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DRTrack.h

Includes:
<stdint.h>
<AvailabilityMacros.h>

Overview

Base class for track handling

Discussion

About tracks



A DRTrack provides data to the for the burn and contains a description of the track on disc (length, block type, data format, etc). Data is provided for the burn in a real-time thread. It is up to the track to provide this data in a timely manner, otherwise a burn underrun can occur and ruin a disc.

Data Production



DRTracks do not typically store or cache the data to be written to disk, instead the data is streamed to the disc from some data producer as it's needed. This is accomplished through an object associated with the track when the track is created called the track producer. A track producer is a class you create that implements the DRTrackDataProduction informal protocol. This protocol defines all of the methods that a track object will call during a burn to obtain data.

Track Properties



A DRTrack object contains several properties which define the track for the burn. These properties are stored in an NSDictionary and are accessed through the properties and setProperties: methods.

There are several properties that are required to be present and if they are not, will cause the burn to fail. These are:



The possible values of these properties are defined in the Mt. Fuji (IFF-8090i) specification for CD/DVD devices. It's up to you to understand the possble values and meanings of each.

All other keys contained in the properties dictionary are optional and can be omitted.


Classes

DRTrack
The DRTrack class represents a track on the burned disc.

Protocols

DRTrackDataProduction
Informal protocol describing methods implemented by a track data producer.

Categories

DRTrack(PropertyConvenience)

Constants

DRAbstractFile

extern NSString* const DRAbstractFile;
Discussion

DRFile pointing to the abstract file for ISO and Joliet volumes. The file must be in the root directory.

Availability
Introduced in Mac OS X v10.2

DRApplicationIdentifier

extern NSString* const DRApplicationIdentifier;
Discussion

NSString indicating the application identifier for ISO, Joliet and UDF volumes.

Availability
Introduced in Mac OS X v10.2

DRAudioFourChannelKey

extern NSString* const DRAudioFourChannelKey;
Discussion

For CD-DA audio tracks only. This key points to a BOOL value indicating whether the track data has four channels, as opposed to the two channels of normal stereo. If this key is not present, the engine will use a default value of NO and standard two-channel stereo is assumed.

Note that while four-channel is technically allowed in the Red Book, it never caught on and is probably being replaced by SACD, so you probably shouldn't attempt to use it.

On the media, this key corresponds to bit 3 of the control field in sub-channel Q.

Availability
Introduced in Mac OS X v10.3.

DRAudioPreEmphasisKey

extern NSString* const DRAudioPreEmphasisKey;
Discussion

For CD-DA audio tracks only. This key points to a BOOL value indicating whether the track includes pre-emphasis of 50/15us. If this key is not present, the engine will use a default value of NO. On the media, this key corresponds to bit 0 of the control field in sub-channel Q.

Availability
Introduced in Mac OS X v10.3.

DRBibliographicFile

extern NSString* const DRBibliographicFile;
Discussion

DRFile pointing to the bibliographic file for ISO and Joliet volumes. The file must be in the root directory.

Availability
Introduced in Mac OS X v10.2

DRBlockSize

extern NSString* const DRBlockSize;
Discussion

NSNumber indicating the block size of the track. Currently always 2048. Do not change.

Availability
Introduced in Mac OS X v10.2

DRBlockSizeKey

extern NSString* const DRBlockSizeKey;
Discussion

NSNumber containing the size in bytes of each track block. See the Mt. Fuji (INF-8090i) specification for CD/DVD devices for possible values for this property.

Availability
Introduced in Mac OS X v10.2

DRBlockTypeKey

extern NSString* const DRBlockTypeKey;
Discussion

NSNumber containing the type of each track block. See the Mt. Fuji (INF-8090i) specification for CD/DVD devices for possible values for this property.

Availability
Introduced in Mac OS X v10.2

DRCopyrightFile

extern NSString* const DRCopyrightFile;
Discussion

DRFile pointing to the copyright file for ISO and Joliet volumes. The file must be in the root directory.

Availability
Introduced in Mac OS X v10.2

DRDataFormKey

extern NSString* const DRDataFormKey;
Discussion

NSNumber containing the data form of each block in the track. See the Mt. Fuji (INF-8090i) specification for CD/DVD devices for possible values for this property.

