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QuickTime Atoms

Atoms 0x00000000 Terminates an audio atom list.

struct AudioTerminatorAtom {
long size;
OSType atomType;
};

Fields
size
Discussion

The size in bytes of this atom structure.

atomType
Discussion

Constant kAudioTerminatorAtomType.

Programming Info
C interface file: Sound.h
See Also

For general information about atoms, see Inside QuickTime: QuickTime File Format.

0x00000001 A sprite property matrix atom.

This is a QT leaf atom; it is not declared in the header files. You can create it with QTInsertChild using the following parameters:

Fields
atomType
Discussion

0x00000001.

data
Discussion

The sprite matrix property, a structure of type MatrixRecord.

Parent Atom
'sprt'
Parent atom can contain only one atom of this type.
See Also

For general information about atoms, see Inside QuickTime: QuickTime File Format.

0x00000004 A sprite visible property atom.

This is a QT leaf atom; it is not declared in the header files. You can create it with QTInsertChild using the following parameters:

Fields
atomType
Discussion

0x00000004.

data
Discussion

The sprite visible property, of type short.

Parent Atom
'sprt'
Parent atom can contain only one atom of this type.
See Also

For general information about atoms, see Inside QuickTime: QuickTime File Format.

0x00000005 A sprite property layer atom.

This is a QT leaf atom; it is not declared in the header files. You can create it with QTInsertChild using the following parameters:

Fields
atomType
Discussion

0x00000005.

data
Discussion

The sprite layer property, of type short.

Parent Atom
'sprt'
Parent atom can contain only one atom of this type.
See Also

For general information about atoms, see Inside QuickTime: QuickTime File Format.

0x00000006 A sprite graphics mode property atom.

This is a QT leaf atom; it is not declared in the header files. You can create it with QTInsertChild using the following parameters:

Fields
atomType
Discussion

0x00000006.

data
Discussion

The sprite graphics mode property.

Parent Atom
'sprt'
Parent atom can contain only one atom of this type.
See Also

For general information about atoms, see Inside QuickTime: QuickTime File Format.

0x00000064 A sprite image index atom.

This is a QT leaf atom; it is not declared in the header files. You can create it with QTInsertChild using the following parameters:

Fields
atomType
Discussion

0x00000064.

data
Discussion

The sprite image index property, of type short.

Parent Atom
'sprt'
Parent atom can contain only one atom of this type.
See Also

For general information about atoms, see Inside QuickTime: QuickTime File Format.

0x00000065 A sprite background color property atom.

This is a QT leaf atom; it is not declared in the header files. You can create it with QTInsertChild using the following parameters:

Fields
atomType
Discussion

0x00000065.

data
Discussion

The sprite background color property, a structure of type RGBColor.

See Also

For general information about atoms, see Inside QuickTime: QuickTime File Format.

0x00000066 A sprite property offscreen bit depth atom.

This is a QT leaf atom; it is not declared in the header files. You can create it with QTInsertChild using the following parameters:

Fields
atomType
Discussion

0x00000066.

data
Discussion

The sprite offscreen bit depth property, of type short.

See Also

For general information about atoms, see Inside QuickTime: QuickTime File Format.

0x00000067 A sprite property sample format atom.

This is a QT leaf atom; it is not declared in the header files. You can create it with QTInsertChild using the following parameters:

Fields
atomType
Discussion

0x00000067.

data
Discussion

The sprite sample format property, of type short.

See Also

For general information about atoms, see Inside QuickTime: QuickTime File Format.

'AllF' User data list entry atom to play all frames.

struct MoviesUserData {
long size;
long udType;
char data[1];
};

Fields
size
Discussion

The size in bytes of this atom structure.

udType
Discussion

'AllF'.

data
Discussion

A byte indicating that all frames of video should be played, regardless of timing.

Parent Atom
'udta'
Parent atom can contain only one atom of this type.
Programming Info
C interface file: MoviesFormat.h
See Also

For general information about atoms, see Inside QuickTime: QuickTime File Format.

'beha' Defines sprite behavior.

This is a QT container atom; it is not declared in the header files. You can create it with QTNewAtomContainer and insert it with QTInsertChild, using the following parameter:

Fields
atomType
Discussion

Value is 'beha'.

Optional Child Atoms
'imag'
A sprite image atom.
'crsr'
Color custom cursor child atom.
'sstr'
Specifies the ID of a string variable, contained in a sprite track, to display in the status area of the browser.
See Also

For general information about atoms, see Inside QuickTime: QuickTime File Format.

'chap' Chapter or scene list track reference type atom.

This is a QT leaf atom; it is not declared in the header files. You can create it with QTInsertChild using the following parameters:

Fields
atomType
Discussion

Constant kTrackReferenceChapterList, designating atom type 'chap'.

data
Discussion

A list of track ID values (32-bit integers) specifying the related tracks. Note that a track ID value can be set to 0 to indicate an unused entry in the atom. Doing this can be more convenient than deleting the reference.

Parent Atom
'tref'
Parent atom can contain only one atom of this type.
See Also

For general information about atoms, see Inside QuickTime: QuickTime File Format.

'clip' Defines a clipping region.

struct ClippingAtom {
long size;
long atomType;
RgnAtom aRgnClip;
};

Fields
size
Discussion

The size in bytes of this atom structure.

atomType
Discussion

Constant ClipAID, designating atom type 'clip'.

aRgnClip
Discussion

A 'crgn' atom that defines the clipping region.

Discussion

You can treat this atom either as a declared structure or as a QT atom, which you can create it with QTInsertChild.

Programming Info
C interface file: MoviesFormat.h
See Also

For the atoms that may contain this atom, see 'moov' and 'trak'. For general information about atoms, see Inside QuickTime: QuickTime File Format.

'clon' Contains information about a track clone.

struct CloneAtom {
long size;
long atomType;
CloneRecord cloneInfo;
};

Fields
size
Discussion

The size in bytes of this atom structure.

atomType
Discussion

Value is 'clon'.

cloneInfo
Discussion

A CloneRecord structure.

See Also

See the CloneRecord structure and AddClonedTrackToMovie. For general information about atoms, see Inside QuickTime: QuickTime File Format.

'cmov' Contains a compressed movie.

This is a QT atom; it is not declared in the header files. You can create it with QTInsertChild using the following parameter:

Fields
atomType
Discussion

Constant CompressedMovieAID, designating atom type 'cmov'.

Parent Atom
'moov'
Parent atom can contain only one atom of this type.
Required Child Atoms
'dcom'
Indicates the compression algorithm used to compress a movie. Only one allowed.
'cmvd'
Stores the data for a compressed movie. Only one allowed.
See Also

For general information about atoms, see Inside QuickTime: QuickTime File Format.

'cmvd' Stores the data for a compressed movie.

This is a QT leaf atom; it is not declared in the header files. You can create it with QTInsertChild using the following parameters:

Fields
atomType
Discussion

Constant CompressedMovieDataAID, designating atom type 'cmvd'.

data
Discussion

An integer of type UInt32 that gives the length of the uncompressed movie in bytes, followed by the compressed movie data.

Parent Atom
'cmov'
Parent atom can contain only one atom of this type.
'co64' A 64-bit version of the 'stco' atom.

For details, see 'stco'.

Fields
atomType
Discussion

Constant STChunkOffset64AID, designating atom type 'co64'.

See Also

For general information about atoms, see Inside QuickTime: QuickTime File Format.

'©cpy' User data list entry atom: copyright information.

struct MoviesUserData {
long size;
long udType;
char data[1];
};

Fields
size
Discussion

The size in bytes of this atom structure.

udType
Discussion

Constant kUserDataTextCopyright, designating atom type '©cpy'.

data
Discussion

A string containing copyright information.

Parent Atom
'udta'
Parent atom can contain only one atom of this type.
Programming Info
C interface file: MoviesFormat.h
See Also

For general information about atoms, see Inside QuickTime: QuickTime File Format.

'©day' User data list entry atom: creation date.

struct MoviesUserData {
long size;
long udType;
char data[1];
};

Fields
size
Discussion

The size in bytes of this atom structure.

udType
Discussion

Constant kUserDataTextCreationDate, designating atom type '©day'.

data
Discussion

A string containing the creation date.

Parent Atom
'udta'
Parent atom can contain only one atom of this type.
Programming Info
C interface file: MoviesFormat.h
See Also

For general information about atoms, see Inside QuickTime: QuickTime File Format.

'©dir' User data list entry atom: name of movie's director.

struct MoviesUserData {
long size;
long udType;
char data[1];
};

Fields
size
Discussion

The size in bytes of this atom structure.

udType
Discussion

Constant kUserDataTextDirector, designating atom type '©dir'.

data
Discussion

A string containing the name of the movie's director.

Parent Atom
'udta'
Parent atom can contain only one atom of this type.
Programming Info
C interface file: MoviesFormat.h
See Also

For general information about atoms, see Inside QuickTime: QuickTime File Format.

'©ed1' User data list entry atom: edit date 1.

struct MoviesUserData {
long size;
long udType;
char data[1];
};

Fields
size
Discussion

The size in bytes of this atom structure.

udType
Discussion

Constant kUserDataTextEditDate1, designating atom type '©ed1'.

data
Discussion

A string containing the first edit date.

Parent Atom
'udta'
Parent atom can contain only one atom of this type.
Discussion

Similar atoms of types '©ed2' through '©ed9' may contain other edit date strings.

Programming Info
C interface file: MoviesFormat.h
See Also

For general information about atoms, see Inside QuickTime: QuickTime File Format.

'©fmt' User data list entry atom: indication of movie's format.

struct MoviesUserData {
long size;
long udType;
char data[1];
};

Fields
size
Discussion

The size in bytes of this atom structure.

udType
Discussion

Constant kUserDataTextOriginalFormat, designating atom type '©fmt'.

data
Discussion

A string indicating the movie's format.

Parent Atom
'udta'
Parent atom can contain only one atom of this type.
Programming Info
C interface file: MoviesFormat.h
See Also

For general information about atoms, see Inside QuickTime: QuickTime File Format.

'©inf' User data list entry atom: information about the movie.

struct MoviesUserData {
long size;
long udType;
char data[1];
};

Fields
size
Discussion

The size in bytes of this atom structure.

udType
Discussion

Constant kUserDataTextInformation, designating atom type '©inf'.

data
Discussion

A string containing information about the movie.

Parent Atom
'udta'
Parent atom can contain only one atom of this type.
Programming Info
C interface file: MoviesFormat.h
See Also

For general information about atoms, see Inside QuickTime: QuickTime File Format.

'©prd' User data list entry atom: name of movie's producer.

struct MoviesUserData {
long size;
long udType;
char data[1];
};

Fields
size
Discussion

The size in bytes of this atom structure.

udType
Discussion

Constant kUserDataTextProducer, designating atom type '©prd'.

data
Discussion

A string containing the name of the movie's producer.

Parent Atom
'udta'
Parent atom can contain only one atom of this type.
Programming Info
C interface file: MoviesFormat.h
See Also

For general information about atoms, see Inside QuickTime: QuickTime File Format.

'©prf' User data list entry atom: names of performers.

struct MoviesUserData {
long size;
long udType;
char data[1];
};

Fields
size
Discussion

The size in bytes of this atom structure.

udType
Discussion

Constant kUserDataTextPerformers, designating atom type '©prf'.

data
Discussion

A string containing names of the performers.

Parent Atom
'udta'
Parent atom can contain only one atom of this type.
Programming Info
C interface file: MoviesFormat.h
See Also

For general information about atoms, see Inside QuickTime: QuickTime File Format.

'©req' User data list entry atom: special hardware or software requirements.

struct MoviesUserData {
long size;
long udType;
char data[1];
};

Fields
size
Discussion

The size in bytes of this atom structure.

udType
Discussion

Constant kUserDataTextSpecialPlaybackRequirements, designating atom type '©req'.

data
Discussion

A string detailing special hardware or software requirements.

Parent Atom
'udta'
Parent atom can contain only one atom of this type.
Programming Info
C interface file: MoviesFormat.h
See Also

For general information about atoms, see Inside QuickTime: QuickTime File Format.

'©src' User data list entry atom: credits for those who provided movie source content.

struct MoviesUserData {
long size;
long udType;
char data[1];
};

Fields
size
Discussion

The size in bytes of this atom structure.

udType
Discussion

Constant kUserDataTextOriginalSource, designating atom type '©src'.

data
Discussion

A string containing credits for those who provided movie source content.

Parent Atom
'udta'
Parent atom can contain only one atom of this type.
Programming Info
C interface file: MoviesFormat.h
See Also

For general information about atoms, see Inside QuickTime: QuickTime File Format.

'©wrt' User data list entry atom: name of movie's writer.

struct MoviesUserData {
long size;
long udType;
char data[1];
};

Fields
size
Discussion

The size in bytes of this atom structure.

udType
Discussion

Constant kUserDataTextWriter, designating atom type '©wrt'.

data
Discussion

A string containing the name of the movie's writer.

Parent Atom
'udta'
Parent atom can contain only one atom of this type.
Programming Info
C interface file: MoviesFormat.h
See Also

For general information about atoms, see Inside QuickTime: QuickTime File Format.

