tools/unpak.py

   1 #!/usr/bin/env python3
   2
   3 # requires Pillow and zstandard for Python
   4 # on msys, install Pillow with
   5 #   pacman -S mingw-w64-x86_64-python-pillow
   6 # zstd needs to be compiled, because the one in pip3 fails to do so:
   7 #   pacman -S mingw-w64-x86_64-python-setuptools mingw-w64-x86_64-zstd
   8 #   git clone https://github.com/indygreg/python-zstandard.git --recursive && cd python-zstandard
   9 #   python setup.py build_ext --external clean
  10 # run like this:
  11 #   ./unpak.py pakfile.pak outdir tools/default_crcmap.txt
  12 # any files not found in crcmap will go to the "nonmatching" folder
  13
  14 import os
  15 import sys
  16 import zstd
  17 import struct
  18 from PIL import Image
  19
  20 PAK_MAGIC = b'\x11\xde\x37\x10\x68\x75\xb6\xe8'
  21
  22 if len(sys.argv) < 3:
  23     print('usage: unpak <input.pak> <outdir> [<crcmap>]')
  24     sys.exit(1)
  25
  26 pakfname = sys.argv[1]
  27 outpath = sys.argv[2]
  28 mapfname = "crcmap.txt"
  29 if len(sys.argv) > 3:
  30     mapfname = sys.argv[3]
  31
  32 # load the CRC map
  33 crcmap = dict()
  34 try:
  35     with open(mapfname, 'r') as f:
  36         for line in f:
  37             line = line.strip()
  38             if line == '' or line[0] == '#':
  39                 continue
  40             tok = line.split(',')
  41             crcstr = tok[0].strip()
  42             if crcstr.startswith('0x'):
  43                 crc = int(crcstr[2:], 16)
  44             else:
  45                 crc = int(crcstr)
  46             path = os.path.join(outpath, tok[1].strip())
  47             if crc in crcmap:
  48                 crcmap[crc].append(path)
  49             else:
  50                 crcmap[crc] = [path]
  51 except OSError as e:
  52     print('could not open {0}: {1}'.format(mapfname, e))
  53     sys.exit(2)
  54 except ValueError as e:
  55     print('invalid integer in {0}: {1}'.format(mapfname, e))
  56     sys.exit(2)
  57
  58 unmatchdir = os.path.join(outpath, "nonmatching")
  59 if not os.path.exists(unmatchdir):
  60     os.makedirs(unmatchdir)
  61
  62 # read the PAK
  63 try:
  64     texlist = []
  65     with open(pakfname, "rb") as f:
  66         magic = f.read(len(PAK_MAGIC))
  67         if magic != PAK_MAGIC:
  68             print('invalid magic in PAK ' + pakfname)
  69             sys.exit(3)
  70         texcount = int.from_bytes(f.read(8), byteorder='little')
  71         print('reading {0} textures from {1}'.format(texcount, pakfname))
  72         for i in range(texcount):
  73             crc = int.from_bytes(f.read(4), byteorder='little')
  74             size = int.from_bytes(f.read(4), byteorder='little')
  75             offset = int.from_bytes(f.read(8), byteorder='little')
  76             width = int.from_bytes(f.read(8), byteorder='little')
  77             height = int.from_bytes(f.read(8), byteorder='little')
  78             texlist.append((crc, size, offset, width, height))
  79         for (crc, size, ofs, w, h) in texlist:
  80             f.seek(ofs)
  81             data = f.read(size)
  82             img = Image.frombytes('RGBA', (w, h), zstd.decompress(data))
  83             if crc in crcmap:
  84                 for path in crcmap[crc]:
  85                     [fpath, fname] = os.path.split(path)
  86                     if not os.path.exists(fpath):
  87                         os.makedirs(fpath)
  88                     img.save(path)
  89             else:
  90                 print('unknown crc: {0:08x}'.format(crc))
  91                 path = os.path.join(unmatchdir, "{0:08x}.png".format(crc))
  92                 img.save(path)
  93 except OSError as e:
  94     print('could not open {0}: {1}'.format(pakfname, e))
  95     sys.exit(3)