Error fetching frame

[bobyang9]

This feels like an installation problem, hence, "Discussion", but if it turns out to be an issue, I'll move this to the "Issues" side.

I am running examples/webcam_filter.py and I am getting the error message below:

Webcam capture started (1280x720 @ 30.0fps)
Virtual cam started: OBS Virtual Camera (1280x720 @ 20fps)
Traceback (most recent call last):
  File "sample.py", line 48, in <module>
    raise RuntimeError('Error fetching frame')
RuntimeError: Error fetching frame

Do you have any advice on this error?

Information:
I have OBS installed on Mac and followed the setup steps {install obs, start obs, click start virtual camera, click end virtual camera, close obs}.
Mac 11.3.1
Python 3.7.11
I have the other dependencies argparse and cv2
I had zoom open and taking the OBS webcam as video during the time
I am running the script examples/webcam_filter.py without any changes so you can reference the one in the repo
I saw the readme and the part regarding obs ("so it is not possible to send frames from Python, capture the camera in OBS, mix it with other content, and output it again as virtual camera.") and don't know if webcam_filter.py matches that description

[letmaik]

The line that throws the error is from OpenCV trying to read a frame from your webcam. This is independent of pyvirtualcam. Check if you have multiple video devices, maybe you just have to use a different one with the --camera 0 CLI argument. Try 1, or 2.

[douglassllc]

I am on Bullseye 32 bit. Pi Camera v3.

/boot/config.txt

dtoverlay=imx708
gpu_mem=256
arm_64bit=0

I installed all required python dependencies using apt install, not pip install

I am receiving this same error.

python webcam_filter.py --camera 0
[ WARN:0] global ../modules/videoio/src/cap_gstreamer.cpp (1824) handleMessage OpenCV | GStreamer warning: Embedded video playback halted; module v4l2src0 reported: Failed to allocate required memory.
[ WARN:0] global ../modules/videoio/src/cap_gstreamer.cpp (914) open OpenCV | GStreamer warning: unable to start pipeline
[ WARN:0] global ../modules/videoio/src/cap_gstreamer.cpp (501) isPipelinePlaying OpenCV | GStreamer warning: GStreamer: pipeline have not been created
[ WARN:0] global ../modules/videoio/src/cap_v4l.cpp (1914) getProperty VIDEOIO(V4L2:/dev/video0): Unable to get camera FPS
Webcam capture started (1280x720 @ -1.0fps)
Virtual cam started: /dev/video100 (1280x720 @ 20fps)
Traceback (most recent call last):
  File "/home/admin/test/pyvirtualcam/examples/webcam_filter.py", line 47, in <module>
    raise RuntimeError('Error fetching frame')
RuntimeError: Error fetching frame

I also attempt using libcamerify, which got me further, however I received the following output. Also, my v4l2loopback camera is /dev/video100

libcamerify python webcam_filter.py --camera 0

[10:49:20.873982169] [8178]  INFO Camera camera_manager.cpp:297 libcamera v0.0.5+83-bde9b04f
[10:49:21.000297218] [8183]  INFO RPI vc4.cpp:437 Registered camera /base/soc/i2c0mux/i2c@1/imx708@1a to Unicam device /dev/media4 and ISP device /dev/media1
[10:49:21.307104288] [8186]  INFO Camera camera.cpp:1033 configuring streams: (0) 3840x2160-RGB888
[10:49:21.307797887] [8183]  INFO RPI vc4.cpp:565 Sensor: /base/soc/i2c0mux/i2c@1/imx708@1a - Selected sensor format: 4608x2592-SBGGR10_1X10 - Selected unicam format: 4608x2592-pBAA
[10:49:21.310463858] [8186]  INFO Camera camera.cpp:1033 configuring streams: (0) 3840x2160-RGB888
[10:49:21.310950868] [8183]  INFO RPI vc4.cpp:565 Sensor: /base/soc/i2c0mux/i2c@1/imx708@1a - Selected sensor format: 4608x2592-SBGGR10_1X10 - Selected unicam format: 4608x2592-pBAA
[ WARN:0] global ../modules/videoio/src/cap_gstreamer.cpp (961) open OpenCV | GStreamer warning: Cannot query video position: status=0, value=-1, duration=-1
[10:49:22.243711958] [8186]  INFO Camera camera.cpp:1033 configuring streams: (0) 1280x1080-RGB888
[10:49:22.248753351] [8183]  INFO RPI vc4.cpp:565 Sensor: /base/soc/i2c0mux/i2c@1/imx708@1a - Selected sensor format: 2304x1296-SBGGR10_1X10 - Selected unicam format: 2304x1296-pBAA
[10:49:22.254478935] [8186]  INFO Camera camera.cpp:1033 configuring streams: (0) 1280x1080-RGB888
[10:49:22.255041259] [8183]  INFO RPI vc4.cpp:565 Sensor: /base/soc/i2c0mux/i2c@1/imx708@1a - Selected sensor format: 2304x1296-SBGGR10_1X10 - Selected unicam format: 2304x1296-pBAA
[10:49:22.485378087] [8186]  INFO Camera camera.cpp:1033 configuring streams: (0) 1280x720-RGB888
[10:49:22.486069260] [8183]  INFO RPI vc4.cpp:565 Sensor: /base/soc/i2c0mux/i2c@1/imx708@1a - Selected sensor format: 1536x864-SBGGR10_1X10 - Selected unicam format: 1536x864-pBAA
[10:49:22.487683268] [8186]  INFO Camera camera.cpp:1033 configuring streams: (0) 1280x720-RGB888
[10:49:22.488162426] [8183]  INFO RPI vc4.cpp:565 Sensor: /base/soc/i2c0mux/i2c@1/imx708@1a - Selected sensor format: 1536x864-SBGGR10_1X10 - Selected unicam format: 1536x864-pBAA
[10:49:22.698805011] [8186]  INFO Camera camera.cpp:1033 configuring streams: (0) 1280x720-RGB888
[10:49:22.699408241] [8183]  INFO RPI vc4.cpp:565 Sensor: /base/soc/i2c0mux/i2c@1/imx708@1a - Selected sensor format: 1536x864-SBGGR10_1X10 - Selected unicam format: 1536x864-pBAA
[10:49:22.700812809] [8186]  INFO Camera camera.cpp:1033 configuring streams: (0) 1280x720-RGB888
[10:49:22.701583332] [8183]  INFO RPI vc4.cpp:565 Sensor: /base/soc/i2c0mux/i2c@1/imx708@1a - Selected sensor format: 1536x864-SBGGR10_1X10 - Selected unicam format: 1536x864-pBAA
Webcam capture started (3840x2160 @ 120.0fps)
Virtual cam started: /dev/video100 (3840x2160 @ 20fps)
Traceback (most recent call last):
  File "/home/admin/test/pyvirtualcam/examples/webcam_filter.py", line 56, in <module>
    cam.send(frame)
  File "/usr/local/lib/python3.9/dist-packages/pyvirtualcam/camera.py", line 332, in send
    self._check_frame_shape(frame)
  File "/usr/local/lib/python3.9/dist-packages/pyvirtualcam/camera.py", line 237, in check_frame_shape
    raise ValueError(f"unexpected frame shape: {frame.shape} != {frame_shape}")
ValueError: unexpected frame shape: (720, 1280, 3) != (2160, 3840, 3)