'crgn' Defines a clipping region.

struct RgnAtom {
long size;
long atomType;
short rgnSize;
Rect rgnBBox;
char data[1];
};

Fields
size
Discussion

The size in bytes of this atom structure.

atomType
Discussion

Constant RgnClipAID, designating atom type 'crgn'.

rgnSize
Discussion

The size in bytes of the region.

rgnBBox
Discussion

The bounding box for the region.

data
Discussion

Additional data if the clipping region is not rectangular.

Parent Atom
'clip'
Parent atom can contain only one atom of this type.
Programming Info
C interface file: MoviesFormat.h
See Also

For general information about atoms, see Inside QuickTime: QuickTime File Format.

'crsr' Color custom cursor child atom.

This is a QT leaf atom; it is not declared in the header files. You can create it with QTInsertChild using the following parameters:

Fields
atomType
Discussion

Constant kSpriteCursorBehaviorAtomType, designating atom type 'crsr'.

data
Discussion

A cursor description.

Parent Atom
'vrcp'
Parent atom can contain multiple atoms of this type.
See Also

For general information about atoms, see Inside QuickTime: QuickTime File Format.

'cspd' Contains the connection speed currently set in the QuickTime preferences.

This is a QT leaf atom; it is not declared in the header files. You can create it with QTInsertChild using the following parameters:

Fields
atomType
Discussion

Constant ConnectionSpeedPrefsType, designating atom type 'cspd'.

data
Discussion

The connection speed.

See Also

See the GetQuickTimePreference and SetQuickTimePreference functions. For general information about atoms, see Inside QuickTime: QuickTime File Format.

'ctab' Color table atom.

This is a QT leaf atom; it is not declared in the header files. You can create it with QTInsertChild using the following parameters:

Fields
atomType
Discussion

Constant ColorTableAID, designating atom type 'ctab'.

data
Discussion

A color table.

Parent Atom
'moov'
Parent atom can contain only one atom of this type.
Discussion

Color table atoms define a list of preferred colors for displaying the movie on devices that support only 256 colors. The list may contain up to 256 colors.

See Also

For general information about atoms, see Inside QuickTime: QuickTime File Format.

'cufa' Non-standard cubic QTVR panorama data atom.

This is a QT leaf atom; it is not declared in the header files. You can create it with QTInsertChild using the following parameters:

Fields
atomType
Discussion

Value is 'cufa'.

data
Discussion

A QTVRCubicFaceData structure.

Discussion

Each entry in the QTVRCubicFaceData structure describes one face of the polyhedron being described.

See Also

For general information about atoms, see Inside QuickTime: QuickTime File Format.

'CURS' Custom cursor child atom.

This is a QT leaf atom; it is not declared in the header files. You can create it with QTInsertChild using the following parameters:

Fields
atomType
Discussion

Constant kQTVRCursorAtomType, designating atom type 'CURS'.

data
Discussion

A cursor description.

Parent Atom
'vrcp'
Parent atom can contain multiple atoms of this type.
See Also

For general information about atoms, see Inside QuickTime: QuickTime File Format.

'cuvw' Cubic view atom.

This is a QT leaf atom; it is not declared in the header files. You can create it with QTInsertChild using the following parameters:

Fields
atomType
Discussion

Value is 'cuvw'.

data
Discussion

A QTVRCubicViewAtom structure.

See Also

For general information about atoms, see Inside QuickTime: QuickTime File Format.

'dasz' Data size atom.

This is a QT leaf atom; it is not declared in the header files. You can create it with QTInsertChild using the following parameters:

Fields
atomType
Discussion

Constant kQTTargetDataSize, designating atom type 'dasz'.

data
Discussion

A QTTargetDataSize structure.

Parent Atom
'vide'
Parent atom can contain only one atom of this type.
See Also

For general information about atoms, see Inside QuickTime: QuickTime File Format.

'dcom' Indicates the compression algorithm used to compress a movie.

This is a QT leaf atom; it is not declared in the header files. You can create it with QTInsertChild using the following parameters:

Fields
atomType
Discussion

Constant DataCompressionAtomAID, designating atom type 'dcom'.

data
Discussion

A 32-bit constant (see below) that indicates which lossless algorithm was used to compress the movie contained in the parent atom.

Data Constants
AppleDataCompressorSubType
The Apple data compressor; value is 'adec'.
zlibDataCompressorSubType
The zlib data compressor; value is 'zlib'.
Parent Atom
'cmov'
Parent atom can contain only one atom of this type.
See Also

For general information about atoms, see Inside QuickTime: QuickTime File Format.

'defi' A sprite image data reference atom.

This is a QT leaf atom; it is not declared in the header files. You can create it with QTInsertChild using the following parameters:

Fields
atomType
Discussion

Constant kSpriteImageDefaultImageIndexAtomType, designating atom type 'defi'.

data
Discussion

The image index of a traditional image, of type short, to use while waiting for the referenced image to load.

Parent Atom
'imag'
Parent atom can contain only one atom of this type.
Discussion

You use the this atom type to specify that an image is referenced and how to access it. Its ID should be 1.

Version Notes

Added to QuickTime 4.

See Also

For general information about atoms, see Inside QuickTime: QuickTime File Format.

'desc' Graphics export description atom.

This is a QT leaf atom; it is not declared in the header files. You can create it with QTInsertChild using the following parameters:

Fields
atomType
Discussion

Constant kCustomHandlerDesc, designating atom type 'desc'.

data
Discussion

A nonterminated string containing a human-readable format name.

Parent Atom
'expo'
Parent atom can contain only one atom of this type.
See Also

See the GraphicsExportGetMIMETypeList and GraphicsImportGetExportImageTypeList functions. For general information about atoms, see Inside QuickTime: QuickTime File Format.

'dflt' Key frame shared-data atom.

This is a QT atom; it is not declared in the header files. You can create it with QTInsertChild using the following parameter:

Fields
atomType
Discussion

Constant kSpriteSharedDataAtomType, designating atom type 'dflt'.

Required Child Atoms
'imct'
Only one allowed.
See Also

For general information about atoms, see Inside QuickTime: QuickTime File Format.

'dimm' Number of bytes of immediate data to be sent.

This is a QT leaf atom; it is not declared in the header files. You can create it with QTInsertChild using the following parameters:

Fields
atomType
Discussion

Value is 'dimm'.

data
Discussion

8-byte value.

Parent Atom
'hinf'
Parent atom can contain only one atom of this type.
See Also

For general information about atoms, see Inside QuickTime: QuickTime File Format.

'dinf' Specifies where media data is stored.

struct DataInfoAtom {
long size;
long atomType;
DataRefAtom dataRef;
};

Fields
size
Discussion

The size in bytes of this atom structure.

atomType
Discussion

Constant DataInfoAID, designating atom type 'dinf'.

dataRef
Discussion

A value that contains the data for this atom. The 4-byte DataRefAtom data type is private and is not documented.

Optional Child Atoms
'dref'
Only one allowed.
Programming Info
C interface file: MoviesFormat.h
See Also

For general information about atoms, see Inside QuickTime: QuickTime File Format.

'dmax' The largest packet duration.

This is a QT leaf atom; it is not declared in the header files. You can create it with QTInsertChild using the following parameters:

Fields
atomType
Discussion

Value is 'dmax'.

data
Discussion

4 bytes packet duration, in milliseconds.

Parent Atom
'hinf'
Parent atom can contain only one atom of this type.
See Also

For general information about atoms, see Inside QuickTime: QuickTime File Format.

'dmed' Number of bytes from the media track to be sent.

This is a QT leaf atom; it is not declared in the header files. You can create it with QTInsertChild using the following parameters:

Fields
atomType
Discussion

Value is 'dmed'.

data
Discussion

8-byte value.

Parent Atom
'hinf'
Parent atom can contain only one atom of this type.
See Also

For general information about atoms, see Inside QuickTime: QuickTime File Format.

'dref' Data reference atom.

This is a QT leaf atom; it is not declared in the header files. You can create it with QTInsertChild using the following parameters:

Fields
atomType
Discussion

Constant DataRefAID, designating atom type 'dref'.

data
Discussion

Data references.

Parent Atom
'dinf'
Parent atom can contain only one atom of this type.
See Also

See the AliasRecord structure. For general information about atoms, see Inside QuickTime: QuickTime File Format.

'drep' Number of bytes of repeated data to be sent.

This is a QT leaf atom; it is not declared in the header files. You can create it with QTInsertChild using the following parameters:

Fields
atomType
Discussion

Value is 'drep'.

data
Discussion

8-byte value.

Parent Atom
'hinf'
Parent atom can contain only one atom of this type.
See Also

For general information about atoms, see Inside QuickTime: QuickTime File Format.

'edts' Contains an atom that defines an edit list.

struct EditsAtom {
long size;
long atomType;
EditListAtom editList;
};

Fields
size
Discussion

The size in bytes of this atom structure.

atomType
Discussion

Constant EditsAID, designating atom type 'edts'.

editList
Discussion

An 'elst' atom.

Parent Atom
'trak'
Parent atom can contain only one atom of this type.
Required Child Atoms
'elst'
Only one allowed.
Programming Info
C interface file: MoviesFormat.h
See Also

For general information about atoms, see Inside QuickTime: QuickTime File Format.

'elst' Contains a list of edit segment definitions for a media.

struct EditListAtom {
long size;
long atomType;
long flags;
long numEntries;
EditListType editListTable[1];
};

Fields
size
Discussion

The size in bytes of this atom structure.

atomType
Discussion

Constant EditListAID, designating atom type 'elst'.

flags
Discussion

One byte of version information followed by three bytes of flags. The flag bytes are not currently used.

numEntries
Discussion

The number of entries in editListTable.

editListTable
Discussion

An array of EditListType data structures, each of which locates and defines an edit segment within a media.

Parent Atom
'edts'
Parent atom can contain only one atom of this type.
Discussion

You can use the edit list atom to tell QuickTime how to map from a time in a movie to a time in a media, and ultimately to each segment of the media's data.

Programming Info
C interface file: MoviesFormat.h
See Also

For general information about atoms, see Inside QuickTime: QuickTime File Format.

'end ' Defines the ending offset of hypertext in a text stream.

This is a QT leaf atom; it is not declared in the header files. You can create it with QTInsertChild using the following parameters:

Fields
atomType
Discussion

Value is 'end ' (the fourth character is a space).

data
Discussion

The ending offset of hypertext in a text stream.

Parent Atom
'htxt'
Parent atom can contain only one atom of this type.
See Also

For general information about atoms, see Inside QuickTime: QuickTime File Format.

'enda' Determines the endian status of the sound component that interprets data contained in an audio atom list.

struct AudioEndianAtom {
long size;
OSType atomType;
short littleEndian;
};

Fields
size
Discussion

The size in bytes of this atom structure.

atomType
Discussion

Constant kAudioEndianAtomType, designating atom type 'enda'.

littleEndian
Discussion

Set this field to TRUE if the audio component is to operate on little-endian data, and FALSE otherwise.

Programming Info
C interface file: Sound.h
See Also

To choose the sound component for an audio atom list, see the 'frma' atom. For general information about atoms, see Inside QuickTime: QuickTime File Format.

'expo' Defines a graphics export group.

This is a QT container atom; it is not declared in the header files. You can create it with QTNewAtomContainer and insert it with QTInsertChild, using the following parameters:

Fields
atomType
Discussion

Constant kGraphicsExportGroup, designating atom type 'expo'.

Required Child Atoms
'ftyp'
An OSType representing the exported file type.
'ext '
A nonterminated string containing the suggested file extension for this format.
'desc'
A nonterminated string containing a human-readable name for this format.
Optional Child Atoms
'mime'[atom]
A nonterminated string containing the MIME type for this format.
See Also

See the GraphicsImportGetExportImageTypeList function. For general information about atoms, see Inside QuickTime: QuickTime File Format.

'ext ' Defines a graphics export extension.

This is a QT leaf atom; it is not declared in the header files. You can create it with QTInsertChild using the following parameters:

Fields
atomType
Discussion

Constant kGraphicsExportExtension, designating atom type 'ext ' (the fourth character is a space).

data
Discussion

A nonterminated string containing a file extension.

Parent Atom
'expo'
Parent atom can contain only one atom of this type.
See Also

See the GraphicsImportGetExportImageTypeList function. For general information about atoms, see Inside QuickTime: QuickTime File Format.

'flap' Extension to the SoundDescription structure.

This is a QT leaf atom; it is not declared in the header files. You can create it with QTInsertChild using the following parameters:

Fields
atomType
Discussion

Constant siSlopeAndIntercept, designating atom type 'flap'; see Sound Information Selectors.

data
Discussion

A SoundSlopeAndInterceptRecord structure.

See Also

For general information about atoms, see Inside QuickTime: QuickTime File Format.

'flov' Contains a floating-point variable for a sprite.

This is a QT container atom; it is not declared in the header files. You can create it with QTNewAtomContainer and insert it with QTInsertChild, using the following parameter:

Fields
atomType
Discussion

Value is 'flov'.

Parent Atom
'vars'
Contains variables for a sprite.
See Also

For general information about atoms, see Inside QuickTime: QuickTime File Format.

'free' Provides unused space in a movie file.

