Running a private code that reads the data from the Webcam, I get the following error:
Loading weights from handyolo/weights/000010.weights... Done! INFO:exp11_fm64_iter1_l2_rmsprop_feaadd_zrel3_transformer_Test:Creating instance of the ImageHeatmapsPose2dZrelZAll_FPN model. INFO:exp11_fm64_iter1_l2_rmsprop_feaadd_zrel3_transformer_Test:n_iter: 1 INFO:exp11_fm64_iter1_l2_rmsprop_feaadd_zrel3_transformer_Test:improvement_per_itr: 0.01 INFO:exp11_fm64_iter1_l2_rmsprop_feaadd_zrel3_transformer_Test:beta: 5.0 INFO:exp11_fm64_iter1_l2_rmsprop_feaadd_zrel3_transformer_Test:Creating instance of L1 Loss. VIDEOIO ERROR: V4L2: Pixel format of incoming image is unsupported by OpenCV Unable to stop the stream: Device or resource busy Error getting frame from device 0 Here is the camera info:
$ v4l2-ctl -d /dev/video0 --all Driver Info (not using libv4l2): Driver name : uvcvideo Card type : HD Pro Webcam C920 Bus info : usb-0000:00:14.0-9 Driver version: 4.13.13 Capabilities : 0x84200001 Video Capture Streaming Extended Pix Format Device Capabilities Device Caps : 0x04200001 Video Capture Streaming Extended Pix Format Priority: 2 Video input : 0 (Camera 1: ok) Format Video Capture: Width/Height : 320/180 Pixel Format : 'YUYV' Field : None Bytes per Line : 640 Size Image : 115200 Colorspace : sRGB Transfer Function : Default YCbCr Encoding : Default Quantization : Default Flags : Crop Capability Video Capture: Bounds : Left 0, Top 0, Width 320, Height 180 Default : Left 0, Top 0, Width 320, Height 180 Pixel Aspect: 1/1 Selection: crop_default, Left 0, Top 0, Width 320, Height 180 Selection: crop_bounds, Left 0, Top 0, Width 320, Height 180 Streaming Parameters Video Capture: Capabilities : timeperframe Frames per second: 30.000 (30/1) Read buffers : 0 brightness (int) : min=0 max=255 step=1 default=128 value=128 contrast (int) : min=0 max=255 step=1 default=128 value=128 saturation (int) : min=0 max=255 step=1 default=128 value=128 white_balance_temperature_auto (bool) : default=1 value=1 gain (int) : min=0 max=255 step=1 default=0 value=132 power_line_frequency (menu) : min=0 max=2 default=2 value=2 white_balance_temperature (int) : min=2000 max=6500 step=1 default=4000 value=3255 flags=inactive sharpness (int) : min=0 max=255 step=1 default=128 value=128 backlight_compensation (int) : min=0 max=1 step=1 default=0 value=0 exposure_auto (menu) : min=0 max=3 default=3 value=3 exposure_absolute (int) : min=3 max=2047 step=1 default=250 value=333 flags=inactive exposure_auto_priority (bool) : default=0 value=1 pan_absolute (int) : min=-36000 max=36000 step=3600 default=0 value=0 tilt_absolute (int) : min=-36000 max=36000 step=3600 default=0 value=0 focus_absolute (int) : min=0 max=250 step=5 default=0 value=0 flags=inactive focus_auto (bool) : default=1 value=1 zoom_absolute (int) : min=100 max=500 step=1 default=100 value=100 led1_mode (menu) : min=0 max=3 default=0 value=3 led1_frequency (int) : min=0 max=255 step=1 default=0 value=0 $ v4l2-ctl -d /dev/video0 --list-formats ioctl: VIDIOC_ENUM_FMT Index : 0 Type : Video Capture Pixel Format: 'YUYV' Name : YUYV 4:2:2 Index : 1 Type : Video Capture Pixel Format: 'H264' (compressed) Name : H.264 Index : 2 Type : Video Capture Pixel Format: 'MJPG' (compressed) Name : Motion-JPEG How can I fix this?
Also, trying to get the video from guvcview I get the following error:
$ guvcview GUVCVIEW: version 2.0.2 GUVCVIEW: couldn't open /home/mona/.config/guvcview2/video0 for read: 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 V4L2_CORE: (UVCIOC_CTRL_MAP) Error: No such file or directory ALSA lib pcm.c:2266:(snd_pcm_open_noupdate) Unknown PCM cards.pcm.rear ALSA lib pcm.c:2266:(snd_pcm_open_noupdate) Unknown PCM cards.pcm.center_lfe ALSA lib pcm.c:2266:(snd_pcm_open_noupdate) Unknown PCM cards.pcm.side ALSA lib pcm_route.c:867:(find_matching_chmap) Found no matching channel map 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 4294967295, skipping unlock JackShmReadWritePtr::~JackShmReadWritePtr - Init not done for 4294967295, skipping unlock 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 Gtk-Message: GtkDialog mapped without a transient parent. This is discouraged. V4L2_CORE: (VIDIOC_S_PARM) error: Device or resource busy V4L2_CORE: Unable to set 1/30 fps GUVCVIEW: (status) saving video to /home/mona/my_video-1.mkv ENCODER: add stream 0 to stream list ENCODER: add stream 1 to stream list ENCODER: (matroska) add seekhead entry 0 (max 10) ENCODER: (matroska) add seekhead entry 1 (max 10) AUDIO: (portaudio) Aborting audio stream AUDIO: Closing audio stream... ENCODER: (matroska) closing context ENCODER: (matroska) closing cluster ENCODER: (matroska)write seekhead ENCODER: (matroska) end duration = 6922 (6922.000000) ^CGUVCVIEW Caught signal 2 ^CGUVCVIEW Caught signal 2 so far unplugged and plugged back the Webcam, used cheese and now I get video:
$ cheese & But now, running the code I get this new error:
VIDEOIO ERROR: V4L: index 0 is not correct! Error getting frame from device 0 Before this, the camera light was blue and now it has no light turned on.
so my Webcam is on device 014 and I use it for video capture in OpenCV:
$ sudo lsusb | grep -i cam Bus 003 Device 014: ID 046d:082d Logitech, Inc. HD Pro Webcam C920 Here is the code:
if USE_CAMERA: cap = cv.VideoCapture(args.device) And I pass 014 as argument to it. I get this error:
VIDEOIO ERROR: V4L: index 14 is not correct! Error getting frame from device 14 3 Answers
First unplugged and plugged the Webcam USB and then used the following command to find which device number is the Webcam and used the appropriate port number:
$ ls /dev/video* /dev/video1 In my case it was OpenCV version issue. I downgraded its version from 4.0 to 3.4 and it worked for me. Since I installed my OpenCv with pip before, I downgraded it in the following way:
pip uninstall opencv-python pip install opencv-python==3.4.0.12 The reason for this error is OpenCV not releasing the camera. when you start capturing camera frames using cap= cv2.VideoCapture(0) and release the camera with cap.release() in background our camera is still working.
one method to again use the camera without an error is simply rebooting Ubuntu.
if you do not want to reboot every time you run the code, what you can do is raising a KeyboardInterrupt at the very end of the code by raise KeyboardInterrupt this way the camera stream is properly closed. this may be not the safest way. but this works.
