final report

import queue import threading import time import pyaudio import numpy as np import math_work import options import sys import psk FORMAT = pyaudio.paInt16 frame_length = options.frame_length chunk = options.chunk search_freq = options.freq rate = options.rate sigil = [int(x) for x in options.sigil] frames_per_buffer = chunk * 10 in_length = 8000 # raw audio frames in_frames = queue.Queue(in_length) # the value of the fft at the frequency we care about points = queue.Queue(in_length) bits = queue.Queue(in_length / frame_length) wait_for_sample_timeout = 0.1 wait_for_frames_timeout = 0.1 wait_for_point_timeout = 0.1 wait_for_byte_timeout = 0.1 # yeeeep this is just hard coded bottom_threshold = 4000 def process_frames(): while True: try: frame = in_frames.get(False) fft = math_work.fft(frame) point = math_work.has_freq(fft, search_freq, rate, chunk) points.put(point) except queue.Empty: time.sleep(wait_for_frames_timeout) def process_points(): while True: cur_points = [] while len(cur_points) < frame_length: try: cur_points.append(points.get(False)) except queue.Empty: time.sleep(wait_for_point_timeout) while True: while np.average(cur_points) > bottom_threshold: try: cur_points.append(points.get(False)) cur_points = cur_points[1:] except queue.Empty: time.sleep(wait_for_point_timeout) next_point = None while next_point == None: try: next_point = points.get(False) except queue.Empty: time.sleep(wait_for_point_timeout) if next_point > bottom_threshold: bits.put(0) bits.put(0) cur_points = [cur_points[-1]] break print("") last_bits = [] while True: if len(cur_points) == frame_length: bit = int(math_work.get_bit(cur_points, frame_length) > bottom_threshold) cur_points = [] bits.put(bit) last_bits.append(bit) # if we've only seen low bits for a while assume the next message might not be on the same bit boundary if len(last_bits) > 3: if sum(last_bits) == 0: break last_bits = last_bits[1:] try: cur_points.append(points.get(False)) except queue.Empty: time.sleep(wait_for_point_timeout) def process_bits(): while True: cur_bits = [] # while the last two characters are not the sigil while len(cur_bits) < 2 or cur_bits[-len(sigil):len(cur_bits)] != sigil: try: cur_bits.append(bits.get(False)) except queue.Empty: time.sleep(wait_for_byte_timeout) sys.stdout.write(psk.decode(cur_bits[:-len(sigil)])) sys.stdout.flush() # start the queue processing threads processes = [process_frames, process_points, process_bits] threads = [] for process in processes: thread = threading.Thread(target=process) thread.daemon = True thread.start() def callback(in_data, frame_count, time_info, status): frames = list(math_work.chunks(math_work.unpack(in_data), chunk)) for frame in frames: if not in_frames.full(): in_frames.put(frame, False) return (in_data, pyaudio.paContinue) def start_analysing_stream(): p = pyaudio.PyAudio() stream = p.open(format=FORMAT, channels=options.channels, rate=options.rate, input=True, frames_per_buffer=frames_per_buffer, stream_callback=callback) stream.start_stream() while stream.is_active(): time.sleep(wait_for_sample_timeout) sys.stdout.write("Started listening at %sHz" % search_freq) sys.stdout.flush() start_analysing_stream()