Open Source Computer Vision Library
https://opencv.org/
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38 lines
1.0 KiB
38 lines
1.0 KiB
import numpy as np |
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import cv2, cv |
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import video |
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import sys |
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try: fn = sys.argv[1] |
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except: fn = video.presets['chess'] |
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cam = video.create_capture(fn) |
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ret, prev = cam.read() |
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#prev = cv2.pyrDown(prev) |
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prevgray = cv2.cvtColor(prev, cv.CV_BGR2GRAY) |
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def draw_flow(img, flow, step): |
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h, w = img.shape[:2] |
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y, x = map(np.ravel, np.mgrid[step/2:h:step, step/2:w:step]) |
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f = flow[y,x] |
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x1 = x + f[:,0] |
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y1 = y + f[:,1] |
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#lines = np.int32( np.vstack([x, y, x1, y1]).T ) |
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vis = cv2.cvtColor(img, cv.CV_GRAY2BGR) |
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#print lines |
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#cv2.polylines(vis, lines, 0, (0, 255, 0)) |
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for x_, y_, x1_, y1_ in np.int32(zip(x, y, x1, y1)): |
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cv2.line(vis, (x_, y_), (x1_, y1_), (0, 255, 0)) |
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return vis |
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while True: |
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ret, img = cam.read() |
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#img = cv2.pyrDown(img) |
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gray = cv2.cvtColor(img, cv.CV_BGR2GRAY) |
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flow = cv2.calcOpticalFlowFarneback(prevgray, gray, 0.5, 3, 15, 3, 5, 1.2, 0) |
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prevgray = gray |
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cv2.imshow('flow', draw_flow(gray, flow, 16)) |
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if cv2.waitKey(5) == 27: |
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break |
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