mpv/TOOLS/matroska.py

430 lines
14 KiB
Python
Executable File

#!/usr/bin/env python
"""
Generate C definitions for parsing Matroska files.
Can also be used to directly parse Matroska files and display their contents.
"""
#
# This file is part of MPlayer.
#
# MPlayer is free software; you can redistribute it and/or modify
# it under the terms of the GNU General Public License as published by
# the Free Software Foundation; either version 2 of the License, or
# (at your option) any later version.
#
# MPlayer is distributed in the hope that it will be useful,
# but WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
# GNU General Public License for more details.
#
# You should have received a copy of the GNU General Public License along
# with MPlayer; if not, write to the Free Software Foundation, Inc.,
# 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
#
# for compatibility with Python 2.x
from __future__ import print_function
elements_ebml = (
'EBML, 1a45dfa3, sub', (
'EBMLVersion, 4286, uint',
'EBMLReadVersion, 42f7, uint',
'EBMLMaxIDLength, 42f2, uint',
'EBMLMaxSizeLength, 42f3, uint',
'DocType, 4282, str',
'DocTypeVersion, 4287, uint',
'DocTypeReadVersion, 4285, uint',
),
'CRC32, bf, binary',
'Void, ec, binary',
)
elements_matroska = (
'Segment, 18538067, sub', (
'SeekHead*, 114d9b74, sub', (
'Seek*, 4dbb, sub', (
'SeekID, 53ab, ebml_id',
'SeekPosition, 53ac, uint',
),
),
'Info*, 1549a966, sub', (
'SegmentUID, 73a4, binary',
'PrevUID, 3cb923, binary',
'NextUID, 3eb923, binary',
'TimecodeScale, 2ad7b1, uint',
'DateUTC, 4461, sint',
'Title, 7ba9, str',
'MuxingApp, 4d80, str',
'WritingApp, 5741, str',
'Duration, 4489, float',
),
'Cluster*, 1f43b675, sub', (
'Timecode, e7, uint',
'BlockGroup*, a0, sub', (
'Block, a1, binary',
'BlockDuration, 9b, uint',
'ReferenceBlock*, fb, sint',
),
'SimpleBlock*, a3, binary',
),
'Tracks*, 1654ae6b, sub', (
'TrackEntry*, ae, sub', (
'TrackNumber, d7, uint',
'TrackUID, 73c5, uint',
'TrackType, 83, uint',
'FlagEnabled, b9, uint',
'FlagDefault, 88, uint',
'FlagForced, 55aa, uint',
'FlagLacing, 9c, uint',
'MinCache, 6de7, uint',
'MaxCache, 6df8, uint',
'DefaultDuration, 23e383, uint',
'TrackTimecodeScale, 23314f, float',
'MaxBlockAdditionID, 55ee, uint',
'Name, 536e, str',
'Language, 22b59c, str',
'CodecID, 86, str',
'CodecPrivate, 63a2, binary',
'CodecName, 258688, str',
'CodecDecodeAll, aa, uint',
'Video, e0, sub', (
'FlagInterlaced, 9a, uint',
'PixelWidth, b0, uint',
'PixelHeight, ba, uint',
'DisplayWidth, 54b0, uint',
'DisplayHeight, 54ba, uint',
'DisplayUnit, 54b2, uint',
'FrameRate, 2383e3, float',
),
'Audio, e1, sub', (
'SamplingFrequency, b5, float',
'OutputSamplingFrequency, 78b5, float',
'Channels, 9f, uint',
'BitDepth, 6264, uint',
),
'ContentEncodings, 6d80, sub', (
'ContentEncoding*, 6240, sub', (
'ContentEncodingOrder, 5031, uint',
'ContentEncodingScope, 5032, uint',
'ContentEncodingType, 5033, uint',
'ContentCompression, 5034, sub', (
'ContentCompAlgo, 4254, uint',
'ContentCompSettings, 4255, binary',
),
),
),
),
),
'Cues, 1c53bb6b, sub', (
'CuePoint*, bb, sub', (
'CueTime, b3, uint',
'CueTrackPositions*, b7, sub', (
'CueTrack, f7, uint',
'CueClusterPosition, f1, uint',
),
),
),
'Attachments, 1941a469, sub', (
'AttachedFile*, 61a7, sub', (
'FileDescription, 467e, str',
'FileName, 466e, str',
'FileMimeType, 4660, str',
'FileData, 465c, binary',
