ComponentDevelopment/OCRPython/backup/ocr.py

152 lines
4.8 KiB
Python

# -*- coding: UTF-8 -*-
import cv2
import matplotlib.pyplot as plt
import numpy as np
import pytesseract
from PIL import Image
debug = 1
def preprocess(gray):
ret, binary = cv2.threshold(gray, 180, 255, cv2.THRESH_BINARY_INV)
ele = cv2.getStructuringElement(cv2.MORPH_RECT, (15, 10))
dilation = cv2.dilate(binary, ele, iterations=1)
cv2.imwrite("binary.png", binary)
cv2.imwrite("dilation.png", dilation)
return dilation
def findTextRegion(img):
region = []
# 1. 查找轮廓
#image, contours, hierarchy = cv2.findContours(img, cv2.RETR_TREE, cv2.CHAIN_APPROX_SIMPLE)
contours, hierarchy = cv2.findContours(img, cv2.RETR_TREE, cv2.CHAIN_APPROX_SIMPLE)
# 2. 筛选那些面积小的
for i in range(len(contours)):
cnt = contours[i]
# 计算该轮廓的面积
area = cv2.contourArea(cnt)
# 面积小的都筛选掉
if (area < 300):
continue
# 轮廓近似,作用很小
epsilon = 0.001 * cv2.arcLength(cnt, True)
approx = cv2.approxPolyDP(cnt, epsilon, True)
# 找到最小的矩形,该矩形可能有方向
rect = cv2.minAreaRect(cnt)
if debug:
print("rect is: ", rect)
# box是四个点的坐标
box = cv2.boxPoints(rect)
box = np.int0(box)
# 计算高和宽
height = abs(box[0][1] - box[2][1])
width = abs(box[0][0] - box[2][0])
# 筛选那些太细的矩形,留下扁的
if (height > width * 1.2):
continue
# 太扁的也不要
if (height * 18 < width):
continue
if (width > img.shape[1] / 2 and height > img.shape[0] / 20):
region.append(box)
return region
def grayImg(img):
# 转化为灰度图
gray = cv2.resize(img, (img.shape[1] * 3, img.shape[0] * 3), interpolation=cv2.INTER_CUBIC)
gray = cv2.cvtColor(gray, cv2.COLOR_BGR2GRAY)
retval, gray = cv2.threshold(gray, 120, 255, cv2.THRESH_OTSU + cv2.THRESH_BINARY)
return gray
def detect(img):
# fastNlMeansDenoisingColored(InputArray src, OutputArray dst, float h=3, float hColor=3, int templateWindowSize=7, int searchWindowSize=21 )
gray = cv2.fastNlMeansDenoisingColored(img, None, 10, 3, 3, 3)
coefficients = [0, 1, 1]
m = np.array(coefficients).reshape((1, 3))
gray = cv2.transform(gray, m)
if debug:
cv2.imwrite("gray.png", gray)
# 2. 形态学变换的预处理,得到可以查找矩形的图片
dilation = preprocess(gray)
# 3. 查找和筛选文字区域
region = findTextRegion(dilation)
# 4. 用绿线画出这些找到的轮廓
ii = 0
for box in region:
h = abs(box[0][1] - box[2][1])
w = abs(box[0][0] - box[2][0])
Xs = [i[0] for i in box]
Ys = [i[1] for i in box]
x1 = min(Xs)
y1 = min(Ys)
cv2.drawContours(img, [box], 0, (0, 255, 0), 2)
if w > 0 and h > 0 and x1 < gray.shape[1] / 2:
idImg = grayImg(img[y1:y1 + h, x1:x1 + w])
cv2.imwrite(str(ii) + ".png", idImg)
break
ii += 1
if debug:
# 带轮廓的图片
cv2.imwrite("contours.png", img)
return idImg
def crop_image(img, tol=0):
mask = img < tol
return img[np.ix_(mask.any(1), mask.any(0))]
def ocrIdCard(imgPath, realId=""):
import os
# 获取 TESSDATA_PREFIX 环境变量的值
tessdata_prefix = os.environ.get('TESSDATA_PREFIX')
# 打印出 TESSDATA_PREFIX 环境变量的值
print("TESSDATA_PREFIX:", tessdata_prefix)
img = cv2.imread(imgPath, cv2.IMREAD_COLOR)
img = cv2.resize(img, (428, 270), interpolation=cv2.INTER_CUBIC)
idImg = detect(img)
image = Image.fromarray(idImg)
#tessdata_dir_config = '-c tessedit_char_whitelist=0123456789X --tessdata-dir "./"'
print("checking")
print(realId)
result = pytesseract.image_to_string(img, lang='chi_sim' )
#result = pytesseract.image_to_string(image, lang='chi_sim' )#ocrb,config=tessdata_dir_config,chi_sim
print(result)
# print(pytesseract.image_to_string(image, lang='eng', config=tessdata_dir_config))
if debug:
f, axarr = plt.subplots(2, 3)
axarr[0, 0].imshow(cv2.imread(imgPath))
axarr[0, 1].imshow(cv2.imread("gray.png"))
axarr[0, 2].imshow(cv2.imread("binary.png"))
axarr[1, 0].imshow(cv2.imread("dilation.png"))
axarr[1, 1].imshow(cv2.imread("contours.png"))
axarr[1, 2].set_title("exp:" + realId + "\nocr:" + result)
axarr[1, 2].imshow(cv2.imread("0.png"))
plt.show()
ocrIdCard("/Users/wangvivi/Desktop/Code/ocrtest/images/id_card.JPG", "11204416541220243X")
# ocrIdCard("test2.png", "430523197603204314")
# ocrIdCard("test3.png", "37030519820727311X")
# ocrIdCard("test4.png", "431023199205297212")
# ocrIdCard("test0.png", "445281198606095334")