DVD Demystified

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DVD-AR
The DVD Audio Recording application format was still under development
at the end of 2000. It is a modified version of the DVD-Video and DVD-
Audio specs designed for real-time audio recording from analog and digital
sources. The navigation structure is taken from DVD-Video, and the presentation
structure is taken from DVD-Audio. Of course, it would be too
much to hope that the discs would be compatible with DVD-Audio or DVD-
Video players.
Incoming audio signals can be sampled and recorded at the same resolutions
as DVD-Audio (44.1, 44, 88.2, 96, 176.4, or 192 kHz and 16, 20, or 24
bits). Only one audio stream can be recorded at a time. The audio can be
stored as uncompressed PCM or in compressed formats such as Dolby Digital
and MPEG audio.
Still pictures can be recorded along with the audio as MPEG-1 or MPEG-
2 I-frames. A memory buffer as in DVD-Audio players allows a group of still
pictures to be displayed without causing interruption of the audio. Text
information (album name, track name, lyrics, and so forth) also can be
recorded, along with the audio as album text or as real-time track text, similar
to DVD-Audio.
As with DVD-VR, user-defined play lists can be created to customize
playback of the recorded audio. Segments in a play list can be added,
deleted, reordered, combined, and divided, all without changing the original
recorded audio.
DVD-SR
Chapter 6
The DVD Stream Recording application format was still under development
at the end of 2000. The general idea of DVD-SR is to provide a standardized
way to record streaming data from any source, such as a digital
satellite receiver, digital cable tuner, digital video camera, or even streaming
content from the Internet. The recorder does not “understand” the contents
of what it is recording—it does not know if it is audio, video, stock
tickers, or something else. Therefore, the recorder is incapable of directly
playing back what it has recorded. It must pass the stream on to some other
device that knows how to interpret, decode, and present the recorded content.
DVD-SR players will use IEEE 1394/FireWire to connect to other
devices that supply or play back streams of digital content. They also will
implement copy protection using CPRM and DTCP.