diff --git a/scan.py b/scan.py new file mode 100644 index 0000000..a58ff11 --- /dev/null +++ b/scan.py @@ -0,0 +1,163 @@ +# 导入工具包 +import numpy as np +import argparse +import cv2 +import pytesseract +import os +from PIL import Image + +# 设置参数 +ap = argparse.ArgumentParser() +ap.add_argument("-i", "--image", required = True, + help = "Path to the image to be scanned") +args = vars(ap.parse_args()) + +def order_points(pts): + # 一共4个坐标点 + rect = np.zeros((4, 2), dtype = "float32") + + # 按顺序找到对应坐标0123分别是 左上,右上,右下,左下 + # 计算左上,右下 + s = pts.sum(axis = 1) + rect[0] = pts[np.argmin(s)] + rect[2] = pts[np.argmax(s)] + + # 计算右上和左下 + diff = np.diff(pts, axis = 1) + rect[1] = pts[np.argmin(diff)] + rect[3] = pts[np.argmax(diff)] + + return rect + +def four_point_transform(image, pts): + # 获取输入坐标点 + rect = order_points(pts) + (tl, tr, br, bl) = rect + + # 计算输入的w和h值 + widthA = np.sqrt(((br[0] - bl[0]) ** 2) + ((br[1] - bl[1]) ** 2)) + widthB = np.sqrt(((tr[0] - tl[0]) ** 2) + ((tr[1] - tl[1]) ** 2)) + maxWidth = max(int(widthA), int(widthB)) + + heightA = np.sqrt(((tr[0] - br[0]) ** 2) + ((tr[1] - br[1]) ** 2)) + heightB = np.sqrt(((tl[0] - bl[0]) ** 2) + ((tl[1] - bl[1]) ** 2)) + maxHeight = max(int(heightA), int(heightB)) + + # 变换后对应坐标位置 + dst = np.array([ + [0, 0], + [maxWidth - 1, 0], + [maxWidth - 1, maxHeight - 1], + [0, maxHeight - 1]], dtype = "float32") + + # 计算变换矩阵 + M = cv2.getPerspectiveTransform(rect, dst) + warped = cv2.warpPerspective(image, M, (maxWidth, maxHeight)) + + # 返回变换后结果 + return warped + +def resize(image, width=None, height=None, inter=cv2.INTER_AREA): + dim = None + (h, w) = image.shape[:2] + if width is None and height is None: + return image + if width is None: + r = height / float(h) + dim = (int(w * r), height) + else: + r = width / float(w) + dim = (width, int(h * r)) + resized = cv2.resize(image, dim, interpolation=inter) + return resized + +# 读取输入 +image = cv2.imread(args["image"]) +#坐标也会相同变化 +ratio = image.shape[0] / 500.0 +orig = image.copy() + + +image = resize(orig, height = 500) + +# 预处理 +gray = cv2.cvtColor(image, cv2.COLOR_BGR2GRAY) +gray = cv2.GaussianBlur(gray, (5, 5), 0) +edged = cv2.Canny(gray, 75, 200) + +# 展示预处理结果 +print("STEP 1: 边缘检测") +cv2.imshow("Image", image) +cv2.imshow("Edged", edged) +cv2.waitKey(0) +cv2.destroyAllWindows() + +# 轮廓检测 +cnts = cv2.findContours(edged.copy(), cv2.RETR_LIST, cv2.CHAIN_APPROX_SIMPLE)[0] +cnts = sorted(cnts, key = cv2.contourArea, reverse = True)[:5] + +# 遍历轮廓 +for c in cnts: + # 计算轮廓近似 + peri = cv2.arcLength(c, True) + # C表示输入的点集 + # epsilon表示从原始轮廓到近似轮廓的最大距离,它是一个准确度参数 + # True表示封闭的 + approx = cv2.approxPolyDP(c, 0.05 * peri, True) + + # 4个点的时候就拿出来 + if len(approx) == 4: + screenCnt = approx + break + +# 展示结果 +print("STEP 2: 获取轮廓") +cv2.drawContours(image, [screenCnt], -1, (0, 255, 0), 2) +cv2.imshow("Outline", image) +cv2.waitKey(0) +cv2.destroyAllWindows() + +# 透视变换 +warped = four_point_transform(orig, screenCnt.reshape(4, 2) * ratio) + +# 二值处理 +warped = cv2.cvtColor(warped, cv2.COLOR_BGR2GRAY) +ref = cv2.threshold(warped, 100, 255, cv2.THRESH_BINARY)[1] +cv2.imwrite('scan.jpg', ref) +# 展示结果 +print("STEP 3: 变换") +cv2.imshow("Original", resize(orig, height = 650)) +cv2.imshow("Scanned", resize(ref, height = 650)) +cv2.waitKey(0) +cv2.destroyAllWindows() + +''' +OCR扫描 +''' +preprocess = "blur" + +if preprocess == "thresh": + gray = cv2.threshold(ref, 0, 255, cv2.THRESH_BINARY | cv2.THRESH_OTSU)[1] +if preprocess == "blur": + gray = cv2.medianBlur(ref, 3) +cv2.imshow("Detect", gray) + +filename = "{}.png".format(os.getpid()) +cv2.imwrite(filename, gray) +text = pytesseract.image_to_string(Image.open(filename)) +os.remove(filename) + +encodings = ['utf-8', 'latin1', 'iso-8859-1', 'cp1252', 'gbk', 'big5'] +for encoding in encodings: + try: + with open("out.txt", 'w', encoding=encoding, errors="replace") as file: + file.write(text) + break + except UnicodeDecodeError: + continue +file.close() +print("text is written to out.txt") + +# Wait for pressing any key +cv2.waitKey(0) +cv2.destroyAllWindows() \ No newline at end of file