From 21fd7b8e92234b80cba34a9f6d8924e81a7ed313 Mon Sep 17 00:00:00 2001 From: Rangi Date: Sun, 13 Sep 2020 21:07:34 -0400 Subject: Start decompressing data (to do: implement a compressor) --- tools/dump_decompress.py | 33 +++++++++++++++++++++++++++++++++ 1 file changed, 33 insertions(+) create mode 100644 tools/dump_decompress.py (limited to 'tools/dump_decompress.py') diff --git a/tools/dump_decompress.py b/tools/dump_decompress.py new file mode 100644 index 0000000..2776c2b --- /dev/null +++ b/tools/dump_decompress.py @@ -0,0 +1,33 @@ +#!/usr/bin/env python3 + +# Usage: ./dump_decompress.py 75:7d35 00b6 >compressed.bin 2>decompressed.bin + +from sys import argv, stdout, stderr + +file = open("DMGAKVJ0.1", "rb").read() + +bank_addr = argv[1].split(':') +bank = int(bank_addr[0], 16) +addr = int(bank_addr[1], 16) +length = int(argv[2], 16) +offset = bank * 0x4000 + addr - (0x4000 if bank else 0) + +output = [] +i = offset +v = 0x00 +for _1 in range(length): + byte = file[i] + i += 1 + if byte < 0x80: + for _2 in range(byte + 1): + v ^= file[i] + output.append(v) + i += 1 + else: + for _2 in range(byte - 0x7e): + v ^= file[i] + output.append(v) + i += 1 + +stdout.buffer.write(bytes(file[offset:i])) # compressed +stderr.buffer.write(bytes(output)) # decompressed -- cgit v1.2.3