Initial commit with project files

2_Bildbearbeitung/ü10/l_b.py

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+import cv2
+import numpy as np
+
+img = cv2.imread("../../data/car.png", cv2.IMREAD_GRAYSCALE)
+img = cv2.resize(img, (500, 500))
+# Do some preprocessing
+img = img.astype(float)
+img = 50 + (105 * img / 255)
+cv2.imshow("Original", img.astype(np.uint8))
+
+# Implement CLAHE
+new_image = np.zeros_like(img)
+height, width = img.shape
+for x in range(width):
+    for y in range(height):
+        x1, x2 = np.maximum(0, x - 25), np.minimum(x + 25, height)
+        y1, y2 = np.maximum(0, y - 25), np.minimum(y + 25, height)
+        hist, values = np.histogram(img[y1:y2, x1:x2], bins=256, range=(0, 256))
+        clip_limit = 0.6 * round(np.max(hist))
+        higher_values = hist >= clip_limit
+        sum_of_higher_values = np.sum(hist[higher_values] - clip_limit)
+        hist = np.minimum(hist, clip_limit)
+        hist = hist + round(sum_of_higher_values / 256)
+        cum_hist = np.cumsum(hist)
+        v = round(img[y, x])
+        new_image[y, x] = 255 * cum_hist[v] / cum_hist[255]
+
+cv2.imshow("CLAHE", new_image.astype(np.uint8))
+
+cv2.waitKey(0)
+