Creative Voice File is a container file format for digital audio wave data. Initial revisions were able to support only unsigned 8-bit PCM and ADPCM data, later versions were revised to add support for 16-bit PCM and a-law / u-law formats.
This format was actively used in 1990s, around the advent of Creative's sound cards (Sound Blaster family). It was a popular choice for a digital sound container in lots of games and multimedia software due to simplicity and availability of Creative's recording / editing tools.
This page hosts a formal specification of Creative Voice 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 = CreativeVoiceFile.from_file("path/to/local/file.voc")
Or parse structure from a bytes:
from kaitaistruct import KaitaiStream, BytesIO
raw = b"\x00\x01\x02..."
data = CreativeVoiceFile(KaitaiStream(BytesIO(raw)))
After that, one can get various attributes from the structure by invoking getter methods like:
data.header_size # => Total size of this main header (usually 0x001A)
# 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 CreativeVoiceFile(KaitaiStruct):
"""Creative Voice File is a container file format for digital audio
wave data. Initial revisions were able to support only unsigned
8-bit PCM and ADPCM data, later versions were revised to add support
for 16-bit PCM and a-law / u-law formats.
This format was actively used in 1990s, around the advent of
Creative's sound cards (Sound Blaster family). It was a popular
choice for a digital sound container in lots of games and multimedia
software due to simplicity and availability of Creative's recording
/ editing tools.
.. seealso::
Source - https://wiki.multimedia.cx/index.php?title=Creative_Voice
"""
class BlockTypes(Enum):
terminator = 0
sound_data = 1
sound_data_cont = 2
silence = 3
marker = 4
text = 5
repeat_start = 6
repeat_end = 7
extra_info = 8
sound_data_new = 9
class Codecs(Enum):
pcm_8bit_unsigned = 0
adpcm_4bit = 1
adpcm_2_6bit = 2
adpcm_2_bit = 3
pcm_16bit_signed = 4
alaw = 6
ulaw = 7
adpcm_4_to_16bit = 512
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(20)
if not self.magic == b"\x43\x72\x65\x61\x74\x69\x76\x65\x20\x56\x6F\x69\x63\x65\x20\x46\x69\x6C\x65\x1A":
raise kaitaistruct.ValidationNotEqualError(b"\x43\x72\x65\x61\x74\x69\x76\x65\x20\x56\x6F\x69\x63\x65\x20\x46\x69\x6C\x65\x1A", self.magic, self._io, u"/seq/0")
self.header_size = self._io.read_u2le()
self.version = self._io.read_u2le()
self.checksum = self._io.read_u2le()
self.blocks = []
i = 0
while not self._io.is_eof():
self.blocks.append(CreativeVoiceFile.Block(self._io, self, self._root))
i += 1
class BlockMarker(KaitaiStruct):
"""
.. seealso::
Source - https://wiki.multimedia.cx/index.php?title=Creative_Voice#Block_type_0x04:_Marker
"""
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.marker_id = self._io.read_u2le()
class BlockSilence(KaitaiStruct):
"""
.. seealso::
Source - https://wiki.multimedia.cx/index.php?title=Creative_Voice#Block_type_0x03:_Silence
"""
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.duration_samples = self._io.read_u2le()
self.freq_div = self._io.read_u1()
@property
def sample_rate(self):
if hasattr(self, '_m_sample_rate'):
return self._m_sample_rate
self._m_sample_rate = (1000000.0 / (256 - self.freq_div))
return getattr(self, '_m_sample_rate', None)
@property
def duration_sec(self):
"""Duration of silence, in seconds."""
