在Raspberry pi模型上安装Google Assistant SDK时采样率无效b具有麦克风和扬声器的Sabrent usb

Question

我正在尝试安装谷歌助手sdk，使用覆盆子pi 3模型b和音频使用具有麦克风和扬声器（http://www.ebay.com/itm/Sabrent-External-Sound-Box-USB-SBCV/252367546463）的Sabrent usb。运行代码时出错。

python -m googlesamples.assistant

错误堆栈：

    Traceback (most recent call last):
  File "/usr/lib/python2.7/runpy.py", line 162, in _run_module_as_main
    "__main__", fname, loader, pkg_name)
  File "/usr/lib/python2.7/runpy.py", line 72, in _run_code
    exec code in run_globals
  File "/home/pi/env/lib/python2.7/site-packages/googlesamples/assistant/__main__.py", line 273, in <module>
    main()
  File "/home/pi/env/local/lib/python2.7/site-packages/click/core.py", line 722, in __call__
    return self.main(*args, **kwargs)
  File "/home/pi/env/local/lib/python2.7/site-packages/click/core.py", line 697, in main
    rv = self.invoke(ctx)
  File "/home/pi/env/local/lib/python2.7/site-packages/click/core.py", line 895, in invoke
    return ctx.invoke(self.callback, **ctx.params)
  File "/home/pi/env/local/lib/python2.7/site-packages/click/core.py", line 535, in invoke
    return callback(*args, **kwargs)
  File "/home/pi/env/lib/python2.7/site-packages/googlesamples/assistant/__main__.py", line 146, in main
    flush_size=audio_flush_size
  File "/home/pi/env/local/lib/python2.7/site-packages/googlesamples/assistant/audio_helpers/__init__.py", line 140, in __init__
    blocksize=int(block_size/2),  # blocksize is in number of frames.
  File "/home/pi/env/local/lib/python2.7/site-packages/sounddevice.py", line 1491, in __init__
    **_remove_self(locals()))
  File "/home/pi/env/local/lib/python2.7/site-packages/sounddevice.py", line 1017, in __init__
    'Error opening {0}'.format(self.__class__.__name__))
  File "/home/pi/env/local/lib/python2.7/site-packages/sounddevice.py", line 2671, in _check
    raise PortAudioError(msg)
sounddevice.PortAudioError: Error opening RawStream: Invalid sample rate

Answer 1

令人惊讶的是，这个错误恰恰意味着它所说的。您的声音设备不支持您尝试使用的采样率（可能在Google事物中可配置;您没有说明它或您尝试过的样本）。 USB设备通常只支持48kHz的DAT格式音频。 ALSA（Linux最常用的声音驱动程序集）并没有掩盖这一事实。可以要求它进行转换，例如使用asoundrc来设置默认插件。

Answer 2

我和你一样处于同样的问题但是，我可以通过编辑/home/pi/.asoundrc来解决这个问题，如下所示

    pcm.!default {
      type asym
      capture.pcm "usb_mic"
      playback.pcm "jack_speaker"
    }

    pcm.usb_mic {
      type plug
      slave {
        pcm "hw:1,0"
      }
    }

    pcm.jack_speaker {
      type plug
      slave {
        pcm "hw:0,0"
      }
    }

https://github.com/googlesamples/assistant-sdk-python/issues/4

Answer 3

我通过定义速率解决了这个问题，如下所示。在我阅读文档here之前，我在网上找到的任何其他内容都无法解决这个问题，我在黑暗中尝试了如何实现它。事实证明它对我有用。

pcm.!default {
  type asym
        playback.pcm {
        type plug
        slave.pcm "hw:0,0"
        rate 48000
   }
   capture.pcm {
     type plug
     slave.pcm "hw:1,0"
   }
}