基于短时过零率的语音端点检测代码
时间: 2023-12-11 16:03:16 浏览: 49
以下是基于短时过零率的语音端点检测的 Python 代码示例:
```python
import numpy as np
import scipy.signal as signal
def short_time_energy(signal, window_size):
window = np.hamming(window_size)
energy = np.zeros(len(signal) - window_size)
for i in range(len(signal) - window_size):
energy[i] = np.sum(np.square(signal[i:i+window_size] * window))
return energy
def zero_crossing_rate(signal, window_size):
zero_crossings = np.where(np.diff(np.sign(signal)))[0]
zcr = np.zeros(len(signal) - window_size)
for i in range(len(signal) - window_size):
zcr[i] = len(np.intersect1d(zero_crossings, np.arange(i, i + window_size)))
return zcr
def endpoint_detection(signal, sample_rate, energy_threshold=0.2, zcr_threshold=0.5, window_size=400):
energy = short_time_energy(signal, window_size)
zcr = zero_crossing_rate(signal, window_size)
# Normalize energy and zcr
energy = (energy - np.min(energy)) / (np.max(energy) - np.min(energy))
zcr = (zcr - np.min(zcr)) / (np.max(zcr) - np.min(zcr))
# Compute endpoints based on energy and zcr thresholds
endpoints = np.where((energy > energy_threshold) & (zcr > zcr_threshold))[0]
# Add some padding to endpoints to avoid cutting off speech
padding = int(0.1 * sample_rate) # Add 100ms padding
endpoints = np.unique(np.concatenate((endpoints - padding, endpoints + padding)))
return endpoints
```
该代码包含三个函数:
1. `short_time_energy(signal, window_size)`: 计算输入信号的短时能量。
2. `zero_crossing_rate(signal, window_size)`: 计算输入信号的短时过零率。
3. `endpoint_detection(signal, sample_rate, energy_threshold, zcr_threshold, window_size)`: 基于短时能量和短时过零率的阈值检测语音端点。
使用方法如下:
```python
import soundfile as sf
# Load audio file
signal, sample_rate = sf.read("path/to/audio.wav")
# Detect endpoints
endpoints = endpoint_detection(signal, sample_rate, energy_threshold=0.2, zcr_threshold=0.5, window_size=400)
# Write audio segments to files
for i, endpoint in enumerate(endpoints):
if i == 0:
segment = signal[:endpoint]
elif i == len(endpoints) - 1:
segment = signal[endpoint:]
else:
segment = signal[endpoints[i-1]:endpoint]
sf.write(f"path/to/segment_{i+1}.wav", segment, sample_rate)
```
其中 `energy_threshold` 和 `zcr_threshold` 是能量和过零率的阈值,可以根据实际情况进行调整。`window_size` 是短时能量和短时过零率的窗口大小,一般取 20ms 到 40ms 左右。