nzbToMedia/libs/mutagen/wavpack.py
Labrys 1111074dc3 Update beets to 1.3.18:
Dependencies:
* PyYAML 3.11
* Unidecode 0.4.19
* beets 1.3.18
* colorama 0.3.7
* enum34 1.1.6
* jellyfish 0.5.4
* munkres 1.0.7
* musicbrainzngs 0.6
* mutagen 1.32
2016-06-06 12:08:52 -04:00

126 lines
3.8 KiB
Python

# -*- coding: utf-8 -*-
# Copyright 2006 Joe Wreschnig
# 2014 Christoph Reiter
#
# This program is free software; you can redistribute it and/or modify
# it under the terms of the GNU General Public License version 2 as
# published by the Free Software Foundation.
"""WavPack reading and writing.
WavPack is a lossless format that uses APEv2 tags. Read
* http://www.wavpack.com/
* http://www.wavpack.com/file_format.txt
for more information.
"""
__all__ = ["WavPack", "Open", "delete"]
from mutagen import StreamInfo
from mutagen.apev2 import APEv2File, error, delete
from mutagen._util import cdata
class WavPackHeaderError(error):
pass
RATES = [6000, 8000, 9600, 11025, 12000, 16000, 22050, 24000, 32000, 44100,
48000, 64000, 88200, 96000, 192000]
class _WavPackHeader(object):
def __init__(self, block_size, version, track_no, index_no, total_samples,
block_index, block_samples, flags, crc):
self.block_size = block_size
self.version = version
self.track_no = track_no
self.index_no = index_no
self.total_samples = total_samples
self.block_index = block_index
self.block_samples = block_samples
self.flags = flags
self.crc = crc
@classmethod
def from_fileobj(cls, fileobj):
"""A new _WavPackHeader or raises WavPackHeaderError"""
header = fileobj.read(32)
if len(header) != 32 or not header.startswith(b"wvpk"):
raise WavPackHeaderError("not a WavPack header: %r" % header)
block_size = cdata.uint_le(header[4:8])
version = cdata.ushort_le(header[8:10])
track_no = ord(header[10:11])
index_no = ord(header[11:12])
samples = cdata.uint_le(header[12:16])
if samples == 2 ** 32 - 1:
samples = -1
block_index = cdata.uint_le(header[16:20])
block_samples = cdata.uint_le(header[20:24])
flags = cdata.uint_le(header[24:28])
crc = cdata.uint_le(header[28:32])
return _WavPackHeader(block_size, version, track_no, index_no,
samples, block_index, block_samples, flags, crc)
class WavPackInfo(StreamInfo):
"""WavPack stream information.
Attributes:
* channels - number of audio channels (1 or 2)
* length - file length in seconds, as a float
* sample_rate - audio sampling rate in Hz
* version - WavPack stream version
"""
def __init__(self, fileobj):
try:
header = _WavPackHeader.from_fileobj(fileobj)
except WavPackHeaderError:
raise WavPackHeaderError("not a WavPack file")
self.version = header.version
self.channels = bool(header.flags & 4) or 2
self.sample_rate = RATES[(header.flags >> 23) & 0xF]
if header.total_samples == -1 or header.block_index != 0:
# TODO: we could make this faster by using the tag size
# and search backwards for the last block, then do
# last.block_index + last.block_samples - initial.block_index
samples = header.block_samples
while 1:
fileobj.seek(header.block_size - 32 + 8, 1)
try:
header = _WavPackHeader.from_fileobj(fileobj)
except WavPackHeaderError:
break
samples += header.block_samples
else:
samples = header.total_samples
self.length = float(samples) / self.sample_rate
def pprint(self):
return u"WavPack, %.2f seconds, %d Hz" % (self.length,
self.sample_rate)
class WavPack(APEv2File):
_Info = WavPackInfo
_mimes = ["audio/x-wavpack"]
@staticmethod
def score(filename, fileobj, header):
return header.startswith(b"wvpk") * 2
Open = WavPack