Class: Mpeg4File

November 25, 2024 · View on GitHub

node-taglib-sharp / Exports / Mpeg4File

Class: Mpeg4File

Provides tagging and properties support for Mpeg4 files.

Name	Type
`file`	`string` \| `IFileAbstraction`
`readStyle`	`ReadStyle`

Accessors

corruptionReasons

• get corruptionReasons(): string[]

Reasons for which this file is marked as corrupt.

fileAbstraction

• get fileAbstraction(): IFileAbstraction

Gets the IFileAbstraction representing the file.

hasTags

• get hasTags(): boolean

Shortcut property to determine if a file has tags in memory. NOTE: Just because tag !== undefined does not mean there are tags in memory.

isPossiblyCorrupt

• get isPossiblyCorrupt(): boolean

Indicates whether this file may be corrupt. Files with unknown corruptions should not be written.

isWritable

• get isWritable(): boolean

Indicates whether tags can be written back to the current file.

length

• get length(): number

Gets the length of the file represented by the current instance. Value will be 0 if the file is not open for reading;

mimeType

• get mimeType(): string

Gets the MimeType of the file as determined during creation of the instance.

Name	Type	Description
`val`	`FileAccessMode`	File access mode to change to

name

• get name(): string

Gets the name of the file as stored in its file abstraction.

position

• get position(): number

Gets the seek position in the internal stream used by the current instance. Value will be 0 if the file is not open for reading

properties

• get properties(): Properties

Gets the media properties of the file represented by the current instance.

tagTypes

• get tagTypes(): TagTypes

Gets the tag types contained in the current instance.

Name	Type
`value`	`TagTypes`

bufferSize

• Static get bufferSize(): number

Gets the buffer size to use when reading large blocks of data

Methods

dispose

▸ dispose(): void

Dispose the current instance. Equivalent to setting the mode to closed.

find

▸ find(pattern, startPosition?, before?): number

Searches forward through a file for a specified pattern, starting at a specified offset.

Throws

Error Thrown if pattern is not provided or startPosition is not a positive, safe integer.

Parameters

Name	Type	Default value	Description
`pattern`	`ByteVector`	`undefined`	Pattern to search for in the current instance. Must be smaller than the
`startPosition`	`number`	`0`	Seek position to start searching. Must be positive, safe integer.
`before?`	`ByteVector`	`undefined`	Optional pattern that the searched for pattern must appear before. If this pattern is found first, `-1` is returned.

Returns

number

Index at which the value was found. If not found, -1 is returned.

Name	Type	Description
`types`	`TagTypes`	Type of tag to read.
`create`	`boolean`	Whether or not to try and create the tag if one is not found. `true` does not guarantee the tag will be created. For example, trying to create an ID3v2 tag on an OGG Vorbis file will always fail.

Name	Type	Default value	Description
`data`	`ByteVector`	`undefined`	Data to insert into the file.
`start`	`number`	`undefined`	Index into the file at which to insert the data. Must be safe positive integer.
`replace`	`number`	`0`	Number of bytes to replace. Typically, this is the original size of the data block so that a new block will replace the old one.

Name	Type	Description
`reason`	`string`	Reason why this file is considered to be corrupt

preSave

▸ Protected preSave(): void

Prepares to save the file. This must be called at the beginning of every File.save() method.

rFind

▸ rFind(pattern, startPosition?): number

Searches backwards through a file for a specified pattern, starting at a specified offset.

Throws

Error Thrown if pattern was not provided or if startPosition is not a safe, positive integer.

Parameters

Name	Type	Default value	Description
`pattern`	`ByteVector`	`undefined`	Pattern to search for in the current instance. Must be shorter than the bufferSize
`startPosition`	`number`	`0`	Number of bytes from end of the file to begin searching.

Returns

number

Index at which the value wa found. If not found, -1 is returned.

readBlock

▸ readBlock(length): ByteVector

Reads a specified number of bytes at the current seek position from the current position. This method reads the block of data at the current seek position. To change the seek position, use seek.

Throws

Error Thrown when length is not a positive, safe integer.

Parameters

Name	Type	Description
`length`	`number`	Number of bytes to read.

Returns

ByteVector

Object containing the data read from the current instance.

Name	Type	Description
`start`	`number`	Index into the file at which to remove data. Must be safe, positive integer.
`length`	`number`	Number of bytes to remove. Must be a safe integer.

Name	Type	Description
`types`	`TagTypes`	Bitwise combined TagTypes value containing the tag types to be removed from the file

save

▸ save(): void

Saves the changes made in the current instance to the file it represents.

Name	Type	Default value	Description
`offset`	`number`	`undefined`	Byte offset to seek to. Must be a safe, positive integer.
`origin`	`SeekOrigin`	`SeekOrigin.Begin`	Origin from which to seek

Name	Type	Description
`length`	`number`	Number of bytes to resize the file to, must be a safe, positive integer.

Writes a block of data to the file represented by the current instance at the current seek position. This will overwrite any existing data at the seek position and append new data to the file if writing past the current end.

Throws

Error Thrown when data is not provided.

Parameters

Name	Type	Description
`data`	`ByteVector`	ByteVector containing data to the current instance.

Returns

void

Inherited from

File.writeBlock

addFileType

▸ Static addFileType(mimeType, constructor, override?): void

Registers the constructor for a subclass of File with the MimeType it is associated with. Optionally, the MimeType can be forcefully overridden if it was already registered.

Parameters

Name	Type	Default value	Description
`mimeType`	`string`	`undefined`	MimeType to register this subclass constructor to.
`constructor`	`FileTypeConstructor`	`undefined`	Constructor for a subclass of File that will be called if a file with a MimeType of `mimeType` is created.
`override`	`boolean`	`false`	If `true` and a subclass of File was already registered to `mimeType`, it will be forcefully overridden. If `false`, an `Error` will be thrown if a subclass already registered to the MimeType.

Returns

void

Inherited from

File.addFileType

addFileTypeResolver

▸ Static addFileTypeResolver(resolver): void

Registers a FileTypeResolver to the front of the list of file type resolvers.

Parameters

Name	Type	Description
`resolver`	`FileTypeResolver`	Function to handle resolving a subclass of File from an IFileAbstraction

Name	Type	Default value	Description
`abstraction`	`IFileAbstraction`	`undefined`	Object to use when reading/writing from the current instance.
`mimeType?`	`string`	`undefined`	Optional, MimeType to use for determining the subclass of File to return. If omitted, the MimeType will be guessed based on the file's extension.
`propertiesStyle`	`ReadStyle`	`ReadStyle.Average`	Optional, level of detail to use when reading the media information from the new instance. If omitted, Average is used.

Name	Type	Default value	Description
`filePath`	`string`	`undefined`	Path to the file to read/write.
`mimeType?`	`string`	`undefined`	Optional, MimeType to use for determining the subclass of File to return. If omitted, the MimeType will be guessed based on the file's extension.
`propertiesStyle`	`ReadStyle`	`ReadStyle.Average`	Optional, level of detail to use when reading the media information from the new instance. If omitted Average is used.

Name	Type
`mimeType`	`string`

Name	Type
`resolver`	`FileTypeResolver`

Returns

void

Inherited from

File.removeFileTypeResolver