rec. ITU-T H.273 is maintained as technically aligned twin text with ISO/IEC 23091-2. The technical changes in this edition were developed in a joint collaborative team with SC 29 in technical alignment with a not-yet-published edition of ISO/IEC 23091-2.