def createFields(self):
yield Bits(self, "start_length", 5)
length = self["start_length"].value
lengths = []
for i in xrange(self.symbols):
while True:
bit = Bit(self, "change_length[%i][]" % i,
"Should the length be changed for symbol %i?" % i)
yield bit
if not bit.value:
break
else:
bit = Enum(
Bit(self, "length_decrement[%i][]" % i,
"Decrement the value?"), {
True: "Decrement",
False: "Increment"
})
yield bit
if bit.value:
length -= 1
else:
length += 1
lengths.append(length)
self.final_length = length
self.tree = build_tree(lengths)
def createFields(self):
for i in xrange(20):
yield Bits(self, "pretree_lengths[]", 4)
pre_tree = build_tree(
[self['pretree_lengths[%d]' % x].value for x in xrange(20)])
if not hasattr(self.root, "lzx_tree_lengths_" + self.name):
self.lengths = [0] * self.num_elements
setattr(self.root, "lzx_tree_lengths_" + self.name, self.lengths)
else:
self.lengths = getattr(self.root, "lzx_tree_lengths_" + self.name)
i = 0
while i < self.num_elements:
field = HuffmanCode(self, "tree_code[]", pre_tree)
if field.realvalue <= 16:
self.lengths[i] = (self.lengths[i] - field.realvalue) % 17
field._description = "Literal tree delta length %i (new length value %i for element %i)" % (
field.realvalue, self.lengths[i], i)
i += 1
yield field
elif field.realvalue == 17:
field._description = "Tree Code 17: Zeros for 4-19 elements"
yield field
extra = Bits(self, "extra[]", 4)
zeros = 4 + extra.value
extra._description = "Extra bits: zeros for %i elements (elements %i through %i)" % (
zeros, i, i + zeros - 1)
yield extra
self.lengths[i:i + zeros] = [0] * zeros
i += zeros
elif field.realvalue == 18:
field._description = "Tree Code 18: Zeros for 20-51 elements"
yield field
extra = Bits(self, "extra[]", 5)
zeros = 20 + extra.value
extra._description = "Extra bits: zeros for %i elements (elements %i through %i)" % (
zeros, i, i + zeros - 1)
yield extra
self.lengths[i:i + zeros] = [0] * zeros
i += zeros
elif field.realvalue == 19:
field._description = "Tree Code 19: Same code for 4-5 elements"
yield field
extra = Bits(self, "extra[]", 1)
run = 4 + extra.value
extra._description = "Extra bits: run for %i elements (elements %i through %i)" % (
run, i, i + run - 1)
yield extra
newfield = HuffmanCode(self, "tree_code[]", pre_tree)
assert newfield.realvalue <= 16
newfield._description = "Literal tree delta length %i (new length value %i for elements %i through %i)" % (
newfield.realvalue, self.lengths[i], i, i + run - 1)
self.lengths[i:i + run] = [
(self.lengths[i] - newfield.realvalue) % 17
] * run
i += run
yield newfield
def createFields(self):
for i in xrange(20):
yield Bits(self, "pretree_lengths[]", 4)
pre_tree = build_tree([self['pretree_lengths[%d]'%x].value for x in xrange(20)])
if not hasattr(self.root, "lzx_tree_lengths_"+self.name):
self.lengths = [0] * self.num_elements
setattr(self.root, "lzx_tree_lengths_"+self.name, self.lengths)
else:
self.lengths = getattr(self.root, "lzx_tree_lengths_"+self.name)
i = 0
while i < self.num_elements:
field = HuffmanCode(self, "tree_code[]", pre_tree)
if field.realvalue <= 16:
self.lengths[i] = (self.lengths[i] - field.realvalue) % 17
field._description = "Literal tree delta length %i (new length value %i for element %i)" % (
field.realvalue, self.lengths[i], i)
i += 1
yield field
elif field.realvalue == 17:
field._description = "Tree Code 17: Zeros for 4-19 elements"
yield field
extra = Bits(self, "extra[]", 4)
zeros = 4 + extra.value
extra._description = "Extra bits: zeros for %i elements (elements %i through %i)" % (zeros, i, i+zeros-1)
yield extra
self.lengths[i:i+zeros] = [0] * zeros
i += zeros
elif field.realvalue == 18:
field._description = "Tree Code 18: Zeros for 20-51 elements"
yield field
extra = Bits(self, "extra[]", 5)
zeros = 20 + extra.value
