[Errno -9996]

[hugoneedshelp]

Hey guys! So I'm a noob at this and I need your help,

so when I do the command:
sudo python3 visualization.py scroll
This pops up, can someone help me fix this?

ALSA lib pcm.c:2660:(snd_pcm_open_noupdate) Unknown PCM cards.pcm.front
ALSA lib pcm.c:2660:(snd_pcm_open_noupdate) Unknown PCM cards.pcm.rear
ALSA lib pcm.c:2660:(snd_pcm_open_noupdate) Unknown PCM cards.pcm.center_lfe
ALSA lib pcm.c:2660:(snd_pcm_open_noupdate) Unknown PCM cards.pcm.side
ALSA lib pcm.c:2660:(snd_pcm_open_noupdate) Unknown PCM cards.pcm.surround21
ALSA lib pcm.c:2660:(snd_pcm_open_noupdate) Unknown PCM cards.pcm.surround21
ALSA lib pcm.c:2660:(snd_pcm_open_noupdate) Unknown PCM cards.pcm.surround40
ALSA lib pcm.c:2660:(snd_pcm_open_noupdate) Unknown PCM cards.pcm.surround41
ALSA lib pcm.c:2660:(snd_pcm_open_noupdate) Unknown PCM cards.pcm.surround50
ALSA lib pcm.c:2660:(snd_pcm_open_noupdate) Unknown PCM cards.pcm.surround51
ALSA lib pcm.c:2660:(snd_pcm_open_noupdate) Unknown PCM cards.pcm.surround71
ALSA lib pcm.c:2660:(snd_pcm_open_noupdate) Unknown PCM cards.pcm.iec958
ALSA lib pcm.c:2660:(snd_pcm_open_noupdate) Unknown PCM cards.pcm.iec958
ALSA lib pcm.c:2660:(snd_pcm_open_noupdate) Unknown PCM cards.pcm.iec958
ALSA lib confmisc.c:1281:(snd_func_refer) Unable to find definition 'cards.bcm2835_headpho.pcm.hdmi.0:CARD=0,AES0=4,AES1=130,AES2=0,AES3=2'
ALSA lib conf.c:4745:(_snd_config_evaluate) function snd_func_refer returned error: No such file or directory
ALSA lib conf.c:5233:(snd_config_expand) Evaluate error: No such file or directory
ALSA lib pcm.c:2660:(snd_pcm_open_noupdate) Unknown PCM hdmi
ALSA lib confmisc.c:1281:(snd_func_refer) Unable to find definition 'cards.bcm2835_headpho.pcm.hdmi.0:CARD=0,AES0=4,AES1=130,AES2=0,AES3=2'
ALSA lib conf.c:4745:(_snd_config_evaluate) function snd_func_refer returned error: No such file or directory
ALSA lib conf.c:5233:(snd_config_expand) Evaluate error: No such file or directory
ALSA lib pcm.c:2660:(snd_pcm_open_noupdate) Unknown PCM hdmi
ALSA lib pcm.c:2660:(snd_pcm_open_noupdate) Unknown PCM cards.pcm.modem
ALSA lib pcm.c:2660:(snd_pcm_open_noupdate) Unknown PCM cards.pcm.modem
ALSA lib pcm.c:2660:(snd_pcm_open_noupdate) Unknown PCM cards.pcm.phoneline
ALSA lib pcm.c:2660:(snd_pcm_open_noupdate) Unknown PCM cards.pcm.phoneline
connect(2) call to /dev/shm/jack-0/default/jack_0 failed (err=No such file or directory)
attempt to connect to server failed
connect(2) call to /dev/shm/jack-0/default/jack_0 failed (err=No such file or directory)
attempt to connect to server failed
ALSA lib pcm_oss.c:377:(_snd_pcm_oss_open) Unknown field port
ALSA lib pcm_oss.c:377:(_snd_pcm_oss_open) Unknown field port
ALSA lib pulse.c:242:(pulse_connect) PulseAudio: Unable to connect: Connection refused

ALSA lib pulse.c:242:(pulse_connect) PulseAudio: Unable to connect: Connection refused

ALSA lib pcm_a52.c:823:(_snd_pcm_a52_open) a52 is only for playback
ALSA lib conf.c:5200:(snd_config_expand) Unknown parameters {AES0 0x6 AES1 0x82 AES2 0x0 AES3 0x2 CARD 0}
ALSA lib pcm.c:2660:(snd_pcm_open_noupdate) Unknown PCM iec958:{AES0 0x6 AES1 0x82 AES2 0x0 AES3 0x2 CARD 0}
ALSA lib pcm_usb_stream.c:486:(_snd_pcm_usb_stream_open) Invalid type for card
ALSA lib pcm_usb_stream.c:486:(_snd_pcm_usb_stream_open) Invalid type for card
ALSA lib pcm_hw.c:1829:(_snd_pcm_hw_open) Invalid value for card
ALSA lib pcm_hw.c:1829:(_snd_pcm_hw_open) Invalid value for card
ALSA lib pcm_hw.c:1829:(_snd_pcm_hw_open) Invalid value for card
ALSA lib pcm_hw.c:1829:(_snd_pcm_hw_open) Invalid value for card
ALSA lib pcm_dmix.c:1009:(snd_pcm_dmix_open) The dmix plugin supports only playback stream
ALSA lib pcm_direct.c:1846:(_snd_pcm_direct_get_slave_ipc_offset) Invalid value for card
ALSA lib pcm_direct.c:1846:(_snd_pcm_direct_get_slave_ipc_offset) Invalid value for card
ALSA lib pcm_dmix.c:1009:(snd_pcm_dmix_open) The dmix plugin supports only playback stream
ALSA lib pcm_direct.c:1846:(_snd_pcm_direct_get_slave_ipc_offset) Invalid value for card
ALSA lib pcm_hw.c:1829:(_snd_pcm_hw_open) Invalid value for card
ALSA lib pcm_direct.c:1846:(_snd_pcm_direct_get_slave_ipc_offset) Invalid value for card
connect(2) call to /dev/shm/jack-0/default/jack_0 failed (err=No such file or directory)
attempt to connect to server failed
Traceback (most recent call last):
File "/home/pi/dancyPi-audio-reactive-led/python/visualization.py", line 420, in
microphone.start_stream(microphone_update)
File "/home/pi/dancyPi-audio-reactive-led/python/microphone.py", line 10, in start_stream
stream = p.open(format=pyaudio.paInt16,
File "/usr/lib/python3/dist-packages/pyaudio.py", line 750, in open
stream = Stream(self, *args, **kwargs)
File "/usr/lib/python3/dist-packages/pyaudio.py", line 441, in init
self._stream = pa.open(**arguments)
OSError: [Errno -9996] Invalid input device (no default output device)

