Reads an audio signal from file.

    Supported formats : wav

    :param filename: filename of the audiofile to load
    :type filename: str
    :returns: int, numpy.ndarray -- samplerate, array containing the audio signal

def audioread(filename):
    """Reads an audio signal from file.

    Supported formats : wav

    :param filename: filename of the audiofile to load
    :type filename: str
    :returns: int, numpy.ndarray -- samplerate, array containing the audio signal
    """
    try:
        if '.wav' in filename.lower():
            fs, signal = wv.read(filename)
        elif '.call' in filename.lower():
            with open(filename, 'rb') as f:
                signal = np.fromfile(f, dtype=np.int16)
            fs = 333333
        else:
            raise IOError("Unsupported audio format for file: {}".format(filename))
    except:
        print u"Problem reading wav file"
        raise
    signal = signal.astype(float)
    return fs, signal