从二进制图像OpenCV C ++中裁剪文本 [英] Crop text out of binary image OpenCV C++

问题描述

如何裁剪图像，以便使用OpenCV在图像中仅包含文本？

How can I crop the image so that only the text is included in the image using OpenCV?

推荐答案

方法

1. 在垂直和水平方向上扩展图像


2. 查找边界矩形


3. 裁剪图像

---

代码

# reading the input image in grayscale image
image = cv2.imread('image2.png',cv2.IMREAD_GRAYSCALE)
image /= 255
if image is None:
    print 'Can not find/read the image data'
# Defining ver and hor kernel
N = 5
kernel = np.zeros((N,N), dtype=np.uint8)
kernel[2,:] = 1
dilated_image = cv2.dilate(image, kernel, iterations=2)

kernel = np.zeros((N,N), dtype=np.uint8)
kernel[:,2] = 1
dilated_image = cv2.dilate(dilated_image, kernel, iterations=2)
image *= 255

# finding contours in the dilated image
contours,a = cv2.findContours(dilated_image,cv2.RETR_TREE, cv2.CHAIN_APPROX_SIMPLE)

# finding bounding rectangle using contours data points
rect = cv2.boundingRect(contours[0])
pt1 = (rect[0],rect[1])
pt2 = (rect[0]+rect[2],rect[1]+rect[3])
cv2.rectangle(image,pt1,pt2,(100,100,100),thickness=2)

# extracting the rectangle
text = image[rect[1]:rect[1]+rect[3],rect[0]:rect[0]+rect[2]]

plt.subplot(1,2,1), plt.imshow(image,'gray')
plt.subplot(1,2,2), plt.imshow(text,'gray')

plt.show()

---

输出

这篇关于从二进制图像OpenCV C ++中裁剪文本的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！