extra._description = "Extra bits: zeros for %i elements (elements %i through %i)" % (zeros, i, i+zeros-1)
yield extra
self.lengths[i:i+zeros] = [0] * zeros
i += zeros
elif field.realvalue == 19:
field._description = "Tree Code 19: Same code for 4-5 elements"
yield field
extra = Bits(self, "extra[]", 1)
run = 4 + extra.value
extra._description = "Extra bits: run for %i elements (elements %i through %i)" % (run, i, i+run-1)
yield extra
newfield = HuffmanCode(self, "tree_code[]", pre_tree)
assert newfield.realvalue <= 16
newfield._description = "Literal tree delta length %i (new length value %i for elements %i through %i)" % (
newfield.realvalue, self.lengths[i], i, i+run-1)
self.lengths[i:i+run] = [(self.lengths[i] - newfield.realvalue) % 17] * run
i += run
yield newfield
def createFields(self):
# http://www.w3.org/Graphics/JPEG/itu-t81.pdf, page 40-41
yield Enum(Bits(self, "table_class", 4, "Table class"), {
0:"DC or Lossless Table",
1:"AC Table"})
yield Bits(self, "index", 4, "Huffman table destination identifier")
for i in xrange(1, 17):
yield UInt8(self, "count[%i]" % i, "Number of codes of length %i" % i)
lengths = []
remap = {}
for i in xrange(1, 17):
for j in xrange(self["count[%i]" % i].value):
field = UInt8(self, "value[%i][%i]" % (i, j), "Value of code #%i of length %i" % (j, i))
yield field
remap[len(lengths)] = field.value
lengths.append(i)
self.tree = {}
for i,j in build_tree(lengths).iteritems():
self.tree[i] = remap[j]
def createFields(self):
yield Bits(self, "start_length", 5)
length = self["start_length"].value
lengths = []
for i in xrange(self.symbols):
while True:
bit = Bit(self, "change_length[%i][]"%i, "Should the length be changed for symbol %i?"%i)
yield bit
if not bit.value:
break
else:
bit = Enum(Bit(self, "length_decrement[%i][]"%i, "Decrement the value?"), {True: "Decrement", False: "Increment"})
yield bit
if bit.value:
length -= 1
else:
length += 1
lengths.append(length)
self.final_length = length
self.tree = build_tree(lengths)
def createFields(self):
yield Bits(self, "block_type", 3)
yield Bits(self, "block_size", 24)
self.uncompressed_size = self["block_size"].value
self.compression_level = self.root.compr_level
self.window_size = self.WINDOW_SIZE[self.compression_level]
self.block_type = self["block_type"].value
curlen = len(self.parent.uncompressed_data)
if self.block_type in (1, 2): # Verbatim or aligned offset block
if self.block_type == 2:
for i in xrange(8):
yield Bits(self, "aligned_len[]", 3)
aligned_tree = build_tree([self['aligned_len[%d]'%i].value for i in xrange(8)])
yield LZXPreTreeEncodedTree(self, "main_tree_start", 256)
yield LZXPreTreeEncodedTree(self, "main_tree_rest", self.window_size * 8)
main_tree = build_tree(self["main_tree_start"].lengths + self["main_tree_rest"].lengths)
yield LZXPreTreeEncodedTree(self, "length_tree", 249)
length_tree = build_tree(self["length_tree"].lengths)
current_decoded_size = 0
while current_decoded_size < self.uncompressed_size:
if (curlen+current_decoded_size) % 32768 == 0 and (curlen+current_decoded_size) != 0:
padding = paddingSize(self.address + self.current_size, 16)
if padding:
yield PaddingBits(self, "padding[]", padding)
field = HuffmanCode(self, "main_code[]", main_tree)
if field.realvalue < 256:
field._description = "Literal value %r" % chr(field.realvalue)
current_decoded_size += 1
self.parent.uncompressed_data += chr(field.realvalue)
yield field
continue
position_header, length_header = divmod(field.realvalue - 256, 8)
info = self.POSITION_SLOTS[position_header]
if info[2] == 0:
if info[0] == 0:
position = self.parent.r0
field._description = "Position Slot %i, Position [R0] (%i)" % (position_header, position)
elif info[0] == 1:
position = self.parent.r1
self.parent.r1 = self.parent.r0
self.parent.r0 = position
