Taking rgb values in a video preview dynamically(i.e run time)

Hello everyone!! I am stuck with a serious problem here! I have my video preview showing up in GUI. I wanted the user to select a particular color or a particular portion of the image by selecting it with mouse. Then I want to take the rgb values of the selected color into the program and operate with it. The part where the user has to select a portion of the image, I have no idea how to do it. I thought of using the crop function, but how to use it in run time. And all of this I have to do it in GUI and while the program is running. Please help.. :)

Answer 1

[Image Analyst]

You can use imrect() or rbbox() to let the user select a box. Not sure if it works over a live image, but you could try it. If it doesn't, then capture a frame and let the user draw over that, then turn the video live again. To get the subimage out, you have to call getsnapshot(), which returns a frame from the live video into a variable in your program. Then you can use imcrop() to extract out that portion if you want, and then do whatever you want with it.

Answer 2

[Anchit Dhar]

You can also try using the ROIPosition property of the videoinput object to get that subimage.