From f4d8c80edec028dcc5e9ff6c54d7307af2ce514c Mon Sep 17 00:00:00 2001
From: Jens Ahrensfeld <jens@jayfield.org>
Date: Mon, 1 Jul 2024 21:18:33 +0200
Subject: [PATCH] draw path

---
 ocv_template_matching.py | 18 +++++++++++++++---
 util.py                  |  7 +++++++
 2 files changed, 22 insertions(+), 3 deletions(-)

diff --git a/ocv_template_matching.py b/ocv_template_matching.py
index e5145bc..cebc3b8 100644
--- a/ocv_template_matching.py
+++ b/ocv_template_matching.py
@@ -2,13 +2,13 @@ import cv2
 import sys
 import imutils as im
 
-from util import bbox_extend, bbox_round, image_crop, to_rect, bbox_add_position
+from util import bbox_extend, bbox_round, image_crop, to_rect, bbox_add_position, bbox_center
 
 COLOR_TRACKER = (0, 255, 0)
 COLOR_TRACKER_EXT = (0, 255, 255)
 COLOR_MATCHER = (0, 0, 255)
 COLOR_TEMPLATE = (255, 0, 0)
-IMG_SCALE_UP = 2
+IMG_SCALE_UP = 1
 TEMPLATE_MATCH_OVERLAP = 0
 
 video = cv2.VideoCapture("./data/IMG_1730.MP4")
@@ -28,13 +28,16 @@ if not ok:
 bb_crop = bbox_extend(cv2.selectROI("Image", image, False), TEMPLATE_MATCH_OVERLAP)
 crop = image_crop(image.copy(), bb_crop)
 
-bb_template = cv2.selectROI("Image", crop, False)
+bb_template = cv2.selectROI("Image", crop, fromCenter=True, showCrosshair=True)
 template = image_crop(crop.copy(), bb_template)
 
 # Initialize tracker with first frame and bounding box
 tracker = cv2.TrackerKCF().create()
 tracker.init(image, bb_crop)
 
+path = []
+line_from = None
+
 while True:
 	# Read a new frame
 	ok, image = video.read()
@@ -77,6 +80,15 @@ while True:
 		cv2.rectangle(image_anno, tracker_rect[0], tracker_rect[1], COLOR_TRACKER, 1)
 		matcher_crop = image_crop(image, matcher_bbox)
 
+		# Draw path
+		line_to = bbox_center(matcher_bbox)
+		if line_from is not None:
+			path.append({'from': line_from, 'to': line_to})
+		line_from = line_to
+
+		for p in path:
+			cv2.line(image_anno, p['from'], p['to'], (0, 0, 255), 2)
+
 		cv2.imshow("Crop", crop)
 		cv2.imshow("Image", image_anno)
 		cv2.imshow("Matcher res", res)
diff --git a/util.py b/util.py
index 9542319..dcbca45 100644
--- a/util.py
+++ b/util.py
@@ -28,6 +28,13 @@ def bbox_round(src):
 	return x, y, w, h
 
 
+def bbox_center(bbox):
+	x = round(bbox[0] + bbox[2]/2)
+	y = round(bbox[1] + bbox[3]/2)
+
+	return x, y
+
+
 def bbox_extend(bbox: cv2.typing.Rect, factor: float = 0):
 	we2 = bbox[2]*factor/2
 	he2 = bbox[3]*factor/2