List chunk (of a Wave file)

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A LIST chunk defines a list of sub-chunks and has the following format.


Byte sequence descriptionLength in bytesStarts with byte in the chunkValue
chunk ID40x00The ASCII character string "LIST"
size40x04The size of the sub-chunk less 8 (less the "chunk ID" and the "size")
list type ID40x08Various ASCII character strings. Two common types are "adtl" (associated data list) and "INFO" (text information about copyright, authorship, etc.)
datavarious0x0CDepends on the list type ID

LIST chunks in the RIFF context

The LIST chunk is defined in the Resource Interchange File Format (RIFF). The LIST chunk can therefore be a part of any file with a format that extends RIFF, such as WAVE, JPEG, or Downloadable Sound (DLS).

The list type INFO is also a part of the RIFF specifications. LIST chunks with the type INFO can exist not only in wave files, but also in other files with a format that extend RIFF. Thus, the LIST chunk with the type INFO is designed to contain information that may or may not have a meaning for wave files (the information that such a LIST chunk may contain is described below).

Formats that extend RIFF may specify list types that are specific to the format and will not exist in other formats that extend RIFF. The list type adtl is specific to the wave file format. Similarly, other formats that extend RIFF may contain LIST chunks that are not a part of the wave file format. For example, the DLS file format allows for LIST chunks with the type wvpl ("wave pool") or ins ("instruments").

List type adtl

An associated data list defines text labels and names for cue points. An associated data list typically uses label sub-chunks, note sub-chunks, and labeled text sub-chunks.

A label sub-chunk and a note sub-chunk have the same structure.


Byte sequence descriptionLength in bytesStarts with byte in the sub-chunkValue
sub-chunk ID40x00The ASCII character string "labl" or "note"
size40x04The size of the chunk less 8 (less the "sub-chunk ID" and the "size")
cue point ID40x08The ID of the relevant cue point (see Cue chunk (of a Wave file))
datavarious0x0CSome ASCII text

The ASCII text is null terminated and must be padded, if not word aligned.

The labeled text sub-chunk associates some portion of the audio data with text and serves as a marker. This sub-chunk has the following format.


Byte sequence descriptionLength in bytesStarts at byte in the sub-chunkValue
sub-chunk ID40x00The ASCII character string "ltxt"
size40x04The size of the sub-chunk less 8 (less the "sub-chunk ID" and the "size")
cue point ID40x08The ID of the relevant cue point
sample length40x0CThe number of samples in the segment of audio data described by this chunk
purpose ID40x10The purpose of the text. Common IDs are "scrp" for script and "capt" for closed captioning
country20x14The country of the text
language20x16The language of the text
dialect20x18The dialect of the text
code page20x1AThe code page for the text
datavarious0x1CSome ASCII text

The labeled text sub-chunk is always a part of an associated data list chunk.

List type INFO

When a LIST chunk carries the list type ID "INFO", the list contains information about the copyright, author, engineer of the file, and other similar text. The data of the LIST chunk is organized as follows.

Info ID (4 byte ASCII text) for information 1
Size of text 1
Text 1
Info ID (4 byte ASCII text) for information 2
Size of text 2
Text 2

Common info IDs in Wave files are as follows.


Info IDThe corresponding text describes
IARLThe location where the subject of the file is archived
IARTThe artist of the original subject of the file
ICMSThe name of the person or organization that commissioned the original subject of the file
ICMTGeneral comments about the file or its subject
ICOPCopyright information about the file (e.g., "Copyright Some Company 2011")
ICRDThe date the subject of the file was created (creation date)
ICRPWhether and how an image was cropped
IDIMThe dimensions of the original subject of the file
IDPIDots per inch settings used to digitize the file
IENGThe name of the engineer who worked on the file
IGNRThe genre of the subject
IKEYA list of keywords for the file or its subject
ILGTLightness settings used to digitize the file
IMEDMedium for the original subject of the file
INAMTitle of the subject of the file (name)
IPLTThe number of colors in the color palette used to digitize the file
IPRDName of the title the subject was originally intended for
ISBJDescription of the contents of the file (subject)
ISFTName of the software package used to create the file
ISRCThe name of the person or organization that supplied the original subject of the file
ISRFThe original form of the material that was digitized (source form)
ITCHThe name of the technician who digitized the subject file

All text must be word aligned.

See also:
Wave file format



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mic
This is correct. It should be "ltxt". It is now fixed.
Posted At 11-08-2016 10:11:32

Richard Lee
As per the above comment - the second listl/note table is incorrect - the ChunkId should read "ltxt” (labelled text) not "note"/"labl".
Posted At 10-05-2015 01:34:44

The "labl" or "note" tables (above) seem to replicate but the first row "Byte sequence description" is sub-chunk ID vs chunk-ID... My assumption is that the tables are documenting the same sub-chunk - and as a result the use of "chunk-ID" in the second table is incorrect --- If my assumption is correct I would remove the redundant table because it suggests that there are two chunk/sub-chunks that have the same "Byte sequence description"
Posted At 08-02-2015 18:03:46



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