noise.py

import hashlib
import math
import re
import struct
import wave

def remap_value(value, min_x, max_x, min_y, max_y):
    normalized = (value - min_x) / float(max_x)
    return min_y + (normalized * (max_y - min_y))

sample_rate = 44100

def generate_line_tone(noise, line, amplitude):
    m = hashlib.md5(line)

    tones = []
    tone_map = re.findall(".{4}", m.hexdigest())

    for tone in tone_map:
        tone = float(int("0x" + tone, 16))
        tone = remap_value(tone, 0x0000, 0xffff, 220, 440)
        tones.append(tone)

    samples = []
    sample_amount = int(sample_rate / 10.0)
    for i in range(sample_amount):
        sample = 1
        for tone in tones:
            sample *= math.sin(i * (sample_rate / tone))

        samples.append(int(sample * amplitude))

    noise.writeframes("".join(struct.pack("h", sample) for sample in samples))

max_amplitude = math.pow(2, 16) / 2.0
noise = wave.open("noise.wav", "wb")

noise.setnchannels(1)            # mono
noise.setsampwidth(2)            # 16 bit
noise.setframerate(sample_rate)  # CD quality

with open("code.txt", "r") as code_file:
    longest_line = 0
    for code_line in code_file:
        longest_line = max(longest_line, len(code_line))

    longest_line = float(longest_line)
    code_file.seek(0)

    for code_line in code_file:
        line_amplitude = max_amplitude * (len(code_line) / longest_line)
        generate_line_tone(noise, code_line, line_amplitude)

noise.close()