field._description = "Position Slot %i, Position [R1] (%i)" % (position_header, position)
elif info[0] == 2:
position = self.parent.r2
self.parent.r2 = self.parent.r0
self.parent.r0 = position
field._description = "Position Slot %i, Position [R2] (%i)" % (position_header, position)
else:
position = info[0] - 2
self.parent.r2 = self.parent.r1
self.parent.r1 = self.parent.r0
self.parent.r0 = position
field._description = "Position Slot %i, Position %i" % (position_header, position)
else:
field._description = "Position Slot %i, Positions %i to %i" % (position_header, info[0] - 2, info[1] - 2)
if length_header == 7:
field._description += ", Length Values 9 and up"
yield field
length_field = HuffmanCode(self, "length_code[]", length_tree)
length = length_field.realvalue + 9
length_field._description = "Length Code %i, total length %i" % (length_field.realvalue, length)
yield length_field
else:
field._description += ", Length Value %i (Huffman Code %i)"%(length_header + 2, field.value)
yield field
length = length_header + 2
if info[2]:
if self.block_type == 1 or info[2] < 3: # verbatim
extrafield = Bits(self, "position_extra[%s" % field.name.split('[')[1], info[2])
position = extrafield.value + info[0] - 2
extrafield._description = "Position Extra Bits (%i), total position %i"%(extrafield.value, position)
yield extrafield
else: # aligned offset
position = info[0] - 2
if info[2] > 3:
extrafield = Bits(self, "position_verbatim[%s" % field.name.split('[')[1], info[2]-3)
position += extrafield.value*8
extrafield._description = "Position Verbatim Bits (%i), added position %i"%(extrafield.value, extrafield.value*8)
yield extrafield
if info[2] >= 3:
extrafield = HuffmanCode(self, "position_aligned[%s" % field.name.split('[')[1], aligned_tree)
position += extrafield.realvalue
extrafield._description = "Position Aligned Bits (%i), total position %i"%(extrafield.realvalue, position)
yield extrafield
self.parent.r2 = self.parent.r1
self.parent.r1 = self.parent.r0
self.parent.r0 = position
self.parent.uncompressed_data = extend_data(self.parent.uncompressed_data, length, position)
current_decoded_size += length
elif self.block_type == 3: # Uncompressed block
padding = paddingSize(self.address + self.current_size, 16)
if padding:
yield PaddingBits(self, "padding[]", padding)
else:
yield PaddingBits(self, "padding[]", 16)
self.endian = LITTLE_ENDIAN
yield UInt32(self, "r[]", "New value of R0")
yield UInt32(self, "r[]", "New value of R1")
yield UInt32(self, "r[]", "New value of R2")
self.parent.r0 = self["r[0]"].value
self.parent.r1 = self["r[1]"].value
self.parent.r2 = self["r[2]"].value
yield RawBytes(self, "data", self.uncompressed_size)
self.parent.uncompressed_data+=self["data"].value
if self["block_size"].value % 2:
yield PaddingBits(self, "padding", 8)
else:
raise ParserError("Unknown block type %d!"%self.block_type)
def createFields(self):
yield Bits(self, "block_type", 3)
yield Bits(self, "block_size", 24)
self.uncompressed_size = self["block_size"].value
self.compression_level = self.root.compr_level
self.window_size = self.WINDOW_SIZE[self.compression_level]
self.block_type = self["block_type"].value
curlen = len(self.parent.uncompressed_data)
if self.block_type in (1, 2): # Verbatim or aligned offset block
if self.block_type == 2:
for i in xrange(8):
yield Bits(self, "aligned_len[]", 3)
aligned_tree = build_tree(
[self['aligned_len[%d]' % i].value for i in xrange(8)])
yield LZXPreTreeEncodedTree(self, "main_tree_start", 256)
yield LZXPreTreeEncodedTree(self, "main_tree_rest",
self.window_size * 8)
main_tree = build_tree(self["main_tree_start"].lengths +
self["main_tree_rest"].lengths)
yield LZXPreTreeEncodedTree(self, "length_tree", 249)
length_tree = build_tree(self["length_tree"].lengths)
current_decoded_size = 0
