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Line 1: − import sys, struct+ − class WiiLZ77:+ − TYPE_LZ77 = 1+ − def __init__(self, file, offset):+ − self.file = file+ − self.offset = offset+ − + − self.file.seek(self.offset)+ − + − hdr = struct.unpack("<I",self.file.read(4))[0]+ − self.uncompressed_length = hdr>>8+ − self.compression_type = hdr>>4 & 0xF+ − + − if self.compression_type != self.TYPE_LZ77:+ − raise ValueError("Unsupported compression method %d"%self.compression_type)+ − + − def uncompress(self):+ − dout = "" + + + + + + + + + + + + + + + + + + + + + + + + + + − self.file.seek(self.offset + 0x4)+ − − while len(dout) < self.uncompressed_length: − flags = struct.unpack("<B",self.file.read(1))[0] − − for i in range(8): − if flags & 0x80: − info = struct.unpack(">H",self.file.read(2))[0] − num = 3 + ((info>>12)&0xF) − disp = info & 0xFFF − ptr = len(dout) - (info & 0xFFF) - 1 − for i in range(num): − dout += dout[ptr] − ptr+=1 − if len(dout) >= self.uncompressed_length: − break − else: − dout += self.file.read(1) − flags <<= 1 − if len(dout) >= self.uncompressed_length: − break − − self.data = dout − return self.data − f = open(sys.argv[1])+ − + − hdr = f.read(4) − if hdr != "LZ77": − unc = WiiLZ77(f, f.tell())+ − du = unc.uncompress()+ − f2 = open(sys.argv[2],"w")+ − f2.write(du)+ − f2.close()+
no edit summary
Many files on the Wii are compressed using the '''LZ77''' compression algorithm. This Python code, by Marcan, will decompress them.
Many files on the Wii are compressed using the '''LZ77''' compression algorithm. This Python code, by Marcan, will decompress them.
<source lang="python">
<source lang="python">
import sys, struct
class WiiLZ77:
TYPE_LZ77 = 1
def __init__(self, file, offset):
self.file = file
self.offset = offset
self.file.seek(self.offset)
hdr = struct.unpack("<I",self.file.read(4))[0]
self.uncompressed_length = hdr>>8
self.compression_type = hdr>>4 & 0xF
if self.compression_type != self.TYPE_LZ77:
raise ValueError("Unsupported compression method %d"%self.compression_type)
def uncompress(self):
dout = ""
self.file.seek(self.offset + 0x4)
while len(dout) < self.uncompressed_length:
flags = struct.unpack("<B",self.file.read(1))[0]
for i in range(8):
if flags & 0x80:
info = struct.unpack(">H",self.file.read(2))[0]
num = 3 + ((info>>12)&0xF)
disp = info & 0xFFF
ptr = len(dout) - (info & 0xFFF) - 1
for i in range(num):
dout += dout[ptr]
ptr+=1
if len(dout) >= self.uncompressed_length:
break
else:
dout += self.file.read(1)
flags <<= 1
if len(dout) >= self.uncompressed_length:
break
self.data = dout
return self.data
f = open(sys.argv[1])
hdr = f.read(4)
if hdr != "LZ77":
f.seek(0)
f.seek(0)
unc = WiiLZ77(f, f.tell())
du = unc.uncompress()
f2 = open(sys.argv[2],"w")
f2.write(du)
f2.close()
</source>
</source>