guvcview gives error: invalid pixel format on Ubuntu 24.04

[JohannesBuchner]

After sudo weffe -a and weffe, I see the camera light on and ffmpeg is running.

The first line of weffe output is, however: ioctl(VIDIOC_QBUF): Bad file descriptor

Next, I wanted to see what the video output looks like.

running guvcview allows one to select the camera source "Weffe" from its dropdown menu.

But then it gives the error "invalid pixel format".

Here is the terminal output:

V4L2_CORE: Unable to find parent usb device.GUVCVIEW: version 2.0.8
V4L2_CORE: (UVCIOC_CTRL_MAP) Error: No such file or directory
V4L2_CORE: (UVCIOC_CTRL_MAP) Error: No such file or directory
V4L2_CORE: (UVCIOC_CTRL_MAP) Error: No such file or directory
V4L2_CORE: (UVCIOC_CTRL_MAP) Error: No such file or directory
V4L2_CORE: (UVCIOC_CTRL_MAP) Error: No such file or directory
V4L2_CORE: (UVCIOC_CTRL_MAP) Error: No such file or directory
V4L2_CORE: (UVCIOC_CTRL_MAP) Error: No such file or directory
V4L2_CORE: (UVCIOC_CTRL_MAP) Error: No such file or directory
V4L2_CORE: (UVCIOC_CTRL_MAP) Error: No such file or directory
libv4l2: error setting pixformat: Device or resource busy
V4L2_CORE: (VIDIOC_S_FORMAT) Unable to set format: Device or resource busy
GUCVIEW: could not set the defined stream format
GUCVIEW: trying first listed stream format
libv4l2: error setting pixformat: Device or resource busy
V4L2_CORE: (VIDIOC_S_FORMAT) Unable to set format: Device or resource busy
GUCVIEW: also could not set the first listed stream format
GUVCVIEW: Video capture failed
GUVCVIEW (1): Guvcview error
	 could not start a video stream in the device
control[0]:(unknown - 0x6) 0x980001 'User Controls'
control[12]:(unknown - 0x6) 0x9a0001 'Camera Controls'
GUVCVIEW (1): Guvcview error
	 invalid pixel format
V4L2_CORE: Unable to find parent usb device.GUVCVIEW: version 2.0.8
GUVCVIEW: couldn't open /home/user/.config/guvcview2/video7 for read: No such file or directory
V4L2_CORE: (UVCIOC_CTRL_MAP) Error: Inappropriate ioctl for device
V4L2_CORE: (UVCIOC_CTRL_MAP) Error: Inappropriate ioctl for device
V4L2_CORE: (UVCIOC_CTRL_MAP) Error: Inappropriate ioctl for device
V4L2_CORE: (UVCIOC_CTRL_MAP) Error: Inappropriate ioctl for device
V4L2_CORE: (UVCIOC_CTRL_MAP) Error: Inappropriate ioctl for device
V4L2_CORE: (UVCIOC_CTRL_MAP) Error: Inappropriate ioctl for device
V4L2_CORE: (UVCIOC_CTRL_MAP) Error: Inappropriate ioctl for device
V4L2_CORE: (UVCIOC_CTRL_MAP) Error: Inappropriate ioctl for device
V4L2_CORE: (UVCIOC_CTRL_MAP) Error: Inappropriate ioctl for device
ALSA lib pcm.c:2721:(snd_pcm_open_noupdate) Unknown PCM cards.pcm.front
ALSA lib pcm.c:2721:(snd_pcm_open_noupdate) Unknown PCM cards.pcm.rear
ALSA lib pcm.c:2721:(snd_pcm_open_noupdate) Unknown PCM cards.pcm.center_lfe
ALSA lib pcm.c:2721:(snd_pcm_open_noupdate) Unknown PCM cards.pcm.side
ALSA lib pcm.c:2721:(snd_pcm_open_noupdate) Unknown PCM cards.pcm.surround21
ALSA lib pcm.c:2721:(snd_pcm_open_noupdate) Unknown PCM cards.pcm.surround21
ALSA lib pcm.c:2721:(snd_pcm_open_noupdate) Unknown PCM cards.pcm.surround40
ALSA lib pcm.c:2721:(snd_pcm_open_noupdate) Unknown PCM cards.pcm.surround41
ALSA lib pcm.c:2721:(snd_pcm_open_noupdate) Unknown PCM cards.pcm.surround50
ALSA lib pcm.c:2721:(snd_pcm_open_noupdate) Unknown PCM cards.pcm.surround51
ALSA lib pcm.c:2721:(snd_pcm_open_noupdate) Unknown PCM cards.pcm.surround71
ALSA lib pcm.c:2721:(snd_pcm_open_noupdate) Unknown PCM cards.pcm.iec958
ALSA lib pcm.c:2721:(snd_pcm_open_noupdate) Unknown PCM cards.pcm.iec958
ALSA lib pcm.c:2721:(snd_pcm_open_noupdate) Unknown PCM cards.pcm.iec958
ALSA lib pcm.c:2721:(snd_pcm_open_noupdate) Unknown PCM cards.pcm.hdmi
ALSA lib pcm.c:2721:(snd_pcm_open_noupdate) Unknown PCM cards.pcm.hdmi
ALSA lib pcm.c:2721:(snd_pcm_open_noupdate) Unknown PCM cards.pcm.modem
ALSA lib pcm.c:2721:(snd_pcm_open_noupdate) Unknown PCM cards.pcm.modem
ALSA lib pcm.c:2721:(snd_pcm_open_noupdate) Unknown PCM cards.pcm.phoneline
ALSA lib pcm.c:2721:(snd_pcm_open_noupdate) Unknown PCM cards.pcm.phoneline
ALSA lib pcm_dmix.c:1000:(snd_pcm_dmix_open) unable to open slave
Cannot connect to server socket err = No such file or directory
Cannot connect to server request channel
jack server is not running or cannot be started
JackShmReadWritePtr::~JackShmReadWritePtr - Init not done for -1, skipping unlock
JackShmReadWritePtr::~JackShmReadWritePtr - Init not done for -1, skipping unlock
V4L2_CORE: (VIDIOC_QUERYBUF) Unable to query buffer[3]: Invalid argument
         try with read method instead
V4L2_CORE: (VIDIOC_QBUFS) Unable to query buffers: Invalid argument
GUCVIEW: could not set the defined stream format
GUCVIEW: trying first listed stream format
V4L2_CORE: (VIDIOC_QUERYBUF) Unable to query buffer[3]: Invalid argument
         try with read method instead
V4L2_CORE: (VIDIOC_QBUFS) Unable to query buffers: Invalid argument
GUCVIEW: also could not set the first listed stream format
GUVCVIEW: Video capture failed
GUVCVIEW (1): Guvcview error
	 could not start a video stream in the device
control[0]:(unknown - 0x6) 0x980001 'User Controls'
V4L2_CORE: V4L2_CAP_TIMEPERFRAME not supported
GUVCVIEW: invalid pixel format
V4L2_CORE: [get resolution index] format index (-1) is not valid [0 - 5]
GUVCVIEW (1): Guvcview error
	 invalid resolution index
GUVCVIEW: invalid resolution index
Segmentation fault (core dumped)