Recommendation ITU-T H.274 specifies the syntax and semantics of video usability information (VUI) parameters and supplemental enhancement information (SEI) messages for use with coded video bitstreams. The VUI parameters and SEI messages defined in this Recommendation may be conveyed within coded video bitstreams in a manner specified in a video coding specification or may be conveyed by other means as determined by the specifications for systems that make use of such coded video bitstreams. This Recommendation is particularly intended for use with coded video bitstreams as specified by Rec. ITU-T H.266 | ISO/IEC 23090-3, although it is drafted in a manner intended to be sufficiently versatile and generic that it may also be used with other types of coded video bitstreams.

This revision adds four new versatile supplemental enhancement information (VSEI) messages for coded video bitstreams, and also includes corrections and editorial improvements to various minor defects in the prior content of this Recommendation. Changes are included as modifications to the sections of text that were previously present in H.274 V2.

This Recommendation was developed collaboratively with ISO/IEC JTC 1/SC 29 and corresponds with ISO/IEC 23002 7 as technically aligned twin text.