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@chuanenlin
Created April 12, 2019 02:29
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import cv2 as cv
import numpy as np
# Parameters for Shi-Tomasi corner detection
# feature_params = dict(maxCorners = 300, qualityLevel = 0.2, minDistance = 2, blockSize = 7)
# Parameters for Lucas-Kanade optical flow
# lk_params = dict(winSize = (15,15), maxLevel = 2, criteria = (cv.TERM_CRITERIA_EPS | cv.TERM_CRITERIA_COUNT, 10, 0.03))
# The video feed is read in as a VideoCapture object
# cap = cv.VideoCapture("shibuya.mp4")
# Variable for color to draw optical flow track
# color = (0, 255, 0)
# ret = a boolean return value from getting the frame, first_frame = the first frame in the entire video sequence
# ret, first_frame = cap.read()
# Converts frame to grayscale because we only need the luminance channel for detecting edges - less computationally expensive
prev_gray = cv.cvtColor(first_frame, cv.COLOR_BGR2GRAY)
# while(cap.isOpened()):
# ret = a boolean return value from getting the frame, frame = the current frame being projected in the video
# ret, frame = cap.read()
# Converts each frame to grayscale - we previously only converted the first frame to grayscale
gray = cv.cvtColor(frame, cv.COLOR_BGR2GRAY)
# Visualizes checkpoint 2
cv.imshow("grayscale", gray)
# Updates previous frame
prev_gray = gray.copy()
# Frames are read by intervals of 10 milliseconds. The programs breaks out of the while loop when the user presses the 'q' key
# if cv.waitKey(10) & 0xFF == ord('q'):
# break
# The following frees up resources and closes all windows
# cap.release()
# cv.destroyAllWindows()
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