1 import matplotlib.pyplot as plt 2 import matplotlib.image as mpimg 3 import numpy as np 4 5 # Read in the image 6 image = mpimg.imread('E:/spyder/a/a/test.jpg') 7 8 # Grab the x and y sizes and make two copies of the image 9 # With one copy we'll extract only the pixels that meet our selection, 10 # then we'll paint those pixels red in the original image to see our selection 11 # overlaid on the original. 12 ysize = image.shape[0] 13 xsize = image.shape[1] 14 color_select= np.copy(image) 15 line_image = np.copy(image) 16 17 # Define our color criteria 18 red_threshold = 200 19 green_threshold = 200 20 blue_threshold = 200 21 rgb_threshold = [red_threshold, green_threshold, blue_threshold] 22 23 # Define a triangle region of interest (Note: if you run this code, 24 # Keep in mind the origin (x=0, y=0) is in the upper left in image processing 25 # you'll find these are not sensible values!! 26 # But you'll get a chance to play with them soon in a quiz ;) 27 left_bottom = [0, 539] 28 right_bottom = [900, 500] 29 apex = [400, 300] 30 31 fit_left = np.polyfit((left_bottom[0], apex[0]), (left_bottom[1], apex[1]), 1) 32 fit_right = np.polyfit((right_bottom[0], apex[0]), (right_bottom[1], apex[1]), 1) 33 fit_bottom = np.polyfit((left_bottom[0], right_bottom[0]), (left_bottom[1], right_bottom[1]), 1) 34 35 # Mask pixels below the threshold 36 color_thresholds = (image[:,:,0] < rgb_threshold[0]) | 37 (image[:,:,1] < rgb_threshold[1]) | 38 (image[:,:,2] < rgb_threshold[2]) 39 40 # Find the region inside the lines 41 XX, YY = np.meshgrid(np.arange(0, xsize), np.arange(0, ysize)) 42 region_thresholds = (YY > (XX*fit_left[0] + fit_left[1])) & 43 (YY > (XX*fit_right[0] + fit_right[1])) & 44 (YY < (XX*fit_bottom[0] + fit_bottom[1])) 45 # Mask color selection 46 color_select[color_thresholds] = [0,0,0] 47 # Find where image is both colored right and in the region 48 line_image[~color_thresholds & region_thresholds] = [255,0,0] 49 50 # Display our two output images 51 plt.imshow(line_image)
结果如下图所示
代码27~29改动为
27 left_bottom = [0, 539] 28 right_bottom = [900, 539] 29 apex = [475, 320]
结果如下图
代码51改动为
51 x=[left_bottom[0],right_bottom[0],apex[0],left_bottom[0]] 52 y=[left_bottom[1],right_bottom[1],apex[1],left_bottom[1]]
53 plt.plot(x,y,'b--',lw=4)
54 plt.imshow(line_image)
结果如下图
