optimizing calibration for android

android/android-jni/jni/Calibration.cpp

@@ -160,34 +160,9 @@ bool Calibration::detectAndDrawChessboard(int idx, image_pool* pool)
   if (grey.empty())
     return false;
   vector<Point2f> corners;
-  IplImage iplgrey = grey;
-  patternfound = cvCheckChessboard(&iplgrey, patternsize);
-  if (!patternfound)
-    return false;
-
-  float factor = grey.cols / 320.0f;
-  if (factor < 1)
-    factor = 1;
-  cv::Size r_size = cv::Size(grey.cols / factor, grey.rows / factor);
-  Mat grey_sub;
-  while (patternfound && (r_size.width < grey.size().width))
-  {
-    cv::resize(grey, grey_sub, r_size);
-    patternfound = findChessboardCorners(grey_sub, patternsize, corners);
-    if (patternfound)
-    {
-      r_size.width *= 2;
-      r_size.height *= 2;
-    }
-    else
-    {
-      return false;
-    }
-  }
-
-  // hopefully if we're going to fail we fail on a smaller size image in the while-loop
-  patternfound = findChessboardCorners(grey, patternsize, corners);
 
+  patternfound = findChessboardCorners(grey, patternsize, corners,CALIB_CB_FILTER_QUADS + CALIB_CB_ADAPTIVE_THRESH + CALIB_CB_NORMALIZE_IMAGE
+                                                + CALIB_CB_FAST_CHECK);
   Mat img = pool->getImage(idx);
 
   if (corners.size() < 1)

android/android-jni/res/values/chessnumbers.xml

 <?xml version="1.0" encoding="utf-8"?>
 <resources>
 <string-array name="chesssizes">
+<item>2</item>
 <item>3</item>
 <item>4</item>
 <item>5</item>

android/android-jni/res/values/settingnumbers.xml

@@ -3,7 +3,7 @@
 <string-array name="image_sizes">
 <item>320x240</item>
 <item>400x300</item>
-<item>600x400</item>
+<item>640x480</item>
 <item>800x600</item>
 <item>1000x800</item>
 </string-array>

android/android-jni/src/com/opencv/calibration/ChessBoardChooser.java

@@ -17,7 +17,7 @@ public class ChessBoardChooser extends Activity {
 	public static final String CHESS_SIZE = "chess_size";
 	public static final int DEFAULT_WIDTH = 6;
 	public static final int DEFAULT_HEIGHT = 8;
-	public static final int LOWEST = 3;
+	public static final int LOWEST = 2;
 
 	class DimChooser implements OnItemSelectedListener {
 		private String dim;

android/android-jni/src/com/opencv/camera/CameraConfig.java

@@ -51,8 +51,8 @@ public class CameraConfig extends Activity {
 		// Restore preferences
 		SharedPreferences settings = ctx.getSharedPreferences(CAMERA_SETTINGS,
 				0);
-		size[0] = settings.getInt(IMAGE_WIDTH, 600);
-		size[1] = settings.getInt(IMAGE_HEIGHT, 400);
+		size[0] = settings.getInt(IMAGE_WIDTH, 640);
+		size[1] = settings.getInt(IMAGE_HEIGHT, 480);
 
 	}