Availability
Introduced in Mac OS X v10.2

DRDataPreparer

extern NSString* const DRDataPreparer;
Discussion

NSString indicating the data preparer for ISO and Joliet volumes.

Availability
Introduced in Mac OS X v10.2

DRDefaultDate

extern NSString* const DRDefaultDate;
Discussion

NSDate containing the default date to use for any unspecified dates in the filesystem. The current date and time is used if unspecified.

Availability
Introduced in Mac OS X v10.2

DRDVDCopyrightInfoKey

extern NSString* const DRDVDCopyrightInfoKey;
Discussion

For DVD tracks only. NSData containing the DVD copyright info structure sent through the SEND DVD STRUCTURE command. The contents of this will be sent directly to the drive.

Availability
Introduced in Mac OS X v10.2

DRDVDTimestampKey

extern NSString* const DRDVDTimestampKey;
Discussion

For DVD tracks only. NSData containing the DVD timestamp structure sent through the SEND DVD STRUCTURE command. The contents of this will be sent directly to the drive.

Availability
Introduced in Mac OS X v10.2

DRFreeBlocksKey

extern NSString* const DRFreeBlocksKey;
Discussion

NSNumber containing the length, in blocks, which is still available in a writable track.

Availability
Introduced in Mac OS X v10.3.

DRIndexPointsKey

extern NSString* const DRIndexPointsKey;
Discussion

For CD tracks only. This key points to an NSArray of NSNumbers, indicating the index points inside the track. Each index point is specified as a number of blocks (frames) relative to the start of the track. There are 75 blocks in one second of CD audio. No more than 98 index points may be specified for a track.

Not all drives are capable of writing index points, and not all consumer CD players report or use them. If this key is present in any track and the drive cannot write index points, the burn will fail with kDRDeviceCantWriteIndexPointsErr .

Availability
Introduced in Mac OS X v10.3.

DRISOLevel

extern NSString* const DRISOLevel;
Discussion

NSNumber containing the ISO level of the ISO-9660 filesystem on the track. Currently should be 1 or 2.

Availability
Introduced in Mac OS X v10.2

DRISOMacExtensions

extern NSString* const DRISOMacExtensions;
Discussion

NSBoolean indicating whether the track should have Mac extensions.

Availability
Introduced in Mac OS X v10.2

DRISORockRidgeExtensions

extern NSString* const DRISORockRidgeExtensions;
Discussion

NSBoolean indicating whether the track should have RockRidge (POSIX) extensions.

Availability
Introduced in Mac OS X v10.2

DRMaxBurnSpeedKey

extern NSString* const DRMaxBurnSpeedKey;
Discussion

NSNumber containing the maximum burn speed at which data can be produced. The speed is represented in KB/s (1 KB = 1000 bytes). This key can only be used to limit the speed at which the burn runs.

Availability
Introduced in Mac OS X v10.2

DRNextWritableAddressKey

extern NSString* const DRNextWritableAddressKey;
Discussion

NSNumber containing the LBA of the next writable address in the track. This key is not present in closed tracks.

Availability
Introduced in Mac OS X v10.3.

DRPreGapIsRequiredKey

extern NSString* const DRPreGapIsRequiredKey;
Discussion

For CD tracks only. NSNumber indicating whether the pregap listed for the track is required. If this key is not present, the track will behave as though the key were NO.

If this key's value is set to YES and the device does not support the exact pregap length, the burn will fail with a return value of kDRDevicePregapLengthNotAvailableErr .

If this key's value is set to YES and the device does not support any of the suggested pregap length, the engine will choose an alternate pregap length.

Availability
Introduced in Mac OS X v10.5.

DRPreGapLengthKey

extern NSString* const DRPreGapLengthKey;
Discussion

For CD tracks only. NSNumber containing the length of silence or data at the beginning of the track. This defaults to 2 seconds of silence. If this key is present, the track producer will be asked for the pregap data first. If the producer implements the proper selector, then it's the responsibility of the producer to provide data for the pregap, otherwise that length of silence will be produced by Disc Recording.

Availability
Introduced in Mac OS X v10.2

DRPublisher

extern NSString* const DRPublisher;
Discussion

NSString indicating the publisher for ISO and Joliet volumes.

