将多通道PyAudio转换为NumPy数组

将多通道PyAudio转换为NumPy数组

它似乎是逐样本交错的，首先是左声道。通过左声道输入的信号和右声道的静音，我得到：

result = [0.2776, -0.0002,  0.2732, -0.0002,  0.2688, -0.0001,  0.2643, -0.0003,  0.2599, ...

因此，要将其分离为立体声流，可整形为2D数组：

result = np.fromstring(in_data, dtype=np.float32)result = np.reshape(result, (frames_per_buffer, 2))

现在访问左声道，使用

result[:, 0]

，对于右声道，使用

result[:, 1]

。

def depre(in_data, channels):    """    Convert a byte stream into a 2D numpy array with     shape (chunk_size, channels)    Samples are interleaved, so for a stereo stream with left channel     of [L0, L1, L2, ...] and right channel of [R0, R1, R2, ...], the output     is ordered as [L0, R0, L1, R1, ...]    """    # TODO: handle data type as parameter, convert between pyaudio/numpy types    result = np.fromstring(in_data, dtype=np.float32)    chunk_length = len(result) / channels    assert chunk_length == int(chunk_length)    result = np.reshape(result, (chunk_length, channels))    return resultdef enpre(signal):    """    Convert a 2D numpy array into a byte stream for PyAudio    Signal should be a numpy array with shape (chunk_size, channels)    """    interleaved = signal.flatten()    # TODO: handle data type as parameter, convert between pyaudio/numpy types    out_data = interleaved.astype(np.float32).tostring()    return out_data