Turning your webcam into a simple RGB light sensor sampling at the framerate.

Install it in your local package repository with --user otherwise become admin and omit it:

setup.py install --user

pip3 install opencv-contrib-python
pip3 install opencv-python

import webcam2rgb

camera = webcam2rgb.Webcam2rgb()

def hasData(retval, data):

where data is an BGR tupel and retval contains any error from openCV

camera.start(callback = hasData)

the callback is then called at the framerate of the camera

This method has the following optional arguments:

• cameraNumber=0 starts acquisition from camera number cameraNumber
• width = None tries to set the width of the camera acquisition
• height = None tries to set the height of the camera acquisition
• fps = None tries to set the framerate
• directShow = False switches on Direct Show under Windows

camera.stop()

fs = camera.cameraFs()

Just run demo.py. It plots the R,G,B channels in three plot windows.

Start your program from the (Anaconda-) console / terminal and never within Spyder. Here is an example for Windows

    (base) D:\>
    (base) D:\>cd webcam2rgb
    (base) D:\webcam2rgb>python demo.py

The problem with Spyder is that it won't let your Python program terminate properly which leaves the video camera in an undefined state. If you then re-run your program it won't be able to talk to your camera. In the worst case you need to reboot your computer. Bottomline: use Spyder for editing, run the program from the console / terminal.

Under Windows, sometimes the camera initilisation does not open the camera correctly - shown by a 0Hz readout from camera.cameraFs(). If this happens the camera needs to be reopened manually. Try using the directShow = True parameter to use the Direct Show backend.