This is a QT leaf atom; it is not declared in the header files. You can create it with QTInsertChild using the following parameters:

Fields
atomType
Discussion

Constant FreeAtomType, designating atom type 'free'.

data
Discussion

Any number of bytes of free space.

See Also

For general information about atoms, see Inside QuickTime: QuickTime File Format.

'frma' Specifies which sound component is responsible for the atoms contained in an audio atom list.

struct AudioFormatAtom {
long size;
OSType atomType;
OSType format;
};

Fields
size
Discussion

The size in bytes of this atom structure.

atomType
Discussion

Constant kAudioFormatAtomType, designating atom type 'frma'.

format
Discussion

A constant that identifies a sound component. See Codec Identifiers.

Programming Info
C interface file: Sound.h
See Also

For general information about atoms, see Inside QuickTime: QuickTime File Format.

'ftyp' Defines a graphics export file type.

This is a QT leaf atom; it is not declared in the header files. You can create it with QTInsertChild using the following parameters:

Fields
atomType
Discussion

Constant kGraphicsExportFileType, designating atom type 'ftyp'.

data
Discussion

An OSType representing the exported file type.

Parent Atom
'expo'
Parent atom can contain only one atom of this type.
See Also

See the GraphicsImportGetExportImageTypeList function. For general information about atoms, see Inside QuickTime: QuickTime File Format.

'gmhd' Contains a generic media information atom.

This is a QT container atom; it is not declared in the header files. You can create it with QTNewAtomContainer and insert it with QTInsertChild, using the following parameter:

Fields
atomType
Discussion

Constant GenericMediaInfoHeaderAID, designating atom type 'gmhd'.

Parent Atom
'minf'[generic]
Parent atom can contain only one atom of this type.
Required Child Atoms
'gmin'
Provides data that is specific to a handler for media other than video or sound. Only one allowed.
Discussion

This atom is currently used only as a container for a 'gmin' atom.

See Also

For general information about atoms, see Inside QuickTime: QuickTime File Format.

'gmin' Provides data that is specific to a handler for media other than video or sound.

This is a QT leaf atom; it is not declared in the header files. You can create it with QTInsertChild using the following parameters:

Fields
atomType
Discussion

Constant GenericMediaInfoAID, designating atom type 'gmin'.

data
Discussion

Data required by the media handler that is designated by the 'hdlr' atom contained in the 'minf'[generic] atom that also contains the parent of this atom.

Parent Atom
'gmhd'
Parent atom can contain any number of atoms of this type.
Discussion

This atom contains handler-specific information to support your use of a 'minf'[generic] atom. Note that the data in this atom is not used by RTP servers.

See Also

For general information about atoms, see Inside QuickTime: QuickTime File Format.

'hdlr' Specifies the component that is to interpret a media's data.

struct HandlerAtom {
long size;
long atomType;
PublicHandlerInfo hInfo;
};

Fields
size
Discussion

The size in bytes of this atom structure.

atomType
Discussion

Constant HandlerAID, designating atom type 'hdlr'.

hInfo
Discussion

A PublicHandlerInfo structure, which contains the actual data for this atom.

Discussion

RTP servers ignore this atom's data when it is contained in a 'minf'[generic] atom.

Programming Info
C interface file: MoviesFormat.h
See Also

For the atoms that may contain this atom, see 'mdia', 'minf'[generic], 'minf'[sound], and 'minf'[video]. For general information about atoms, see Inside QuickTime: QuickTime File Format.

'hinf' Contains statistics for the hint track.

This is a QT container atom; it is not declared in the header files. You can create it with QTNewAtomContainer and insert it with QTInsertChild, using the following parameter:

Fields
atomType
Discussion

Value is 'hinf'.

Required Child Atoms
'trpy'
Total number of bytes that will be sent, including 12-byte RTP headers but not including network headers. Only one allowed.
'nump'
Total number of network packets that will be sent. Only one allowed.
'tpyl'
Total number of bytes that will be sent, not including 12-byte RTP headers. Only one allowed.
'maxr'
Maximum data rate. Only one allowed.
'dmed'
Number of bytes from the media track to be sent. Only one allowed.
'dimm'
Number of bytes of immediate data to be sent. Only one allowed.
'drep'
Number of bytes of repeated data to be sent. Only one allowed.
'tmin'
Smallest relative transmission time, in milliseconds. Only one allowed.
'tmax'
Largest relative transmission time, in milliseconds. Only one allowed.
'pmax'
Largest packet, in bytes, including 12-byte RTP header. Only one allowed.
'dmax'
The largest packet duration. Only one allowed.
'payt'
Payload type. Only one allowed.
See Also

For general information about atoms, see Inside QuickTime: QuickTime File Format.

'hint' Hint track reference type atom.

This is a QT leaf atom; it is not declared in the header files. You can create it with QTInsertChild using the following parameters:

Fields
atomType
Discussion

Value is 'hint'.

data
Discussion

A list of track ID values (32-bit integers) specifying the related tracks. Note that a track ID value can be set to 0 to indicate an unused entry in the atom. Doing this can be more convenient than deleting the reference.

Parent Atom
'tref'
Parent atom can contain only one atom of this type.
See Also

For general information about atoms, see Inside QuickTime: QuickTime File Format.

'hlit' Defines the highlighted portion in text.

struct HiliteAtom {
long size;
long atomType;
long selStart;
long selEnd;
};

Fields
size
Discussion

The size in bytes of this atom structure.

atomType
Discussion

Value is 'hlit'.

selStart
Discussion

Character number of highlighted selection start character.

selEnd
Discussion

Character number of highlighted selection end character.

Discussion

For general information about atoms, see Inside QuickTime: QuickTime File Format.

Programming Info
C interface file: MoviesFormat.h
'hnti' Hint track user data atom.

This is a QT container atom; it is not declared in the header files. You can create it with QTNewAtomContainer and insert it with QTInsertChild, using the following parameter:

Fields
atomType
Discussion

Value is 'hnti'.

Required Child Atoms
'sdp '
SDP text for a hint track. Only one allowed.
See Also

For general information about atoms, see Inside QuickTime: QuickTime File Format.

'hots' A QTVR hot spot.

This is a QT container atom; it is not declared in the header files. You can create it with QTNewAtomContainer and insert it with QTInsertChild, using the following parameter:

Fields
atomType
Discussion

Constant kQTVRHotSpotAtomType, designating atom type 'hots'.

Parent Atom
'hspa'
Parent atom can contain any number of atoms of this type.
Required Child Atoms
'hsin'
Contains general hot spot information. Only one allowed.
'link'
Specific information about a link hot spot. Only one allowed.
See Also

For general information about atoms, see Inside QuickTime: QuickTime File Format.

'hsin' Contains general hot spot information.

This is a QT leaf atom; it is not declared in the header files. You can create it with QTInsertChild using the following parameters:

Fields
atomType
Discussion

Constant kQTVRHotSpotInfoAtomType, designating atom type 'hsin'.

data
Discussion

Hot spot information.

Parent Atom
'hots'
Parent atom can contain only one atom of this type.
See Also

For general information about atoms, see Inside QuickTime: QuickTime File Format.

'hspa' Hot spot parent atom.

This is a QT container atom; it is not declared in the header files. You can create it with QTNewAtomContainer and insert it with QTInsertChild, using the following parameter:

Fields
atomType
Discussion

Constant kQTVRHotSpotParentAtomType, designating atom type 'hspa'.

Parent Atom
'vrnp'
Parent atom can contain only one atom of this type.
Required Child Atoms
'hots'
A QTVR hot spot. Any number allowed.
See Also

For general information about atoms, see Inside QuickTime: QuickTime File Format.

'htxt' Hypertext in a text stream.

This is a QT container atom; it is not declared in the header files. You can create it with QTNewAtomContainer and insert it with QTInsertChild, using the following parameter:

Fields
atomType
Discussion

Value is 'htxt'.

Parent Atom
'wtxt'
Parent atom can contain multiple atoms of this type.
Required Child Atoms
'strt'
Defines the starting offset of hypertext in a text stream. Only one allowed.
'end '
Defines the ending offset of hypertext in a text stream. Only one allowed.
See Also

For general information about atoms, see Inside QuickTime: QuickTime File Format.

'idat' Image data atom.

This is a QT leaf atom; it is not declared in the header files. You can create it with QTInsertChild using the following parameters:

Fields
atomType
Discussion

Constant quickTimeImageFileImageDataAtom, designating atom type 'idat'.

data
Discussion

The image data.

See Also

For general information about atoms, see Inside QuickTime: QuickTime File Format.

'idsc' Image description atom.

This is a QT leaf atom; it is not declared in the header files. You can create it with QTInsertChild using the following parameters:

Fields
atomType
Discussion

Constant quickTimeImageFileImageDescriptionAtom, designating atom type 'idsc'.

data
Discussion

The image description.

See Also

For general information about atoms, see Inside QuickTime: QuickTime File Format.

'iicc' ColorSync profile atom.

This is a QT leaf atom; it is not declared in the header files. You can create it with QTInsertChild using the following parameters:

Fields
atomType
Discussion

Constant quickTimeImageFileColorSyncProfileAtom, designating atom type 'iicc'.

data
Discussion

A ColorSync profile.

Version Notes

This is a new optional atom in QuickTime 4.

See Also

See the GraphicsExportSetColorSyncProfile function. For general information about atoms, see Inside QuickTime: QuickTime File Format.

'imag' A sprite image atom.

This is a QT container atom; it is not declared in the header files. You can create it with QTNewAtomContainer and insert it with QTInsertChild, using the following parameter:

Fields
atomType
Discussion

Constant kSpriteImageAtomType, designating atom type 'imag'.

Parent Atom
'imct'
Parent atom can contain any number of atoms of this type.
Required Child Atoms
'imda'
Contains sprite image data. Only one allowed.
Optional Child Atoms
'name'[sprite]
A sprite name atom. Only one allowed.
See Also

For general information about atoms, see Inside QuickTime: QuickTime File Format.

'imap' An input map.

This is a QT container atom; it is not declared in the header files. You can create it with QTNewAtomContainer and insert it with QTInsertChild, using the following parameter:

Fields
atomType
Discussion

Constant InputMapAID, designating atom type 'imap'.

Parent Atom
'trak'
Parent atom can contain only one atom of this type.
Required Child Atoms
' in'
Track input atom. Only one allowed.
See Also

For general information about atoms, see Inside QuickTime: QuickTime File Format.

'imct' A sprite image container atom.

This is a QT container atom; it is not declared in the header files. You can create it with QTNewAtomContainer and insert it with QTInsertChild, using the following parameter:

Fields
atomType
Discussion

Constant kSpriteImagesContainerAtomType, designating atom type 'imct'.

Parent Atom
'dflt'
Parent atom can contain only one atom of this type.
Required Child Atoms
'imag'
Sprite image atom. Any number allowed.
See Also

For general information about atoms, see Inside QuickTime: QuickTime File Format.

'imda' A sprite image data.

This is a QT leaf atom; it is not declared in the header files. You can create it with QTInsertChild using the following parameters:

Fields
atomType
Discussion

Constant kSpriteImageDataAtomType, designating atom type 'imda'.

data
Discussion

Image data.

Parent Atom
'imag'
Parent atom can contain only one atom of this type.
See Also

For general information about atoms, see Inside QuickTime: QuickTime File Format.

'imgp' Panorama imaging parent atom.

This is a QT container atom; it is not declared in the header files. You can create it with QTNewAtomContainer and insert it with QTInsertChild, using the following parameter:

Fields
atomType
Discussion

Constant kQTVRImagingParentAtomType, designating atom type 'imgp'.

Required Child Atoms
'impn'
Panorama imaging atom. Any number allowed.
See Also

For general information about atoms, see Inside QuickTime: QuickTime File Format.

'imgr' A sprite image group ID atom.

This is a QT leaf atom; it is not declared in the header files. You can create it with QTInsertChild using the following parameters:

Fields
atomType
Discussion

Constant kSpriteImageGroupIDAtomType, designating atom type 'imgr'.

data
Discussion

The group ID, of type long.

Parent Atom
'imag'
Parent atom can contain only one atom of this type.
Discussion

Each image in a sprite media key frame sample is assigned to a group. Add an atom of this type as a child of the 'imag' atom and set its leaf data to a long containing the group ID. For example, if the sample contains ten images where the first two images are equivalent, and the last eight images are equivalent, then you could assign a group ID of 1000 to the first two images, and a group ID of 1001 to the last eight images. This divides the images in the sample into two sets. The actual ID does not matter, it just needs to be a unique positive integer. Note that you must assign group IDs to your sprite sample if you want a sprite to display images with non-equivalent image descriptions (i.e., images with different dimensions).

Special Considerations

Although QuickTime does not currently use this atom internally, tools that edit sprite media can use the information provided to optimize certain operations, such as cut, copy, and paste.

See Also

For general information about atoms, see Inside QuickTime: QuickTime File Format.

'impn' Panorama imaging atom.

This is a QT leaf atom; it is not declared in the header files. You can create it with QTInsertChild using the following parameters:

Fields
atomType
Discussion

Constant kQTVRPanoImagingAtomType, designating atom type 'impn'.

data
Discussion

A QTVRPanoImagingAtom structure.

