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733 lines
28 KiB
Text
733 lines
28 KiB
Text
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Informal standard M. Nilsson
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Document: id3v2.4.0-structure.txt 16 September 2001
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ID3 tag version 2.4.0 - Main Structure
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Status of this document
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This document is an informal standard and replaces the ID3v2.3.0
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standard [ID3v2]. A formal standard will use another revision number
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even if the content is identical to document. The contents in this
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document may change for clarifications but never for added or altered
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functionallity.
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Distribution of this document is unlimited.
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Abstract
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This document describes the main structure of ID3v2.4.0, which is a
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revised version of the ID3v2 informal standard [ID3v2] version
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2.3.0. The ID3v2 offers a flexible way of storing audio meta
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information within the audio file itself. The information may be
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technical information, such as equalisation curves, as well as
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title, performer, copyright etc.
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ID3v2.4.0 is meant to be as close as possible to ID3v2.3.0 in order
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to allow for implementations to be revised as easily as possible.
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1. Table of contents
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Status of this document
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Abstract
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1. Table of contents
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2. Conventions in this document
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2. Standard overview
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3. ID3v2 overview
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3.1. ID3v2 header
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3.2. ID3v2 extended header
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3.3. Padding
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3.4. ID3v2 footer
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4. ID3v2 frames overview
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4.1. Frame header flags
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4.1.1. Frame status flags
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4.1.2. Frame format flags
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5. Tag location
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6. Unsynchronisation
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6.1. The unsynchronisation scheme
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6.2. Synchsafe integers
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7. Copyright
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8. References
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9. Author's Address
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2. Conventions in this document
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Text within "" is a text string exactly as it appears in a tag.
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Numbers preceded with $ are hexadecimal and numbers preceded with %
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are binary. $xx is used to indicate a byte with unknown content. %x
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is used to indicate a bit with unknown content. The most significant
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bit (MSB) of a byte is called 'bit 7' and the least significant bit
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(LSB) is called 'bit 0'.
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A tag is the whole tag described in this document. A frame is a block
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of information in the tag. The tag consists of a header, frames and
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optional padding. A field is a piece of information; one value, a
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string etc. A numeric string is a string that consists of the
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characters "0123456789" only.
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The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT",
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"SHOULD", "SHOULD NOT", "RECOMMENDED", "MAY", and "OPTIONAL" in this
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document are to be interpreted as described in RFC 2119 [KEYWORDS].
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3. ID3v2 overview
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ID3v2 is a general tagging format for audio, which makes it possible
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to store meta data about the audio inside the audio file itself. The
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ID3 tag described in this document is mainly targeted at files
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encoded with MPEG-1/2 layer I, MPEG-1/2 layer II, MPEG-1/2 layer III
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and MPEG-2.5, but may work with other types of encoded audio or as a
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stand alone format for audio meta data.
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ID3v2 is designed to be as flexible and expandable as possible to
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meet new meta information needs that might arise. To achieve that
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ID3v2 is constructed as a container for several information blocks,
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called frames, whose format need not be known to the software that
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encounters them. At the start of every frame is an unique and
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predefined identifier, a size descriptor that allows software to skip
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unknown frames and a flags field. The flags describes encoding
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details and if the frame should remain in the tag, should it be
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unknown to the software, if the file is altered.
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The bitorder in ID3v2 is most significant bit first (MSB). The
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byteorder in multibyte numbers is most significant byte first (e.g.
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$12345678 would be encoded $12 34 56 78), also known as big endian
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and network byte order.
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Overall tag structure:
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+-----------------------------+
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| Header (10 bytes) |
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+-----------------------------+
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| Extended Header |
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| (variable length, OPTIONAL) |
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+-----------------------------+
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| Frames (variable length) |
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+-----------------------------+
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| Padding |
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| (variable length, OPTIONAL) |
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+-----------------------------+
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| Footer (10 bytes, OPTIONAL) |
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+-----------------------------+
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In general, padding and footer are mutually exclusive. See details in
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sections 3.3, 3.4 and 5.
