This International Standard defines the electrical and mechanical characteristics of equipment which permit the interchangeability of 12,65 mm cassettes containing digitally recorded component video programmes. It specifies the content, format and recording method of the data blocks forming the helical records on the tape containing video, audio and associated data using the 12,65 mm (0,5 in) type D-5 cassettes. In addition, this standard specifies the content, format and recording method of the longitudinal record containing tracking information for the scanning head associated with the helical records, as well as the longitudinal cue audio and time and control code tracks. One video channel and four independent audio channels are recorded in the digital format. Each of these channels is designed to be capable of independent editing. The video channel records and reproduces a component television signal in the 525-line system with a frame frequency of 29,97 Hz (hereinafter referred to as "525/60 system") and 625-line system with a frame frequency of 25,00 Hz (hereinafter referred to as "625/50 system").