dtmf识别电话号码代码

以下是一个简单的DTMF识别电话号码的Python代码示例：

import numpy as np
from scipy.io import wavfile

# DTMF frequencies in Hz
tones = {
    '1': (697, 1209), '2': (697, 1336), '3': (697, 1477),
    '4': (770, 1209), '5': (770, 1336), '6': (770, 1477),
    '7': (852, 1209), '8': (852, 1336), '9': (852, 1477),
    '*': (941, 1209), '0': (941, 1336), '#': (941, 1477)
}

# Load the WAV file
rate, data = wavfile.read('dtmf_signal.wav')

# Compute the spectrogram
window_size = 0.01  # 10 ms
window_stride = 0.005  # 5 ms
nfft = int(window_size * rate)
hop_length = int(window_stride * rate)
spec = np.abs(np.array([np.fft.fft(data[i:i+nfft])
                        for i in range(0, len(data)-nfft, hop_length)]))

# Find the peak frequency in each spectrogram frame
freqs = np.array([np.argmax(spec[i, :nfft//2]) for i in range(spec.shape[0])])

# Find the DTMF tones by matching the frequency pairs
tones_detected = []
for i in range(len(freqs)-1):
    for tone, freq_pair in tones.items():
        if freq_pair == (freqs[i], freqs[i+1]):
            tones_detected.append(tone)
            break

# Print the detected phone number
print(''.join(tones_detected))

该代码假设已经有一个DTMF信号的WAV文件，并且使用短时傅里叶变换（STFT）计算音频的频谱图。然后，它在每个时段中找到频谱图中的峰值频率，然后匹配这些峰值对来识别DTMF音调。最后，它将检测到的DTMF音调连接起来，打印出电话号码。