This page hosts a formal specification of ID3v2.4 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 = Id3v24.from_file("path/to/local/file.mp3")
Or parse structure from a bytes:
from kaitaistruct import KaitaiStream, BytesIO
raw = b"\x00\x01\x02..."
data = Id3v24(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
# type: ignore
import kaitaistruct
from kaitaistruct import KaitaiStruct, KaitaiStream, BytesIO
if getattr(kaitaistruct, 'API_VERSION', (0, 9)) < (0, 11):
raise Exception("Incompatible Kaitai Struct Python API: 0.11 or later is required, but you have %s" % (kaitaistruct.__version__))
class Id3v24(KaitaiStruct):
"""
.. seealso::
Source - http://id3.org/id3v2.4.0-structure
.. seealso::
Source - http://id3.org/id3v2.4.0-frames
"""
def __init__(self, _io, _parent=None, _root=None):
super(Id3v24, self).__init__(_io)
self._parent = _parent
self._root = _root or self
self._read()
def _read(self):
self.tag = Id3v24.Tag(self._io, self, self._root)
def _fetch_instances(self):
pass
self.tag._fetch_instances()
class Footer(KaitaiStruct):
def __init__(self, _io, _parent=None, _root=None):
super(Id3v24.Footer, self).__init__(_io)
self._parent = _parent
self._root = _root
self._read()
def _read(self):
self.magic = self._io.read_bytes(3)
if not self.magic == b"\x33\x44\x49":
raise kaitaistruct.ValidationNotEqualError(b"\x33\x44\x49", self.magic, self._io, u"/types/footer/seq/0")
self.version_major = self._io.read_u1()
self.version_revision = self._io.read_u1()
self.flags = Id3v24.Footer.Flags(self._io, self, self._root)
self.size = Id3v24.U4beSynchsafe(self._io, self, self._root)
def _fetch_instances(self):
pass
self.flags._fetch_instances()
self.size._fetch_instances()
class Flags(KaitaiStruct):
def __init__(self, _io, _parent=None, _root=None):
super(Id3v24.Footer.Flags, self).__init__(_io)
self._parent = _parent
self._root = _root
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.flag_footer = self._io.read_bits_int_be(1) != 0
self.reserved = self._io.read_bits_int_be(4)
def _fetch_instances(self):
pass
class Frame(KaitaiStruct):
def __init__(self, _io, _parent=None, _root=None):
super(Id3v24.Frame, self).__init__(_io)
self._parent = _parent
self._root = _root
self._read()
def _read(self):
self.id = (self._io.read_bytes(4)).decode(u"ASCII")
self.size = Id3v24.U4beSynchsafe(self._io, self, self._root)
self.flags_status = Id3v24.Frame.FlagsStatus(self._io, self, self._root)
self.flags_format = Id3v24.Frame.FlagsFormat(self._io, self, self._root)
self.data = self._io.read_bytes(self.size.value)
def _fetch_instances(self):
pass
self.size._fetch_instances()
self.flags_status._fetch_instances()
self.flags_format._fetch_instances()
class FlagsFormat(KaitaiStruct):
def __init__(self, _io, _parent=None, _root=None):
super(Id3v24.Frame.FlagsFormat, self).__init__(_io)
self._parent = _parent
self._root = _root
self._read()
def _read(self):
self.reserved1 = 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(2)
self.flag_compressed = self._io.read_bits_int_be(1) != 0
self.flag_encrypted = self._io.read_bits_int_be(1) != 0
self.flag_unsynchronisated = self._io.read_bits_int_be(1) != 0
self.flag_indicator = self._io.read_bits_int_be(1) != 0
def _fetch_instances(self):
pass
class FlagsStatus(KaitaiStruct):
def __init__(self, _io, _parent=None, _root=None):
super(Id3v24.Frame.FlagsStatus, self).__init__(_io)
self._parent = _parent
self._root = _root
self._read()
def _read(self):
self.reserved1 = self._io.read_bits_int_be(1) != 0
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.reserved2 = self._io.read_bits_int_be(4)
def _fetch_instances(self):
pass
@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 Header(KaitaiStruct):
def __init__(self, _io, _parent=None, _root=None):
super(Id3v24.Header, self).__init__(_io)
self._parent = _parent
self._root = _root
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 = Id3v24.Header.Flags(self._io, self, self._root)
self.size = Id3v24.U4beSynchsafe(self._io, self, self._root)
def _fetch_instances(self):
pass
self.flags._fetch_instances()