Parent Atom
'imgp'
Parent atom can contain any number of atoms of this type.
Discussion

A QTVRPanoImagingAtom describes the default imaging characteristics for all the panoramic nodes in a scene. This atom overrides QuickTime VR's own defaults.

See Also

For general information about atoms, see Inside QuickTime: QuickTime File Format.

'imre' A sprite image data reference atom.

This is a QT leaf atom; it is not declared in the header files. You can create it with QTInsertChild using the following parameters:

Fields
atomType
Discussion

Constant kSpriteImageDataRefAtomType, designating atom type 'imre'.

data
Discussion

The data reference, which is similar to the dataRef parameter of GetDataHandler.

Parent Atom
'imag'
Parent atom can contain only one atom of this type.
Discussion

You use the this atom type to specify that an image is referenced and how to access it. Add this atom as a child of the 'imag' atom instead of an 'imda' atom. Its ID should be 1.

Version Notes

Added in QuickTime 4.

See Also

See the GetDataHandler function. For general information about atoms, see Inside QuickTime: QuickTime File Format.

'imrg' Custom sprite image registration point atom.

This is a QT leaf atom; it is not declared in the header files. You can create it with QTInsertChild using the following parameters:

Fields
atomType
Discussion

Constant kSpriteImageRegistrationAtomType, designating atom type 'imrg'.

data
Discussion

The desired sprite registration point, a FixedPoint structure.

Parent Atom
'imag'
Parent atom can contain only one atom of this type.
Discussion

Sprite images have a default registration point of 0, 0. To specify a different point, add an atom of this type as a child atom of the 'imag' and set its leaf data to a FixedPoint value with the desired registration point.

See Also

For general information about atoms, see Inside QuickTime: QuickTime File Format.

'imrt' A sprite image data reference type atom.

This is a QT leaf atom; it is not declared in the header files. You can create it with QTInsertChild using the following parameters:

Fields
atomType
Discussion

Constant kSpriteImageDataRefTypeAtomType, designating atom type 'imrt'.

data
Discussion

The data reference type, which is similar to the dataRefType parameter of GetDataHandler.

Parent Atom
'imag'
Parent atom can contain only one atom of this type.
Discussion

You use the this atom type to specify that an image is referenced and how to access it. Add this atom as a child of the 'imag' atom. Its ID should be 1.

Version Notes

Added in QuickTime 4.

See Also

See the GetDataHandler function. For general information about atoms, see Inside QuickTime: QuickTime File Format.

' in' Track input atom.

This is a QT container atom; it is not declared in the header files. You can create it with QTNewAtomContainer and insert it with QTInsertChild, using the following parameter:

Fields
atomType
Discussion

Value ' in'; the first two characters are spaces.

Parent Atom
'imap'
Parent atom can contain only one atom of this type.
Required Child Atoms
' ty'
Input atom type. Only one allowed.
Optional Child Atoms
'obid'
Object ID atom. Only one allowed.
See Also

For general information about atoms, see Inside QuickTime: QuickTime File Format.

'kmat' Defines a matte for a track's compressed media.

struct MatteCompressedAtom {
long size;
long atomType;
long flags;
ImageDescription matteImageDescription;
char matteData[1];
};

Fields
size
Discussion

The size in bytes of this atom structure.

atomType
Discussion

Constant MatteCompAID, designating atom type 'kmat'.

flags
Discussion

One byte of version information followed by three bytes of flags. The flags bytes are not currently used.

matteImageDescription
Discussion

An ImageDescription data structure for the matte.

matteData
Discussion

An array of matte data.

Programming Info
C interface file: MoviesFormat.h
See Also

For the structure that contains this atom, see the 'matt' atom. For general information about atoms, see Inside QuickTime: QuickTime File Format.

'link' Contains specific information about a link hot spot.

This is a QT leaf atom; it is not declared in the header files. You can create it with QTInsertChild using the following parameters:

Fields
atomType
Discussion

Constant kQTVRLinkInfoAtomType, designating atom type 'link'.

data
Discussion

Link hot spot information.

See Also

For general information about atoms, see Inside QuickTime: QuickTime File Format.

'load' Contains preloading information for a track.

struct TrackLoadSettingsAtom {
long size;
long atomType;
TrackLoadSettings settings;
};

Fields
size
Discussion

The size in bytes of this atom structure.

atomType
Discussion

Constant LoadSettingsAID, designating atom type 'load'.

settings
Discussion

A TrackLoadSettings data structure, which contains the actual data for this atom.

Programming Info
C interface file: MoviesFormat.h
See Also

For general information about atoms, see Inside QuickTime: QuickTime File Format.

'LOOP' User data list entry atom: looping style.

struct MoviesUserData {
long size;
long udType;
char data[1];
};

Fields
size
Discussion

The size in bytes of this atom structure.

udType
Discussion

Value is 'LOOP'.

data
Discussion

A long integer, indicating looping style: 0 for normal looping, 1 for palindromic looping.

Parent Atom
'udta'
Parent atom can contain only one atom of this type.
Discussion

This atom is present only if the movie is set to loop.

Programming Info
C interface file: MoviesFormat.h
See Also

See the MoviesUserData structure. For general information about atoms, see Inside QuickTime: QuickTime File Format.

'matt' Defines a matte for a track's media.

struct MatteAtom {
long size;
long atomType;
MatteCompressedAtom aCompressedMatte;
};

Fields
size
Discussion

The size in bytes of this atom structure.

atomType
Discussion

Constant MatteAID, designating atom type 'matt'.

aCompressedMatte
Discussion

A 'kmat' atom.

Required Child Atoms
'kmat'
Only one allowed.
Programming Info
C interface file: MoviesFormat.h
See Also

For general information about atoms, see Inside QuickTime: QuickTime File Format.

'maxr' Maximum data rate.

This is a QT leaf atom; it is not declared in the header files. You can create it with QTInsertChild using the following parameters:

Fields
atomType
Discussion

Value is 'maxr'.

data
Discussion

8 bytes.

Parent Atom
'hinf'
Parent atom can contain only one atom of this type.
See Also

For general information about atoms, see Inside QuickTime: QuickTime File Format.

'mdat' Media data atom.

This is a QT leaf atom; it is not declared in the header files. You can create it with QTInsertChild using the following parameters:

Fields
atomType
Discussion

Constant MovieDataAtomType, designating atom type 'mdat'.

data
Discussion

Media data.

See Also

For general information about atoms, see Inside QuickTime: QuickTime File Format.

'mdhd' Specifies the characteristics of a media.

struct MediaHeaderAtom {
long size;
long atomType;
MediaHeader header;
};

Fields
size
Discussion

The size in bytes of this atom structure.

atomType
Discussion

Constant MediaHeaderAID, designating atom type 'mdhd'.

header
Discussion

A MediaHeader data structure, which contains the actual data for this atom.

Parent Atom
'mdia'
Parent atom can contain only one atom of this type.
Programming Info
C interface file: MoviesFormat.h
See Also

For general information about atoms, see Inside QuickTime: QuickTime File Format.

'mdia' Defines the media for a movie track.

struct MediaDirectory {
long size;
long atomType;
MediaHeaderAtom mediaHeader;
HandlerAtom mediaHandler;
MediaInfo mediaInfo;
};

Fields
size
Discussion

The size in bytes of this atom structure.

atomType
Discussion

Constant MediaAID, designating atom type 'mdia'.

mediaHeader
Discussion

A 'mdhd' atom that specifies general characteristics of the media.

mediaHandler
Discussion

A 'hdlr' atom that defines a handler for the media.

mediaInfo
Discussion

A 'minf'[generic] atom structure that contains data to be passed to the media handler.

Parent Atom
'trak'
Parent atom can contain only one atom of this type.
Required Child Atoms
'mdhd'
General characteristics of the media. Only one allowed.
Optional Child Atoms
'hdlr'
The type of media this atom contains. Only one allowed.
'minf'[generic]
Data that is specific to a media handler. Only one allowed.
'udta'
User data atom. Only one allowed.
Discussion

The 'hdlr' atom specifies what type of media this atom contains; for example, video or sound. The content of the 'minf'[generic] atom is specific to the media handler that is to interpret the media.

Programming Info
C interface file: MoviesFormat.h
See Also

See the MediaHeader structure. For general information about atoms, see Inside QuickTime: QuickTime File Format.

'mime'[atom] Defines a graphics export MIME type.

This is a QT leaf atom; it is not declared in the header files. You can create it with QTInsertChild using the following parameters:

Fields
atomType
Discussion

Constant kGraphicsExportMIMEType, designating atom type 'mime'.

data
Discussion

A nonterminated string containing a MIME type.

Parent Atom
'expo'
Parent atom can contain only one atom of this type.
See Also

See the GraphicsImportGetExportImageTypeList, GraphicsImportGetMIMETypeList, and GraphicsExportGetMIMETypeList functions. For general information about atoms, see Inside QuickTime: QuickTime File Format.

'minf'[base] Provides data that is specific to a handler for media other than video or sound.

struct MediaInfo {
long size;
long atomType;
};

Fields
size
Discussion

The size in bytes of this atom structure.

atomType
Discussion

Constant MediaInfoAID, designating atom type 'minf'.

Parent Atom
'mdia'
Parent atom can contain only one atom of this type.
Required Child Atoms
'gmhd'
Generic media information atom. Only one allowed.
'gmin'
Provides data that is specific to a handler for media other than video or sound. Only one allowed.
Discussion

Media information atoms store handler-specific information for the media data that constitutes a track. The media handler uses this information to map from media time to media data. The format and content of media information atoms are dictated by the media handler that is responsible for interpreting the media data stream. Another media handler would not know how to interpret this information.

Programming Info
C interface file: MoviesFormat.h
See Also

This isotope of the 'minf' atom provides data that is specific to a handler for media other than video or sound. Handler-specific data for sound and video are provided by the 'minf'[sound] atom and the 'minf'[video] atom. For general information about atoms, see Inside QuickTime: QuickTime File Format.

'minf'[generic] Provides data that is specific to a handler for media other than video or sound.

struct MediaInfo {
long size;
long atomType;
};

Fields
size
Discussion

The size in bytes of this atom structure.

atomType
Discussion

Constant MediaInfoAID, designating atom type 'minf'.

Parent Atom
'mdia'
Parent atom can contain only one atom of this type.
Required Child Atoms
'gmhd'
Generic media information atom. Only one allowed.
'hdlr'
The type of media this atom contains. Only one allowed.
Optional Child Atoms
'dinf'
Specifies where media data is stored. Only one allowed.
'stbl'
Contains information for converting from media time to sample number to sample location and indicates how to interpret samples and chunks. Only one allowed.
Discussion

Media information atoms store handler-specific information for the media data that constitutes a track. The media handler uses this information to map from media time to media data. The format and content of media information atoms are dictated by the media handler that is responsible for interpreting the media data stream. Another media handler would not know how to interpret this information.

Programming Info
C interface file: MoviesFormat.h
See Also

This isotope of the 'minf' atom provides data that is specific to a handler for media other than video or sound. Handler-specific data for sound and video are provided by the 'minf'[sound] atom and the 'minf'[video] atom. For general information about atoms, see Inside QuickTime: QuickTime File Format.

'minf'[sound] Sound media information atom.

struct MediaInfo {
long size;
long atomType;
};

Fields
size
Discussion

The size in bytes of this atom structure.

atomType
Discussion

Constant MediaInfoAID, designating atom type 'minf'.

Parent Atom
'mdia'
Parent atom can contain only one atom of this type.
Required Child Atoms
'smhd'
Contains sound stereo balance information. Only one allowed.
'hdlr'
The type of media this atom contains. Only one allowed.
Optional Child Atoms
'dinf'
Specifies where media data is stored. Only one allowed.
'stbl'
Contains information for converting from media time to sample number to sample location and indicates how to interpret samples and chunks. Only one allowed.
Discussion

Media information atoms store handler-specific information for the media data that constitutes a track. The media handler uses this information to map from media time to media data. The format and content of media information atoms are dictated by the media handler that is responsible for interpreting the media data stream. Another media handler would not know how to interpret this information.

Programming Info
C interface file: MoviesFormat.h
See Also

This isotope of the 'minf' atom provides handler-specific data for sound. Handler-specific data for video is provided by the the 'minf'[video] atom. For general information about atoms, see Inside QuickTime: QuickTime File Format.

'minf'[video] Video media information atom.

struct MediaInfo {
long size;
long atomType;
};

Fields
size
Discussion

The size in bytes of this atom structure.

atomType
Discussion

Constant MediaInfoAID, designating atom type 'minf'.

Parent Atom
'mdia'
Parent atom can contain only one atom of this type.
Required Child Atoms
'vmhd'[media]
Stores handler-specific information for video media in a track. Only one allowed.
'hdlr'
The type of media this atom contains. Only one allowed.
Optional Child Atoms
'dinf'
Specifies where media data is stored. Only one allowed.
'stbl'
Contains information for converting from media time to sample number to sample location and indicates how to interpret samples and chunks. Only one allowed.
Discussion

Media information atoms store handler-specific information for the media data that constitutes a track. The media handler uses this information to map from media time to media data. The format and content of media information atoms are dictated by the media handler that is responsible for interpreting the media data stream. Another media handler would not know how to interpret this information.

