Commit example for bounding box selection

notes/bounding_box.py

@@ -0,0 +1,45 @@
+import cv2
+
+class BoundingBoxWidget(object):
+    def __init__(self):
+        self.original_image = cv2.imread('1.jpg')
+        self.clone = self.original_image.copy()
+
+        cv2.namedWindow('image')
+        cv2.setMouseCallback('image', self.extract_coordinates)
+
+        # Bounding box reference points
+        self.image_coordinates = []
+
+    def extract_coordinates(self, event, x, y, flags, parameters):
+        # Record starting (x,y) coordinates on left mouse button click
+        if event == cv2.EVENT_LBUTTONDOWN:
+            self.image_coordinates = [(x,y)]
+
+        # Record ending (x,y) coordintes on left mouse button release
+        elif event == cv2.EVENT_LBUTTONUP:
+            self.image_coordinates.append((x,y))
+            print('top left: {}, bottom right: {}'.format(self.image_coordinates[0], self.image_coordinates[1]))
+            print('x,y,w,h : ({}, {}, {}, {})'.format(self.image_coordinates[0][0], self.image_coordinates[0][1], self.image_coordinates[1][0] - self.image_coordinates[0][0], self.image_coordinates[1][1] - self.image_coordinates[0][1]))
+
+            # Draw rectangle 
+            cv2.rectangle(self.clone, self.image_coordinates[0], self.image_coordinates[1], (36,255,12), 2)
+            cv2.imshow("image", self.clone) 
+
+        # Clear drawing boxes on right mouse button click
+        elif event == cv2.EVENT_RBUTTONDOWN:
+            self.clone = self.original_image.copy()
+
+    def show_image(self):
+        return self.clone
+
+if __name__ == '__main__':
+    boundingbox_widget = BoundingBoxWidget()
+    while True:
+        cv2.imshow('image', boundingbox_widget.show_image())
+        key = cv2.waitKey(1)
+
+        # Close program with keyboard 'q'
+        if key == ord('q'):
+            cv2.destroyAllWindows()
+            exit(1)