def __update_offset_table(self, fileobj, fmt, atom, delta, offset):
"""Update offset table in the specified atom."""
if atom.offset > offset:
atom.offset += delta
fileobj.seek(atom.offset + 12)
data = fileobj.read(atom.length - 12)
fmt = fmt % cdata.uint_be(data[:4])
offsets = struct.unpack(fmt, data[4:])
offsets = [o + (0, delta)[offset < o] for o in offsets]
fileobj.seek(atom.offset + 16)
fileobj.write(struct.pack(fmt, *offsets))
def __update_offset_table(self, fileobj, fmt, atom, delta, offset):
"""Update offset table in the specified atom."""
if atom.offset > offset:
atom.offset += delta
fileobj.seek(atom.offset + 12)
data = fileobj.read(atom.length - 12)
fmt = fmt % cdata.uint_be(data[:4])
offsets = struct.unpack(fmt, data[4:])
offsets = [o + (0, delta)[offset < o] for o in offsets]
fileobj.seek(atom.offset + 16)
fileobj.write(struct.pack(fmt, *offsets))
def parse_full_atom(data):
"""Some atoms are versioned. Split them up in (version, flags, payload).
Can raise ValueError.
"""
if len(data) < 4:
raise ValueError("not enough data")
version = ord(data[0:1])
flags = cdata.uint_be(b"\x00" + data[1:4])
return version, flags, data[4:]
def __update_tfhd(self, fileobj, atom, delta, offset):
if atom.offset > offset:
atom.offset += delta
fileobj.seek(atom.offset + 9)
data = fileobj.read(atom.length - 9)
flags = cdata.uint_be(b"\x00" + data[:3])
if flags & 1:
o = cdata.ulonglong_be(data[7:15])
if o > offset:
o += delta
fileobj.seek(atom.offset + 16)
fileobj.write(cdata.to_ulonglong_be(o))
def __update_tfhd(self, fileobj, atom, delta, offset):
if atom.offset > offset:
atom.offset += delta
fileobj.seek(atom.offset + 9)
data = fileobj.read(atom.length - 9)
flags = cdata.uint_be(b"\x00" + data[:3])
if flags & 1:
o = cdata.ulonglong_be(data[7:15])
if o > offset:
o += delta
fileobj.seek(atom.offset + 16)
fileobj.write(cdata.to_ulonglong_be(o))
def __parse_freeform(self, atom, data):
length = cdata.uint_be(data[:4])
mean = data[12:length]
pos = length
length = cdata.uint_be(data[pos:pos + 4])
name = data[pos + 12:pos + length]
pos += length
value = []
while pos < atom.length - 8:
length, atom_name = struct.unpack(">I4s", data[pos:pos + 8])
if atom_name != b"data":
raise MP4MetadataError(
"unexpected atom %r inside %r" % (atom_name, atom.name))
version = ord(data[pos + 8:pos + 8 + 1])
flags = struct.unpack(">I", b"\x00" + data[pos + 9:pos + 12])[0]
value.append(MP4FreeForm(data[pos + 16:pos + length],
dataformat=flags, version=version))
pos += length
key = _name2key(atom.name + b":" + mean + b":" + name)
self.__add(key, value)
def __parse_freeform(self, atom, data):
length = cdata.uint_be(data[:4])
mean = data[12:length]
pos = length
length = cdata.uint_be(data[pos:pos + 4])
name = data[pos + 12:pos + length]
pos += length
value = []
while pos < atom.length - 8:
length, atom_name = struct.unpack(">I4s", data[pos:pos + 8])
if atom_name != b"data":
raise MP4MetadataError("unexpected atom %r inside %r" %
(atom_name, atom.name))
version = ord(data[pos + 8:pos + 8 + 1])
flags = struct.unpack(">I", b"\x00" + data[pos + 9:pos + 12])[0]
value.append(
MP4FreeForm(data[pos + 16:pos + length],
dataformat=flags,
version=version))
pos += length
key = _name2key(atom.name + b":" + mean + b":" + name)
self.__add(key, value)
def __init__(self, fileobj):
page = OggPage(fileobj)
while not page.packets[0].startswith(b"\x80theora"):
page = OggPage(fileobj)
if not page.first:
raise OggTheoraHeaderError("page has ID header, but doesn't start a stream")
data = page.packets[0]
vmaj, vmin = struct.unpack("2B", data[7:9])
if (vmaj, vmin) != (3, 2):
raise OggTheoraHeaderError("found Theora version %d.%d != 3.2" % (vmaj, vmin))
fps_num, fps_den = struct.unpack(">2I", data[22:30])
self.fps = fps_num / float(fps_den)
self.bitrate = cdata.uint_be(b"\x00" + data[37:40])
self.granule_shift = (cdata.ushort_be(data[40:42]) >> 5) & 0x1F
self.serial = page.serial
def __update_parents(self, fileobj, path, delta):
"""Update all parent atoms with the new size."""
if delta == 0:
return
for atom in path:
fileobj.seek(atom.offset)
size = cdata.uint_be(fileobj.read(4))
if size == 1: # 64bit
# skip name (4B) and read size (8B)
size = cdata.ulonglong_be(fileobj.read(12)[4:])
fileobj.seek(atom.offset + 8)
fileobj.write(cdata.to_ulonglong_be(size + delta))
else: # 32bit
fileobj.seek(atom.offset)
fileobj.write(cdata.to_uint_be(size + delta))
def __init__(self, fileobj):
page = OggPage(fileobj)
while not page.packets[0].startswith(b"\x80theora"):
page = OggPage(fileobj)
if not page.first:
raise OggTheoraHeaderError(
"page has ID header, but doesn't start a stream")
data = page.packets[0]
vmaj, vmin = struct.unpack("2B", data[7:9])
if (vmaj, vmin) != (3, 2):
raise OggTheoraHeaderError("found Theora version %d.%d != 3.2" %
(vmaj, vmin))
fps_num, fps_den = struct.unpack(">2I", data[22:30])
self.fps = fps_num / float(fps_den)
self.bitrate = cdata.uint_be(b"\x00" + data[37:40])
self.granule_shift = (cdata.ushort_be(data[40:42]) >> 5) & 0x1F
self.serial = page.serial
def __update_parents(self, fileobj, path, delta):
"""Update all parent atoms with the new size."""
if delta == 0:
return
for atom in path:
fileobj.seek(atom.offset)
size = cdata.uint_be(fileobj.read(4))
if size == 1: # 64bit
# skip name (4B) and read size (8B)
size = cdata.ulonglong_be(fileobj.read(12)[4:])
fileobj.seek(atom.offset + 8)
fileobj.write(cdata.to_ulonglong_be(size + delta))
else: # 32bit
fileobj.seek(atom.offset)
fileobj.write(cdata.to_uint_be(size + delta))
