A LIST chunk defines a list of sub-chunks and has the following format.
|Byte sequence description||Length in bytes||Starts with byte in the chunk||Value|
|chunk ID||4||0x00||The ASCII character string "LIST"|
|size||4||0x04||The size of the sub-chunk less 8 (less the "chunk ID" and the "size")|
|list type ID||4||0x08||Various ASCII character strings. Two common types are "adtl" (associated data list) and "INFO" (text information about copyright, authorship, etc.)|
|data||various||0x0C||Depends 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 description||Length in bytes||Starts with byte in the sub-chunk||Value|
|sub-chunk ID||4||0x00||The ASCII character string "labl" or "note"|
|size||4||0x04||The size of the chunk less 8 (less the "sub-chunk ID" and the "size")|
|cue point ID||4||0x08||The ID of the relevant cue point (see Cue chunk (of a Wave file))|
|data||various||0x0C||Some 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 description||Length in bytes||Starts at byte in the sub-chunk||Value|
|sub-chunk ID||4||0x00||The ASCII character string "ltxt"|
|size||4||0x04||The size of the sub-chunk less 8 (less the "sub-chunk ID" and the "size")|
|cue point ID||4||0x08||The ID of the relevant cue point|
|sample length||4||0x0C||The number of samples in the segment of audio data described by this chunk|
|purpose ID||4||0x10||The purpose of the text. Common IDs are "scrp" for script and "capt" for closed captioning|
|country||2||0x14||The country of the text|
|language||2||0x16||The language of the text|
|dialect||2||0x18||The dialect of the text|
|code page||2||0x1A||The code page for the text|
|data||various||0x1C||Some 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
Info ID (4 byte ASCII text) for information 2
Size of text 2
Common info IDs in Wave files are as follows.
|Info ID||The corresponding text describes|
|IARL||The location where the subject of the file is archived|
|IART||The artist of the original subject of the file|
|ICMS||The name of the person or organization that commissioned the original subject of the file|
|ICMT||General comments about the file or its subject|
|ICOP||Copyright information about the file (e.g., "Copyright Some Company 2011")|
|ICRD||The date the subject of the file was created (creation date)|
|ICRP||Whether and how an image was cropped|
|IDIM||The dimensions of the original subject of the file|
|IDPI||Dots per inch settings used to digitize the file|
|IENG||The name of the engineer who worked on the file|
|IGNR||The genre of the subject|
|IKEY||A list of keywords for the file or its subject|
|ILGT||Lightness settings used to digitize the file|
|IMED||Medium for the original subject of the file|
|INAM||Title of the subject of the file (name)|
|IPLT||The number of colors in the color palette used to digitize the file|
|IPRD||Name of the title the subject was originally intended for|
|ISBJ||Description of the contents of the file (subject)|
|ISFT||Name of the software package used to create the file|
|ISRC||The name of the person or organization that supplied the original subject of the file|
|ISRF||The original form of the material that was digitized (source form)|
|ITCH||The name of the technician who digitized the subject file|
All text must be word aligned.
Wave file format