Programming Info
C interface file: MoviesFormat.h
See Also

This isotope of the 'minf' atom provides handler-specific data for video. Handler-specific data for sound is provided by the 'minf'[sound] atom. For general information about atoms, see Inside QuickTime: QuickTime File Format.

'moov' Contains the top-level atoms that constitute a movie.

struct MovieDirectory {
long size;
long atomType;
MovieHeaderAtom header;
ClippingAtom movieClip;
TrackDirectoryEntry track[1];
UserDataAtom userData;
};

Fields
size
Discussion

The size in bytes of this atom structure.

atomType
Discussion

Constant MovieAID, designating atom type 'moov'.

header
Discussion

A 'mvhd' atom that specifies the general characteristics of the movie.

movieClip
Discussion

A 'clip' atom that defines the clipping region for the movie.

track
Discussion

An array of one or more TrackDirectoryEntry data structures, each of which includes a 'trak' atom that defines a track in the movie.

userData
Discussion

A 'udta' atom, which contains user data.

Required Child Atoms
'mvhd'
Specifies the general characteristics of a movie. Only one allowed.
Optional Child Atoms
'clip'
Defines the clipping region for the movie. Only one allowed.
'trak'
Defines a single track of the movie. Any number allowed.
'udta'
User data atom. Only one allowed.
'ctab'
Color table atom. Only one allowed.
'ptv '
Defines a movie's full screen mode.
Discussion

You use movie atoms to specify the information that defines a movie; that is, the information that allows your application to understand the data that is stored in the movie data atom. The movie atom contains the movie header atom, which defines the time scale and duration information for the entire movie, as well as its display characteristics. In addition, the movie atom contains each track in the movie.

Programming Info
C interface file: MoviesFormat.h
See Also

See the MovieHeader structure. For general information about atoms, see Inside QuickTime: QuickTime File Format.

'mvhd' Specifies the characteristics of an entire movie.

struct MovieHeaderAtom {
long size;
long atomType;
MovieHeader header;
};

Fields
size
Discussion

The size in bytes of this atom structure.

atomType
Discussion

Constant MovieHeaderAID, designating atom type 'mvhd'.

header
Discussion

A MovieHeader data structure, which contains the actual data for this atom.

Parent Atom
'moov'
Parent atom can contain only one atom of this type.
Discussion

You use the movie header atom to specify the characteristics of an entire QuickTime movie. The data contained in this atom defines characteristics of the entire QuickTime movie, such as time scale and duration.

Programming Info
C interface file: MoviesFormat.h
See Also

For general information about atoms, see Inside QuickTime: QuickTime File Format.

'name'[sprite] A sprite name atom.

This is a QT leaf atom; it is not declared in the header files. You can create it with QTInsertChild using the following parameters:

Fields
atomType
Discussion

Constant kSpriteNameAtomType, designating atom type 'name'.

data
Discussion

One or more ASCII characters comprising the sprite's name.

Parent Atom
'sprt'
Parent atom can contain only one atom of this type.
See Also

For general information about atoms, see Inside QuickTime: QuickTime File Format.

'name'[userdata] User data list entry atom: name of object.

struct MoviesUserData {
long size;
long udType;
char data[1];
};

Fields
size
Discussion

The size in bytes of this atom structure.

udType
Discussion

Constant kUserDataName, designating atom type 'name'.

data
Discussion

A name string.

Parent Atom
'udta'
Parent atom can contain only one atom of this type.
Programming Info
C interface file: MoviesFormat.h
See Also

See the MoviesUserData structure. For general information about atoms, see Inside QuickTime: QuickTime File Format.

'ndhd' Node header atom.

This is a QT leaf atom; it is not declared in the header files. You can create it with QTInsertChild using the following parameters:

Fields
atomType
Discussion

Constant kQTVRNodeHeaderAtomType, designating atom type 'ndhd'.

data
Discussion

Node header information.

See Also

For general information about atoms, see Inside QuickTime: QuickTime File Format.

'nloc' QTVR node location atom.

This is a QT leaf atom; it is not declared in the header files. You can create it with QTInsertChild using the following parameters:

Fields
atomType
Discussion

Constant kQTVRNodeLocationAtomType, designating atom type 'nloc'.

data
Discussion

Node location.

Parent Atom
'vrni'
Parent atom can contain only one atom of this type.
See Also

For general information about atoms, see Inside QuickTime: QuickTime File Format.

'nump' Total number of network packets that will be sent.

This is a QT leaf atom; it is not declared in the header files. You can create it with QTInsertChild using the following parameters:

Fields
atomType
Discussion

Value is 'nump'.

data
Discussion

8 bytes.

Parent Atom
'hinf'
Parent atom can contain only one atom of this type.
See Also

For general information about atoms, see Inside QuickTime: QuickTime File Format.

'obid' Object ID atom.

This is a QT leaf atom; it is not declared in the header files. You can create it with QTInsertChild using the following parameters:

Fields
atomType
Discussion

Constant kTrackModifierObjectID, designating atom type 'obid'.

data
Discussion

The object ID.

Parent Atom
' in'
Parent atom can contain only one atom of this type.
See Also

For general information about atoms, see Inside QuickTime: QuickTime File Format.

'payt' Payload type atom.

This is a QT leaf atom; it is not declared in the header files. You can create it with QTInsertChild using the following parameters:

Fields
atomType
Discussion

Value is 'payt'.

data
Discussion

Payload type, which includes payload number (32-bits) followed by an RTP map payload string (a Pascal string).

Parent Atom
'hinf'
Parent atom can contain only one atom of this type.
See Also

For general information about atoms, see Inside QuickTime: QuickTime File Format.

'pdat' Panorama sample atom.

This is a QT leaf atom; it is not declared in the header files. You can create it with QTInsertChild using the following parameters:

Fields
atomType
Discussion

Constant kQTVRPanoSampleDataAtomType, designating atom type 'pdat'.

data
Discussion

A panorama sample.

See Also

For general information about atoms, see Inside QuickTime: QuickTime File Format.

'pmax' Largest packet, in bytes; includes 12-byte RTP header.

This is a QT leaf atom; it is not declared in the header files. You can create it with QTInsertChild using the following parameters:

Fields
atomType
Discussion

Value is 'pmax'.

data
Discussion

4 bytes.

Parent Atom
'hinf'
Parent atom can contain only one atom of this type.
See Also

For general information about atoms, see Inside QuickTime: QuickTime File Format.

'pnot' Reference to movie preview data.

This is a QT leaf atom; it is not declared in the header files. You can create it with QTInsertChild using the following parameters:

Fields
atomType
Discussion

Constant ShowFilePreviewComponentType, designating atom type 'pnot'.

data
Discussion

Reference to a movie preview.

See Also

For general information about atoms, see Inside QuickTime: QuickTime File Format.

'ptv ' Defines a movie's full screen mode.

This is a classic atom; you can access its information by calculating offsets.

Fields
size
Discussion

Value is 0x0000000C.

atomType
Discussion

Value is 'ptv '.

Parent Atom
'moov'
Contains the top-level atoms that constitute a movie.
Data offsets
0x0000
Display size: a 16-bit big-endian integer (see below) indicating the display size for the movie.
0x0002
Reserved: set to 0.
0x0004
Reserved: set to 0.
0x0006
Slide show: an 8-bit Boolean whose value is 1 for a slide show. In slide show mode, the movie advances one frame each time the right-arrow key is pressed. Audio is muted.
0x0007
Play on open: an 8-bit boolean whose value is normally 1, indicating that the movie should play when opened. Since there is no visible controller in full-screen mode, applications should always set this field to 1 to prevent user confusion.
Display size constants
0x00000
The movie should be played at its normal size.
0x0001
The movie should be played at double size.
0x0002
The movie should be played at half size.
0x0003
The movie should be scaled to fill the screen.
0x0004
The movie should be played at its current size. This value is normally used when the 'ptv ' atom is inserted transiently and the movie has been temporarily resized.
See Also

For general information about atoms, see Inside QuickTime: QuickTime File Format.

'qdrg' QuickDraw region atom.

This is a QT leaf atom; it is not declared in the header files. You can create it with QTInsertChild using the following parameters:

Fields
atomType
Discussion

Constant kTweenRegionData, designating atom type 'qdrg'.

data
Discussion

Two Rect structures and a MacRegion structure.

Discussion

This atom's ID must be 1.

See Also

See the TweenerInitialize function. For general information about atoms, see Inside QuickTime: QuickTime File Format.

'rdrf' Provides a reference to an alternate movie.

This is a QT leaf atom; it is not declared in the header files. You can create it with QTInsertChild using the following parameters:

Fields
atomType
Discussion

Constant ReferenceMovieDataRefAID, designating atom type 'rdrf'.

data
Discussion

A ReferenceMovieDataRefRecord data structure. The alternate movie referenced by this structure is the movie associated with the parent 'rmda' atom.

Parent Atom
'rmda'
Parent atom can contain only one atom of this type.
Discussion

Alias data references are the contents of AliasRecord structures. The QuickTime plug-in is smart enough to convert a relative alias to a relative URL. To designate the anchor file for a relative alias, pass the FSSpec structure that specifies the file you are creating. You can pass absolute or relative URLs; if the movie is loaded from the desktop, QuickTime will convert a relative URL into a relative alias.

See Also

For general information about atoms, see Inside QuickTime: QuickTime File Format.

'reso' Pixmap resolution atom.

This is a QT leaf atom; it is not declared in the header files. You can create it with QTInsertChild using the following parameters:

Fields
atomType
Discussion

Constant kQTResolutionSettings, designating atom type 'reso'.

data
Discussion

A QTResolutionSettings structure.

Parent Atom
'vide'
Parent atom can contain only one atom of this type.
Discussion

This atom specifies the resolution for the PixMap structure passed to the compressor.

See Also

For general information about atoms, see Inside QuickTime: QuickTime File Format.

'rmcd' Provides component availability information for selecting an alternate movie.

This is a QT leaf atom; it is not declared in the header files. You can create it with QTInsertChild using the following parameters:

Fields
atomType
Discussion

Constant ReferenceMovieComponentCheckAID, designating atom type 'rmcd'.

data
Discussion

A QTAltComponentCheckRecord data structure.

Parent Atom
'rmda'
Parent atom can contain any number of atoms of this type.
See Also

See the QTAltComponentCheckRecord structure. For general information about atoms, see Inside QuickTime: QuickTime File Format.

'rmcs' Provides CPU speed information for selecting an alternate movie.

This is a QT atom; it is not declared in the header files. You can create it with QTInsertChild using the following parameters:

Fields
atomType
Discussion

Constant ReferenceMovieCPURatingAID, designating atom type 'rmcs'.

data
Discussion

A QTAltCPURatingRecord data structure.

Parent Atom
'rmda'
Parent atom can contain only one atom of this type.
See Also

See the QTAltCPURatingRecord structure. For general information about atoms, see Inside QuickTime: QuickTime File Format.

'rmda' Provides criteria for selecting an alternate movie.

This is a QT atom; it is not declared in the header files. You can create it with QTInsertChild using the following parameter:

Fields
atomType
Discussion

Constant ReferenceMovieDescriptorAID, designating atom type 'rmda'.

Parent Atom
'rmra'
Parent atom can contain only one atom of this type.
Required Child Atoms
'rdrf'
A reference to an alternate movie. Only one allowed.
Optional Child Atoms
'rmdr'
Data rate information for selecting an alternate movie. Only one allowed.
'rmvc'
Version criteria for selecting an alternate movie. Multiples allowed.
'rmcd'
Component availability information for selecting an alternate movie. Multiples allowed.
'rmqu'
Playback quality information for selecting an alternate movie. Only one allowed.
'rmla'
Language information for selecting an alternate movie. Only one allowed.
'rmcs'
CPU speed information for selecting an alternate movie. Only one allowed.
Discussion

The 'rdrf' atom contains a ReferenceMovieDataRefRecord, which designates an alternate movie. The 'rmda' atom's optional atoms help QuickTime decide whether or not to run that movie. If multiple 'rmvc' or 'rmcd' atoms are present, all their criteria must be satisfied for the movie to play.

See Also

See the ReferenceMovieDataRefRecord structure. For general information about atoms, see Inside QuickTime: QuickTime File Format.

'rmdr' Provides data rate information for selecting an alternate movie.

This is a QT leaf atom; it is not declared in the header files. You can create it with QTInsertChild using the following parameters:

Fields
atomType
Discussion

Constant ReferenceMovieDataRateAID, designating atom type 'rmdr'.

data
Discussion

A QTAltDataRateRecord data structure.

Parent Atom
'rmda'
Parent atom can contain only one atom of this type.
See Also

For general information about atoms, see Inside QuickTime: QuickTime File Format.

'rmla' Provides language information for selecting an alternate movie.

This is a QT leaf atom; it is not declared in the header files. You can create it with QTInsertChild using the following parameters:

Fields
atomType
Discussion

Constant ReferenceMovieLanguageAID, designating atom type 'rmla'.

data
Discussion

A QTAltLanguageRecord structure.

Parent Atom
'rmda'
Parent atom can contain only one atom of this type.
See Also

For general information about atoms, see Inside QuickTime: QuickTime File Format.

'rmqu' Provides playback quality information for selecting an alternate movie.