while current_decoded_size < self.uncompressed_size:
if (curlen + current_decoded_size) % 32768 == 0 and (
curlen + current_decoded_size) != 0:
padding = paddingSize(self.address + self.current_size, 16)
if padding:
yield PaddingBits(self, "padding[]", padding)
field = HuffmanCode(self, "main_code[]", main_tree)
if field.realvalue < 256:
field._description = "Literal value %r" % chr(
field.realvalue)
current_decoded_size += 1
self.parent.uncompressed_data += chr(field.realvalue)
yield field
continue
position_header, length_header = divmod(
field.realvalue - 256, 8)
info = self.POSITION_SLOTS[position_header]
if info[2] == 0:
if info[0] == 0:
position = self.parent.r0
field._description = "Position Slot %i, Position [R0] (%i)" % (
position_header, position)
elif info[0] == 1:
position = self.parent.r1
self.parent.r1 = self.parent.r0
self.parent.r0 = position
field._description = "Position Slot %i, Position [R1] (%i)" % (
position_header, position)
elif info[0] == 2:
position = self.parent.r2
self.parent.r2 = self.parent.r0
self.parent.r0 = position
field._description = "Position Slot %i, Position [R2] (%i)" % (
position_header, position)
else:
position = info[0] - 2
self.parent.r2 = self.parent.r1
self.parent.r1 = self.parent.r0
self.parent.r0 = position
field._description = "Position Slot %i, Position %i" % (
position_header, position)
else:
field._description = "Position Slot %i, Positions %i to %i" % (
position_header, info[0] - 2, info[1] - 2)
if length_header == 7:
field._description += ", Length Values 9 and up"
yield field
length_field = HuffmanCode(self, "length_code[]",
length_tree)
length = length_field.realvalue + 9
length_field._description = "Length Code %i, total length %i" % (
length_field.realvalue, length)
yield length_field
else:
field._description += ", Length Value %i (Huffman Code %i)" % (
length_header + 2, field.value)
yield field
length = length_header + 2
if info[2]:
if self.block_type == 1 or info[2] < 3: # verbatim
extrafield = Bits(
self,
"position_extra[%s" % field.name.split('[')[1],
info[2])
position = extrafield.value + info[0] - 2
extrafield._description = "Position Extra Bits (%i), total position %i" % (
extrafield.value, position)
yield extrafield
else: # aligned offset
position = info[0] - 2
if info[2] > 3:
extrafield = Bits(
self, "position_verbatim[%s" %
field.name.split('[')[1], info[2] - 3)
position += extrafield.value * 8
extrafield._description = "Position Verbatim Bits (%i), added position %i" % (
extrafield.value, extrafield.value * 8)
yield extrafield
if info[2] >= 3:
extrafield = HuffmanCode(
self, "position_aligned[%s" %
field.name.split('[')[1], aligned_tree)
position += extrafield.realvalue
extrafield._description = "Position Aligned Bits (%i), total position %i" % (
extrafield.realvalue, position)
yield extrafield
self.parent.r2 = self.parent.r1
self.parent.r1 = self.parent.r0
self.parent.r0 = position
self.parent.uncompressed_data = extend_data(
self.parent.uncompressed_data, length, position)
current_decoded_size += length
elif self.block_type == 3: # Uncompressed block
padding = paddingSize(self.address + self.current_size, 16)
if padding:
yield PaddingBits(self, "padding[]", padding)
else:
yield PaddingBits(self, "padding[]", 16)
self.endian = LITTLE_ENDIAN
yield UInt32(self, "r[]", "New value of R0")
yield UInt32(self, "r[]", "New value of R1")
yield UInt32(self, "r[]", "New value of R2")
self.parent.r0 = self["r[0]"].value
self.parent.r1 = self["r[1]"].value
self.parent.r2 = self["r[2]"].value
yield RawBytes(self, "data", self.uncompressed_size)
self.parent.uncompressed_data += self["data"].value
if self["block_size"].value % 2:
yield PaddingBits(self, "padding", 8)
else:
raise ParserError("Unknown block type %d!" % self.block_type)