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3.1. ID3v2 header
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The first part of the ID3v2 tag is the 10 byte tag header, laid out
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as follows:
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ID3v2/file identifier "ID3"
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ID3v2 version $04 00
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ID3v2 flags %abcd0000
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ID3v2 size 4 * %0xxxxxxx
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The first three bytes of the tag are always "ID3", to indicate that
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this is an ID3v2 tag, directly followed by the two version bytes. The
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first byte of ID3v2 version is its major version, while the second
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byte is its revision number. In this case this is ID3v2.4.0. All
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revisions are backwards compatible while major versions are not. If
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software with ID3v2.4.0 and below support should encounter version
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five or higher it should simply ignore the whole tag. Version or
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revision will never be $FF.
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The version is followed by the ID3v2 flags field, of which currently
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four flags are used.
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a - Unsynchronisation
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Bit 7 in the 'ID3v2 flags' indicates whether or not
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unsynchronisation is applied on all frames (see section 6.1 for
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details); a set bit indicates usage.
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b - Extended header
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The second bit (bit 6) indicates whether or not the header is
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followed by an extended header. The extended header is described in
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section 3.2. A set bit indicates the presence of an extended
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header.
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c - Experimental indicator
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The third bit (bit 5) is used as an 'experimental indicator'. This
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flag SHALL always be set when the tag is in an experimental stage.
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d - Footer present
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Bit 4 indicates that a footer (section 3.4) is present at the very
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end of the tag. A set bit indicates the presence of a footer.
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All the other flags MUST be cleared. If one of these undefined flags
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are set, the tag might not be readable for a parser that does not
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know the flags function.
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The ID3v2 tag size is stored as a 32 bit synchsafe integer (section
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6.2), making a total of 28 effective bits (representing up to 256MB).
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The ID3v2 tag size is the sum of the byte length of the extended
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header, the padding and the frames after unsynchronisation. If a
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footer is present this equals to ('total size' - 20) bytes, otherwise
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('total size' - 10) bytes.
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An ID3v2 tag can be detected with the following pattern:
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$49 44 33 yy yy xx zz zz zz zz
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Where yy is less than $FF, xx is the 'flags' byte and zz is less than
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$80.
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3.2. Extended header
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The extended header contains information that can provide further
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insight in the structure of the tag, but is not vital to the correct
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parsing of the tag information; hence the extended header is
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optional.
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Extended header size 4 * %0xxxxxxx
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Number of flag bytes $01
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Extended Flags $xx
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Where the 'Extended header size' is the size of the whole extended
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header, stored as a 32 bit synchsafe integer. An extended header can
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thus never have a size of fewer than six bytes.
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The extended flags field, with its size described by 'number of flag
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bytes', is defined as:
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%0bcd0000
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Each flag that is set in the extended header has data attached, which
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comes in the order in which the flags are encountered (i.e. the data
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for flag 'b' comes before the data for flag 'c'). Unset flags cannot
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have any attached data. All unknown flags MUST be unset and their
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corresponding data removed when a tag is modified.
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Every set flag's data starts with a length byte, which contains a
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value between 0 and 127 ($00 - $7f), followed by data that has the
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field length indicated by the length byte. If a flag has no attached
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data, the value $00 is used as length byte.
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b - Tag is an update
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If this flag is set, the present tag is an update of a tag found
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earlier in the present file or stream. If frames defined as unique
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are found in the present tag, they are to override any
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corresponding ones found in the earlier tag. This flag has no
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corresponding data.
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Flag data length $00
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c - CRC data present
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If this flag is set, a CRC-32 [ISO-3309] data is included in the
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extended header. The CRC is calculated on all the data between the
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header and footer as indicated by the header's tag length field,
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minus the extended header. Note that this includes the padding (if
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there is any), but excludes the footer. The CRC-32 is stored as an
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35 bit synchsafe integer, leaving the upper four bits always
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zeroed.
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Flag data length $05
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Total frame CRC 5 * %0xxxxxxx
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d - Tag restrictions
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For some applications it might be desired to restrict a tag in more
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ways than imposed by the ID3v2 specification. Note that the
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presence of these restrictions does not affect how the tag is
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decoded, merely how it was restricted before encoding. If this flag
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is set the tag is restricted as follows:
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Flag data length $01
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Restrictions %ppqrrstt
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p - Tag size restrictions
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00 No more than 128 frames and 1 MB total tag size.
