sndcard.py 文件源码

def _data_format(self, x):
        """The data types in numpy needs to be mapped to the equivalent type in
        portaudio. This is an issue for 24 bit audio files since there isn't a
        24 bit data type in numpy. This is currently not implemented. There are
        some options on how to do this. We could for example use a 32 bit int and
        store the 24 bits either so that bits 1 to 8 is set to zeroes or so that
        bits 25 to 32 is set to zeros.
        """
        retval = None

        if x.samples.dtype == np.dtype(np.float32):
            self._logger.debug("pyaudio.paFloat32")
            retval = pyaudio.paFloat32
        elif x.samples.dtype == np.dtype(np.int16):
            self._logger.debug("pyaudio.paInt16")
            retval = pyaudio.paInt16
        elif x.samples.dtype == np.dtype(np.int32):
            self._logger.debug("pyaudio.paInt32")
            retval = pyaudio.paInt32
        else:
            raise NotImplementedError("Data type not understood: %s" %x.samples.dtype)

        return retval