OpenCV 2.4.4 Java - 抓取网络摄像头图片/流(OSX)

Question

我是Stackoverflow和OpenCV编程领域的新手.我用OpenCV Bindings for Java(opencv.org官员,而不是JavaCV)制作了一些项目,比如通过ORB和SURF功能进行对象识别,处理图像.一切还好.现在我正在转向视频流中的对象识别.我想从网络摄像头抓取流并应用对象识别.我不是Java大师,所以我在OpenCV中找到了VideoCapture类,但是我无法从相机中获取图片.

我在OSX Mountain Lion中使用OpenCV 2.4.4绑定在Eclipse中运行我的项目.

控制台中的结果:

Hello, OpenCV
Camera OK?
Frame Obtained
Captured Frame Width 0
Invalid memory access of location 0x7fae00000000 rip=0x7fff8b4c5263

代码:

import org.opencv.core.Mat;
import org.opencv.highgui.Highgui;
import org.opencv.highgui.VideoCapture;

public class Webcam {

    public static void main (String args[]){

    System.out.println("Hello, OpenCV");
    // Load the native library.
    System.loadLibrary("opencv_java244");

    VideoCapture camera = new VideoCapture(0);
    camera.open(0); //Useless
    if(!camera.isOpened()){
        System.out.println("Camera Error");
    }
    else{
        System.out.println("Camera OK?");
    }

    Mat frame = new Mat();

    //camera.grab();
    //System.out.println("Frame Grabbed");
    //camera.retrieve(frame);
    //System.out.println("Frame Decoded");

    camera.read(frame);
    System.out.println("Frame Obtained");

    /* No difference
    camera.release();
    */

    System.out.println("Captured Frame Width " + frame.width());

    Highgui.imwrite("camera.jpg", frame);
    System.out.println("OK");
    }
}

Answer 1

问题只是相机需要时间来初始化.我已经添加

Thread.sleep(1000);

后

VideoCapture camera = new VideoCapture(0);