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01 No more than 64 frames and 128 KB total tag size.
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10 No more than 32 frames and 40 KB total tag size.
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11 No more than 32 frames and 4 KB total tag size.
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q - Text encoding restrictions
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0 No restrictions
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1 Strings are only encoded with ISO-8859-1 [ISO-8859-1] or
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UTF-8 [UTF-8].
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r - Text fields size restrictions
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00 No restrictions
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01 No string is longer than 1024 characters.
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10 No string is longer than 128 characters.
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11 No string is longer than 30 characters.
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Note that nothing is said about how many bytes is used to
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represent those characters, since it is encoding dependent. If a
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text frame consists of more than one string, the sum of the
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strungs is restricted as stated.
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s - Image encoding restrictions
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0 No restrictions
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1 Images are encoded only with PNG [PNG] or JPEG [JFIF].
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t - Image size restrictions
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00 No restrictions
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01 All images are 256x256 pixels or smaller.
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10 All images are 64x64 pixels or smaller.
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11 All images are exactly 64x64 pixels, unless required
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otherwise.
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3.3. Padding
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It is OPTIONAL to include padding after the final frame (at the end
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of the ID3 tag), making the size of all the frames together smaller
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than the size given in the tag header. A possible purpose of this
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padding is to allow for adding a few additional frames or enlarge
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existing frames within the tag without having to rewrite the entire
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file. The value of the padding bytes must be $00. A tag MUST NOT have
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any padding between the frames or between the tag header and the
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frames. Furthermore it MUST NOT have any padding when a tag footer is
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added to the tag.
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3.4. ID3v2 footer
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To speed up the process of locating an ID3v2 tag when searching from
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the end of a file, a footer can be added to the tag. It is REQUIRED
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to add a footer to an appended tag, i.e. a tag located after all
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audio data. The footer is a copy of the header, but with a different
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identifier.
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ID3v2 identifier "3DI"
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ID3v2 version $04 00
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ID3v2 flags %abcd0000
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ID3v2 size 4 * %0xxxxxxx
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4. ID3v2 frame overview
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All ID3v2 frames consists of one frame header followed by one or more
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fields containing the actual information. The header is always 10
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bytes and laid out as follows:
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Frame ID $xx xx xx xx (four characters)
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Size 4 * %0xxxxxxx
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Flags $xx xx
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The frame ID is made out of the characters capital A-Z and 0-9.
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Identifiers beginning with "X", "Y" and "Z" are for experimental
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frames and free for everyone to use, without the need to set the
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experimental bit in the tag header. Bear in mind that someone else
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might have used the same identifier as you. All other identifiers are
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either used or reserved for future use.
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The frame ID is followed by a size descriptor containing the size of
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the data in the final frame, after encryption, compression and
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unsynchronisation. The size is excluding the frame header ('total
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frame size' - 10 bytes) and stored as a 32 bit synchsafe integer.
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In the frame header the size descriptor is followed by two flag
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bytes. These flags are described in section 4.1.
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There is no fixed order of the frames' appearance in the tag,
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although it is desired that the frames are arranged in order of
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significance concerning the recognition of the file. An example of
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such order: UFID, TIT2, MCDI, TRCK ...
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A tag MUST contain at least one frame. A frame must be at least 1
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byte big, excluding the header.
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If nothing else is said, strings, including numeric strings and URLs
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[URL], are represented as ISO-8859-1 [ISO-8859-1] characters in the
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range $20 - $FF. Such strings are represented in frame descriptions
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as <text string>, or <full text string> if newlines are allowed. If
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nothing else is said newline character is forbidden. In ISO-8859-1 a
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newline is represented, when allowed, with $0A only.
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Frames that allow different types of text encoding contains a text
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encoding description byte. Possible encodings:
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$00 ISO-8859-1 [ISO-8859-1]. Terminated with $00.
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$01 UTF-16 [UTF-16] encoded Unicode [UNICODE] with BOM. All
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strings in the same frame SHALL have the same byteorder.
