TOKYO After more than three years of labor pains, the DVD Forum has announced the establishment of a format for DVD-Audio. The Forum's Steering Committee approved the format, dubbed Version 1.0, at its meeting earlier this month and will have the DVD-Audio Format book published shortly.
DVD-Audio is the fifth DVD format to be put into place, following DVD-Video, DVD-ROM, DVD-RAM and DVD-R.
The final format includes one modification to the provisional Version 1.0 format announced in September: the addition of Dolby AC-3 encoding as the standard for video clips. The new DVD-Audio format supports sampling frequencies as high as 192 kHz and as low as 44.1 kHz, and uses 16-bit, 20-bit and 24-bit quantization bits. Version 1.0 can store 192-kHz, 24-bit, two-channel sound for 74 minutes on single-layered, single-sided disks. When standard linear PCM coding is used, 64 minutes of 192-kHz, 24-bit, two-channel sound can be stored in the single-sided, single-layer 12-cm disk.
In response to requests from content producers, the Forum's Working Group 4 (WG 4) introduced a lossless coding method last year to transmit limited-transfer-rate, high-frequency audio signals without any loss of the original musical information, enabling the storage of 74 minutes of sound at the highest frequencies.
When using the lowest frequency-CD sound (44.1 kHz, 16 bits, two channels)-one single-layer, single-sided disk can store more than 7 hours of sound.
Even though they are members of WG 4, Sony and Philips proposed a competing high-performance audio-disk format, Super Audio CD (SACD), in November of 1997. The rival format, however, has seen little development to date.
In 1997, Victor Co. of Japan Ltd. (JVC) and Matsushita Electric Industrial Co. Ltd. demonstrated prototypes of DVD-Audio players based on the provisional specifications.
Although the long-awaited format is now ready, DVD groups appear to disagree about where it should be used: in very high-end hi-fi audio products, in multifunction players, or in relatively low-end portable players.
Matsushita plans in the spring to introduce a fully compatible DVD deck that can play both DVD-Video and DVD-Audio.