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POHow can i know if there are white pixels in a binary image in some coordinates (stored in a list) in python?
 

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  1. POHow can i know if there are white pixels in a binary image in some coordinates (stored in a list) in python?
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    <p>I have a <a href="http://i.imgur.com/grnpDpP.jpg" rel="nofollow">numpy array binary</a> (black and white) image and coordinates in a list of tuples like:</p> <pre><code>coordlist =[(110, 110), (110, 111), (110, 112), (110, 113), (110, 114), (110, 115), (110, 116), (110, 117), (110, 118), (110, 119), (110, 120), (100, 110), (101, 111), (102, 112), (103, 113), (104, 114), (105, 115), (106, 116), (107, 117), (108, 118), (109, 119), (110, 120)] </code></pre> <p>or as:</p> <pre><code>coordx = [110, 110, 110, 110, 110, 110, 110, 110, 110, 110, 110, 100, 101, 102, 103, 104, 105, 106, 107, 108, 109, 110] coordy = [110, 111, 112, 113, 114, 115, 116, 117, 118, 119, 120, 110, 111, 112, 113, 114, 115, 116, 117, 118, 119, 120] </code></pre> <p>How can i check if there is a "white" pixel in the image with that coordinates list? I also would like check the white pixels that are around 3 pixels range far from that coordinates list.</p> <p>i.e.:</p> <pre><code>for i, j in coordx, coordy: for k in a range (k-3, k + 3) for l in a range (l-3, l + 3) #checking white pixels also for pixel near coordinates list </code></pre> <p>I thought about "where" function.</p> <pre><code>from skimage import morphology import numpy as np path = 'image/a.jpg' col = mh.imread(path) bn0 = col[:,:,0] bn = (bn0 &lt; 127) bnsk = morphology.skeletonize(bn) bnskInt = np.array(bnsk, dtype=np.uint8) #finding if there are white pixel in the coord list and around that in a 5 pixel range for i in coordlist: np.where(?) </code></pre> <p><strong>UPDATE</strong>.</p> <p>I tried to use shape (128, 128) instead of (128, 128, 3) because my image have this shape: (a,b) but now it does not find the white pixels! Why in this way does it find anything?</p> <pre><code> white_pixel = np.array([255, 255]) img = np.random.randint(0, 256, (128, 128)) print(img[150]) print(img.shape) img[110, 110] = 255 img[109, 110] = 255 mask = np.zeros((128, 128), dtype=bool) mask[coordx, coordy] = 1 #structure = np.ones((3, 3, 1)) #mask = scipy.ndimage.morphology.binary_dilation(mask, structure) is_white = np.all((img * mask) == white_pixel, axis=-1) # This will tell you which pixels are white print np.where(is_white) # This will tell you if any pixels are white print np.any(is_white) </code></pre> <p>output:</p> <pre><code>(array([], dtype=int32),) False </code></pre>
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      1. POHow can i know if there are white pixels in a binary image in some coordinates (stored in a list) in python?
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      1. POHow can i know if there are white pixels in a binary image in some coordinates (stored in a list) in python?
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