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Terminated with $00 00.
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$02 UTF-16BE [UTF-16] encoded Unicode [UNICODE] without BOM.
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Terminated with $00 00.
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$03 UTF-8 [UTF-8] encoded Unicode [UNICODE]. Terminated with $00.
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Strings dependent on encoding are represented in frame descriptions
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as <text string according to encoding>, or <full text string
|
||
according to encoding> if newlines are allowed. Any empty strings of
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type $01 which are NULL-terminated may have the Unicode BOM followed
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by a Unicode NULL ($FF FE 00 00 or $FE FF 00 00).
|
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The timestamp fields are based on a subset of ISO 8601. When being as
|
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precise as possible the format of a time string is
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yyyy-MM-ddTHH:mm:ss (year, "-", month, "-", day, "T", hour (out of
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24), ":", minutes, ":", seconds), but the precision may be reduced by
|
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removing as many time indicators as wanted. Hence valid timestamps
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are
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yyyy, yyyy-MM, yyyy-MM-dd, yyyy-MM-ddTHH, yyyy-MM-ddTHH:mm and
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yyyy-MM-ddTHH:mm:ss. All time stamps are UTC. For durations, use
|
||
the slash character as described in 8601, and for multiple non-
|
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contiguous dates, use multiple strings, if allowed by the frame
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definition.
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The three byte language field, present in several frames, is used to
|
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describe the language of the frame's content, according to ISO-639-2
|
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[ISO-639-2]. The language should be represented in lower case. If the
|
||
language is not known the string "XXX" should be used.
|
||
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||
All URLs [URL] MAY be relative, e.g. "picture.png", "../doc.txt".
|
||
|
||
If a frame is longer than it should be, e.g. having more fields than
|
||
specified in this document, that indicates that additions to the
|
||
frame have been made in a later version of the ID3v2 standard. This
|
||
is reflected by the revision number in the header of the tag.
|
||
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||
|
||
4.1. Frame header flags
|
||
|
||
In the frame header the size descriptor is followed by two flag
|
||
bytes. All unused flags MUST be cleared. The first byte is for
|
||
'status messages' and the second byte is a format description. If an
|
||
unknown flag is set in the first byte the frame MUST NOT be changed
|
||
without that bit cleared. If an unknown flag is set in the second
|
||
byte the frame is likely to not be readable. Some flags in the second
|
||
byte indicates that extra information is added to the header. These
|
||
fields of extra information is ordered as the flags that indicates
|
||
them. The flags field is defined as follows (l and o left out because
|
||
their resemblence to one and zero):
|
||
|
||
%0abc0000 %0h00kmnp
|
||
|
||
Some frame format flags indicate that additional information fields
|
||
are added to the frame. This information is added after the frame
|
||
header and before the frame data in the same order as the flags that
|
||
indicates them. I.e. the four bytes of decompressed size will precede
|
||
the encryption method byte. These additions affects the 'frame size'
|
||
field, but are not subject to encryption or compression.
|
||
|
||
The default status flags setting for a frame is, unless stated
|
||
otherwise, 'preserved if tag is altered' and 'preserved if file is
|
||
altered', i.e. %00000000.
|
||
|
||
|
||
4.1.1. Frame status flags
|
||
|
||
a - Tag alter preservation
|
||
|
||
This flag tells the tag parser what to do with this frame if it is
|
||
unknown and the tag is altered in any way. This applies to all
|
||
kinds of alterations, including adding more padding and reordering
|
||
the frames.
|
||
|
||
0 Frame should be preserved.
|
||
1 Frame should be discarded.
|
||
|
||
|
||
b - File alter preservation
|
||
|
||
This flag tells the tag parser what to do with this frame if it is
|
||
unknown and the file, excluding the tag, is altered. This does not
|
||
apply when the audio is completely replaced with other audio data.
