Better printout.

Update OPC UA node only if new shape is different
than last one.

oi-sensor/oi-sensor.py

@@ -70,6 +70,7 @@ async def main():
 
     # Initialize
     result = 0.0
+    shape_change_counter = 0
     result_stack = []
     current_shape = 0.0
 
@@ -157,23 +158,13 @@ async def main():
                         result = 3.0
 
                     # printout
-                    print("\tDetected area (px)=%.2f, result=%d" %(area, result))
+                    print("\tDetected area (px)=%.2f, result=%d, shape changes=%d" %(area, result, shape_change_counter))
 
                     # update list for last X results (FILO)
-                    default_occurence_number = 5
                     result_stack.append(result)
-                    if len(result_stack) > default_occurence_number:
-                        # leave only last X items
-                        result_stack = result_stack[-default_occurence_number:]
-
-                    # to avoid sometimes errors in detection algorithm we change OPC UA node
-                    # variable only if at least we have 2 (40%) of last 5 (100%) items detected as this
-                    # shape. Not complex but avoid false results.
-                    count = result_stack.count(result)
-                    if count >= 2:
-                        # update OPC UA server's node attribute
-                        current_shape = result
-                        await myvar.write_value(result)
+                    current_shape = result
+                    shape_change_counter += 1
+                    await myvar.write_value(result)
 
                     # break current countour detection loop as in this example we care
                     # for first detected SHAPE, we do not expect more shapes
@@ -183,8 +174,10 @@ async def main():
                 # no countours actually detected thus update OPC UA server's node attribute
                 result = 0.0
                 result_stack.append(result)
-                current_shape = result
+                shape_change_counter += 1
                 await myvar.write_value(result)
+                current_shape = result
+                print("\tNo shape detected, result=%d, shape changes=%d" %(result, shape_change_counter))
 
             # show current MASK and camera output windows
             if not headless: