Restoring Cleared CD-RW Discs

Chapter 1: CD Organization

Fig. 1.1: Cross-section of a CD (a) and enlarged image of the pits on its surface (b)

Fig. 1.2: CD is similar to an old vinyl phonograph record

Fig. 1.3: Principle of writing data on a CD

Fig. 1.4: Structure of an F1 frame

Fig. 1.5: Structure of the sector header

Fig. 1.6: Hierarchy of different data structures

Fig. 1.7: Subchannel data organization

Fig. 1.8: Data format of the Q-subchannel

Fig. 1.9: Sectors of different types

Fig. 1.10: Sector format for the MODE1 mode

Fig. 1.11: Principle of using merging bits

Fig. 1.12: Form of a high-frequency signal generated as a result of reading and interpreting a sequence of pits and lands

Fig. 1.13: Demonstration of DSV calculation

Fig. 1.14: EFM sequence with catastrophic DSV

Fig. 1.15: Sector format from the point of view of the scrambler

Fig. 1.16: Scrambler flow chart

Fig. 1.17: Computation of the scrambling sequence

Fig. 1.18: Scheme of mapping sectors to frames

Fig. 1.19: Scheme of byte swapping in F1 frame

Fig. 1.20: Process of encoding bytes

Fig. 1.21: Process of decoding bytes

Fig. 1.22: Sequence of frames making up a block

Fig. 1.23: Section structure

Fig. 1.24: CD structure

Chapter 2: Power of Reed-Solomon Codes

Fig. 2.1: Codeword structure

Formula 2.1: Dividing a polynomial by a constant by means of multiplication and addition

Fig. 2.2: Structure of the simplest Reed-Solomon encoder

Fig. 2.4: Flow chart of the syndrome computation circuit

Fig. 2.5: Flow chart of the Berlekamp-Massey algorithm

Fig. 2.3: Scheme of auto-regressive spectral decoder for Reed-Solomon correcting codes

Chapter 3: Practical Advice on Urgent System Recovery

Fig. 3.1: Critical error message displayed by Windows 2000

Fig. 3.2: Critical error message displayed by Windows 98

Fig. 3.3: Reaction of Doctor Watson to a critical error

Fig. 3.4: Blue Screen Of Death (BSOD), signaling the irrecoverable system failure and providing brief information about it

Fig. 3.5: The i386kd debugger at work; despite its minimalistic interface, it is a powerful and convenient instrument, allowing you to carry out prodigious tasks by pressing a couple of shortcut keys or keyboard combinations (one of which calls up your own script)

Fig. 3.6: Windbg with loaded memory dump. Note that the debugger automatically highlights the Bug Check codes without waiting for us to instruct it to do so, and when attempting to disassemble the instruction that has caused the critical exception, the screen displays the string specifying the name of the killer driver: Module Load: W2K KILL.SYSa nice touch

Chapter 4: Interfaces for Interaction with the Hardware

Fig. 4.1: SENSE INFO format. Sense info is returned by the device in case of error

Fig. 4.2: Description of the READ CD command

Fig. 4.3: Windows NT internals

Fig. 4.4: Architecture of the Windows 98/ME Input/Output system

Fig. 4.5: The I/O Subsystem architecture in NT

Fig. 4.6: Structure of the input buffer of the DeviceIoControl function for controlling the miniport driver under Windows 9x/NT

Chapter 6: Anti-Copying Mechanisms

Fig. 6.1: Classification of protection mechanisms

Fig. 6.2: Negative length of the first track drives the standard copier crazy

Fig. 6.3: Alcohol 120% views both sessions of the protected disk. However, the disk copy obtained using it will also be unusable

Fig. 6.4: Track length is determined as the difference between the starting address of the next track and the starting address of the current track, minus the size of the Post-gap area

Fig. 6.5: First session contains two tracks, the first of which is quite normal and genuine , while the other is the fictitious track created manually

Fig. 6.6: Ahead Nero, having encountered a fictitious track in the Pre-gap area of the genuine track, becomes so confused that it cannot correctly determine the length of all tracks. The address of the second (fictitious) track is also determined incorrectly

Fig. 6.7: Ahead Nero incorrectly determined the length of the second (fictitious) track. Strangely enough, it couldnt correctly determine the length and mode of the third track, which belongs to another session

Fig. 6.8: Disc copied by Alcohol 120% is unreadable. When attempting to view its contents, the operating system displays an error message

Fig. 6.9: Information displayed by Ahead Nero when analyzing the geometry of the protected disc. A monstrous error in determining the length of the fictitious track prevents it from being copied normally

Fig. 6.10: CDRWin refuses to determine the type of the fictitious track

Fig. 6.11: The first and the second tracks have identical starting addresses and, as a result, the length of the first track turns to zero

Fig. 6.12: Track numbering starts from 2

Fig. 6.13: Protected disc containing two tracks with the number one

Fig. 6.14: Neros response to the incorrect number of the last track

Fig. 6.15: Ahead Nero incorrectly displays track numbers

Fig. 6.16: Response of Alcohol 120% to an attempt of burn the CD image with only track number zero inside the first session

Fig. 6.17: Presence of track number 0 confuses Nero with regard to the status of the last session of the disc. Nero thinks that the second session is open , although this is actually not the case

Fig. 6.18: A data track disguised as audio

Fig. 6.19: Run-in/Run-out blocks

Chapter 7: Protection Mechanisms for Preventing Playback in PC CD-ROM

Fig. 7.1: Disc displayed in this photo is protected by Cactus Shield 2.00, which currently is the most popular protection against the digital copying of audio discs

Fig. 7.2: The negative starting address of the first audio track prevents disc playback on PC CD-ROM

Chapter 9: Protection Mechanisms Based on Binding to Storage Media

Fig. 9.1: Disc with an intentionally damaged sector (a small volcano a little below the middle of the screen). Using specialized equipment allows you to burn the surface exactly in the center of the spiral track

Fig. 9.2: Read timing diagrams of the original disc (a) and its copy (b)

Fig. 9.3: Nodal profiles obtained from two runs of the same disc

Fig. 9.4: Nodal profiles of two different discs

Fig. 9.5: Measuring the angle between sectors

Fig. 9.6: CD-physical pattern detector: a unprotected disc, b disc protected by StarForce

Fig. 9.7: CD-physical pattern detector at work: a unprotected disc, b disc protected by StarForce. The program actually allows to see the pattern! Provided that we have a large sample of measurements, the measurement error will be relatively low

Fig. 9.8: The spiral track profile for IMATION (1) and TDK (2) discs

Fig. 9.9: Physical representation of the 04 B9 04 sequence