[kyle-hunady]

Haha, also having a difficult time with finding the default device. Using mic mode on RPi 3B.

Technically I don't have a USB mic plugged in (awaiting shipment), so that could be the issue. However, I do have an AUX mic plugged into the headphone jack. I did a lot of googling. Making sure a default device is set isn't easy for a beginner like myself--something to do with faulty install for dependencies of pyaudio.

However, pyaudio only throws this error because you did not specify a specific device to use, so it checks for a default. The error comes from this code:

stream = p.open(format=pyaudio.paInt16,
                    channels=1,
                    rate=config.MIC_RATE,
                    input=True,
                    frames_per_buffer=frames_per_buffer)

So here's my workaround: there's another parameter that allows you to explicitly choose your device to bypass needing a default...

stream = p.open(format=pyaudio.paInt16,
                    channels=1,
                    rate=config.MIC_RATE,
                    input=True,
                    frames_per_buffer=frames_per_buffer,
                    input_device_index=0) # choosing device 0

How do you know the index of your device? Pyaudio can tell you! Here's a little snippet I put it into microphone.py:

# some statements above...
# in microphone.py
def start_stream(callback):
    p = pyaudio.PyAudio()

    # list devices (code from https://stackoverflow.com/questions/36894315/how-to-select-a-specific-input-device-with-pyaudio)
    info = p.get_host_api_info_by_index(0)
    numdevices = info.get('deviceCount')
    print("Device count: ", numdevices) # look for this in console output
    # and the rest ...

I ran sudo python3 visualization.py scroll again, and scanned through the errors to find the device list. I only had one from my console output, here's a snippet:

Device count:  1
Input Device id  0  -  bcm2835 Headphones: - (hw:0,0)

Here's my new microphone.py that lists all devices and hardcodes the index for headphones:

# microphone.py
import time
import numpy as np
import pyaudio
import config


def start_stream(callback):
    print("In start_stream")
    p = pyaudio.PyAudio()

    print("Initialized pyaudio")
    # list devices (https://stackoverflow.com/questions/36894315/how-to-select-a-specific-input-device-with-pyaudio)
    info = p.get_host_api_info_by_index(0)
    numdevices = info.get('deviceCount')
    print("Device count: ", numdevices)

    for i in range(0, numdevices):
        # if (p.get_device_info_by_host_api_device_index(0, i).get('maxInputChannels')) > 0:
        print("Input Device id ", i, " - ", p.get_device_info_by_host_api_device_index(0, i).get('name'))
    # end list devices
    
    # default_info = p.get_default_input_device_info()
    # print(default_info.get('name'))

    frames_per_buffer = int(config.MIC_RATE / config.FPS)
    stream = p.open(format=pyaudio.paInt16,
                    channels=1,
                    rate=config.MIC_RATE,
                    input=True,
                    frames_per_buffer=frames_per_buffer,
                    input_device_index=0)
    overflows = 0
    prev_ovf_time = time.time()
    while True:
        try:
            y = np.fromstring(stream.read(frames_per_buffer, exception_on_overflow=False), dtype=np.int16)
            y = y.astype(np.float32)
            stream.read(stream.get_read_available(), exception_on_overflow=False)
            callback(y)
        except IOError:
            overflows += 1
            if time.time() > prev_ovf_time + 1:
                prev_ovf_time = time.time()
                print('Audio buffer has overflowed {} times'.format(overflows))
    stream.stop_stream()
    stream.close()
    p.terminate()

I got past the default device error, but now it claims it has an invalid number of channels. I'll have to see what that means when I have time tomorrow.

[kyle-hunady]

Ah, well, the internet tells me that the headphone jack on RPi is actually strictly output (no mic input). So I was doomed to fail. Maybe that's causing the invalid channel number issue.

It seems USB-cams are a necessity. I'll be getting one soon.

[naztronaut]

Ah, well, the internet tells me that the headphone jack on RPi is actually strictly output (no mic input).

Sadly.

You don't need a camera, just a USB mic should do.

@hugoneedshelp if you still need help, try these commands and let me know what you see:

• cat /proc/asound/cards
• cat /etc/modules
• arecord -l
• aplay -l

You can also run the script that Kyle posted above.

Apologies to anyone who are still waiting for responses from me. I've shifted focus so so I haven't had a lot of time to work on my Raspberry Pi projects.