Allegro library for C (mostly used for game and multimedia apps programming) used its own container file format.
In general, it allows storage of arbitrary binary data blocks bundled together with some simple key-value style metadata ("properties") for every block. Allegro also pre-defines some simple formats for bitmaps, fonts, MIDI music, sound samples and palettes. Allegro library v4.0+ also support LZSS compression.
This spec applies to Allegro data files for library versions 2.2 up to 4.4.
This page hosts a formal specification of Allegro data file 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 = AllegroDat.from_file("path/to/local/file.dat")
Or parse structure from a bytes:
from kaitaistruct import KaitaiStream, BytesIO
raw = b"\x00\x01\x02..."
data = AllegroDat(KaitaiStream(BytesIO(raw)))
After that, one can get various attributes from the structure by invoking getter methods like:
data.pack_magic # => get pack magic
# 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
from enum import Enum
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 AllegroDat(KaitaiStruct):
"""Allegro library for C (mostly used for game and multimedia apps
programming) used its own container file format.
In general, it allows storage of arbitrary binary data blocks
bundled together with some simple key-value style metadata
("properties") for every block. Allegro also pre-defines some simple
formats for bitmaps, fonts, MIDI music, sound samples and
palettes. Allegro library v4.0+ also support LZSS compression.
This spec applies to Allegro data files for library versions 2.2 up
to 4.4.
.. seealso::
Source - https://liballeg.org/stabledocs/en/datafile.html
"""
class PackEnum(Enum):
unpacked = 1936484398
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.pack_magic = KaitaiStream.resolve_enum(AllegroDat.PackEnum, self._io.read_u4be())
self.dat_magic = self._io.read_bytes(4)
if not self.dat_magic == b"\x41\x4C\x4C\x2E":
raise kaitaistruct.ValidationNotEqualError(b"\x41\x4C\x4C\x2E", self.dat_magic, self._io, u"/seq/1")
self.num_objects = self._io.read_u4be()
self.objects = []
for i in range(self.num_objects):
self.objects.append(AllegroDat.DatObject(self._io, self, self._root))
class DatFont16(KaitaiStruct):
"""Simple monochrome monospaced font, 95 characters, 8x16 px
characters.
"""
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.chars = []
for i in range(95):
self.chars.append(self._io.read_bytes(16))
class DatBitmap(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.bits_per_pixel = self._io.read_s2be()
self.width = self._io.read_u2be()
self.height = self._io.read_u2be()
self.image = self._io.read_bytes_full()
class DatFont(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.font_size = self._io.read_s2be()
_on = self.font_size
if _on == 8:
self.body = AllegroDat.DatFont8(self._io, self, self._root)
elif _on == 16:
self.body = AllegroDat.DatFont16(self._io, self, self._root)
elif _on == 0:
self.body = AllegroDat.DatFont39(self._io, self, self._root)
class DatFont8(KaitaiStruct):
"""Simple monochrome monospaced font, 95 characters, 8x8 px
characters.
"""
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.chars = []
for i in range(95):
self.chars.append(self._io.read_bytes(8))
class DatObject(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.properties = []
i = 0
while True:
_ = AllegroDat.Property(self._io, self, self._root)
self.properties.append(_)
if not (_.is_valid):
break
i += 1
self.len_compressed = self._io.read_s4be()
self.len_uncompressed = self._io.read_s4be()
_on = self.type
if _on == u"BMP ":
self._raw_body = self._io.read_bytes(self.len_compressed)
_io__raw_body = KaitaiStream(BytesIO(self._raw_body))
self.body = AllegroDat.DatBitmap(_io__raw_body, self, self._root)
elif _on == u"RLE ":
self._raw_body = self._io.read_bytes(self.len_compressed)
_io__raw_body = KaitaiStream(BytesIO(self._raw_body))
self.body = AllegroDat.DatRleSprite(_io__raw_body, self, self._root)
elif _on == u"FONT":
self._raw_body = self._io.read_bytes(self.len_compressed)
_io__raw_body = KaitaiStream(BytesIO(self._raw_body))
self.body = AllegroDat.DatFont(_io__raw_body, self, self._root)
else:
self.body = self._io.read_bytes(self.len_compressed)
@property
def type(self):
if hasattr(self, '_m_type'):
return self._m_type
self._m_type = self.properties[-1].magic
return getattr(self, '_m_type', None)
class DatFont39(KaitaiStruct):
"""New bitmap font format introduced since Allegro 3.9: allows
flexible designation of character ranges, 8-bit colored
characters, etc.
"""
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.num_ranges = self._io.read_s2be()
self.ranges = []
for i in range(self.num_ranges):
self.ranges.append(AllegroDat.DatFont39.Range(self._io, self, self._root))
class Range(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.mono = self._io.read_u1()
self.start_char = self._io.read_u4be()
self.end_char = self._io.read_u4be()
self.chars = []
for i in range(((self.end_char - self.start_char) + 1)):
self.chars.append(AllegroDat.DatFont39.FontChar(self._io, self, self._root))
class FontChar(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.width = self._io.read_u2be()
self.height = self._io.read_u2be()
self.body = self._io.read_bytes((self.width * self.height))
class Property(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.magic = (self._io.read_bytes(4)).decode(u"UTF-8")
if self.is_valid:
self.type = (self._io.read_bytes(4)).decode(u"UTF-8")
if self.is_valid:
self.len_body = self._io.read_u4be()
if self.is_valid:
self.body = (self._io.read_bytes(self.len_body)).decode(u"UTF-8")
@property
def is_valid(self):
if hasattr(self, '_m_is_valid'):
return self._m_is_valid
self._m_is_valid = self.magic == u"prop"
return getattr(self, '_m_is_valid', None)
class DatRleSprite(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.bits_per_pixel = self._io.read_s2be()
self.width = self._io.read_u2be()
self.height = self._io.read_u2be()
self.len_image = self._io.read_u4be()
self.image = self._io.read_bytes_full()