Calculating Light Intensity through video

Using a camera, how can I detect light intensity and use that as a marker. Can someone guide me to a thread that could help me develop a script for this.

Thank you

[YOGITAA YOGITAA]

Could you please share the code?

[Image Analyst]

@YOGITAA YOGITAA See attached. Start a new question if you have question.

Answer 1

[Image Analyst]

Use the Image Acquisition Toolbox and call getsnapshot(). Then get the intensity from whatever pixels you want in the image.

[Andrew]

Thank you for the reply. Unfortunately, I do not have access to that toolbox. Is there any way I can achieve this from scratch? Maybe get the video stream as a matrix and calculate the intensity through that?

Thanks

[Image Analyst]

With Release R2014a you can now access the webcam without the Image Acquisition Toolbox. See http://www.mathworks.com/support/2014a/matlab/8.3/demos/webcam-support.html