Mega Man Legacy Collection ROM Extractor

mmlc_extract.py

#!/usr/bin/env python

# Program for extracting the NES roms of each game in the Mega Man Legacy
# Collection for PC

# iNES Headers for Mega Man 1-6
HEADERS = [b'\x4E\x45\x53\x1A\x08\x00\x21\x00\x00\x00\x00\x00\x00\x00\x00\x00',
           b'\x4E\x45\x53\x1A\x10\x00\x10\x00\x00\x00\x00\x00\x00\x00\x00\x00',
           b'\x4E\x45\x53\x1A\x10\x10\x40\x00\x00\x00\x00\x00\x00\x00\x00\x00',
           b'\x4E\x45\x53\x1A\x20\x00\x40\x00\x00\x00\x00\x00\x00\x00\x00\x00',
           b'\x4E\x45\x53\x1A\x10\x20\x40\x00\x00\x00\x00\x00\x00\x00\x00\x00',
           b'\x4E\x45\x53\x1A\x20\x00\x40\x00\x00\x00\x00\x00\x00\x00\x00\x00']

# Offsets for each game's ROM in the .exe file
# v1.1.0.78         OFFSET     SIZE             OFFSET      SIZE
OFFSETS = [{'PRG': [0x191F468, 0x20000], 'CHA': None},
           {'PRG': [0x16FF468, 0x40000], 'CHA': None},
           {'PRG': [0x175F468, 0x40000], 'CHA': [0x173F468, 0x20000]},
           {'PRG': [0x179F468, 0x80000], 'CHA': None},
           {'PRG': [0x181F468, 0x40000], 'CHA': [0x185F468, 0x40000]},
           {'PRG': [0x189F468, 0x80000], 'CHA': None}]

if __name__ == '__main__':
    # Read in entire .exe file
    f = open("Proteus.exe", "rb")
    try:
        exe = f.read()
    finally:
        f.close()

    for i, game in enumerate(HEADERS):
        for section in ['PRG', 'CHA']:
            if OFFSETS[i][section]:
                start = OFFSETS[i][section][0]
                size = OFFSETS[i][section][1]
                end = start + size
                game += exe[start:end]
        out = open("Mega Man " + str(i+1) + ".nes", "wb")
        try:
            out.write(game)
        finally:
            out.close()

TODO

• Search for offsets rather than use fixed ones
• CLI Interface
• Error handling
• Make it more Pythonic I guess

@anpage:
Your 2017 script version no longer works with the latest Steam EXE. I created a fork to update the offsets and also added the extraction of the Japanese ROMs. There seems to be no way to do a pull request for gists, so here's my fork that you can copy from into your repository:
https://gist.github.com/VideogameScrapbook/e1dc851234b0bdba97b0c73cf9f52aed