ATIP

Absolute Time In Pre-groove

 

The ATIP data (CD information) is located in the lead-in area of recorded CD's (CD-R and CD-RW).  It is not present in commercial, stamped CD's.  It holds some or all of the following:  

ATIP & Overburning

The ATIP usually defines an exact last possible address where data can be written, and therefore limits the size of the data.  In the typical TAO (Track At Once) mode, the last possible address and the lead out area is pre-defined by ATIP - and this prevents overburning.  

Some of the newer CDR-CDRW drives support DAO (Disk At Once) mode, where the lead-out is written by the DAO algorithm.  It can customized both the size (last possible address) and the lead-out location on the CD.  This allows overburning, IF THE DRIVE TAKES ADVANTAGE OF IT (many drives support DAO but not overburn).

How ATIP sensing is used for Copy Protection

ATIP was originally designed to simply identification and parameters of CD recordable discs - but it has blossomed into yet another copy protection scheme.  ATIP info is only present on CDR/CDRW's.  CDROM drives cannot read ATIP info.  CRR/CDRW drives do read ATIP info.

When a game or application is started that requires the original CD to be inserted, it first checks to see if ATIP info is being reported.  If it is, then it assumes the disc is not the original (which would not have any ATIP), and it will refuse to play - asking you to "Insert the CD".

3 Workarounds to run a CD with ATIP sensing Protection

some CD copy utilities, such as CloneCD, have an option to "Hide the ATIP" (CloneCD has a checkbox to "Hide CD Info" - which is the ATIP).  Then when the copy is inserted, no ATIP info is reported, and the game believes it is the original CD.
you may also be able to run the game in a CDROM drive, since that will not report the ATIP (it cannot read ATIP).
you can also run a CD emulator (daemon) that mounts CD images - and images contain files only (no ATIP)

 

ATIP Details

ATIP (Absolute Time In Pre-groove) is also called pre-groove for short. Without this data/info the CD-R cannot be used by a writer, which must have that info to be able to create a copy. The ATIP contains the following info: 

The capacity of the CD-R 
The manufacturer of the CD-R 
The type of the CD-R (eg. Audio only) 
Supported writing speeds 
Absolute lead-in time 
Last possible address where data can be written 

For example - here is an output of the ATIP by Feurio :

ATIP info from disk - Read by Feurio 1.66
Recorder: LITE-ON - LTR-48125W
ATIP start of lead in: -02:32:19 (sector: -11419)
ATIP start of lead out: 79:59:74 (sector: 359999)
Manufacturer code: 97 27 56 - Mitsui Chemicals, Inc (Type: 6)
Disc subtype: Medium Type C, low Beta category (C-)
--
ATIP start of lead in: -02:33:09 (sector: -11484)
ATIP start of lead out: 79:59:74 (sector: 359999)
Manufacturer code: 97 26 66 - CMC Magnetics Corporation (Type: 6)
Disc subtype: Medium Type A, low Beta category (A-)

Since the basic read function does not need the ATIP data - only a CD-Writer can read the ATIP (ATIP is only needed when writing a CD-R). If the copied disc is inserted into a CD-R or CD-RW, and the drive reports to the game software that ATIP info is present - the game will not launch !!! A CD-ROM will launch the game because they do not read ATIP - there is no need to. But you want your copied discs to be able to be used in both CD Players and CD Burners. Therefore, the CD copy utility must be capable of hiding the ATIP - this option shows up as "Hide CD-R Info" in CloneCD.

The ATIP protection is based on this fact: when the game starts it checks if there's ATIP info present: if so then it will presume it's a CD-R disc and will not play. However a normal CD-ROM cannot read this ATIP and will of course 'say' that this data is not present: thus the copy will work...

IMPORTANT - there is no way to create a back-up that will work - unless you can hide the ATIP information !!

There's a simple explanation for this: since some time now game developers have added an ATIP check to their protection. What this check does is search for ATIP information (which contains information like available space on the media, manufacturer, etc.) on the disc once you want to play it. 

Because ATIP is information that is only present and needed on recordable or re-writeable media, the back-up will fail to work if the drive in which it is played reports back that it has found ATIP information. There are only two solutions for this problem: 

  1. Play the back-up from a normal CD-ROM or DVD-ROM sine these devices (normally) cannot read ATIP information. 
  2. Hide the media when the back-up is played from a CD or DVD-writer or any other drive that can read ATIP information

 

The Disc Identification Code

This is part of ATIP and includes both the M and T code (Manufacturer code and Type code).  In the previous example this would be the line that says:

Manufacturer code: 97 26 66 - CMC Magnetics Corporation (Type: 6)


Manufacture code (M code)

M code indicates a manufacturer of a disc.
With reading this code, CD-R writers can identify a manufacturer of a disc.

Digits are assigned to each disc manufacturers, which are digits of minute, digits of second and first digit of frame of the Lead-in Start Time in ATIP special information (referred to section 4 in chapter 4 of the Orange Book).

Those digits are used for a writer to identify a disc manufacturer.  Two codes are prepared for a manufacturer.  A disc manufacturer can use whichever code for adapting any constant linear velocity. Overlap of this code is prohibited.

Example of M code :

Manufacturer A
1st Code
97m14s30f ~ 97m14s39f
2nd Code
97m40s20f ~ 97m40s29f

Manufacturer B
1st Code
97m14s40f ~ 97m14s49f
2nd Code
97m41s20f ~ 97m41s29f

Manufacturer C
1st Code
97m15s10f ~ 97m15s19f
2nd Code
97m40s50f ~ 97m40s59f
--



Type code (T code)

T code indicates a recording characteristics of a disc.
With reading this code, CD-R writers can identify a recording characteristics of a disc.

The second digit of frame of the Lead-in Start Time in ATIP special information is assigned for each disc type.
A disc type is defined according to disc recording characteristics.
Discs are divided into the following two groups by their recording characteristics.

Second digit of frame Characteristics
0~4 : Long Strategy Type, ( e.g. Taiyo Yuden 97m 24s 01f / Mitsubishi Chemicals Corp. 97m 34s 21f)
(I3 deviation of RF of a disc which is written in Alternative media testing condition described in the chapter 2
of the Orange Book is small, when a length of the I3 write pulse is long. ex. Cyanine type media)
(0~4: free for each manufacturers)

5~9 : Short Strategy Type ( Mitsui Toatsu 97m 27s 56f)
(I3 deviation of RF of a disc which is written in Alternative media testing condition described in the chapter 2
of the Orange Book is small, when a length of the I3 write pulse is
short. ex. Phthalocyanine type media)
(5~9: free for each manufacturers)


A number (mm:ss:fx) of a tentative code is assigned according to a request from a disc manufacturer, however, in case that the number conflicts with any existing M code, a tentative code is not issued until that conflict is solved.  In a case that a manufacturer doesn't ship a disc into a market with the assigned tentative code within 6 months after its issue date, such assigned code becomes invalid and it is deleted from the tentative code list.