我正在尝试使用 OpenCV 读取卡并输出卡号和到期日期。
import cv2
import pytesseract
filename = 'image1.png'
img = cv2.imread(filename)
gray = cv2.cvtColor(img, cv2.COLOR_BGR2GRAY)
canny = cv2.Canny(gray, 50, 150, apertureSize=3)
result = pytesseract.image_to_string(canny)
print(f"OCR Results: {result}")
cv2.imshow('img', img)
cv2.imshow('canny', canny)
if cv2.waitKey(0) & 0xff == 27:
cv2.destroyAllWindows()
结果文本看起来不太好。请看下面的截图:
问题:如何正确处理卡片字体以获得更好的效果。任何想法都受到高度赞赏。
谢谢。
最佳答案
通过文本边缘时,OCR 似乎无法正常工作。
您最好应用阈值而不是使用 Canny。
我建议以下几个阶段:
S 中的所有灰色像素均为零,而彩色像素均高于零。
cv2.THRESH_OTSU
)。 因为您发布的图像包含一些背景。
这是代码:
import numpy as np
import cv2
import imutils # https://pypi.org/project/imutils/
import pytesseract
pytesseract.pytesseract.tesseract_cmd = r'C:\Program Files\Tesseract-OCR\tesseract.exe' # I am using Windows
img = cv2.imread('image1.png') # Read input image
# Convert from BGR to HSV color space
hsv = cv2.cvtColor(img, cv2.COLOR_BGR2HSV)
# Get the saturation color channel - all gray pixels are zero, and colored pixels are above zero.
s = hsv[:, :, 1]
# Convert to binary using automatic threshold (use cv2.THRESH_OTSU)
ret, thresh = cv2.threshold(s, 0, 255, cv2.THRESH_BINARY + cv2.THRESH_OTSU)
# Find contours (in inverted thresh)
cnts = cv2.findContours(thresh, cv2.RETR_EXTERNAL, cv2.CHAIN_APPROX_NONE)
cnts = imutils.grab_contours(cnts)
# Find the contour with the maximum area.
c = max(cnts, key=cv2.contourArea)
# Get bounding rectangle
x, y, w, h = cv2.boundingRect(c)
# Crop the bounding rectangle out of thresh
thresh_card = thresh[y:y+h, x:x+w].copy()
# OCR
result = pytesseract.image_to_string(thresh_card)
print(f"OCR Results:\n {result}")
# Show images for debugging
cv2.imshow('s', s)
cv2.imshow('thresh', thresh)
cv2.imshow('thresh_card', thresh_card)
cv2.waitKey(0)
cv2.destroyAllWindows()
OCR 结果:
Visa Classic
| By)
4000 1234 Sb18 9010
CARDHOLDER MARE
VISA
还是不完美……
年代:
脱粒:
阈值卡:
关于python - 如何在 Python 中使用 OpenCV 和 Tesseract 处理信用卡字体,我们在Stack Overflow上找到一个类似的问题: https://stackoverflow.com/questions/60811777/