This is a QT leaf atom; it is not declared in the header files. You can create it with QTInsertChild using the following parameters:

Fields
atomType
Discussion

Constant ReferenceMovieQualityAID, designating atom type 'rmqu'.

data
Discussion

A quality value of type SInt32. Higher quality values are selected over lower quality values.

Parent Atom
'rmda'
Parent atom can contain only one atom of this type.
Discussion

If the criteria established by the 'rmdr', 'rmvc', and 'rmcd' atoms are equally satisfied by two or more alternate movies, the one with the highest quality value will be selected.

See Also

For general information about atoms, see Inside QuickTime: QuickTime File Format.

'rmra' Designates a reference movie.

This is a QT atom; it is not declared in the header files. You can create it with QTInsertChild using the following parameter:

Fields
atomType
Discussion

Constant ReferenceMovieRecordAID, designating atom type 'rmra'.

Parent Atom
'moov'
Parent atom can contain only one atom of this type.
Required Child Atoms
'rmda'
Provides criteria for selecting an alternate movie. Only one allowed.
Discussion

You insert an 'rmra' atom in a 'moov' atom to create a reference movie. Each 'rmda' atom in the 'rmra' atom designates an alternate movie.

See Also

For general information about atoms, see Inside QuickTime: QuickTime File Format.

'rmvc' Provides version criteria for selecting an alternate movie.

This is a QT leaf atom; it is not declared in the header files. You can create it with QTInsertChild using the following parameters:

Fields
atomType
Discussion

Constant ReferenceMovieVersionCheckAID, designating atom type 'rmvc'.

data
Discussion

A QTAltVersionCheckRecord data structure.

Parent Atom
'rmda'
Parent atom can contain any number of atoms of this type.
Discussion

This optional atom in a 'rmda' atom lets you demand minimum product version criteria for selecting an alternate movie. For example, a movie that needs QuickTime VR 2.1 or later could require a Gestalt 'qtvv' value of 0x02100000 or higher.

See Also

For general information about atoms, see Inside QuickTime: QuickTime File Format.

'scpt' Transcript track reference type atom.

This is a QT leaf atom; it is not declared in the header files. You can create it with QTInsertChild using the following parameters:

Fields
atomType
Discussion

Value is 'scpt'.

data
Discussion

A list of track ID values (32-bit integers) specifying the related tracks. Note that a track ID value can be set to 0 to indicate an unused entry in the atom. Doing this can be more convenient than deleting the reference.

Parent Atom
'tref'
Parent atom can contain only one atom of this type.
See Also

For general information about atoms, see Inside QuickTime: QuickTime File Format.

'sdp ' SDP text for a hint track.

This is a QT leaf atom; it is not declared in the header files. You can create it with QTInsertChild using the following parameters:

Fields
atomType
Discussion

Value is 'sdp '. The fourth character is a space.

data
Discussion

SDP text.

See Also

For general information about atoms, see Inside QuickTime: QuickTime File Format.

'sean' The outermost atom container, of which all other atoms are children.

This is a QT container atom; it is not declared in the header files. You can create it with QTNewAtomContainer, using the following parameter:

Fields
atomData
Discussion

A pointer to a memory location that will hold the new atom.

Discussion

After creating a 'sean' atom, you can populate it with other atoms by using QTInsertChild.

See Also

For general information about atoms, see Inside QuickTime: QuickTime File Format.

'SelO' User data list entry atom: play selection only.

struct MoviesUserData {
long size;
long udType;
char data[1];
};

Fields
size
Discussion

The size in bytes of this atom structure.

udType
Discussion

Constant 'SelO'.

data
Discussion

A byte indicating that only the selected area of the movie should be played.

Parent Atom
'udta'
Parent atom can contain only one atom of this type.
Programming Info
C interface file: MoviesFormat.h
See Also

See the MoviesUserData function. For general information about atoms, see Inside QuickTime: QuickTime File Format.

'skip' Unused space available in the file.

This is a QT leaf atom; it is not declared in the header files. You can create it with QTInsertChild using the following parameters:

Fields
atomType
Discussion

Constant SkipAtomType, designating atom type 'skip'.

data
Discussion

Any number of bytes of free space.

See Also

For general information about atoms, see Inside QuickTime: QuickTime File Format.

'smhd' Contains sound stereo balance information.

struct SoundMediaInfoHeaderAtom {
long size;
long atomType;
SoundMediaInfoHeader smiHeader;
};

Fields
size
Discussion

The size in bytes of this atom structure.

atomType
Discussion

Constant SoundMediaInfoHeaderAID, designating atom type 'smhd'.

smiHeader
Discussion

A SoundMediaInfoHeader data structure, which contains the actual data for this atom.

Discussion

The SoundMediaInfoHeader data structure currently contains only stereo balance information.

Programming Info
C interface file: MoviesFormat.h
See Also

For the structure that contains this atom, see 'minf'[sound]. For general information about atoms, see Inside QuickTime: QuickTime File Format.

'sprt' A key frame sprite definition.

This is a QT leaf atom; it is not declared in the header files. You can create it with QTInsertChild using the following parameters:

Fields
atomType
Discussion

Constant kSpriteAtomType, designating atom type 'sprt'.

data
Discussion

A list of sprite property constants (see below).

Sprite property constants
kSpritePropertyMatrix
(Value is 1). Describes the sprite's location and scaling within its sprite world or sprite track. By modifying a sprite's matrix, you can modify the sprite's location so that it appears to move in a smooth path on the screen or so that it jumps from one place to another. You can modify a sprite's size, so that it shrinks, grows, or stretches. Depending on which image compressor is used to create the sprite images, other transformations, such as rotation, may be supported as well. Translation-only matrixes provide the best performance.
kSpritePropertyVisible
(Value is 4). Specifies whether or not the sprite is visible. To make a sprite visible, you set the sprite's visible property to true.
kSpritePropertyLayer
(Value is 5). Contains a 16-bit integer value specifying the layer into which the sprite is to be drawn. Sprites with lower layer numbers appear in front of sprites with higher layer numbers. To designate a sprite as a background sprite, you should assign it the special layer number kBackgroundSpriteLayerNum.
kSpritePropertyGraphicsMode
(Value is 6). Specifies a graphics mode and blend color that indicates how to blend a sprite with any sprites behind it and with the background. To set a sprite's graphics mode, you call SetSpriteProperty, passing a pointer to a ModifierTrackGraphicsModeRecord structure.
kSpritePropertyActionHandlingSpriteID
(Value is 8). Specifies another sprite by ID that delegates QT events.
kSpritePropertyImageIndex
(Value is 100). Contains the atom ID of the sprite's image atom.
kSpriteUsesImageIDsAtomType
(Value is 'uses'). Lets a sprite specify the subset of images that kSpritePropertyImageIndex can refer to.
Parent Atom
'stss'
Parent atom can contain only one atom of this type.
Discussion

Sprite atoms should have ID numbers start at 1 and count consecutively upward.

See Also

For general information about atoms, see Inside QuickTime: QuickTime File Format.

'sptl' Specifies which graphics export compressor to use, its depth, and the spatial quality.

This is a QT leaf atom; it is not declared in the header files. You can create it with QTInsertChild using the following parameters:

Fields
size
Discussion

The size in bytes of this atom structure.

atomType
Discussion

Constant scSpatialSettingsType, designating atom type 'sptl'.

data
Discussion

A pointer to SCSpatialSettings structure.

See Also

See the GraphicsExportCanUseCompressor function. For general information about atoms, see Inside QuickTime: QuickTime File Format.

'ssrc' Nonprimary source track reference type atom.

This is a QT leaf atom; it is not declared in the header files. You can create it with QTInsertChild using the following parameters:

Fields
atomType
Discussion

Constant kTrackModifierReference, designating atom type 'ssrc'.

data
Discussion

A list of track ID values (32-bit integers) specifying the related tracks. Note that a track ID value can be set to 0 to indicate an unused entry in the atom. Doing this can be more convenient than deleting the reference.

Parent Atom
'tref'
Parent atom can contain only one atom of this type.
See Also

For general information about atoms, see Inside QuickTime: QuickTime File Format.

'sstr' Specifies the ID of a string variable, contained in a sprite track, to display in the status area of the browser.

This is a QT container atom; it is not declared in the header files. You can create it with QTNewAtomContainer and insert it with QTInsertChild, using the following parameter:

Fields
atomType
Discussion

Value is 'sstr'.

Parent Atom
'beha'
Defines sprite behavior.
See Also

For general information about atoms, see Inside QuickTime: QuickTime File Format.

'stbl' Contains information for converting from media time to sample number to sample location and indicates how to interpret samples and chunks.

struct SampleTableAtom {
long size;
long atomType;
SampleDescriptionAtom sampleDescription;
TimeToSampleNumAtom timeToSampleNum;
SampleToChunkAtom sampleToChunk;
SyncSampleAtom syncSample;
SampleSizeAtom sampleSize;
ChunkOffsetAtom chunkOffset;
ShadowSyncAtom shadowSync;
};

Fields
size
Discussion

The size in bytes of this atom structure.

atomType
Discussion

Constant SampleTableAID, designating atom type 'stbl'.

sampleDescription
Discussion

A 'stsd' atom, which contains information required to decode the samples in the media.

timeToSampleNum
Discussion

A 'stts' atom that relates sample numbers to sample durations.

sampleToChunk
Discussion

A 'stsc' atom that maps sample numbers to chunk numbers.

syncSample
Discussion

A 'stss' atom that identifies the key frames in the media.

sampleSize
Discussion

A 'stsz' atom, which identifies the size of each sample in the media.

chunkOffset
Discussion

A 'stco' atom that identifies the location of each data chunk in the media.

shadowSync
Discussion

A 'stsh' atom, which lists self-contained sync samples that are alternates for existing frame difference samples. This field may be omitted.

Discussion

This atom contains the information you need to find a sample number based on a time and to find the sample's location based on the sample number. Samples are organized into chunks, containing one or more samples. This atom contains the information you need to find out which chunk holds a given sample, where that chunk begins, and where in that chunk you can find the sample.

Programming Info
C interface file: MoviesFormat.h
See Also

For the atoms that may contain this atom, see 'minf'[generic], 'minf'[sound], and 'minf'[video]. For general information about atoms, see Inside QuickTime: QuickTime File Format.

'stco' Identifies the location of each chunk of data in the media's data stream.

struct ChunkOffsetAtom {
long size;
long atomType;
long flags;
long numEntries;
long chunkOffsetTable[1];
};

Fields
size
Discussion

The size in bytes of this atom structure.

atomType
Discussion

Constant STChunkOffsetAID, designating atom type 'stco'.

flags
Discussion

One byte of version information followed by three bytes of flags. The flags bytes are not currently used.

numEntries
Discussion

The number of entries in chunkOffsetTable.

chunkOffsetTable
Discussion

An array of chunk offset values.

Discussion

A chunk is a collection of data samples in a media that allows optimized data access. A chunk may contain one or more samples. Chunks in a media may have different sizes, and the samples within a chunk may have different sizes.

Programming Info
C interface file: MoviesFormat.h
See Also

For the structure that contains this atom, see 'stbl'. For general information about atoms, see Inside QuickTime: QuickTime File Format.

'strt' Defines the starting offset of hypertext in a text stream.

This is a QT leaf atom; it is not declared in the header files. You can create it with QTInsertChild using the following parameters:

Fields
atomType
Discussion

Value is 'strt'.

data
Discussion

The starting offset of hypertext.

Parent Atom
'htxt'
Parent atom can contain only one atom of this type.
See Also

For general information about atoms, see Inside QuickTime: QuickTime File Format.

'strv' Contains a string variable for a sprite.

This is a QT container atom; it is not declared in the header files. You can create it with QTNewAtomContainer and insert it with QTInsertChild, using the following parameter:

Fields
atomType
Discussion

Value is 'strv'.

Parent Atom
'vars'
Contains variables for a sprite.
See Also

For general information about atoms, see Inside QuickTime: QuickTime File Format.

'stsc' Maps sample numbers to chunk numbers.

struct SampleToChunkAtom {
long size;
long atomType;
long flags;
long numEntries;
SampleToChunk sampleToChunkTable[1];
};

Fields
size
Discussion

The size in bytes of this atom structure.

atomType
Discussion

Constant STSampleToChunkAID, designating atom type 'stsc'.

flags
Discussion

One byte of version information followed by three bytes of flags. The flags bytes are not currently used.

numEntries
Discussion

The number of entries in sampleToChunkTable.

sampleToChunkTable
Discussion

An array of SampleToChunk data structures, which contain the actual data for this atom.

Discussion

A chunk is a collection of data samples in a media that allows optimized data access. A chunk may contain one or more samples. Chunks in a media may have different sizes, and the samples within a chunk may have different sizes.

Programming Info
C interface file: MoviesFormat.h
See Also

For the structure that contains this atom, see 'stbl'. For general information about atoms, see Inside QuickTime: QuickTime File Format.

'stsd' Holds one or more sample description structures.

struct SampleDescriptionAtom {
long size;
long atomType;
long flags;
long numEntries;
SampleDescription sampleDescTable[1];
};

Fields
size
Discussion

The size in bytes of this atom structure.

atomType
Discussion

Constant STSampleDescAID, designating atom type 'stsd'.

flags
Discussion

One byte of version information followed by three bytes of flags. The flags bytes are not currently used.

numEntries
Discussion

Number of entries in sampleDescTable.

sampleDescTable
Discussion

An array of SampleDescription data structures, which contain the actual data for this atom.

