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Hey @luigidr
at FXHelloCVController.java Lines 160-168 you convert a mat to a JavaFX Image. Sometimes this fct (random time) will not convert a mat correctly and the ImageViewer stops working(Will not receive a correct image anymore). Atm i dont know why, but i will find it out. I found this code which works well and is more performant.
http://stackoverflow.com/questions/29120869/how-to-convert-matopencv-to-imagejavafx
Performance: Mat -> BufferedImage -> JavaFXImage http://cell0907.blogspot.de/2013/12/from-mat-to-bufferedimage.html
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private Image mat2Image(Mat frame) {
try{
 return SwingFXUtils.toFXImage(matToBufferedImage(frame),null);
} catch (Exception e) {
 System.out.println("Cant convert mat");
 return null;
}
}

public BufferedImage matToBufferedImage(Mat matBGR){   
          int width = matBGR.width(), height = matBGR.height(), channels = matBGR.channels() ;  
          byte[] sourcePixels = new byte[width * height * channels];  
          matBGR.get(0, 0, sourcePixels);  
              //TYPE_BYTE_GRAY - gray images , TYPE_3BYTE_BGR - 3 Channles
          image = new BufferedImage(width, height, BufferedImage.TYPE_3BYTE_BGR);  
          final byte[] targetPixels = ((DataBufferByte) image.getRaster().getDataBuffer()).getData();  
          System.arraycopy(sourcePixels, 0, targetPixels, 0, sourcePixels.length);  
          return image;  
}  

I am trying to display IplImage on imageview in application. But Imageview_id.setImage() allows only Image obj as parameter. Is there is another method to display iplImage in imageview ? or How to convert IplImage to Image?

The setFrametoImageView() and updateUIObjects() method could be replaced by a single method that uses generics to avoid code duplication.

Errors in FXHelloCVController.java

					Image imagetoshow = Utils.mat2Image(frame);
					updateImageView(currentFrame, imagetoshow);

Error: The method mat2Image(Mat) is undefined for the type Utils

private void updateImageView(ImageView view, Image image){
Utils.onFXThread(view.imageProperty(), image);

Error : The method onFXThread(ObjectProperty, Image) is undefined for the type Utils

I have done everything according to the doc.I can find a file named libopencv_java310.so in /path/to/opencv-3.1.0/build/lib.
Also ,I configured the Native library path to /path/to/opencv-3.1.0/build/lib in eclipse.

but after running he HelloCV project,an error below occured:

Exception in thread "main" java.lang.UnsatisfiedLinkError: no opencv_java310 in java.library.path.

There is a huge memory leak here. Im trying to fix, but even calling Mat.release(), didn't worked. I think may there is an issue calling read(Mat mat) from another thread.

	private Mat grabFrame()
	{
		// init everything
		Mat frame = new Mat();
		
		// check if the capture is open
		if (this.capture.isOpened())
		{
			try
			{
				// read the current frame
				this.capture.read(frame);
				
				// if the frame is not empty, process it
				if (!frame.empty())
				{
					Imgproc.cvtColor(frame, frame, Imgproc.COLOR_BGR2GRAY);
				}
				
			}
			catch (Exception e)
			{
				// log the error
				System.err.println("Exception during the image elaboration: " + e);
			}
		}
		
		return frame;
	}

Hi, I have used netbeans instead of eclipse for the project, but I have followed everything mentioned in the tutorial. Yet I get a "Location is not set" error, and here is a printscreen of what I am seeing exactly. Can I know why is the error being caused since I do not really get it and how can it be fixed.

Edited: I have created another package for the utils.Utils but I assume that has nothing to do with it.

Generally, it is "better" to prefer the Java Executor to classical Thread.

If possible, replace the processFrame thread with an Executor object or with a JavaFX object suitable for concurrency (i.e., from javafx.concurrent).

FXHelloCVController.java Line 72. It's not allowed to set a new Image (ImageViewer) from another Thread(Runnable).
Possible fix:

FXHelloCVController.java Line72
setFrametoImageView(imageToShow) instead of currentFrame.setImage(imageToShow);

FXHelloCVController.java Line 113

private void setFrametoImageView(Image frame){
   Platform.runLater(() -> {
      currentFrame.setImage(frame);
      //set Image height/width by window size
   });
}

InvocationTargetException is thrown in creating an instance of VideoCapture class.

Operating System: Ubuntu 16.04
JDK Version : JDK 1.8.152

The FPS calculation present in the application doesn't work with the latest version of Java 8/JavaFX/OpenCV 3.1. It always shows "0.0".

It seems that, for live videos, the method used in the code doesn't work (it should work for "offline" videos). Amend or remove the FPS calculation.