|
||
|
||
0 Frame should be preserved.
|
||
1 Frame should be discarded.
|
||
|
||
|
||
c - Read only
|
||
|
||
This flag, if set, tells the software that the contents of this
|
||
frame are intended to be read only. Changing the contents might
|
||
break something, e.g. a signature. If the contents are changed,
|
||
without knowledge of why the frame was flagged read only and
|
||
without taking the proper means to compensate, e.g. recalculating
|
||
the signature, the bit MUST be cleared.
|
||
|
||
|
||
4.1.2. Frame format flags
|
||
|
||
h - Grouping identity
|
||
|
||
This flag indicates whether or not this frame belongs in a group
|
||
with other frames. If set, a group identifier byte is added to the
|
||
frame. Every frame with the same group identifier belongs to the
|
||
same group.
|
||
|
||
0 Frame does not contain group information
|
||
1 Frame contains group information
|
||
|
||
|
||
k - Compression
|
||
|
||
This flag indicates whether or not the frame is compressed.
|
||
A 'Data Length Indicator' byte MUST be included in the frame.
|
||
|
||
0 Frame is not compressed.
|
||
1 Frame is compressed using zlib [zlib] deflate method.
|
||
If set, this requires the 'Data Length Indicator' bit
|
||
to be set as well.
|
||
|
||
|
||
m - Encryption
|
||
|
||
This flag indicates whether or not the frame is encrypted. If set,
|
||
one byte indicating with which method it was encrypted will be
|
||
added to the frame. See description of the ENCR frame for more
|
||
information about encryption method registration. Encryption
|
||
should be done after compression. Whether or not setting this flag
|
||
requires the presence of a 'Data Length Indicator' depends on the
|
||
specific algorithm used.
|
||
|
||
0 Frame is not encrypted.
|
||
1 Frame is encrypted.
|
||
|
||
n - Unsynchronisation
|
||
|
||
This flag indicates whether or not unsynchronisation was applied
|
||
to this frame. See section 6 for details on unsynchronisation.
|
||
If this flag is set all data from the end of this header to the
|
||
end of this frame has been unsynchronised. Although desirable, the
|
||
presence of a 'Data Length Indicator' is not made mandatory by
|
||
unsynchronisation.
|
||
|
||
0 Frame has not been unsynchronised.
|
||
1 Frame has been unsyrchronised.
|
||
|
||
p - Data length indicator
|
||
|
||
This flag indicates that a data length indicator has been added to
|
||
the frame. The data length indicator is the value one would write
|
||
as the 'Frame length' if all of the frame format flags were
|
||
zeroed, represented as a 32 bit synchsafe integer.
|
||
|
||
0 There is no Data Length Indicator.
|
||
1 A data length Indicator has been added to the frame.
|
||
|
||
|
||
5. Tag location
|
||
|
||
The default location of an ID3v2 tag is prepended to the audio so
|
||
that players can benefit from the information when the data is
|
||
streamed. It is however possible to append the tag, or make a
|
||
prepend/append combination. When deciding upon where an unembedded
|
||
tag should be located, the following order of preference SHOULD be
|
||
considered.
|
||
|
||
1. Prepend the tag.
|
||
|
||
2. Prepend a tag with all vital information and add a second tag at
|
||
the end of the file, before tags from other tagging systems. The
|
||
first tag is required to have a SEEK frame.
|
||
|
||
3. Add a tag at the end of the file, before tags from other tagging
|
||
systems.
|
||
|
||
In case 2 and 3 the tag can simply be appended if no other known tags
|
||
are present. The suggested method to find ID3v2 tags are:
|
||
|
||
1. Look for a prepended tag using the pattern found in section 3.1.
|
||
|
||
2. If a SEEK frame was found, use its values to guide further
|
||
searching.
|
||
|
||
3. Look for a tag footer, scanning from the back of the file.
|
||
|
||
For every new tag that is found, the old tag should be discarded
|
||
unless the update flag in the extended header (section 3.2) is set.
|
||
|
||
|
||
6. Unsynchronisation
|
||
|
||
The only purpose of unsynchronisation is to make the ID3v2 tag as
|
||
compatible as possible with existing software and hardware. There is
|
||
no use in 'unsynchronising' tags if the file is only to be processed
|
||
only by ID3v2 aware software and hardware. Unsynchronisation is only
|
||
useful with tags in MPEG 1/2 layer I, II and III, MPEG 2.5 and AAC
|
||
files.