Availability
Introduced in Mac OS X v10.2

DRSCMSCopyrightFree

extern NSString* const DRSCMSCopyrightFree;
Discussion

One possible value for the DRSerialCopyManagementStateKey . Indicates that the track has no copying restrictions. Copies of this track should also be copyright free.

Availability
Introduced in Mac OS X v10.3.

DRSCMSCopyrightProtectedCopy

extern NSString* const DRSCMSCopyrightProtectedCopy;
Discussion

One possible value for the DRSerialCopyManagementStateKey . Indicates that the track is a first-generation copy of an original that was subject to copy protection. No further digital copying should be allowed.

Availability
Introduced in Mac OS X v10.3.

DRSCMSCopyrightProtectedOriginal

extern NSString* const DRSCMSCopyrightProtectedOriginal;
Discussion

One possible value for the DRSerialCopyManagementStateKey . Indicates that the track is an original subject to copyright protection. Digital copying of this track should be allowed, but copies should be marked with SCMS.

Availability
Introduced in Mac OS X v10.3.

DRSerialCopyManagementStateKey

extern NSString* const DRSerialCopyManagementStateKey;
Discussion

For CD tracks only. This key points to an NSString value indicating the SCMS state of the track. If this key is not present, no SCMS data is written.

Not all drives are capable of writing SCMS. If this key is present in any track and the drive cannot write SCMS, the burn will fail with kDRDeviceCantWriteSCMSErr .

Availability
Introduced in Mac OS X v10.3.

DRSessionFormatKey

extern NSString* const DRSessionFormatKey;
Discussion

NSNumber containing the session format of the track. See the Mt. Fuji (INF-8090i) specification for CD/DVD devices for possible values for this property.

Availability
Introduced in Mac OS X v10.2

DRSessionNumberKey

extern NSString* const DRSessionNumberKey;
Discussion

NSNumber containing the physical session number of a track.

Availability
Introduced in Mac OS X v10.3.

DRSubchannelDataFormKey

extern NSString* const DRSubchannelDataFormKey;
Discussion

The property whose value is the data mode of the subchannel data sent to the drive. If this key is not present, the track will default to a value of DRSubchannelDataFormNone and no subchannel information will be requested from the producer.

Subchannel data is returned from the producer in the same production method that produces normal user data. Normally a producer returns user data in chunks of DRBlockSizeKey size. When subchannel data is also produced, the producer is expected to return user data of DRBlockSizeKey in length with an additonal 96 bytes of subchannel data. Depending on the data form specified in this key, the format of this 96 bytes is either in raw or pack format. When subchannel data is requested from the producer, the DRFlagSubchannelDataRequested flag is set in the flags parameter of producePreGapForTrack:intoBuffer:length:atAddress:blockSize:ioFlags: or produceDataForTrack:intoBuffer:length:atAddress:blockSize:ioFlags: and blockSize is increased by 96 bytes.

Availability
Introduced in Mac OS X v10.5.

DRSubchannelDataFormNone

extern NSString * const DRSubchannelDataFormNone;
Discussion

A value for DRSubchannelDataFormKey indicating that the subchannel data will not be provided by the producer.

Availability
Introduced in Mac OS X v10.5.

DRSubchannelDataFormPack

extern NSString* const DRSubchannelDataFormPack;
Discussion

A value for DRSubchannelDataFormKey indicating that the producer will be asked to provide pack format subchannel data for the track. If this form is selected, the drive will perform P and Q parity calculations on each pack and interleave the packs before writing them to disc. This corresponds to a subchannel data form of 0xC0.

Availability
Introduced in Mac OS X v10.5.

DRSubchannelDataFormRaw

extern NSString* const DRSubchannelDataFormRaw;
Discussion

A value for DRSubchannelDataFormKey indicating that the producer will be asked to provide raw format subchannel data for the track. If this form is selected, the producer must have performed P and Q parity calculations for each pack and done proper interleaving of the subchannel data. The drive will fill in the P-Q subchannel information and write the R-W subchannel data as is to the disc. This corresponds to a subchannel data form of 0x40.

Availability
Introduced in Mac OS X v10.5.

