ndarray图片数据与base64字符串之间相互转换

东方耀

ndarray图片数据与base64字符串之间相互转换

1. 
   
2. import cv2
   
3. import base64
   
4. import numpy as np
   
5. 
   
6. img_path = "./testfiles/face.jpg"
   
7. img = cv2.imread(img_path)
   
8. print(type(img), img.shape)
   
9. ori_h, ori_w, c = img.shape
   
10. 
    
11. # ndarray图片数据转base64编码
    
12. pic_str = base64.b64encode(img)
    
13. print(type(pic_str))
    
14. # <class 'bytes'>变成字符串str类型
    
15. pic_str = pic_str.decode()
    
16. print(type(pic_str))
    
17. 
    
18. cv2.imshow("ori", img)
    
19. cv2.waitKey(0)
    
20. 
    
21. # base64解码 转成ndarray类型
    
22. img_data = base64.b64decode(pic_str)
    
23. nparr = np.fromstring(img_data, np.uint8)
    
24. print(type(nparr), nparr.shape, nparr.dtype)
    
25. nparr = nparr.reshape((ori_h, ori_w, c))
    
26. print(type(nparr), nparr.shape, nparr.dtype)
    
27. # img_np = cv2.imdecode(nparr, cv2.IMREAD_COLOR)
    
28. cv2.imshow("ori_64", nparr)
    
29. cv2.waitKey(0)
    
30. 
    

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base64编码  对字符串的  而不是图像数据本身

1. # -*- coding: utf-8 -*-
   
2. __author__ = u'东方耀 微信：dfy_88888'
   
3. __date__ = '2020/5/12 下午2:55'
   
4. __product__ = 'PyCharm'
   
5. __filename__ = 'dfy_demo03'
   
6. 
   
7. 
   
8. import cv2
   
9. import base64
   
10. import numpy as np
    
11. 
    
12. img_path = "./testfiles/face.jpg"
    
13. img = cv2.imread(img_path)
    
14. print(type(img), img.shape)
    
15. # 将图片编码成流数据，放到内存缓存中，然后转化成string格式
    
16. img_str = cv2.imencode('.png', img)[1].tostring()
    
17. 
    
18. 
    
19. # base64编码  对字符串的  而不是图像数据本身
    
20. pic_str = base64.b64encode(img_str)
    
21. print(type(pic_str))
    
22. # <class 'bytes'>变成字符串str类型
    
23. pic_str = pic_str.decode()
    
24. print(type(pic_str))
    
25. print("字符串的长度：", len(pic_str))
    
26. 
    
27. cv2.imshow("ori", img)
    
28. cv2.waitKey(0)
    
29. 
    
30. # base64解码 转成ndarray类型
    
31. img_data = base64.b64decode(pic_str)
    
32. nparr = np.fromstring(img_data, np.uint8)
    
33. print(type(nparr), nparr.shape, nparr.dtype)
    
34. img_restore = cv2.imdecode(nparr, cv2.IMREAD_COLOR)
    
35. print(type(img_restore), img_restore.shape, img_restore.dtype)
    
36. cv2.imshow("img_restore", img_restore)
    
37. cv2.waitKey(0)
    
38. 
    
39. 
    

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# 用于HTTP传输的时候通常会用
# base64.urlsafe_b64encode代替base64.b64encode，
# base64.urlsafe_b64decode代替base64.b64decode
#
# 两者的区别在于base64.urlsafe_b64encode会把+用-代替，/用_代替，避免URL把+``/当成特殊字符解析了

1. # -*- coding: utf-8 -*-
   
2. __author__ = u'东方耀 微信：dfy_88888'
   
3. __date__ = '2020/5/12 下午2:55'
   
4. __product__ = 'PyCharm'
   
5. __filename__ = 'dfy_demo03'
   
6. 
   
7. 
   
8. import cv2
   
9. import base64
   
10. import numpy as np
    
11. 
    
12. img_path = "./testfiles/face.jpg"
    
13. img = cv2.imread(img_path)
    
14. print(type(img), img.shape)
    
15. # 将图片编码成流数据，放到内存缓存中，然后转化成string格式
    
16. img_str = cv2.imencode('.png', img)[1].tostring()
    
17. 
    
18. 
    
19. # base64编码  对字符串的  而不是图像数据本身
    
20. # pic_str = base64.b64encode(img_str)
    
21. pic_str = base64.urlsafe_b64encode(img_str)
    
22. print(type(pic_str))
    
23. # <class 'bytes'>变成字符串str类型
    
24. pic_str = pic_str.decode()
    
25. print(type(pic_str))
    
26. print("字符串的长度：", len(pic_str))
    
27. 
    
28. cv2.imshow("ori", img)
    
29. cv2.waitKey(0)
    
30. 
    
31. # base64解码 转成ndarray类型
    
32. # img_data = base64.b64decode(pic_str)
    
33. img_data = base64.urlsafe_b64decode(pic_str)
    
34. nparr = np.fromstring(img_data, np.uint8)
    
35. print(type(nparr), nparr.shape, nparr.dtype)
    
36. img_restore = cv2.imdecode(nparr, cv2.IMREAD_COLOR)
    
37. print(type(img_restore), img_restore.shape, img_restore.dtype)
    
38. cv2.imshow("img_restore", img_restore)
    
39. cv2.waitKey(0)
    
40. 
    
41. 
    
42. 
    
43. 
    

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