first update yourcode to opencv 4.9

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Why opencv 4.7.0 (december 2022)?
Take a look at https://github.com/opencv/opencv/wiki/ChangeLog#version490 and you will see how many bug and patch since opencv 4.7.
Yolov7 (https://github.com/WongKinYiu/yolov7) is two years old.

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Hello
I updated opencv to 4.9.0, and the previous problems did not occur. Thank you for your assistance.

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Hello
I have updated my opencv version to 4.7.0 but it still has this problem！

$ conda list opencv

packages in environment at /home/mk/anaconda3:

Name Version Build Channel

libopencv 4.7.0 py311h7a0761e_1 conda-forge
opencv 4.7.0 py311h38be061_1 conda-forge
py-opencv 4.7.0 py311h781c19f_1 conda-forge
----------------------------problem----------------------------------------
(base) mk@mk-ROG-Flow-X16-GV601VI-GV601VI:~/visp-ws/visp-build/tutorial/detection/dnn$ ./tutorial-dnn-object-detection-live --input-json ./default_yolov7.json
Video device : 0
Label file (optional): None
[ WARN:0] global ./modules/videoio/src/cap_gstreamer.cpp (1100) open OpenCV | GStreamer warning: Cannot query video position: status=0, value=-1, duration=-1
Model : /home/mk/visp-ws/visp-build/tutorial/detection/dnn/yolov7/yolov7-tiny.onnx
Type : yolov7
Config (optional): "None"
Framework (optional): onnx
Width x Height : 640 x 640
Mean RGB : 0.000000 0.000000 0.000000
Scale : 0.003922
Swap RB? : false
Confidence threshold : 0.500000
NMS threshold : 0.500000
Filter threshold : disabled

Caught an exception trying to run inference:
OpenCV(4.5.4) ./modules/dnn/include/opencv2/dnn/shape_utils.hpp:170: error: (-215:Assertion failed) start <= (int)shape.size() && end <= (int)shape.size() && start <= end in function 'total'

Cuda and/or GPU driver might not be correctly installed. Setting preferable backend to CPU and trying again.
terminate called after throwing an instance of 'cv::Exception'
what(): OpenCV(4.5.4) ./modules/dnn/include/opencv2/dnn/shape_utils.hpp:170: error: (-215:Assertion failed) start <= (int)shape.size() && end <= (int)shape.size() && start <= end in function 'total'

Aborted (core dumped)

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