DRSuppressMacSpecificFiles

extern NSString* const DRSuppressMacSpecificFiles;
Discussion

NSBoolean indicating whether the track should suppress Mac-specific files from non-HFS filesystems.

Availability
Introduced in Mac OS X v10.3.

DRSystemIdentifier

extern NSString* const DRSystemIdentifier;
Discussion

NSString indicating the system identifier for ISO and Joliet volumes.

Availability
Introduced in Mac OS X v10.2

DRTrackIsEmptyKey

extern NSString* const DRTrackIsEmptyKey;
Discussion

NSNumber containing a BOOL value and indicates whether the track is empty.

Availability
Introduced in Mac OS X v10.3.

DRTrackISRCKey

extern NSString* const DRTrackISRCKey;
Discussion

For CD-DA audio tracks only. This key points to an NSData containing exactly 12 bytes, which will be written to the disc as the International Standard Recording Code (ISRC). If this key is not present, no ISRC is written.

The use of this value should conform to the specifications of the IFPI. See http://www.ifpi.org/isrc/ for more details on the ISRC standard.

Not all drives are capable of the write modes necessary to write the ISRC. If this key is present in any track and the drive cannot write the ISRC, the burn will fail with kDRDeviceCantWriteISRCErr .

Availability
Introduced in Mac OS X v10.3.

DRTrackLengthKey

extern NSString* const DRTrackLengthKey;
Discussion

NSNumber representing the length of the track

Availability
Introduced in Mac OS X v10.2

DRTrackModeKey

extern NSString* const DRTrackModeKey;
Discussion

NSNumber containing the track mode of the track. See the Mt. Fuji (INF-8090i) specification for CD/DVD devices for possible values for this property.

Availability
Introduced in Mac OS X v10.2

DRTrackNumberKey

extern NSString* const DRTrackNumberKey;
Discussion

NSNumber containing the physical track number of a track.

Availability
Introduced in Mac OS X v10.3.

DRTrackPacketSizeKey

extern NSString* const DRTrackPacketSizeKey;
Discussion

NSNumber containing the number of blocks per packet for the disc. It will only be present if the disc contains fixed packets. This key will contain 16 for DVD media, and typically contains either 16 or 32 for CD media.

Availability
Introduced in Mac OS X v10.3.

DRTrackPacketTypeFixed

extern NSString* const DRTrackPacketTypeFixed;
Discussion

If this is the value of the DRTrackPacketTypeKey then the disc is writen with fixed sized packets. When this value is present the DRPacketSizeKey will also be present.

Availability
Introduced in Mac OS X v10.3.

DRTrackPacketTypeKey

extern NSString* const DRTrackPacketTypeKey;
Discussion

NSString indicating the kind of packets being written.

Availability
Introduced in Mac OS X v10.3.

DRTrackPacketTypeVariable

extern NSString* const DRTrackPacketTypeVariable;
Discussion

If this is the value of the DRTrackPacketTypeKey then the disc is written with sequential variable sized packets. The presence of this value indicates the lack of the DRPacketSizeKey.

Availability
Introduced in Mac OS X v10.3.

DRTrackStartAddressKey

extern NSString* const DRTrackStartAddressKey;
Discussion

NSNumber containing the LBA of the start address for the track.

Availability
Introduced in Mac OS X v10.3.

DRTrackTypeClosed

extern NSString* const DRTrackTypeClosed;
Discussion

If this is the value of the DRTrackTypeKey then the track has been written and is closed.

Availability
Introduced in Mac OS X v10.3.

DRTrackTypeIncomplete

extern NSString* const DRTrackTypeIncomplete;
Discussion

If this is the value of the DRTrackTypeKey then the track is not invisible or reserved and is available for writing.

Availability
Introduced in Mac OS X v10.3.

DRTrackTypeInvisible

extern NSString* const DRTrackTypeInvisible;
Discussion

If this is the value of the DRTrackTypeKey then the track is invisible and available to writing. If it is packet written and not closed, DRPacketTypeKey will be present, along with DRTrackPacketType and DRTrackPacketSize keys.

Availability
Introduced in Mac OS X v10.3.

