java如何使用javaCV录制视频

Question

我的密码在这里。我用的是安德鲁·戴维森博士的代码

private IplImage picGrab(FrameGrabber grabber, int ID) {
    IplImage im = null;
    try {

        FrameRecorder rec = FrameRecorder.createDefault("vid.avi", 240, 360);
        rec.setVideoCodec(CV_FOURCC('M', 'J', 'P', 'G'));
        rec.setVideoBitrate(16);
        rec.setFrameRate(25);
        rec.setFormat("avi");
        rec.setPixelFormat(1);
        rec.start();

        im = grabber.grab();

        // take a snap
        //   cvSaveImage("capture"+captureNo+".jpg", im);
        rec.record(im);

    } catch (Exception e) {
        e.printStackTrace();
        System.out.println("Problem grabbing image for camera " + ID);
    }
    return im;
}

并发生以下异常

com.googlecode.javacv.FrameRecorder$Exception: cvWriteFrame(): Could not record frame
Problem grabbing image for camera 0
Initializing OpenCV motion detector...
    at com.googlecode.javacv.OpenCVFrameRecorder.record(OpenCVFrameRecorder.java:91)
    at photocapture.MotionPanel.picGrab(MotionPanel.java:181)
    at photocapture.MotionPanel.run(MotionPanel.java:100)
    at java.lang.Thread.run(Thread.java:744)

Answer 1

你需要确保FrameGrabber是有效的。错误消息提示设置可能失败

错误消息通知您执行了以下操作：

FrameGrabber grabber = new OpenCVFrameGrabber(0);

但是设备0不是你的相机

在方法的开头，您应该添加一个安全检查：

 private IplImage picGrab(FrameGrabber grabber, int ID) {

    if (grabber == null) 
    {
        System.out.println("!!! Bad OpenCVFrameGrabber");
        return null;
    }

    // ...