Overview

Digital recording may be carried out using a magnetic tape, an optical disk (CD or DVD) or a hard disk. In all cases, the analogue video and audio are sampled and compressed to form digital data bitstreams that are stored on the recording medium. Recording on optical discs was fully explained in Chapter 20. We shall therefore start with digital magnetic tape recording.

Digital video recording on a magnetic tape was launched in 1994 under the name of DV employing a tape cassette known as digital video cassette ( DVC) and its smaller form factor MiniDV. The DV specification defines both the type of compression and the tape-recording format. Though DV quickly became the standard for home and semi-professional recording, it spawned a number of variants, most notably Sony s DVCAM and Panasonic DVCPRO formats targeted at the professional end of the market. Sony s consumer Digital8 format is another variant, which is similar to DV but recorded on Hi8 tape. A high-definition version of DV has also been developed under the name of HDV. While it uses the DV and MiniDV tape form factor, it employs the full MPEG-2 compression toolkit including inter-frame compression which is not used in the standard definition DV format.

Other formats have also been introduced including the S-VHS and the D-VHS but they did not get general acceptance by the public, especially as DVD recording started to gather pace. S-VHS improves VHS s luminance resolution by boosting the frequency deviation of the luminance...