#!/usr/bin/env python ''' Feature homography ================== Example of using features2d framework for interactive video homography matching. ORB features and FLANN matcher are used. The actual tracking is implemented by PlaneTracker class in plane_tracker.py Inspired by http://www.youtube.com/watch?v=-ZNYoL8rzPY video: http://www.youtube.com/watch?v=FirtmYcC0Vc Usage ----- feature_homography.py [<video source>] Keys: SPACE - pause video Select a textured planar object to track by drawing a box with a mouse. ''' import numpy as np import cv2 import video import common from common import getsize, draw_keypoints from plane_tracker import PlaneTracker class App: def __init__(self, src): self.cap = video.create_capture(src) self.frame = None self.paused = False self.tracker = PlaneTracker() cv2.namedWindow('plane') self.rect_sel = common.RectSelector('plane', self.on_rect) def on_rect(self, rect): self.tracker.clear() self.tracker.add_target(self.frame, rect) def run(self): while True: playing = not self.paused and not self.rect_sel.dragging if playing or self.frame is None: ret, frame = self.cap.read() if not ret: break self.frame = frame.copy() w, h = getsize(self.frame) vis = np.zeros((h, w*2, 3), np.uint8) vis[:h,:w] = self.frame if len(self.tracker.targets) > 0: target = self.tracker.targets[0] vis[:,w:] = target.image draw_keypoints(vis[:,w:], target.keypoints) x0, y0, x1, y1 = target.rect cv2.rectangle(vis, (x0+w, y0), (x1+w, y1), (0, 255, 0), 2) if playing: tracked = self.tracker.track(self.frame) if len(tracked) > 0: tracked = tracked[0] cv2.polylines(vis, [np.int32(tracked.quad)], True, (255, 255, 255), 2) for (x0, y0), (x1, y1) in zip(np.int32(tracked.p0), np.int32(tracked.p1)): cv2.line(vis, (x0+w, y0), (x1, y1), (0, 255, 0)) draw_keypoints(vis, self.tracker.frame_points) self.rect_sel.draw(vis) cv2.imshow('plane', vis) ch = cv2.waitKey(1) if ch == ord(' '): self.paused = not self.paused if ch == 27: break if __name__ == '__main__': print __doc__ import sys try: video_src = sys.argv[1] except: video_src = 0 App(video_src).run()