cv2 imdecode returns none with base64 string - linux

Question

When i try to convert base64 string into image i am getting none in CV2.
Following is my code
import cv2
import numpy as np
def bsae62toimage(imgvalue):
imge = "R0lGODlhEAAQAMQAAORHHOVSKudfOulrSOp3WOyDZu6QdvCchPGolfO0o/XBs/fNwfjZ0frl3/zy7////wAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAACH5BAkAABAALAAAAAAQABAAAAVVICSOZGlCQAosJ6mu7fiyZeKqNKToQGDsM8hBADgUXoGAiqhSvp5QAnQKGIgUhwFUYLCVDFCrKUE1lBavAViFIDlTImbKC5Gm2hB0SlBCBMQiB0UjIQA7"
nparr = np.fromstring(imge,np.uint8)
print(nparr.shape)
img1 = cv2.imdecode(nparr,cv2.IMREAD_UNCHANGED)
print(img1.shape)
It is printing the numpy array but cv2.imdecode is returning None. Can you help me to find the problem in my code?
My Findings: np.fromstring it returns 1D array. I assume it should it should return 3D array. But i may be wrong.

Answer 1

Since it is unclear as from where have you obtained the imge = "R0lGODlhEA..." variable. I would present an ideal flow for converting OpenCV image to base64 string and converting it back to OpenCV img as:
import cv2
import base64
import numpy as np
def to_base64(img):
_, buf = cv2.imencode(".png", img)
return base64.b64encode(buf)
def from_base64(buf):
buf_decode = base64.b64decode(buf)
buf_arr = np.fromstring(buf_decode, dtype=np.uint8)
return cv2.imdecode(buf_arr, cv2.IMREAD_UNCHANGED)
img = cv2.imread("/path/to/img.png")
img_base64 = to_base64(img)
img_decoded = from_base64(img_base64)
print img_decoded.shape
Also the documentation states that:
If the buffer is too short or contains invalid data, the empty
matrix/image is returned.
It seems to me that imge = "R0lGODlhEA..." is invalid.