This Recommendation provides accompanying reference software for Rec. ITU-T H.264 | ISO/IEC 14496-10 as an electronic attachment. The software is an integral part of this Recommendation. The use of this reference software is not required for making an implementation of an encoder or decoder in conformance to Rec. ITU-T H.264 | ISO/IEC 14496-10. Requirements established in Rec. ITU-T H.264 | ISO/IEC 14496-10 take precedence over the behaviour of the reference software. Purpose The purpose of this Recommendation is to provide the following: ?C Reference decoder software capable of decoding bitstreams that conform to Rec. ITU-T H.264 | ISO/IEC 14496-10 in a manner that conforms to the decoding process specified in Rec. ITU-T H.264 | ISO/IEC 14496-10. ?C Reference encoder software capable of producing bitstreams that conform to Rec. ITU-T H.264 | ISO/IEC 14496-10.