使用USB Cam在Raspberry Pi中录制带有音频的视频

Question

如何使用内置麦克风的USB Cam在Raspberry Pi中录制带有音频的视频。 我能够分开做，但我需要一起做 我需要一个python代码。这是我用它来录制视频的代码：

def video_capture():
    global RS
    print 'try recording'
    global end_time
    fourcc = cv2.cv.CV_FOURCC(*'XVID')

    if end_time is None:
                    end_time = time.time()
    while True:
        while RS == 1:
            while time.time() - end_time >= 1:
                end_rec = time.time() + 20
                print 'writing video'
                t_start = time.time()
                while t_start < end_rec:
                    date_string = datetime.datetime.now().strftime('%Y%m%d%H%M%S')
                    out = cv2.VideoWriter(str(date_string)+'.avi',fourcc, 13, (640,480))
                    while (camera.isOpened()) & (time.time() < end_rec):
                        ret, frame3 = camera.read()
                        if ret==True:
                            out.write(frame3)
                    end_time = time.time()
                    break
                print 'The End'