I've been working on training an object-detector with OpenCV 2 (using opencv_traincascade) and have had good success implementing the resulting XML file in Python.  I was sad to find that installing OpenCV 2 broke the Processing library, so I tried installing the JavaCVPro library.  While it works using an image of a face and one of the pre-built cascade files, it throws a weird error and quits when I try to use my XML file:

1. import hypermedia.video.*;
   
2. import java.awt.Rectangle;
   
3. 
   
4. String imageFilename = "face.jpg";
5. String cascadeFilename = "cascade.xml";
6. OpenCV cv;
   
7. PImage img;
   
8. 
   
9. void setup() {
   
10.   img = loadImage(imageFilename);
    
11.   size(img.width, img.height);
    
12.   image(img, 0,0);
    
13.  
    
14.   cv = new OpenCV(this);
    
15.   cv.allocate(img.width, img.height);
    
16.   cv.copy(img.pixels, img.width, 0,0, img.width, img.height, 0,0, img.width, img.height);
    
17.   cv.convert(GRAY);
18. 
    
19.   //cv.cascade(sketchPath("") + "frontalface.xml");      // this cascade works...
    
20.   cv.cascade(sketchPath("") + cascadeFilename);      // mine doesn't...
    
21.  
    
22.   Rectangle[] found = cv.detect(1.2, 2, OpenCV.HAAR_DO_CANNY_PRUNING, 60,60);
    
23.   println("Found: " + found.length);
    
24.   stroke(255);
    
25.   noFill();
    
26.   for (Rectangle f : found) {
    
27.     rect(f.x, f.y, f.width, f.height);
    
28.   }
    
29. }
    
30. 
    
31. public void stop() {
    
32.   cv.stop();
    
33.   super.stop();
    
34. }

While my cascade works great in Python, it throws this weird error:

1. OpenCV Error: Unspecified error (The node does not represent a user object (unknown type?)) in cvRead, file /Users/palimpseste/Development/OpenCV/opencv-2.x/svn/OpenCV/modules/core/src/persistence.cpp, line 4811
   terminate called throwing an exception

I did have some trouble getting the Python code to work until I changed cv.cascade to cv2.CascadeClassifier (apparently this has to do with the method for training in cv1 vs cv2).  I wonder if all of the cv2 code has been updated in the library?

Any suggestions would be great - I like using and teaching Processing, so getting this working again would be fantastic.