'FileUID, 46ae, uint',
),
),
'Chapters, 1043a770, sub', (
'EditionEntry*, 45b9, sub', (
'EditionUID, 45bc, uint',
'EditionFlagHidden, 45bd, uint',
'EditionFlagDefault, 45db, uint',
'EditionFlagOrdered, 45dd, uint',
'ChapterAtom*, b6, sub', (
'ChapterUID, 73c4, uint',
'ChapterTimeStart, 91, uint',
'ChapterTimeEnd, 92, uint',
'ChapterFlagHidden, 98, uint',
'ChapterFlagEnabled, 4598, uint',
'ChapterSegmentUID, 6e67, binary',
'ChapterSegmentEditionUID, 6ebc, uint',
'ChapterDisplay*, 80, sub', (
'ChapString, 85, str',
'ChapLanguage*, 437c, str',
'ChapCountry*, 437e, str',
),
),
),
),
'Tags*, 1254c367, sub', (
'Tag*, 7373, sub', (
'Targets, 63c0, sub', (
'TargetTypeValue, 68ca, uint',
'TargetTrackUID, 63c5, uint',
'TargetEditionUID, 63c9, uint',
'TargetChapterUID, 63c4, uint',
'TargetAttachmentUID, 63c6, uint',
),
'SimpleTag*, 67c8, sub', (
'TagName, 45a3, str',
'TagLanguage, 447a, str',
'TagString, 4487, str'
),
),
),
),
)
import sys
from math import ldexp
from binascii import hexlify
def byte2num(s):
return int(hexlify(s), 16)
class EOF(Exception): pass
def camelcase_to_words(name):
parts = []
start = 0
for i in range(1, len(name)):
if name[i].isupper() and (name[i-1].islower() or
name[i+1:i+2].islower()):
parts.append(name[start:i])
start = i
parts.append(name[start:])
return '_'.join(parts).lower()
class MatroskaElement(object):
def __init__(self, name, elid, valtype, namespace):
self.name = name
self.definename = '{0}_ID_{1}'.format(namespace, name.upper())
self.fieldname = camelcase_to_words(name)
self.structname = 'ebml_' + self.fieldname
self.elid = elid
self.valtype = valtype
if valtype == 'sub':
self.ebmltype = 'EBML_TYPE_SUBELEMENTS'
self.valname = 'struct ' + self.structname
else:
self.ebmltype = 'EBML_TYPE_' + valtype.upper()
try:
self.valname = {'uint': 'uint64_t', 'str': 'struct bstr',
'binary': 'struct bstr', 'ebml_id': 'uint32_t',
'float': 'double', 'sint': 'int64_t',
}[valtype]
except KeyError:
raise SyntaxError('Unrecognized value type ' + valtype)
self.subelements = ()
def add_subelements(self, subelements):
self.subelements = subelements
self.subids = set(x[0].elid for x in subelements)
elementd = {}
elementlist = []
def parse_elems(l, namespace):
subelements = []
for el in l:
if isinstance(el, str):
name, hexid, eltype = [x.strip() for x in el.split(',')]
multiple = name.endswith('*')
name = name.strip('*')
new = MatroskaElement(name, hexid, eltype, namespace)
elementd[hexid] = new
elementlist.append(new)
subelements.append((new, multiple))
else:
new.add_subelements(parse_elems(el, namespace))
return subelements
parse_elems(elements_ebml, 'EBML')
parse_elems(elements_matroska, 'MATROSKA')
def generate_C_header():
print('// Generated by TOOLS/matroska.py, do not edit manually')
print()
for el in elementlist:
print('#define {0.definename:40} 0x{0.elid}'.format(el))
print()
for el in reversed(elementlist):
if not el.subelements:
continue
print()
print('struct {0.structname} {{'.format(el))
l = max(len(subel.valname) for subel, multiple in el.subelements)+1
for subel, multiple in el.subelements:
print(' {e.valname:{l}} {star}{e.fieldname};'.format(
e=subel, l=l, star=' *'[multiple]))
print()
for subel, multiple in el.subelements:
print(' int n_{0.fieldname};'.format(subel))
print('};')
for el in elementlist:
if not el.subelements:
continue
