This page hosts a formal specification of ID3v2.3 tag for .mp3 files using Kaitai Struct. This specification can be automatically translated into a variety of programming languages to get a parsing library.
All parsing code for Python generated by Kaitai Struct depends on the Python runtime library. You have to install it before you can parse data.
The Python runtime library can be installed from PyPI:
python3 -m pip install kaitaistructParse a local file and get structure in memory:
data = Id3v23.from_file("path/to/local/file.mp3")
Or parse structure from a bytes:
from kaitaistruct import KaitaiStream, BytesIO
raw = b"\x00\x01\x02..."
data = Id3v23(KaitaiStream(BytesIO(raw)))
After that, one can get various attributes from the structure by invoking getter methods like:
data.tag # => get tag
# This is a generated file! Please edit source .ksy file and use kaitai-struct-compiler to rebuild
import kaitaistruct
from kaitaistruct import KaitaiStruct, KaitaiStream, BytesIO
if getattr(kaitaistruct, 'API_VERSION', (0, 9)) < (0, 9):
raise Exception("Incompatible Kaitai Struct Python API: 0.9 or later is required, but you have %s" % (kaitaistruct.__version__))
class Id3v23(KaitaiStruct):
"""
.. seealso::
Source - https://id3.org/id3v2.3.0
"""
def __init__(self, _io, _parent=None, _root=None):
self._io = _io
self._parent = _parent
self._root = _root if _root else self
self._read()
def _read(self):
self.tag = Id3v23.Tag(self._io, self, self._root)
class U1beSynchsafe(KaitaiStruct):
def __init__(self, _io, _parent=None, _root=None):
self._io = _io
self._parent = _parent
self._root = _root if _root else self
self._read()
def _read(self):
self.padding = self._io.read_bits_int_be(1) != 0
self.value = self._io.read_bits_int_be(7)
class U2beSynchsafe(KaitaiStruct):
def __init__(self, _io, _parent=None, _root=None):
self._io = _io
self._parent = _parent
self._root = _root if _root else self
self._read()
def _read(self):
self.byte0 = Id3v23.U1beSynchsafe(self._io, self, self._root)
self.byte1 = Id3v23.U1beSynchsafe(self._io, self, self._root)
@property
def value(self):
if hasattr(self, '_m_value'):
return self._m_value
self._m_value = ((self.byte0.value << 7) | self.byte1.value)
return getattr(self, '_m_value', None)
class Tag(KaitaiStruct):
"""
.. seealso::
Section 3. ID3v2 overview
"""
def __init__(self, _io, _parent=None, _root=None):
self._io = _io
self._parent = _parent
self._root = _root if _root else self
self._read()
def _read(self):
self.header = Id3v23.Header(self._io, self, self._root)
if self.header.flags.flag_headerex:
self.header_ex = Id3v23.HeaderEx(self._io, self, self._root)
self.frames = []
i = 0
while True:
_ = Id3v23.Frame(self._io, self, self._root)
self.frames.append(_)
if (((self._io.pos() + _.size) > self.header.size.value) or (_.is_invalid)) :
break
i += 1
if self.header.flags.flag_headerex:
self.padding = self._io.read_bytes((self.header_ex.padding_size - self._io.pos()))
class U4beSynchsafe(KaitaiStruct):
def __init__(self, _io, _parent=None, _root=None):
self._io = _io
self._parent = _parent
self._root = _root if _root else self
self._read()
def _read(self):
self.short0 = Id3v23.U2beSynchsafe(self._io, self, self._root)
self.short1 = Id3v23.U2beSynchsafe(self._io, self, self._root)
@property
def value(self):
if hasattr(self, '_m_value'):
return self._m_value
self._m_value = ((self.short0.value << 14) | self.short1.value)
return getattr(self, '_m_value', None)
class Frame(KaitaiStruct):
"""
.. seealso::
Section 3.3. ID3v2 frame overview
"""
def __init__(self, _io, _parent=None, _root=None):
self._io = _io
self._parent = _parent
self._root = _root if _root else self
self._read()
def _read(self):
self.id = (self._io.read_bytes(4)).decode(u"ASCII")
self.size = self._io.read_u4be()
self.flags = Id3v23.Frame.Flags(self._io, self, self._root)
self.data = self._io.read_bytes(self.size)
class Flags(KaitaiStruct):
def __init__(self, _io, _parent=None, _root=None):
self._io = _io
self._parent = _parent
self._root = _root if _root else self
self._read()
def _read(self):
self.flag_discard_alter_tag = self._io.read_bits_int_be(1) != 0
self.flag_discard_alter_file = self._io.read_bits_int_be(1) != 0
self.flag_read_only = self._io.read_bits_int_be(1) != 0
self.reserved1 = self._io.read_bits_int_be(5)
self.flag_compressed = self._io.read_bits_int_be(1) != 0
self.flag_encrypted = self._io.read_bits_int_be(1) != 0
self.flag_grouping = self._io.read_bits_int_be(1) != 0
self.reserved2 = self._io.read_bits_int_be(5)
@property
def is_invalid(self):
if hasattr(self, '_m_is_invalid'):
return self._m_is_invalid
self._m_is_invalid = self.id == u"\000\000\000\000"
return getattr(self, '_m_is_invalid', None)
class HeaderEx(KaitaiStruct):
"""ID3v2 extended header.
.. seealso::
Section 3.2. ID3v2 extended header
"""
def __init__(self, _io, _parent=None, _root=None):
self._io = _io
self._parent = _parent
self._root = _root if _root else self
self._read()
def _read(self):
self.size = self._io.read_u4be()
self.flags_ex = Id3v23.HeaderEx.FlagsEx(self._io, self, self._root)
self.padding_size = self._io.read_u4be()
if self.flags_ex.flag_crc:
self.crc = self._io.read_u4be()
class FlagsEx(KaitaiStruct):
def __init__(self, _io, _parent=None, _root=None):
self._io = _io
self._parent = _parent
self._root = _root if _root else self
self._read()
def _read(self):
self.flag_crc = self._io.read_bits_int_be(1) != 0
self.reserved = self._io.read_bits_int_be(15)
class Header(KaitaiStruct):
"""ID3v2 fixed header.
.. seealso::
Section 3.1. ID3v2 header
"""
def __init__(self, _io, _parent=None, _root=None):
self._io = _io
self._parent = _parent
self._root = _root if _root else self
self._read()
def _read(self):
self.magic = self._io.read_bytes(3)
if not self.magic == b"\x49\x44\x33":
raise kaitaistruct.ValidationNotEqualError(b"\x49\x44\x33", self.magic, self._io, u"/types/header/seq/0")
self.version_major = self._io.read_u1()
self.version_revision = self._io.read_u1()
self.flags = Id3v23.Header.Flags(self._io, self, self._root)
self.size = Id3v23.U4beSynchsafe(self._io, self, self._root)
class Flags(KaitaiStruct):
def __init__(self, _io, _parent=None, _root=None):
self._io = _io
self._parent = _parent
self._root = _root if _root else self
self._read()
def _read(self):
self.flag_unsynchronization = self._io.read_bits_int_be(1) != 0
self.flag_headerex = self._io.read_bits_int_be(1) != 0
self.flag_experimental = self._io.read_bits_int_be(1) != 0
self.reserved = self._io.read_bits_int_be(5)