self.size._fetch_instances()
class Flags(KaitaiStruct):
def __init__(self, _io, _parent=None, _root=None):
super(Id3v24.Header.Flags, self).__init__(_io)
self._parent = _parent
self._root = _root
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.flag_footer = self._io.read_bits_int_be(1) != 0
self.reserved = self._io.read_bits_int_be(4)
def _fetch_instances(self):
pass
class HeaderEx(KaitaiStruct):
def __init__(self, _io, _parent=None, _root=None):
super(Id3v24.HeaderEx, self).__init__(_io)
self._parent = _parent
self._root = _root
self._read()
def _read(self):
self.size = Id3v24.U4beSynchsafe(self._io, self, self._root)
self.flags_ex = Id3v24.HeaderEx.FlagsEx(self._io, self, self._root)
self.data = self._io.read_bytes(self.size.value - 5)
def _fetch_instances(self):
pass
self.size._fetch_instances()
self.flags_ex._fetch_instances()
class FlagsEx(KaitaiStruct):
def __init__(self, _io, _parent=None, _root=None):
super(Id3v24.HeaderEx.FlagsEx, self).__init__(_io)
self._parent = _parent
self._root = _root
self._read()
def _read(self):
self.reserved1 = self._io.read_bits_int_be(1) != 0
self.flag_update = self._io.read_bits_int_be(1) != 0
self.flag_crc = self._io.read_bits_int_be(1) != 0
self.flag_restrictions = self._io.read_bits_int_be(1) != 0
self.reserved2 = self._io.read_bits_int_be(4)
def _fetch_instances(self):
pass
class Padding(KaitaiStruct):
def __init__(self, _io, _parent=None, _root=None):
super(Id3v24.Padding, self).__init__(_io)
self._parent = _parent
self._root = _root
self._read()
def _read(self):
self.padding = self._io.read_bytes(self._root.tag.header.size.value - self._io.pos())
def _fetch_instances(self):
pass
class Tag(KaitaiStruct):
def __init__(self, _io, _parent=None, _root=None):
super(Id3v24.Tag, self).__init__(_io)
self._parent = _parent
self._root = _root
self._read()
def _read(self):
self.header = Id3v24.Header(self._io, self, self._root)
if self.header.flags.flag_headerex:
pass
self.header_ex = Id3v24.HeaderEx(self._io, self, self._root)
self.frames = []
i = 0
while True:
_ = Id3v24.Frame(self._io, self, self._root)
self.frames.append(_)
if ((self._io.pos() + _.size.value > self.header.size.value) or (_.is_invalid)) :
break
i += 1
if (not (self.header.flags.flag_footer)):
pass
self.padding = Id3v24.Padding(self._io, self, self._root)
if self.header.flags.flag_footer:
pass
self.footer = Id3v24.Footer(self._io, self, self._root)
def _fetch_instances(self):
pass
self.header._fetch_instances()
if self.header.flags.flag_headerex:
pass
self.header_ex._fetch_instances()
for i in range(len(self.frames)):
pass
self.frames[i]._fetch_instances()
if (not (self.header.flags.flag_footer)):
pass
self.padding._fetch_instances()
if self.header.flags.flag_footer:
pass
self.footer._fetch_instances()
class U1beSynchsafe(KaitaiStruct):
def __init__(self, _io, _parent=None, _root=None):
super(Id3v24.U1beSynchsafe, self).__init__(_io)
self._parent = _parent
self._root = _root
self._read()
def _read(self):
self.padding = self._io.read_bits_int_be(1) != 0
self.value = self._io.read_bits_int_be(7)
def _fetch_instances(self):
pass
class U2beSynchsafe(KaitaiStruct):
def __init__(self, _io, _parent=None, _root=None):
super(Id3v24.U2beSynchsafe, self).__init__(_io)
self._parent = _parent
self._root = _root
self._read()
def _read(self):
self.byte0 = Id3v24.U1beSynchsafe(self._io, self, self._root)
self.byte1 = Id3v24.U1beSynchsafe(self._io, self, self._root)
def _fetch_instances(self):
pass
self.byte0._fetch_instances()
self.byte1._fetch_instances()
@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 U4beSynchsafe(KaitaiStruct):
def __init__(self, _io, _parent=None, _root=None):
super(Id3v24.U4beSynchsafe, self).__init__(_io)
self._parent = _parent
self._root = _root
self._read()
def _read(self):
self.short0 = Id3v24.U2beSynchsafe(self._io, self, self._root)
self.short1 = Id3v24.U2beSynchsafe(self._io, self, self._root)
def _fetch_instances(self):
pass
self.short0._fetch_instances()
self.short1._fetch_instances()
@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)