The bulk of this module deals with the sizes of various parts of disc sectors, and so a brief description of each is likely helpful; for more information, see the libcdio user guide, or any of the other various documentation that people have written. Depending on the accuracy required, multiple methods of encoding data onto discs were developed enabling different degrees of error detection and recovery. For ease of implementation, these check regions are spaced evenly throughout the data, effectively dividing it into blocks of sectorSize bytes. The inner structure of each block is thus:

Sector layout

Audio

As audio CDs are intended to be listened to by human ears, often in noisy environments, byte-perfect fidelity was deemed unnecessary; data fills the entire sector without leaving room for checksums or synchronization points. This structure is more technically described as "CD-DA" (Digital Audio).

|- sectorSize -|

Data (Mode 1)

The original structure described in the Yellow Book standard. Mode 1, Form 1 is notably the layout used for CD-ROMs. It would be most correct to describe these as "Mode 1" and "Mode 2" with no reference to form, but the libcdio documentation has adopted the practice below as a parallel to the XA names.

Mode 1, Form 1

|------------------------------------ sectorSize -------------------------------------|
 syncSize + headerSize + dataSize + errorDetectionSize + padSize + errorCorrectionSize
           |------------------------------- syncedSize -------------------------------|
                                   |-------------------- tailSize --------------------|

Mode 1, Form 2

|------------ sectorSize -----------|
 syncSize + headerSize + dataSizeRaw
           |------ syncedSize ------|

XA (Mode 2)

Developed as a later extension to the Mode 1, Form 2 (technically just "Mode 2") standard above to allow different data to be interleaved.

Mode 2, Form 1

|--------------------------------------- sectorSize ----------------------------------------|
 syncSize + headerSize + subheaderSize + dataSize + errorDetectionSize + errorCorrectionSize
|---------- syncHeaderSizeXa ---------|            |-------------- tailSizeXa --------------|
           |------ headerSizeXa ------|
           |---------------------------------- syncedSize ----------------------------------|
                        |--------------------------- dataSizeRaw ---------------------------|

Mode 2, Form 2

|--------------------------- sectorSize --------------------------|
 syncSize + headerSize + subheaderSize + dataSizeRawXa + padSizeXa
|---------- syncHeaderSizeXa ---------|
           |------ headerSizeXa ------|
           |--------------------- syncedSize ---------------------|
                        |-------------- dataSizeRaw --------------|
                        |----- taggedDataSizeRaw -----|

sector.h

Defines

• CDIO_CD_CHUNK_SIZE -> chunkSize
• CDIO_CD_ECC_SIZE -> errorCorrectionSize
• CDIO_CD_EDC_SIZE -> errorDetectionSize
• CDIO_CD_FRAMESIZE -> dataSize
• CDIO_CD_FRAMESIZE_RAW -> sectorSize
• CDIO_CD_FRAMESIZE_RAW0 -> dataSizeRaw
• CDIO_CD_FRAMESIZE_RAW1 -> syncedSize
• CDIO_CD_FRAMESIZE_RAWER -> sectorSizeMax
• CDIO_CD_FRAMESIZE_SUB -> framesizeSub
• CDIO_CD_FRAMES_PER_MIN -> framesPerMin
• CDIO_CD_FRAMES_PER_SEC -> framesPerSec
• CDIO_CD_HEADER_SIZE -> headerSize
• CDIO_CD_M1F1_ZERO_SIZE -> padSize
• CDIO_CD_MAX_LSN (removed; identical to maxBound :: Lsn)
• CDIO_CD_MAX_SESSIONS -> maxSessions
• CDIO_CD_MINS -> cdMins
• CDIO_CD_MIN_LSN (removed; identical to minBound :: Lsn)
• CDIO_CD_MIN_SESSION_NO -> minSessionNo
• CDIO_CD_NUM_OF_CHUNKS -> chunksPerSector
• CDIO_CD_SECS_PER_MIN -> secsPerMin
• CDIO_CD_SUBHEADER_SIZE -> subheaderSize
• CDIO_CD_SYNC_SIZE -> syncSize
• CDIO_CD_XA_HEADER -> headerSizeXa
• CDIO_CD_XA_SYNC_HEADER -> syncHeaderSizeXa
• CDIO_CD_XA_TAIL -> tailSizeXa
• CDIO_POSTGAP_SECTORS -> postgapSectors
• CDIO_PREGAP_SECTORS -> pregapSectors
• M2F2_SECTOR_SIZE -> dataSizeRawXa
• M2RAW_SECTOR_SIZE (removed; identical to dataSizeRaw)
• M2SUB_SECTOR_SIZE -> taggedDataSizeRaw
• msf_t_SIZEOF (removed; structural constant not required for Haskell)

Types

• cdio_cd_minutes_sectors (removed; most values were simple calculations on CDIO_CD_FRAMES_PER_MIN, which can be done manually)

  • CDIO_CD_MAX_SECTORS -> maxSectors

• cdio_subchannel -> SubchannelData

  • CDIO_SUBCHANNEL_SUBQ_DATA -> QChannelData

• flag_t -> Flags and Flag

  • SCMS -> SerialCopyManagement

Symbols

• CDIO_SECTOR_SYNC_HEADER -> sectorSyncHeader
• cdio_lba_to_lsn -> lbaToLsn
• cdio_lba_to_msf -> lbaToMsf
• cdio_lba_to_msf_str -> lbaToMsfStr
• cdio_lsn_to_lba -> lsnToLba
• cdio_lsn_to_msf -> lsnToMsf
• cdio_msf_to_lba -> msfToLba
• cdio_msf_to_lsn -> msfToLsn
• cdio_msf_to_str -> msfToStr

Sound.Libcdio.Read.Data

• Flag (currently removed; unused in the translated portion of the interface)
• Flags (currently removed; unused in the translated portion of the interface)
• Lba (removed; only one address format is needed, and Lsn is more widespread)
• Msf (removed; only one address format is needed, and timestamps can be confusing for non-audio data)
• SubchannelData (currently removed; unused in the translated portion of the interface)
• cdMins -> maxCdMinutes
• chunkSize (removed; unnecessary low-level detail)
• chunksPerSector (removed; unnecessary low-level detail)
• framesizeSub (removed; unnecessary low-level detail)
• lbaToLsn (removed; only Lsn is used in Sound)
• lbaToMsf (removed; only Lsn is used in Sound)
• lbaToMsfStr -> audioTimestamp
• lsnToLba (removed; only Lsn is used in Sound)
• lsnToMsf (removed; only Lsn is used in Sound)
• maxSectors -> maxSectors
• maxSessions (removed; explicit session handling not yet implemented by libcdio)
• minSessionNo (removed; explicit session handling not yet implemented by libcdio)
• msfToLba (removed; only Lsn is used in Sound)
• msfToLsn (removed; only Lsn is used in Sound)
• msfToStr (removed; only Lsn is used in Sound)
• postgapSectors -> defaultPostgapSectors
• pregapSectors -> defaultPregapSectors
• secsPerMin (removed; real-world constant)
• sectorSyncHeader (removed; unnecessary low-level detail)
• framesPerMin (removed; simple arithmatic of framesPerSec

All size constants (e.g. sectorSize) likewise removed as unnecessary.