soco_alarm_sound_dumper.py

#!/usr/bin/env python3

# Usage: soco_alarm_sound_dumper.py <alarm_spi_flash_dump_file>
# 
# This script reads the sounds from specified Super Soco alarm module
# memory dump and exports them as playable Wave files.
#
# There seems to be a "table of contents" (ToC) at the beginning of
# SPI flash that defines the location and length of each sound.
# Each ToC entry is 8 bytes long, where 4 bytes are the sound offset and
# and next 4 bytes are denoting the length. After the last ToC entry
# there is a value which I couldn't figure out, that's what causes the
# error about current sound offset being greater that last sound's offset.
#
# Sounds I have found in memory dumps from two alarm modules:
# (listed in no particular order)
#   - Lock/unlock/startup sound made out of iPhone "Popcorn" alarm tone
#   - Lock/unlock/startup featuring the infamous piano jingle startup that
#     pissed me so much I started working on this script
#   - Lock/unlock/startup bleeps which I presumed to be some old stuff
#     that was supposed to be played on a piezoelectric speaker, but then
#     I met someone with a '19 TC Max which used these
#   - Error tone which can be heard when you keep pressing Start button
#     repeatedly
#   - Rather long alarm siren that takes a lot of memory space
#   - Short alarm siren
#   - Shutdown sound
# 
# Sound format: Raw PCM frames, 11025Hz framerate, mono.
# On two different alarm modules these sounds were stored on 
# a BoyaMicro 25D16ASTIG SPI flash chip that I was able to read using CH341
# and flashrom utility on Linux.
#
# I'm sharing this because I don't have time nor will to play with this anymore.

import sys
import struct
import wave

sounds = []

with open(sys.argv[1], 'rb') as f:
    for _ in range(16):
        chunk = f.read(8)
        if len(chunk) < 8:
            break
        offset, length = struct.unpack('>ii', chunk)
        sounds.append((offset, length))

    for i, sound in enumerate(sounds):
        f.seek(sound[0])
        if i+1 < len(sounds):
            length = sounds[i+1][0] - sound[0]
            if length < 0:
                print(f"Error: sound{i} offset is greater than sound{i+1} offset")
                continue 
            data = f.read(length)
        else:
            data = f.read()

        with open(f'sound{i}.pcm', 'wb') as raw_file:
            raw_file.write(data)

        with wave.open(f'sound{i}.wav', 'wb') as sound_file:
            sound_file.setnchannels(1)
            sound_file.setsampwidth(4)
            sound_file.setframerate(11025.0)
            sound_file.writeframesraw(data)

for i, sound in enumerate(sounds):
    print(f'[sound{i}] Offset: {sound[0]:x}, Length: {sound[1]:x}')