Discussion

In QuickTime streaming, this atom describes the data format of the hint samples and contains track-level information, such as the RTP timescale for a track.

Programming Info
C interface file: MoviesFormat.h
See Also

For the structure that contains this atom, see 'stbl'. For general information about atoms, see Inside QuickTime: QuickTime File Format.

'stsh' Lists self-contained sync samples that are alternates for existing frame difference samples.

struct ShadowSyncAtom {
long size;
long atomType;
long flags;
long numEntries;
ShadowSync shadowSyncTable[1];
};

Fields
size
Discussion

The size in bytes of this atom structure.

atomType
Discussion

Constant STShadowSyncAID, designating atom type 'stsh'.

flags
Discussion

One byte of version information followed by three bytes of flags. The flags bytes are not currently used.

numEntries
Discussion

The number of entries in shadowSyncTable.

shadowSyncTable
Discussion

An array of ShadowSync data structures, which contain the actual data for this atom.

Discussion

Shadow sync atoms are used to optimize random access operations on a movie, thereby enhancing playback performance.

Programming Info
C interface file: MoviesFormat.h
See Also

For general information about atoms, see Inside QuickTime: QuickTime File Format.

'stss' Identifies the key frames in a media.

struct SyncSampleAtom {
long size;
long atomType;
long flags;
long numEntries;
long syncSampleTable[1];
};

Fields
size
Discussion

The size in bytes of this atom structure.

atomType
Discussion

Constant STSyncSampleAID, designating atom type 'stss'.

flags
Discussion

Flags (currently not used).

numEntries
Discussion

The number of entries in syncSampleTable.

syncSampleTable
Discussion

An array of physical sample numbers, each of which identifies a key frame in the media.

Discussion

In a media that contains compressed data, key frames define starting points for portions of a temporally compressed sequence. Each key frame is independent of the preceding frames. Subsequent frames may depend on the key frame.

Programming Info
C interface file: MoviesFormat.h
See Also

For the structure that contains this atom, see 'stbl'. For general information about atoms, see Inside QuickTime: QuickTime File Format.

'stsz' Identifies the size of each sample in a media.

struct SampleSizeAtom {
long size;
long atomType;
long flags;
long sampleSize;
long numEntries;
long sampleSizeTable[1];
};

Fields
size
Discussion

The size in bytes of this atom structure.

atomType
Discussion

Constant STSampleSizeAID, designating atom type 'stsz'.

flags
Discussion

One byte of version information followed by three bytes of flags. The flags bytes are not currently used.

sampleSize
Discussion

The number of bytes in the samples. If all the samples are the same size, sampleSize indicates the size of all the samples. If sampleSize is set to 0, then the samples have different sizes, and those sizes are stored in sampleSizeTable.

numEntries
Discussion

The number of entries in sampleSizeTable.

sampleSizeTable
Discussion

An array of numbers, one for every sample. This field is indexed by sample number; the first entry corresponds to the first sample, the second to the second sample, and so on.

Programming Info
C interface file: MoviesFormat.h
See Also

For the structure that contains this atom, see 'stbl'. For general information about atoms, see Inside QuickTime: QuickTime File Format.

'stts' Holds one or more structures that relate sample numbers to sample durations.

struct TimeToSampleNumAtom {
long size;
long atomType;
long flags;
long numEntries;
TimeToSampleNum timeToSampleNumTable[1];
};

Fields
size
Discussion

The size in bytes of this atom structure.

atomType
Discussion

Constant STTimeToSampAID, designating atom type 'stts'.

flags
Discussion

One byte of version information followed by three bytes of flags. The flags bytes are not currently used.

numEntries
Discussion

The number of entries in timeToSampleNumTable.

timeToSampleNumTable
Discussion

An array of TimeToSampleNum data structures, each of which maps a sample number to its sample duration.

Discussion

Entries in timeToSampleNumTable collect samples according to their order in the media and their duration. If consecutive samples have the same duration, a single table entry may be used to define more than one sample. In these cases, the count field indicates the number of consecutive samples that have the same duration. For example, if a video media had a constant frame rate, timeToSampleNumTable would have one entry.

Programming Info
C interface file: MoviesFormat.h
See Also

For the structure that contains this atom, see 'stbl'. For general information about atoms, see Inside QuickTime: QuickTime File Format.

'sync' Synchronization track reference type atom.

This is a QT leaf atom; it is not declared in the header files. You can create it with QTInsertChild using the following parameters:

Fields
atomType
Discussion

Value is 'sync'.

data
Discussion

A list of track ID values (32-bit integers) specifying the related tracks. Note that a track ID value can be set to 0 to indicate an unused entry in the atom. Doing this can be more convenient than deleting the reference.

Parent Atom
'tref'
Parent atom can contain only one atom of this type.
See Also

For general information about atoms, see Inside QuickTime: QuickTime File Format.

'tbox' Defines a text box rectangle.

struct TextBoxAtom {
long size;
long atomType;
Rect textBox;
};

Fields
size
Discussion

The size in bytes of this atom structure.

atomType
Discussion

Value is 'tbox'.

textBox
Discussion

A new text box rectangle, which overrides the rectangle defined by the defaultTextBox constant.

Discussion

This is a classic atom; you can access its information by calculating offsets.

Programming Info
C interface file: MoviesFormat.h
See Also

For general information about atoms, see Inside QuickTime: QuickTime File Format.

'tcmi' Time code media information atom.

This is a QT leaf atom; it is not declared in the header files. You can create it with QTInsertChild using the following parameters:

Fields
atomType
Discussion

Value is 'tcmi'.

data
Discussion

Time code media information.

Parent Atom
'minf'[video]
Parent atom can contain only one atom of this type.
See Also

For general information about atoms, see Inside QuickTime: QuickTime File Format.

'tkhd' Specifies the characteristics of a track in a movie.

struct TrackHeaderAtom {
long size;
long atomType;
TrackHeader header;
};

Fields
size
Discussion

The size in bytes of this atom structure.

atomType
Discussion

Constant TrackHeaderAID, designating atom type 'tkhd'.

header
Discussion

A TrackHeader structure that contains the actual data for this atom.

Parent Atom
'trak'
Parent atom can contain only one atom of this type.
Programming Info
C interface file: MoviesFormat.h
See Also

For general information about atoms, see Inside QuickTime: QuickTime File Format.

'tmax' Largest relative transmission time, in milliseconds.

This is a QT leaf atom; it is not declared in the header files. You can create it with QTInsertChild using the following parameters:

Fields
atomType
Discussion

Value is 'tmax'.

data
Discussion

4 bytes.

Parent Atom
'hinf'
Parent atom can contain only one atom of this type.
See Also

For general information about atoms, see Inside QuickTime: QuickTime File Format.

'tmcd' Time code track reference type atom.

This is a QT leaf atom; it is not declared in the header files. You can create it with QTInsertChild using the following parameters:

Fields
atomType
Discussion

Constant TimeCodeMediaType, designating atom type 'tmcd'.

data
Discussion

A list of track ID values (32-bit integers) specifying the related tracks. Note that a track ID value can be set to 0 to indicate an unused entry in the atom. Doing this can be more convenient than deleting the reference.

Parent Atom
'tref'
Parent atom can contain only one atom of this type.
See Also

See the TimeCodeDescription structure. For general information about atoms, see Inside QuickTime: QuickTime File Format.

'tmin' Smallest relative transmission time, in milliseconds.

This is a QT leaf atom; it is not declared in the header files. You can create it with QTInsertChild using the following parameters:

Fields
atomType
Discussion

Value is 'tmin'.

data
Discussion

4 bytes.

Parent Atom
'hinf'
Parent atom can contain only one atom of this type.
See Also

For general information about atoms, see Inside QuickTime: QuickTime File Format.

'tpyl' Total number of bytes that will be sent, not including 12-byte RTP headers.

This is a QT leaf atom; it is not declared in the header files. You can create it with QTInsertChild using the following parameters:

Fields
atomType
Discussion

Value is 'tpyl'.

data
Discussion

8 bytes.

Parent Atom
'hinf'
Parent atom can contain only one atom of this type.
See Also

For general information about atoms, see Inside QuickTime: QuickTime File Format.

'trak' Defines a single track of a movie.

struct TrackDirectory {
long size;
long atomType;
TrackHeaderAtom trackHeader;
ClippingAtom trackClip;
EditsAtom edits;
MediaDirectory media;
UserDataAtom userData;
};

Fields
size
Discussion

The size in bytes of this atom structure.

atomType
Discussion

Constant TrackAID, designating atom type 'trak'.

trackHeader
Discussion

A 'tkhd' atom, which specifies general characteristics of the track.

trackClip
Discussion

A 'clip' atom, which defines the track's clipping region.

edits
Discussion

An 'edts' atom, which defines the portions of the track's media that are going into the track.

media
Discussion

A 'mdia' atom structure that defines the media for the track.

userData
Discussion

A 'udta' atom that contains user data.

Parent Atom
'moov'
Parent atom can contain any number of atoms of this type.
Required Child Atoms
'tkhd'
Specifies general characteristics of the track. Only one allowed.
'mdia'
The media for the track. Only one allowed.
Optional Child Atoms
'clip'
Defines the clipping region for the track. Only one allowed.
'matt'
Defines a matte for a track's media. Only one allowed.
'edts'
Defines the portions of the track's media that are going into the track. Only one allowed.
'tref'
Track reference atom. Only one allowed.
'load'
Contains preloading information for a track. Only one allowed.
'imap'
An input map. Only one allowed.
'udta'
User data atom. Only one allowed.
Discussion

A movie may consist of one or more tracks. Each track is independent of the other tracks in the movie and carries its own temporal and spatial information. Each track atom contains an associated media atom. Note that there must be at least one media track within a QuickTime movie. All media tracks that are present must remain in the movie, even if the media data within them is not referenced by the hint tracks. After deleting all hint tracks, the entire unhinted movie must remain.

Programming Info
C interface file: MoviesFormat.h
See Also

See the TrackDirectoryEntry structure. For general information about atoms, see Inside QuickTime: QuickTime File Format.

'tref' Track reference atom.

This is a QT container atom; it is not declared in the header files. You can create it with QTNewAtomContainer and insert it with QTInsertChild, using the following parameters:

Fields
atomType
Discussion

Constant TrackHeaderAID, designating atom type 'tref'.

data
Discussion

One track reference atom of a type listed below.

Parent Atom
'trak'
Parent atom can contain only one atom of this type.
Required Child Atoms (one from this list)
'tmcd'
Time code track reference type atom. Only one allowed.
'chap'
Chapter or scene list track reference type atom. Only one allowed.
'sync'
Synchronization track reference type atom. Only one allowed.
'scpt'
Transcript track reference type atom. Only one allowed.
'ssrc'
Nonprimary source track reference type atom. Only one allowed.
'hint'
Hint track reference type atom. Only one allowed.
See Also

For general information about atoms, see Inside QuickTime: QuickTime File Format.

'trpy' Total number of bytes that will be sent, including 12-byte RTP headers, but not including network headers.

This is a QT leaf atom; it is not declared in the header files. You can create it with QTInsertChild using the following parameters:

Fields
atomType
Discussion

Value is 'trpy'.

data
Discussion

8 bytes.

Parent Atom
'hinf'
Parent atom can contain only one atom of this type.
See Also

For general information about atoms, see Inside QuickTime: QuickTime File Format.

'twdt' Tween data type atom.

This is a QT leaf atom; it is not declared in the header files. You can create it with QTInsertChild using the following parameters:

Fields
atomType
Discussion

Value is 'twdt'.

data
Discussion

Tween data.

Parent Atom
'twen'
Parent atom can contain only one atom of this type.
See Also

For general information about atoms, see Inside QuickTime: QuickTime File Format.

'twdu' Tween duration atom.

This is a QT leaf atom; it is not declared in the header files. You can create it with QTInsertChild using the following parameters:

Fields
atomType
Discussion

Constant kTweenDuration, designating atom type 'twdu'.

data
Discussion

Tween duration data.

Parent Atom
'twen'
Parent atom can contain only one atom of this type.
See Also

For general information about atoms, see Inside QuickTime: QuickTime File Format.

'twen' Tween entry atom.

This is a QT container atom; it is not declared in the header files. You can create it with QTNewAtomContainer and insert it with QTInsertChild, using the following parameter:

Fields
atomType
Discussion

Constant kTweenEntry, designating atom type 'twen'.

Required Child Atoms
'twst'
Tween start atom. Only one allowed.
'twdu'
Tween duration atom. Only one allowed.
'twdt'
Tween data type atom. Only one allowed.
'twnt'
Tween type atom. Only one allowed.
See Also

See the TweenSequenceEntryRecord structure. For general information about atoms, see Inside QuickTime: QuickTime File Format.

'twnt' Tween type atom.

This is a QT leaf atom; it is not declared in the header files. You can create it with QTInsertChild using the following parameters:

Fields
atomType
Discussion

Constant kTweenType, designating atom type 'twnt'.

data
Discussion

A tween type; see Tween Types.