if hasattr(self, '_m_duration_sec'):
return self._m_duration_sec
self._m_duration_sec = (self.duration_samples / self.sample_rate)
return getattr(self, '_m_duration_sec', None)
class BlockSoundDataNew(KaitaiStruct):
"""
.. seealso::
Source - https://wiki.multimedia.cx/index.php?title=Creative_Voice#Block_type_0x09:_Sound_data_.28New_format.29
"""
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.sample_rate = self._io.read_u4le()
self.bits_per_sample = self._io.read_u1()
self.num_channels = self._io.read_u1()
self.codec = KaitaiStream.resolve_enum(CreativeVoiceFile.Codecs, self._io.read_u2le())
self.reserved = self._io.read_bytes(4)
self.wave = self._io.read_bytes_full()
class Block(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.block_type = KaitaiStream.resolve_enum(CreativeVoiceFile.BlockTypes, self._io.read_u1())
if self.block_type != CreativeVoiceFile.BlockTypes.terminator:
self.body_size1 = self._io.read_u2le()
if self.block_type != CreativeVoiceFile.BlockTypes.terminator:
self.body_size2 = self._io.read_u1()
if self.block_type != CreativeVoiceFile.BlockTypes.terminator:
_on = self.block_type
if _on == CreativeVoiceFile.BlockTypes.sound_data_new:
self._raw_body = self._io.read_bytes(self.body_size)
_io__raw_body = KaitaiStream(BytesIO(self._raw_body))
self.body = CreativeVoiceFile.BlockSoundDataNew(_io__raw_body, self, self._root)
elif _on == CreativeVoiceFile.BlockTypes.repeat_start:
self._raw_body = self._io.read_bytes(self.body_size)
_io__raw_body = KaitaiStream(BytesIO(self._raw_body))
self.body = CreativeVoiceFile.BlockRepeatStart(_io__raw_body, self, self._root)
elif _on == CreativeVoiceFile.BlockTypes.marker:
self._raw_body = self._io.read_bytes(self.body_size)
_io__raw_body = KaitaiStream(BytesIO(self._raw_body))
self.body = CreativeVoiceFile.BlockMarker(_io__raw_body, self, self._root)
elif _on == CreativeVoiceFile.BlockTypes.sound_data:
self._raw_body = self._io.read_bytes(self.body_size)
_io__raw_body = KaitaiStream(BytesIO(self._raw_body))
self.body = CreativeVoiceFile.BlockSoundData(_io__raw_body, self, self._root)
elif _on == CreativeVoiceFile.BlockTypes.extra_info:
self._raw_body = self._io.read_bytes(self.body_size)
_io__raw_body = KaitaiStream(BytesIO(self._raw_body))
self.body = CreativeVoiceFile.BlockExtraInfo(_io__raw_body, self, self._root)
elif _on == CreativeVoiceFile.BlockTypes.silence:
self._raw_body = self._io.read_bytes(self.body_size)
_io__raw_body = KaitaiStream(BytesIO(self._raw_body))
self.body = CreativeVoiceFile.BlockSilence(_io__raw_body, self, self._root)
else:
self.body = self._io.read_bytes(self.body_size)
@property
def body_size(self):
"""body_size is a 24-bit little-endian integer, so we're
emulating that by adding two standard-sized integers
(body_size1 and body_size2).
"""
if hasattr(self, '_m_body_size'):
return self._m_body_size
if self.block_type != CreativeVoiceFile.BlockTypes.terminator:
self._m_body_size = (self.body_size1 + (self.body_size2 << 16))
return getattr(self, '_m_body_size', None)
class BlockRepeatStart(KaitaiStruct):
"""
.. seealso::
Source - https://wiki.multimedia.cx/index.php?title=Creative_Voice#Block_type_0x06:_Repeat_start
"""
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.repeat_count_1 = self._io.read_u2le()
class BlockSoundData(KaitaiStruct):
"""
.. seealso::
Source - https://wiki.multimedia.cx/index.php?title=Creative_Voice#Block_type_0x01:_Sound_data
"""
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.freq_div = self._io.read_u1()
self.codec = KaitaiStream.resolve_enum(CreativeVoiceFile.Codecs, self._io.read_u1())
self.wave = self._io.read_bytes_full()
@property
def sample_rate(self):
if hasattr(self, '_m_sample_rate'):
return self._m_sample_rate
self._m_sample_rate = (1000000.0 / (256 - self.freq_div))
return getattr(self, '_m_sample_rate', None)
class BlockExtraInfo(KaitaiStruct):
"""
.. seealso::
Source - https://wiki.multimedia.cx/index.php?title=Creative_Voice#Block_type_0x08:_Extra_info
"""
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.freq_div = self._io.read_u2le()
self.codec = KaitaiStream.resolve_enum(CreativeVoiceFile.Codecs, self._io.read_u1())
self.num_channels_1 = self._io.read_u1()
@property
def num_channels(self):
"""Number of channels (1 = mono, 2 = stereo)."""
if hasattr(self, '_m_num_channels'):
return self._m_num_channels
self._m_num_channels = (self.num_channels_1 + 1)
return getattr(self, '_m_num_channels', None)
@property
def sample_rate(self):
if hasattr(self, '_m_sample_rate'):
return self._m_sample_rate
self._m_sample_rate = (256000000.0 / (self.num_channels * (65536 - self.freq_div)))
return getattr(self, '_m_sample_rate', None)