|
||
|
||
|
||
6.1. The unsynchronisation scheme
|
||
|
||
Whenever a false synchronisation is found within the tag, one zeroed
|
||
byte is inserted after the first false synchronisation byte. The
|
||
format of synchronisations that should be altered by ID3 encoders is
|
||
as follows:
|
||
|
||
%11111111 111xxxxx
|
||
|
||
and should be replaced with:
|
||
|
||
%11111111 00000000 111xxxxx
|
||
|
||
This has the side effect that all $FF 00 combinations have to be
|
||
altered, so they will not be affected by the decoding process.
|
||
Therefore all the $FF 00 combinations have to be replaced with the
|
||
$FF 00 00 combination during the unsynchronisation.
|
||
|
||
To indicate usage of the unsynchronisation, the unsynchronisation
|
||
flag in the frame header should be set. This bit MUST be set if the
|
||
frame was altered by the unsynchronisation and SHOULD NOT be set if
|
||
unaltered. If all frames in the tag are unsynchronised the
|
||
unsynchronisation flag in the tag header SHOULD be set. It MUST NOT
|
||
be set if the tag has a frame which is not unsynchronised.
|
||
|
||
Assume the first byte of the audio to be $FF. The special case when
|
||
the last byte of the last frame is $FF and no padding nor footer is
|
||
used will then introduce a false synchronisation. This can be solved
|
||
by adding a footer, adding padding or unsynchronising the frame and
|
||
add $00 to the end of the frame data, thus adding more byte to the
|
||
frame size than a normal unsynchronisation would. Although not
|
||
preferred, it is allowed to apply the last method on all frames
|
||
ending with $FF.
|
||
|
||
It is preferred that the tag is either completely unsynchronised or
|
||
not unsynchronised at all. A completely unsynchronised tag has no
|
||
false synchonisations in it, as defined above, and does not end with
|
||
$FF. A completely non-unsynchronised tag contains no unsynchronised
|
||
frames, and thus the unsynchronisation flag in the header is cleared.
|
||
|
||
Do bear in mind, that if compression or encryption is used, the
|
||
unsynchronisation scheme MUST be applied afterwards. When decoding an
|
||
unsynchronised frame, the unsynchronisation scheme MUST be reversed
|
||
first, encryption and decompression afterwards.
|
||
|
||
|
||
6.2. Synchsafe integers
|
||
|
||
In some parts of the tag it is inconvenient to use the
|
||
unsychronisation scheme because the size of unsynchronised data is
|
||
not known in advance, which is particularly problematic with size
|
||
descriptors. The solution in ID3v2 is to use synchsafe integers, in
|
||
which there can never be any false synchs. Synchsafe integers are
|
||
integers that keep its highest bit (bit 7) zeroed, making seven bits
|
||
out of eight available. Thus a 32 bit synchsafe integer can store 28
|
||
bits of information.
|
||
|
||
Example:
|
||
|
||
255 (%11111111) encoded as a 16 bit synchsafe integer is 383
|
||
(%00000001 01111111).
|
||
|
||
|
||
7. Copyright
|
||
|
||
Copyright (C) Martin Nilsson 2000. All Rights Reserved.
|
||
|
||
This document and translations of it may be copied and furnished to
|
||
others, and derivative works that comment on or otherwise explain it
|
||
or assist in its implementation may be prepared, copied, published
|
||
and distributed, in whole or in part, without restriction of any
|
||
kind, provided that a reference to this document is included on all
|
||
such copies and derivative works. However, this document itself may
|
||
not be modified in any way and reissued as the original document.
|
||
|
||
The limited permissions granted above are perpetual and will not be
|
||
revoked.
|
||
|
||
This document and the information contained herein is provided on an
|
||
'AS IS' basis and THE AUTHORS DISCLAIMS ALL WARRANTIES, EXPRESS OR
|
||
IMPLIED, INCLUDING BUT NOT LIMITED TO ANY WARRANTY THAT THE USE OF
|
||
THE INFORMATION HEREIN WILL NOT INFRINGE ANY RIGHTS OR ANY IMPLIED
|
||
WARRANTIES OF MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE.