print('extern const struct ebml_elem_desc {0.structname}_desc;'.format(
el))
print()
print('#define MAX_EBML_SUBELEMENTS', max(len(el.subelements)
for el in elementlist))
def generate_C_definitions():
print('// Generated by TOOLS/matroska.py, do not edit manually')
print()
for el in reversed(elementlist):
print()
if el.subelements:
print('#define N', el.fieldname)
print('E_S("{0}", {1})'.format(el.name, len(el.subelements)))
for subel, multiple in el.subelements:
print('F({0.definename}, {0.fieldname}, {1})'.format(
subel, int(multiple)))
print('}};')
print('#undef N')
else:
print('E("{0.name}", {0.fieldname}, {0.ebmltype})'.format(el))
def read(s, length):
t = s.read(length)
if len(t) != length:
raise EOF
return t
def read_id(s):
t = read(s, 1)
i = 0
mask = 128
if ord(t) == 0:
raise SyntaxError
while not ord(t) & mask:
i += 1
mask >>= 1
t += read(s, i)
return t
def read_vint(s):
t = read(s, 1)
i = 0
mask = 128
if ord(t) == 0:
raise SyntaxError
while not ord(t) & mask:
i += 1
mask >>= 1
t = bytes((ord(t) & (mask - 1),))
t += read(s, i)
return i+1, byte2num(t)
def read_str(s, length):
return read(s, length)
def read_uint(s, length):
t = read(s, length)
return byte2num(t)
def read_sint(s, length):
i = read_uint(s, length)
mask = 1 << (length * 8 - 1)
if i & mask:
i -= 2 * mask
return i
def read_float(s, length):
t = read(s, length)
i = byte2num(t)
if length == 4:
f = ldexp((i & 0x7fffff) + (1 << 23), (i >> 23 & 0xff) - 150)
if i & (1 << 31):
f = -f
elif length == 8:
f = ldexp((i & ((1 << 52) - 1)) + (1 << 52), (i >> 52 & 0x7ff) - 1075)
if i & (1 << 63):
f = -f
else:
raise SyntaxError
return f
def parse_one(s, depth, parent, maxlen):
elid = hexlify(read_id(s)).decode('ascii')
elem = elementd.get(elid)
if parent is not None and elid not in parent.subids and elid not in ('ec', 'bf'):
print('Unexpected:', elid)
if 1:
raise NotImplementedError
size, length = read_vint(s)
this_length = len(elid) / 2 + size + length
if elem is not None:
if elem.valtype != 'skip':
print(depth, elid, elem.name, 'size:', length, 'value:', end=' ')
if elem.valtype == 'sub':
print('subelements:')
while length > 0:
length -= parse_one(s, depth + 1, elem, length)
if length < 0:
raise SyntaxError
elif elem.valtype == 'str':
print('string', repr(read_str(s, length).decode('utf8', 'replace')))
elif elem.valtype in ('binary', 'ebml_id'):
t = read_str(s, length)
dec = ''
if elem.valtype == 'ebml_id':
idelem = elementd.get(hexlify(t).decode('ascii'))
if idelem is None:
dec = '(UNKNOWN)'
else:
dec = '({0.name})'.format(idelem)
if len(t) < 20:
t = hexlify(t).decode('ascii')
else:
t = '<skipped {0} bytes>'.format(len(t))
print('binary', t, dec)
elif elem.valtype == 'uint':
print('uint', read_uint(s, length))
elif elem.valtype == 'sint':
print('sint', read_sint(s, length))
elif elem.valtype == 'float':
print('float', read_float(s, length))
elif elem.valtype == 'skip':
read(s, length)
else:
raise NotImplementedError
else:
print(depth, 'Unknown element:', elid, 'size:', length)
read(s, length)
return this_length
def parse_toplevel(s):
parse_one(s, 0, None, 1 << 63)
if sys.argv[1] == '--generate-header':
generate_C_header()
elif sys.argv[1] == '--generate-definitions':
generate_C_definitions()
else:
s = open(sys.argv[1], "rb")
while 1:
start = s.tell()
try:
parse_toplevel(s)
except EOF:
if s.tell() != start:
raise Exception("Unexpected end of file")
break