diff options
Diffstat (limited to 'utils.py')
| -rw-r--r-- | utils.py | 59 |
1 files changed, 46 insertions, 13 deletions
@@ -4,6 +4,38 @@ import numpy as np import pyaudio import threading +from scipy.fftpack import fft + + +def wave_to_bits(wave, starting_freq, freq_range, bytes_per_transmit, chunk=4096, rate=44100): + spectrum = fft(wave) + spectrum = np.abs(spectrum) + spectrum = spectrum / (np.linalg.norm(spectrum) + 1e-16) + + # FIXME: update to self values, given if ur a sender or receiver + starting_freq = starting_freq + end_freq = starting_freq + freq_range + freq_to_index_ratio = (chunk - 1) / rate + + # only accept the scaled spectrum from our starting range to 20000 Hz + starting_range_index = int(starting_freq * freq_to_index_ratio) + ending_range_index = int(end_freq * freq_to_index_ratio) + restricted_spectrum = spectrum[starting_range_index:ending_range_index + 1] + + # get the n indices of the max peaks of amplitude greater than .125, within our confined spectrum + indices = np.argwhere(restricted_spectrum > .125) + + freqs = [int((indices[i] + starting_range_index) / freq_to_index_ratio) for i in range(len(indices))] + + # convert the frequencies to bits + data = frequencies_to_bits(freqs, calculate_send_frequencies(starting_freq, freq_range, bytes_per_transmit)) + + # TODO: remove + byte = data[:8] + if data[-1] == '1': + receive_string(byte) + + return data def calculate_send_frequencies(start_freq, freq_range, bytes_per_transmit): @@ -15,49 +47,50 @@ def calculate_send_frequencies(start_freq, freq_range, bytes_per_transmit): f = int(start_freq + (i + 1) * freq_interval) freq_list.append(f) - print(freq_list) - return freq_list -def frequencies_to_bytes(frequencies, expected_freqs): +def frequencies_to_bits(frequencies, expected_freqs): # get the interval between frequencies, so we can clamp the range around them freq_interval = expected_freqs[1] - expected_freqs[0] plus_minus = freq_interval // 2 - byte_list = ['0'] * len(expected_freqs) + bit_list = ['0'] * len(expected_freqs) for freq in frequencies: for i in range(len(expected_freqs)): # clamp the range around the frequency to the frequency if expected_freqs[i] - plus_minus <= freq < expected_freqs[i] + plus_minus: - byte_list[i] = '1' + bit_list[i] = '1' - return byte_list + return bit_list -def play_data(data, start_freq, freq_step, bytes_per_transmit, p): + +def play_data(data, start_freq, freq_step, bytes_per_transmit, stream): freq_list = calculate_send_frequencies(start_freq, freq_step, bytes_per_transmit) + send_duration = 1.0 + + flip_flag = 0 # TODO: make this global between plays for byte in data: + byte = byte + str(flip_flag) + '1' print(byte) samples = None for i, bit in enumerate(byte): if bit == '1': print(freq_list[i]) - s = .125 * np.sin(2 * np.pi * np.arange(44100 * 10.0) * freq_list[i] / 44100) + s = .125 * np.sin(2 * np.pi * np.arange(44100 * send_duration) * freq_list[i] / 44100) if samples is None: samples = s else: samples = np.add(samples, s) if samples is not None: - print(samples) - stream = p.open(format=pyaudio.paFloat32, channels=1, rate=44100, output=True) stream.write(samples.astype(np.float32).tobytes()) - stream.stop_stream() - stream.close() + flip_flag = (flip_flag + 1) % 2 + def receive_string(binary): binary_string = ''.join(binary) try: print(chr(int(binary_string, 2))) except ValueError: - print("Error: Invalid binary data")
\ No newline at end of file + print("Error: Invalid binary data") |