red book

Tuesday, September 26, 2006

Technical details

The Red Book specifies the physical parameters and properties of the CD, the optical "stylus" parameters, deviations and error rate, modulation system and error correction, and subcode channels and graphics.
It also specifies the form of digital audio encoding (2-channel signed 16-bit PCM sampled at 44100 Hz).
Bit rate = 44100 samples/s × 16 bit/sample × 2 channels = 1411.2 kbit/s (more than 10 MB per minute)
Sample values range from -32768 to +32767.
On the disc, the data is stored in sectors of 2352 bytes each, read at 75 sectors/s. Onto this is added the overhead of EFM, CIRC, L2 ECC, and so on, but these are not typically exposed to the application reading the disc.
By comparison, the bit rate of a "1x" data CD is defined as 2048 bytes/sector × 75 sectors/s = exactly 150 KiB/s = about 8.8 MB per minute.