From d54f1b9dcaf75ebe8af29d12defb6abf0e3ea9fc Mon Sep 17 00:00:00 2001
From: Jens Ahrensfeld <jens@jayfield.org>
Date: Sat, 22 Oct 2016 17:40:35 +0000
Subject: [PATCH] - more FPS by median blur on ROI only

git-svn-id: http://moon:8086/svn/software/trunk/projects/opencv@336 b431acfa-c32f-4a4a-93f1-934dc6c82436
---
 lasertrack.py | 34 ++++++++++++++++++++++++++++------
 1 file changed, 28 insertions(+), 6 deletions(-)

diff --git a/lasertrack.py b/lasertrack.py
index f37ce3a..a3cc7e1 100755
--- a/lasertrack.py
+++ b/lasertrack.py
@@ -65,16 +65,27 @@ class MyRgbProcess(RgbProcess):
 			gray = cv2.cvtColor(data,cv2.COLOR_BGR2GRAY)
 
 			img1_objects = data.copy()
-			# Min / max approach
-			gray_blurred = cv2.medianBlur(gray,3)
-			minVal, maxVal, minLoc, maxLoc = cv2.minMaxLoc(gray_blurred)
+			# Min / max on whole image
+			minVal, maxVal, minLoc, maxLoc = cv2.minMaxLoc(gray)
 			x = maxLoc[0]
 			y = maxLoc[1]
+			# get ROI with size roi_size centered at maxLoc
+			roi_size = 21
+			roi = self.getROI(gray, x, y, roi_size, roi_size)
+			# do the blur on ROI
+			roi_blurred = cv2.medianBlur(roi,5)
+			# Re-calculate centers on blurred image
+			minVal, maxVal, minLoc, maxLoc = cv2.minMaxLoc(roi_blurred)
+			# adjust centers of unfiltered image (x, y are in global pixel space)
+			x += maxLoc[0] - int((roi_size-1)/2)
+			y += maxLoc[1] - int((roi_size-1)/2)
+
+			# Calculated dot fall-of over different windows
 			rect = None
 			state = 0
 			ref_color = 1
-			for roi_size in range(1,15):
-				roi = gray[y-roi_size:y+roi_size, x-roi_size:x+roi_size]
+			for roi_size in range(3,33,2):
+				roi = self.getROI(gray, x, y, roi_size, roi_size)
 				mean_color = cv2.mean(roi)
 				if state == 0:
 					ref_color = mean_color[0]
@@ -86,7 +97,8 @@ class MyRgbProcess(RgbProcess):
 					if km < 0.7:	
 						rect = [(x-roi_size, y-roi_size),(x+roi_size, y+roi_size)]
 						break
-				
+			
+			# Is object found?
 			if rect is not None:
 				if not self.isVisible:
 					print ("Visible")
@@ -101,6 +113,7 @@ class MyRgbProcess(RgbProcess):
 					self.sendBrick(0, 0)
 				self.isVisible = False
 			
+			# Update preview
 			showFrame = False
 			if self.frameSkipCounter > 0:
 				self.frameSkipCounter -= 1
@@ -122,6 +135,15 @@ class MyRgbProcess(RgbProcess):
 			data = struct.pack("f", errorY)
 			ev3.system_command.write_mailbox(self.brick, 'ErrorY', data)
 
+	def getROI(self, img, x, y, w, h):
+		w2 = int((w-1)/2)
+		h2 = int((h-1)/2)
+		xmin = max(0, x-w2)
+		ymin = max(0, y-h2)
+		xmax = min(self.res[0]-1, x+w2)
+		ymax = min(self.res[1]-1, y+h2)
+		return img[ymin:ymax, xmin:xmax] 
+		
 if with_ev3:
 	# Connect to brick
 	with ev3.EV3() as brick: