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### How to use external camera or webcam with cone_detectortf ?

Hello,

I'm relatively new to oOpenCVand I"m trying to use this GitHub code in python: https://github.com/fdiazgon/cone-detector-tf

Everything works fine with different video files, but when I try to use my webcam I get the following error :

Frames per second using video.get(cv2.CAP_PROP_FPS) : 29.97002997 Capturing 120 frames Time taken: 9.97166395187 seconds Estimated frames per second: 12.0340998833 Traceback (most recent call last): File "cone_detectorcam.py", line 169, in <module> main() File "cone_detectorcam.py", line 126, in main boxes = np.vstack(boxes) File "/Library/Frameworks/Python.framework/Versions/2.7/lib/python2.7/site-packages/numpy/core/shape_base.py", line 283, in vstack return _nx.concatenate([atleast_2d(_m) for _m in tup], 0) ValueError: need at least one array to concatenate

I maybe think it is a resolution problem but I'm not able to fix it, Hopely someone is able to help me :)

thanks in regards,

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### How to use external camera or webcam with cone_detectortf ?

Hello,

I'm relatively new to oOpenCVand I"m trying to use this GitHub code in python: https://github.com/fdiazgon/cone-detector-tf

Everything works fine with different video files, but when I try to use my webcam I get the following error :

Frames per second using video.get(cv2.CAP_PROP_FPS) : 29.97002997
Capturing 120 frames
Time taken: 9.97166395187 seconds
Estimated frames per second: 12.0340998833
Traceback (most recent call last):
File "cone_detectorcam.py", line 169, in <module>
main()
File "cone_detectorcam.py", line 126, in main
boxes = np.vstack(boxes)
File "/Library/Frameworks/Python.framework/Versions/2.7/lib/python2.7/site-packages/numpy/core/shape_base.py", line 283, in vstack
return _nx.concatenate([atleast_2d(_m) for _m in tup], 0)
ValueError: need at least one array to concatenateconcatenate


I maybe think it is a resolution problem but I'm not able to fix it, Hopely someone is able to help me :)

thanks in regards,