DRTrackTypeKey

extern NSString* const DRTrackTypeKey;
Discussion

NSString indicating the type of track. Possible values are: DRTrackTypeInvisible , DRTrackTypeIncomplete , DRTrackTypeReserved or DRTrackTypeClosed .

Availability
Introduced in Mac OS X v10.3.

DRTrackTypeReserved

extern NSString* const DRTrackTypeReserved;
Discussion

If this is the value of the DRTrackTypeKey then the track is reserved for writing.

Availability
Introduced in Mac OS X v10.3.

DRVerificationTypeChecksum

extern NSString * const DRVerificationTypeChecksum;
Discussion

One of the possible values of the DRVerificationTypeKey . The engine will verify the track data with an internally calculated checksum.

Availability
Introduced in Mac OS X v10.4.

DRVerificationTypeKey

extern NSString* const DRVerificationTypeKey;
Discussion

NSString indicating the type of verification to be performed. If this is not present, the track will not be verified.

Availability
Introduced in Mac OS X v10.2

DRVerificationTypeNone

extern NSString* const DRVerificationTypeNone;
Discussion

One of the possible values of the DRVerificationTypeKey . No verification is desired, so verification will be skipped.

Availability
Introduced in Mac OS X v10.2

DRVerificationTypeProduceAgain

extern NSString* const DRVerificationTypeProduceAgain;
Discussion

One of the possible values of the DRVerificationTypeKey . The engine will simply begin another production cycle and start calling <produceDataForTrack:intoBuffer:length:atAddress:blockSize:ioFlags: again.

Availability
Introduced in Mac OS X v10.2

DRVerificationTypeReceiveData

extern NSString* const DRVerificationTypeReceiveData;
Discussion

One of the possible values of the DRVerificationTypeKey . The engine will begin reading data from the disc and calling verifyDataForTrack:inBuffer:length:atAddress:blockSize:ioFlags: .

Availability
Introduced in Mac OS X v10.2

DRVolumeCheckedDate

extern NSString* const DRVolumeCheckedDate;
Discussion

NSDate containing the volume-checked date for HFS+ volumes. DRDefaultDate is used if unspecified.

Availability
Introduced in Mac OS X v10.2

DRVolumeCreationDate

extern NSString* const DRVolumeCreationDate;
Discussion

NSDate containing the volume creation date. DRDefaultDate is used if unspecified.

Availability
Introduced in Mac OS X v10.2

DRVolumeEffectiveDate

extern NSString* const DRVolumeEffectiveDate;
Discussion

NSDate containing the date and time at which the volume is effective for ISO and Joliet volumes.

Availability
Introduced in Mac OS X v10.2

DRVolumeExpirationDate

extern NSString* const DRVolumeExpirationDate;
Discussion

NSDate containing the volume expiration date for ISO and Joliet volumes.

Availability
Introduced in Mac OS X v10.2

DRVolumeModificationDate

extern NSString* const DRVolumeModificationDate;
Discussion

NSDate containing the volume modification date. DRDefaultDate is used if unspecified.

Availability
Introduced in Mac OS X v10.2

DRVolumeSet

extern NSString* const DRVolumeSet;
Discussion

NSString indicating the volume set name for ISO and Joliet volumes.

Availability
Introduced in Mac OS X v10.2

Enumerations

Track Flags

#if MAC_OS_X_VERSION_MAX_ALLOWED >= MAC_OS_X_VERSION_10_5 
enum { 
    DRFlagSubchannelDataRequested = (
        1 << 1) 
};  
#endif
Constants
DRFlagSubchannelDataRequested
Indicates that the blockSize passed in includes room for subchannel data. Data producers should check this flag and perform subchannel data production in addition to user fata production. Each block requested from the producer in this case will be formatted as

[user data (as specified in track properties)][subchannel data(96 bytes)].

For example an audio producer callback should repeatedly produce 2352 bytes of audio data into bytes 0-2351 of the block and an additional 96 bytes of subchannel data into bytes 2352-2447.
Discussion

These flags are options for the flags parameter of producePreGapForTrack:intoBuffer:length:atAddress:blockSize:ioFlags: and produceDataForTrack:intoBuffer:length:atAddress:blockSize:ioFlags:.


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Last Updated: 2008-04-01