OpenCV 3.0 Computer Vision with Java

Capturing a video from a camera

The process of capturing frames from a webcam is very complex and it involves hardware details as well as heavy decoding or decompression algorithms. Fortunately, OpenCV has wrapped it all in a simple, yet powerful class called VideoCapture. This class not only grabs an image from a webcam, but also reads video files. In case more advanced access to a camera is required, you may want to use its specialized drivers.

You can think of a video stream as a series of pictures and you can retrieve each image in Mat and process it as you like. In order to use the VideoCapture class to capture a webcam stream, you need to instantiate it using the VideoCapture(int device) constructor. Note that the constructor parameter refers ...