read webcam with opencv

[study24816]

Thanks you all for some good guides around here!

I've tried to implement with these and found some problems:
+ the framework of ChrisW67 is good but in OpenCV, the SLOT capture() needs to hold an object Videocapture (an OpenCV class) to avoid repeating creating this class inside SLOT capture() -> by now, I still don't know how to work around this

Besides, I work with both Qt and OpenCV new versions Qt 4 and OpenCV 2.3.1 respectively and I had to do some editings to recode your ideas

** Solution:
I've just found it:
+ create a class variable VideoCapture cap
+ open it in class constructor with cap.Open(0) // default device
+ then, it can be used in SLOT without having to pass this 'cap' variable around

=> DONE already !! thanks all!