16-bit, 44.1 kHz stereo PCM audio

Up to 74 minutes, 33 seconds

Up to 99 tracks

Up to 99 index points per track

0 is gap before track (count- down)

1 is start of audio

Minimum track length is 4 seconds 

Required 2-second gap (pre-gap) between tracks

Data disc for computer use

Up to 650 MB

DATA + AUDIO

CD Extra/CD Plus/Mixed-mode CD

Track 1 of a CD-DA contains data

Other tracks contain audio

Blue Book/Enhanced CD

Multisession disc - each session is like a complete disc, similar to hard disk partitions

First session = CD-DA (up to 98 tracks)

Second session = CD-ROM

CD players only see first session, computers see both

Preferred to CD Extra

12 cm disc

1.2 mm thick

Data on one side

Spiral track starting at center

Three miles long

1.6 microns between tracks

PIT: indentation in read surface

LAND: flat part of read surface

Pit or land = 0, transition = 1

Pit depth is 1/4 of the laser's wavelength

Land reflects laser completely

Pit reflects laser out of phase with itself

Record once

Laser burns permanent marks in dye layer

Marks prevent reflection, acting as pits

Spiral pre-groove for laser tracking

Groove wobbles for laser timing and position (ATIP)

CD-RW

Phase-change material instead of dye

Re-record up to 1,000 times

*Compatibility concerns

Blank media

Color of dye doesn't affect sound

May effect compatibility with recorder

Reflectivity

Highest index - Pressed CD

Lowest index - CD-RW

CD-R Music discs (CD-R-DA)

Required by standalone consumer CD recorders 

Data Structure

Lead-in - includes Table of Contents

Program area (a.k.a. Data)

Lead-out

Writing options

Disc-at-once (DAO)

Disc is written in one pass: Lead-in, Program, Lead-out

Writing options

Disc-at-once (DAO)

Disc is written in one pass: Lead-in, Program, Lead-out

Preferred method for one-off CD-DA and replication masters

Track-at-once (TAO)

Written track by track

Lead-in written at end

Laser stops - can be a problem for players or replicators

Session-at-once (SAO)

Entire session is written in one pass

Preferred for audio session of Blue Book

Holds up to 8 Streams of Audio

Required Formats:

PCM

Dolby Digital (AC-3)

TS_Video - DVD-Video content

TS_Audio - DVD-Audio content

Double-sided disc:

1. CD

2.DVD (DVD_A, DVD-V, or universal) 

DSD

DST - Direct Stream

Capacity = 25 GB SL or 50GB DL

Max. data transfer = 48 Mbps

PCM audio support:

6 channels @ 24/192k

8 channels @ 24/96k

16-bit, 44.1 kHz stereo PCM audio

Up to 74 minutes, 33 seconds

Up to 99 tracks

capable of 96 dB of dynamic range

Nyquist Frequency is 22.05, which is half the sample rate