MAME Embedded Database

Optimized binary database for MAME arcade ROM identification, designed to be embedded in C on PC (Linux) or microcontroller (Raspberry Pi Pico 2).

Overview

This project transforms official MAME DAT files into a compact database (~12.5 MB) directly embedded in a C binary. The pipeline has 3 steps:

MAME DAT files
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 [Step 1] build_mame_database.py
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  SQLite database (mame_roms.db, ~40 MB)
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 [Step 2] generate_embedded_database.py
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  C source files + binary (src/ + include/)
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 [Step 3] gcc compilation
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  Executable with embedded database

Step 1: Build the SQLite database

The build_mame_database.py script downloads MAME DAT files from ProgettoSnaps and builds an optimized relational SQLite database.

pip install py7zr
python3 build_mame_database.py

Output: mame_roms.db

Full documentation: SQLITE_DATABASE.md

Step 2: Generate the embedded database

The generate_embedded_database.py script converts the SQLite database into a compact binary format with corresponding C files.

python3 generate_embedded_database.py

Output:

• mame_rom_database.bin — raw binary data
• include/mame_rom_database.h — C structures, macros and API
• src/mame_rom_database.c — C array containing the binary data

Full documentation: EMBEDDED_DATABASE.md

Step 3: Compilation and usage

PC / Linux

gcc -I include -I external/miniz -o example example.c src/mame_rom_database.c \
    external/miniz/miniz.c external/miniz/miniz_tinfl.c external/miniz/miniz_tdef.c

Raspberry Pi Pico 2

Add src/mame_rom_database.c and the miniz files to your CMakeLists.txt.

Example

The example.c file demonstrates how to:

1. Access the embedded database and verify the header
2. Search for a ROM by its SHA1 hash and size (binary search)
3. List all machines using that ROM
4. Navigate between machines (next / previous)

$ ./example
MAME Embedded Database v1
  ROMs: 157561 | Machines: 49537 | Manufacturers: 4233

Searching for SHA1: 48055822E0CEA228CDECF3D05AC24E50979B6F4D
ROM size: 2 MB (2097152 bytes)

ROM found!
This ROM is used by 8 machine(s):
  kaiserkn, kaiserknj, dankuga, gblchmp, ...

Project structure

mame_embedded_database/
├── build_mame_database.py        # Step 1: DAT -> SQLite
├── generate_embedded_database.py # Step 2: SQLite -> C binary
├── example.c                     # C API usage example
├── mame_roms.db                  # Generated SQLite database
├── mame_rom_database.bin         # Generated binary database
├── include/
│   └── mame_rom_database.h       # C header (structures, macros, API)
├── src/
│   └── mame_rom_database.c       # Embedded binary data as C array
├── external/
│   └── miniz/                    # zlib decompression library
├── SQLITE_DATABASE.md            # Step 1 documentation
├── EMBEDDED_DATABASE.md          # Step 2 documentation
└── README.md                     # This file

C API

The API is defined in include/mame_rom_database.h. Main functions:

Function	Description
mrdb_get_data()	Pointer to the embedded database
mrdb_get_header()	Access the header (magic, counters, offsets)
mrdb_find_rom_by_sha1()	Binary search for a ROM by size + SHA1
mrdb_get_machines_for_rom()	List all machines using a ROM
mrdb_get_machine_name()	Short machine name (e.g. "pacman")
mrdb_get_machine_description()	Full description (zlib decompression)
mrdb_get_machine_year()	Release year
mrdb_get_rom_name()	ROM filename

Statistics

Element	Value
ROMs	157,561
Machines	49,537
Manufacturers	4,233
Embedded database size	~12.5 MB