VNCScreen.wait() does not catch image change

just checked - works as expected (when obeying the special aspects of VNCScreen and dedicated regions/locations)

please post some offending snippet.

I tried a couple options, both have the same result.
option 1:
public Match waitForImage(VNCScreen vnc_old, String image, Region reg, double waitTimeout, float score) {
  System.out.println("Waiting for image: " + image + " in a specific region: " + reg.getX() + ", " + reg.getY() + " " + reg.getW() + "x" + reg.getH());

  vnc_old.setRect(reg.x, reg.y, reg.w, reg.h);

  Pattern pat = new Pattern(image);
  pat.similar(score);
  Match found = null;

  try {
   found = vnc_old.wait(image, waitTimeout);
   System.out.println("Match: " + found.getScore());
   System.out.println("Found image region: " + found.x + "," + found.y + " " + found.w + "x" + found.h);
  } catch (FindFailed e) {
   e.printStackTrace();
   screenShot(vnc_old, reg);
   throw new RuntimeException("Failed to find a match for image and click it. " + image);
  }

  vnc_old.hover(); // printing found region coordinates
  return found;
 }

option 2:
public Match waitForImage(String image, Region reg, double waitTimeout, float score) {
  int port = Integer.parseInt(5950);
  VNCScreen vnc = connectVNC(HOST, port, PASSWORD, 10, 5000);

  System.out.println("Waiting for image: " + image + " in a specific region: " + reg.getX() + ", " + reg.getY() + " " + reg.getW() + "x" + reg.getH());

  vnc.setRect(reg.x, reg.y, reg.w, reg.h);

  Pattern pat = new Pattern(image);
  pat.similar(score);
  Match found = null;

  try {
   found = vnc.wait(image, waitTimeout);
   System.out.println("Match: " + found.getScore());
   System.out.println("Found image region: " + found.x + "," + found.y + " " + found.w + "x" + found.h);
  } catch (FindFailed e) {
   e.printStackTrace();
   screenShot(vnc, reg);
   throw new RuntimeException("Failed to find a match for image and click it. " + image);
  }

  vnc.hover(); // printing found region coordinates
  return found;
 }

Commenting vnc.setRect(reg.x, reg.y, reg.w, reg.h); also does not bring any changes to final result.

I have no idea, what your problems are.

My test with the latest build 1.1.4: (transscripted to my habits)

The image to search for is seen near the top of the remote screen.

      //public Match waitForImage(VNCScreen vnc_old, String image, Region reg, double waitTimeout, float score) {
      //System.out.println("Waiting for image: " + image + " in a specific region: " + reg.getX() + ", " + reg.getY() + " " + reg.getW() + "x" + reg.getH());

      VNCScreen.startUp(0); //do not wait after start (standard would be 3 secs)
      VNCScreen vs = VNCScreen.start("192.168.2.121");

      Region reg = new Region(0, 0, 1600, 300);
      vs.setRect(reg.x, reg.y, reg.w, reg.h);

      String vimg = "vncChrome";
      Pattern pat = new Pattern(vimg);
      //pat.similar(score); //match score is > 0.99 ;-)
      Match found = null;

      try {
        found = vs.wait(pat); //standard waiting 3 secs
// System.out.println("Match: " + found.getScore());
// System.out.println("Found image region: " + found.x + "," + found.y + " " + found.w + "x" + found.h);
        p("found: %s", found); //my formatting print function
      } catch (FindFailed e) {
        log(-1, "not found: %s", pat); // class Debug
// e.printStackTrace();
// screenShot(vs, reg);
// throw new RuntimeException("Failed to find a match for image and click it. " + image);
      }
      //vs.hover(); // printing found region coordinates
      //return found;
      // }

The printout when using setRect():
found: M[836,3 74x88]@S(NonLocal, 1280x300) S:1,00 C:873,47 [158 msec]

the search-time will be about 1 sec with fullscreen (no setRect())

BTW: setRect() is not recommended for restricting the search region for one search.
Better is to use the class Region:

Region reg = vnc.newRegion(givenRegion); // dedicates the Region to the given VNCScreen
found = reg.wait(image);

RaiMan, are there any log records, which could help? And which level if so?

Debug.on(3); //switch on normal debug level
Debug.off(); //switch off again

yeah, I've found this in documentation, but does debug has records about screen capture?

With the latest build from today, this snippet: (build#167)

      Debug.on(3);
      VNCScreen vs = VNCScreen.start("192.168.2.121");
      Region reg = vs.newRegion(0, 0, 1500, 300);
      reg.find("vncChrome");
     System.exit(0);

gave this log:

CConnection: Server supports RFB protocol version 3.8
CConnection: Using RFB protocol version 3.8
[4662 debug] VNCScreen: start: R[0,0 1920x1200]@S(VNC 192.168.2.121:5900)
[4733 debug] Image: loaded: vncChrome.png (file:/Users/raimundhocke/IdeaProjects/sikulix1/API/src/main/resources/ImagesAPI/vncChrome.png)
[4733 debug] Image: cached: vncChrome.png (19 KB) (# 1 KB 19 -- 0 % of 64 MB)
[4733 debug] Region: find: waiting 0 secs for vncChrome.png to appear in R[0,0 1500x300]@S(VNC 192.168.2.121:5900)
[4737 debug] VNCScreen: capture: (0,0) 1500x300 on R[0,0 1920x1200]@S(VNC 192.168.2.121:5900)
[4743 debug] RunTimeAPI: libsExport: folder exists: /Users/raimundhocke/Library/Application Support/Sikulix/SikulixLibs (1.1.4 - 201812311549)
[4746 debug] RunTimeAPI: loadLib: libopencv_java342.dylib (success)
[4748 debug] Finder2: makeMat: INT_RGB (1500x300)
[4762 debug] Finder2: makeMat: 3BYTE_BGR (74x88)
[4764 debug] Finder2: doFind: start (stdDev: 161,6029 mean: 317,441032)
[4814 debug] Finder2: doFind: in original: %100,0000 (?70) 48 msec
[4815 debug] Finder2: doFind: end 49 msec
[4818 debug] Region: find: vncChrome.png appeared (M[836,3 74x88]@S(VNC 192.168.2.121:5900) S:1,00 C:873,47 [83 msec])
[4819 debug] RunTimeAPI: ***** final cleanup at System.exit() *****
[4819 debug] VNCScreen: stopping all
[4819 debug] VNCScreen: stopping: R[0,0 1920x1200]@S(VNC 192.168.2.121:5900)
[4834 debug] FileManager: deleteFileOrFolder:
/var/folders/pc/t43tqvr56xx7kxz3m6z5g4rw0000gn/T/Sikulix_694096369