Source code for senseye_cameras.input.microphone

import time
import logging

import sounddevice as sd

from . input import Input

log = logging.getLogger(__name__)


class Microphone(Input):
    '''
    Reads in audio from a microphone.

    Args:
        id (str): device index
        config (dict): Configuration dictionary. Accepted keywords:
            channels (int): number of audio channels
            block_size (int): number of bytes to read in per iteration
            samplerate (int): audio sample rate
    '''

    def __init__(self, id=0, config=None):
        config = config or {}
        defaults = {
            'channels': 1,
            'blocksize': 1024,
            'samplerate': 44100,
        }
        Input.__init__(self, id=id, config=config, defaults=defaults)

    def configure(self):
        '''
        Supported configurations: samplerate, channels, blocksize
        '''
        device_info = sd.query_devices(self.id, 'input')
        if 'samplerate' not in self.config:
            self.config['samplerate'] = int(device_info['default_samplerate'])
        if 'channels' not in self.config:
            self.config['channels'] = device_info['max_input_channels']

    def open(self):
        '''Opens Audio stream'''
        if type(self.id) is str:
            device_list = sd.query_devices()
            self.id = [index for index, device_info in enumerate(device_list) if self.id in device_info['name']][0]

        self.configure()
        self.input = sd.InputStream(
            device=self.id,
            channels=self.config['channels'],
            samplerate=self.config['samplerate']
        )
        self.input.start()

    def read(self):
        '''Reads in audio blocks'''
        audio = None

        if self.input:
            audio, overflow = self.input.read(self.config['blocksize'])
            if overflow:
                audio = None
                log.warning('Audio block overflow')

        return audio, time.time()

    def close(self):
        if self.input:
            self.input.close()
        self.input = None