adding modul for image rotation after rollback because of a gitpull fail

scripts/deskew_demo.py

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+#sample usage: python3 scripts/deskew_demo.py /path/to/crooked.pdf 0
+import argparse
+import numpy as np
+import pdf2image
+
+from vidocp.utils.display import show_mpl
+from vidocp.utils.deskew import deskew_image
+
+
+def parse_args():
+    parser = argparse.ArgumentParser()
+    parser.add_argument("pdf_path")
+    parser.add_argument("page_index", type=int)
+    
+    args = parser.parse_args()
+
+    return args
+
+
+if __name__ == "__main__":
+    args = parse_args()
+    page = pdf2image.convert_from_path(args.pdf_path, first_page=args.page_index + 1, last_page=args.page_index + 1)[0]
+    page = np.array(page)
+
+    show_mpl(page)
+    page = deskew_image(page, verbose=True)
+    show_mpl(page)

vidocp/utils/deskew.py

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+import numpy as np
+import cv2
+
+
+def detect_angle(im: np.array, max_skew_deg=10, min_nlines=5) -> int:
+    max_skew_rad = np.deg2rad(max_skew_deg)
+    width = im.shape[1]
+
+    im_gs = cv2.cvtColor(im, cv2.COLOR_BGR2GRAY)
+    im_gs = cv2.fastNlMeansDenoising(im_gs, h=3)
+    im_bw = cv2.threshold(im_gs, 0, 255, cv2.THRESH_BINARY_INV | cv2.THRESH_OTSU)[1]
+
+    lines = cv2.HoughLinesP(
+        im_bw, 1, np.pi / 180, 200, minLineLength=width / 12, maxLineGap=width / 150
+    )
+
+    angles = []
+    for line in lines:
+        x1, y1, x2, y2 = line[0]
+        angles.append(np.arctan2(y2 - y1, x2 - x1))
+    angles = [angle for angle in angles if abs(angle) < max_skew_rad]
+
+    if len(angles) < min_nlines:
+        return 0
+
+    return np.rad2deg(np.median(angles))
+
+
+def rotate_straight(im: np.array, skew_angle: int) -> np.array:
+    h, w = im.shape[:2]
+    center = (w // 2, h // 2)
+    
+    M = cv2.getRotationMatrix2D(center, skew_angle, 1.0)
+    
+    rotated = cv2.warpAffine(
+        im, M, (w, h), flags=cv2.INTER_CUBIC, borderMode=cv2.BORDER_REPLICATE
+    )
+    
+    return rotated
+
+
+def deskew_image(image: np.array, verbose=False) -> np.array:
+    skew_angle = detect_angle(image)
+    if verbose:
+        print(f"Skew angle: {skew_angle}")
+    deskewed = rotate_straight(image, skew_angle)
+    return deskewed
+