|
||
|
||
|
||
8. References
|
||
|
||
[ID3v2] Martin Nilsson, 'ID3v2 informal standard'.
|
||
|
||
<url:http://www.id3.org/id3v2.3.0.txt>
|
||
|
||
[ISO-639-2] ISO/FDIS 639-2.
|
||
'Codes for the representation of names of languages, Part 2: Alpha-3
|
||
code.' Technical committee / subcommittee: TC 37 / SC 2
|
||
|
||
[ISO-3309] ISO 3309
|
||
'Information Processing Systems--Data Communication High-Level Data
|
||
Link Control Procedure--Frame Structure', IS 3309, October 1984, 3rd
|
||
Edition.
|
||
|
||
[ISO-8859-1] ISO/IEC DIS 8859-1.
|
||
'8-bit single-byte coded graphic character sets, Part 1: Latin
|
||
alphabet No. 1.' Technical committee / subcommittee: JTC 1 / SC 2
|
||
|
||
[JFIF] 'JPEG File Interchange Format, version 1.02'
|
||
|
||
<url:http://www.w3.org/Graphics/JPEG/jfif.txt>
|
||
|
||
[KEYWORDS] S. Bradner, 'Key words for use in RFCs to Indicate
|
||
Requirement Levels', RFC 2119, March 1997.
|
||
|
||
<url:ftp://ftp.isi.edu/in-notes/rfc2119.txt>
|
||
|
||
[MPEG] ISO/IEC 11172-3:1993.
|
||
'Coding of moving pictures and associated audio for digital storage
|
||
media at up to about 1,5 Mbit/s, Part 3: Audio.'
|
||
Technical committee / subcommittee: JTC 1 / SC 29
|
||
and
|
||
ISO/IEC 13818-3:1995
|
||
'Generic coding of moving pictures and associated audio information,
|
||
Part 3: Audio.'
|
||
Technical committee / subcommittee: JTC 1 / SC 29
|
||
and
|
||
ISO/IEC DIS 13818-3
|
||
'Generic coding of moving pictures and associated audio information,
|
||
Part 3: Audio (Revision of ISO/IEC 13818-3:1995)'
|
||
|
||
[PNG] 'Portable Network Graphics, version 1.0'
|
||
|
||
<url:http://www.w3.org/TR/REC-png-multi.html>
|
||
|
||
[UNICODE] The Unicode Consortium,
|
||
'The Unicode Standard Version 3.0', ISBN 0-201-61633-5.
|
||
|
||
<url:http://www.unicode.org/unicode/standard/versions/Unicode3.0.htm>
|
||
|
||
[URL] T. Berners-Lee, L. Masinter & M. McCahill, 'Uniform Resource
|
||
Locators (URL)', RFC 1738, December 1994.
|
||
|
||
<url:ftp://ftp.isi.edu/in-notes/rfc1738.txt>
|
||
|
||
[UTF-8] F. Yergeau, 'UTF-8, a transformation format of ISO 10646',
|
||
RFC 2279, January 1998.
|
||
|
||
<url:ftp://ftp.isi.edu/in-notes/rfc2279.txt>
|
||
|
||
[UTF-16] F. Yergeau, 'UTF-16, an encoding of ISO 10646', RFC 2781,
|
||
February 2000.
|
||
|
||
<url:ftp://ftp.isi.edu/in-notes/rfc2781.txt>
|
||
|
||
[ZLIB] P. Deutsch, Aladdin Enterprises & J-L. Gailly, 'ZLIB
|
||
Compressed Data Format Specification version 3.3', RFC 1950,
|
||
May 1996.
|
||
|
||
<url:ftp://ftp.isi.edu/in-notes/rfc1950.txt>
|
||
|
||
|
||
9. Author's Address
|
||
|
||
Written by
|
||
|
||
Martin Nilsson
|
||
Rydsv<73>gen 246 C. 30
|
||
SE-584 34 Link<6E>ping
|
||
Sweden
|
||
|
||
Email: nilsson@id3.org
|
||
|