Parent Atom
'twen'
Parent atom can contain only one atom of this type.
See Also

For general information about atoms, see Inside QuickTime: QuickTime File Format.

'twst' Tween start offset atom.

This is a QT leaf atom; it is not declared in the header files. You can create it with QTInsertChild using the following parameters:

Fields
atomType
Discussion

Constant kTweenStartOffset, designating atom type 'twst'.

data
Discussion

Tween start offset.

Parent Atom
'twen'
Parent atom can contain only one atom of this type.
See Also

For general information about atoms, see Inside QuickTime: QuickTime File Format.

' ty' Input atom type.

This is a QT leaf atom; it is not declared in the header files. You can create it with QTInsertChild using the following parameters:

Fields
atomType
Discussion

Value is ' ty'; first and second characters are spaces.

data
Discussion

Track input atom type code.

Parent Atom
' in'
Parent atom can contain only one atom of this type.
See Also

For general information about atoms, see Inside QuickTime: QuickTime File Format.

'udta' Holds one or more structures of movie user data.

struct UserDataAtom {
long size;
long atomType;
MoviesUserData userData[1];
};

Fields
size
Discussion

The size in bytes of this atom structure.

atomType
Discussion

Constant UserDataAID, designating atom type 'udta'.

userData
Discussion

An array of MoviesUserData data structures, which contain the actual data for this atom. The currently defined types are listed below.

Parent atom (one or the other)
'moov'
Parent atom can contain any number of atoms of this type.
'trak'
Parent atom can contain any number of atoms of this type.
Optional child atom
' ccpy'
Copyright statement.
' cday'
Date the movie content was created.
' cdir'
Name of movie's director.
' ced1'
First edit date and description. Similar for ' ced2' through ' ced9'.
' cfmt'
Indication of movie format (computer-generated, digitized, and so on).
' cinf'
Information about the movie.
' cprd'
Name of movie's producer.
' cprf'
Names of performers.
' creq'
Special hardware and software requirements.
' csrc'
Credits for those who provided movie source content.
' cwrt'
Name of movie's writer.
'WLOC'
Default window location for movie. Two 16-bit values, {x,y}.
'name'[userdata]
Name of object.
'LOOP'
Looping. Long integer indicating looping style. 0 for none, 1 for looping, 2 for palindromic looping.
'SelO'
Play selection only. Byte indicating that only the selected area of the movie should be played.
'AllF'
Play all frames. Byte indicating that all frames of video should be played, regardless of timing.
Discussion

Inside the user data atom is a list of atoms describing each piece of user data. Each data element contains size and type information along with the data. Furthermore, for historical reasons, the list of atoms is optionally terminated by a 32-bit integer set to 0. If you are writing a program to read user data atoms, you should allow for the terminating 0. However, if you are writing a program to create user data atoms, you can safely leave out the trailing 0.

Programming Info
C interface file: MoviesFormat.h
See Also

See the MoviesUserData structure. For general information about atoms, see Inside QuickTime: QuickTime File Format.

'url ' Contains a URL for a sprite.

This is a QT container atom; it is not declared in the header files. You can create it with QTNewAtomContainer and insert it with QTInsertChild, using the following parameter:

Fields
atomType
Discussion

Value is 'url '.

See Also

For general information about atoms, see Inside QuickTime: QuickTime File Format.

'uses' Lets a sprite specify the subset of images that its image index property can refer to.

This is a QT container atom; it is not declared in the header files. You can create it with QTNewAtomContainer and insert it with QTInsertChild, using the following parameter:

Fields
atomType
Discussion

Value is 'uses'.

Parent Atom
'sprt'
A key frame sprite definition.
See Also

For general information about atoms, see Inside QuickTime: QuickTime File Format.

'vars' Contains variables for a sprite.

This is a QT container atom; it is not declared in the header files. You can create it with QTNewAtomContainer and insert it with QTInsertChild, using the following parameter:

Fields
atomType
Discussion

Value is 'vars'.

Optional Child Atoms
'flov'
Contains a floating-point variable for a sprite. Multiple atoms allowed.
'strv'
Contains a string variable for a sprite. Multiple atoms allowed.
See Also

For general information about atoms, see Inside QuickTime: QuickTime File Format.

'vide' Contains compression information for the Base Image Exporter.

This is a QT atom; it is not declared in the header files. You can create it with QTInsertChild using the following parameter:

Fields
atomType
Discussion

Constant VideoMediaType, designating atom type 'vide'; see Component Identifiers.

Optional Child Atoms
'dasz'
Only one allowed. If present, it specifies a desired data size. The base exporter repeats compression attempts, decreasing the quality parameter until it reaches this size or lower, or it runs out of patience.
'reso'
Only one allowed. If present, it specifies the resolution for the pixmap passed to the compressor.
See Also

For general information about atoms, see Inside QuickTime: QuickTime File Format.

'vmhd'[media] Stores handler-specific information for video media in a track.

struct VideoMediaInfo {
long size;
long atomType;
VideoMediaInfoHeaderAtom header;
HandlerAtom dataHandler;
DataInfoAtom dataInfo;
SampleTableAtom sampleTable;
};

Fields
size
Discussion

The size in bytes of this atom structure.

atomType
Discussion

Constant VideoMediaInfoAID, designating atom type 'vmhd'.

header
Discussion

A 'vmhd'[transfer] atom, which defines the graphics transfer mode for this video media.

dataHandler
Discussion

A 'hdlr' atom that specifies the component that is to handle this media.

dataInfo
Discussion

A 'dinf' atom, which specifies where the video media data is stored.

sampleTable
Discussion

A 'stbl' atom, which tells the media handler how to locate and interpret data samples.

Discussion

This atom stores handler-specific information for the media that constitutes a video track. A video media handler uses this information to map from media time to media data. Another type of media handler would not know how to interpret this information.

Programming Info
C interface file: MoviesFormat.h
See Also

See the 'minf'[sound] atom for sound media and the 'minf'[generic] atom for media other than video or sound. Also see the VideoMediaInfoHeader structure. For general information about atoms, see Inside QuickTime: QuickTime File Format.

'vmhd'[transfer] Defines the graphics transfer characteristics for a video media.

struct VideoMediaInfoHeaderAtom {
long size;
long atomType;
VideoMediaInfoHeader vmiHeader;
};

Fields
size
Discussion

The size in bytes of this atom structure.

atomType
Discussion

Constant VideoMediaInfoHeaderAID, designating atom type 'vmhd'.

vmiHeader
Discussion

A VideoMediaInfoHeader data structure, which contains the actual data for this atom.

Programming Info
C interface file: MoviesFormat.h
See Also

For the structure that contains this atom, see 'minf'[video]. Also see the VideoMediaInfoHeader structure. For general information about atoms, see Inside QuickTime: QuickTime File Format.

'vrcp' Custom cursor atom parent.

This is a QT container atom; it is not declared in the header files. You can create it with QTNewAtomContainer and insert it with QTInsertChild, using the following parameter:

Fields
atomType
Discussion

Constant kQTVRCursorParentAtomType, designating atom type 'vrcp'.

Required Child Atoms
'CURS'
Custom cursor child atom. Multiple atoms of this type allowed.
'crsr'
Color custom cursor child atom. Multiple atoms of this type allowed.
See Also

For general information about atoms, see Inside QuickTime: QuickTime File Format.

'vrni' QTVR node ID atom.

This is a QT container atom; it is not declared in the header files. You can create it with QTNewAtomContainer and insert it with QTInsertChild, using the following parameter:

Fields
atomType
Discussion

Constant kQTVRNodeIDAtomType, designating atom type 'vrni'.

Parent Atom
'vrnp'
Parent atom can contain any number of atoms of this type.
Required Child Atoms
'nloc'
QTVR node location atom. Only one allowed.
See Also

For general information about atoms, see Inside QuickTime: QuickTime File Format.

'vrnp' QTVR node parent atom.

This is a QT container atom; it is not declared in the header files. You can create it with QTNewAtomContainer and insert it with QTInsertChild, using the following parameter:

Fields
atomType
Discussion

Constant kQTVRNodeParentAtomType, designating atom type 'vrnp'.

Required Child Atoms
'vrni'
QTVR node ID atom. Any number allowed.
See Also

For general information about atoms, see Inside QuickTime: QuickTime File Format.

'vrsc' VR world header atom.

This is a QT leaf atom; it is not declared in the header files. You can create it with QTInsertChild using the following parameters:

Fields
atomType
Discussion

Constant kQTVRWorldHeaderAtomType, designating atom type 'vrsc'.

data
Discussion

Contains the name of the scene and the default node ID.

See Also

For general information about atoms, see Inside QuickTime: QuickTime File Format.

'vrsg' Contains the name of a VR scene.

This is a QT leaf atom that contains a struct in its data field. Using the constant kQTVRStringAtomType and a pointer to the atom, you can access its data with QTGetAtomDataPtr and change it with QTSetAtomData. The struct is declared as follows:

struct QTVRStringAtom {
UInt16 stringUsage;
UInt16 stringLength;
unsigned char theString[4];
};

Fields
stringUsage
Discussion

Unused field.

stringLength
Discussion

The length of the name string in bytes.

theString
Discussion

The name as a C string.

Discussion

One leaf atom of this type is contained in a VR world container. You can get a pointer to this container by calling QTVRGetVRWorld. One of this atom's siblings in the VR world is a 'vrsc' atom, which contains the atom ID of this atom in its nameAtomID field. The following code illustrates a function that returns the name of a VR node as a Pascal string, given the node's ID:

OSErr MyGetNodeName (QTVRInstance theInstance, UInt32 theNodeID,
                     StringPtr theStringPtr)
{
    OSErr                        theErr =noErr;
    QTAtomContainer              theNodeInfo;
    QTVRNodeHeaderAtomPtr        theNodeHeader;
    QTAtom                       theNodeHeaderAtom =0;
 
    // Get the node information atom container
    theErr =QTVRGetNodeInfo(theInstance, theNodeID, &theNodeInfo);
 
    // Get the node header atom.
    if (!theErr)
        theNodeHeaderAtom =QTFindChildByID(theNodeInfo,
                                           kParentAtomIsContainer,
                                            kQTVRNodeHeaderAtomType, 1, nil);
    if (theNodeHeaderAtom !=0) {
        QTLockContainer(theNodeInfo);
 
        // Get a pointer to the node header atom data.
        theErr =QTGetAtomDataPtr(theNodeInfo, theNodeHeaderAtom, nil,
                                  (Ptr *)&theNodeHeader);
        // See if there is a name atom.
        if (!theErr && theNodeHeader->
nameAtomID !=0) {
            QTAtom theNameAtom;
            theNameAtom =QTFindChildByID(theNodeInfo,
                          kParentAtomIsContainer, kQTVRStringAtomType,
                          theNodeHeader->
nameAtomID, nil);
            if (theNameAtom !=0) {
                VRStringAtomPtr theStringAtomPtr;
 
                // Get a pointer to the name atom data; copy it into string
                theErr =QTGetAtomDataPtr(theNodeInfo, theNameAtom, nil,
                                          (Ptr *)&theStringAtomPtr);
                if (!theErr) {
                    short theLen =theStringAtomPtr->
stringLength;
                    if (theLen >
255)
                        theLen =255;
                    BlockMove(theStringAtomPtr->
theString,
                              &theStringPtr[1], theLen);
                    theStringPtr[0] =theLen;
                }
            }
        }
        QTUnlockContainer(theNodeInfo);
    }
    QTDisposeAtomContainer(theNodeInfo);
    return(theErr);
}
Programming Info
C interface file: QuickTimeVRFormat.h
See Also

For general information about atoms, see Inside QuickTime: QuickTime File Format.

'wide' Wide atom name placeholder atom.

This is a QT leaf atom; it is not declared in the header files. You can create it with QTInsertChild using the following parameters:

Fields
atomType
Discussion

Constant WideAtomPlaceholderType, designating atom type 'wide'.

data
Discussion

8 bytes of placeholder space to allow an atom to be converted from a 32-bit to a 64-bit atom.

See Also

For general information about atoms, see Inside QuickTime: QuickTime File Format.

'WLOC' User data list entry atom: default window location for movie.

struct MoviesUserData {
long size;
long udType;
char data[1];
};

Fields
size
Discussion

The size in bytes of this atom structure.

udType
Discussion

Value is 'WLOC'.

data
Discussion

2 16-bit values, {x,y}.

Parent Atom
'udta'
Parent atom can contain only one atom of this type.
Programming Info
C interface file: MoviesFormat.h
See Also

For general information about atoms, see Inside QuickTime: QuickTime File Format.

'wtxt' Parent atom for hypertext items.

This is a QT container atom; it is not declared in the header files. You can create it with QTNewAtomContainer and insert it with QTInsertChild, using the following parameter:

Fields
atomType
Discussion

Value is 'wtxt'.

Required Child Atoms
'strt'
Defines the starting offset of hypertext in a text stream. Only one allowed.
'end '
Defines the ending offset of hypertext in a text stream. Only one allowed.
Optional Child Atoms
'htxt'
Multiple atoms allowed.
See Also

For general information about atoms, see Inside QuickTime: QuickTime File Format.



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Last updated: 2006-05-23

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