"HDV" Specifications Proposed
Tentatively named "HDV," the format would enable the capture of HD video at 720p and 1080i on DV tape. The four companies have formulated basic specifications and plan to promote the format throughout the electronics industry with the aim of having the specifications finalized by September of this year. The effort would enable high-def recording on DV and/or Mini DV cassette tape, the same types used in consumer camcorders. Industry-wide endorsement of the specification is needed because of the growing acceptance of "high-definition video in the home," according to a joint press release issued July 4.
Adapting the DV format for high-def use would allow the use of many mechanical parts already in existence, thereby reducing tooling costs and shortening time to market of new products. As envisioned by the four development partners, the HDV format "makes it easy for manufacturers to undertake the development of products that are highly compatible with the DV format." Its 720p specifications are the same as those adopted for JVC's model GR-HD1 high-definition digital video camera, introduced in March 2003.
The inclusion of both 720p and the 1080i capabilities "will enable users to record high-definition video and further disseminate the enjoyment realized of high-definition video," the announcement stated. In the proposed HDV format, both video and audio data would be compressed via MPEG encoding—video signals by MPEG2 inter-frame compression, and audio via MPEG1 Audio Layer II encoding with "48kHz/16-bit quantization sampling frequency . . . compressed to 384kbps." The HDV interface is specified as IEEE-1394 (MPEG2-TS).
The proposal is claimed to improve error correction from single-track, as specified in the DV-SD format to error correction among multiple tracks. Although the HDV proposal does not include every possible digital video format, it does include 720p (60p, 30p, 50p, 25p), and 1080i/1440 horizontal pixels (60i, 50i). Note: no 24p professional video format. The HDV proposal also includes some specifications for MPEG encoding that enable "the display of video images during special playback such as fast search or slow-motion playback," images that may differ in quality from those seen during normal playback.
The development partners believe that the great advantage of industry-wide acceptance of HDV would be near-universal compatibility for the formats that it encompasses. "This ensures the recording and playback of high-resolution video for the high-definition era," the group stated. Read the complete press release and specifications here.