Is there a way to read an image from a url on openCV?-CodePudding

I am trying to read an image which is on a website, I am passing image link to cv2.imgread(https://website.com/photo.jpg) for example. But it returns a NoneType. The error says TypeError: cannot unpack non-iterable NoneType object

HERE's my code:

def get_isbn(x):
    print(x)
    
    image = cv2.imread(x)
    
    
    print(type(image))
    detectedBarcodes = decode(image)
    for barcode in detectedBarcodes:
        (x, y, w, h) = barcode.rect
        cv2.rectangle(image, (x, y), (x   w, y   h), (255, 0, 0), 5)

        # print(barcode.data)
        # print(type(barcode.data))
        byte_isbn = barcode.data
        string_isbn = str(byte_isbn, encoding='utf-8')
        
        return string_isbn

x is my url as a param.

CodePudding user response：

You need to convert link to array and then decode it with opencv.

function

import numpy as np
import urllib
import cv2
def url_to_image(url):
    resp = urllib.urlopen(url)
    image = np.asarray(bytearray(resp.read()), dtype="uint8")
    image = cv2.imdecode(image, cv2.IMREAD_COLOR)
    return image

Merge in your code

import numpy as np
import urllib
import cv2
def url_to_image(url):
    resp = urllib.urlopen(url)
    image = np.asarray(bytearray(resp.read()), dtype="uint8")
    image = cv2.imdecode(image, cv2.IMREAD_COLOR)
    return image
def get_isbn(x):
    print(x)

image = url_to_image(x)


print(type(image))
detectedBarcodes = decode(image)
for barcode in detectedBarcodes:
    (x, y, w, h) = barcode.rect
    cv2.rectangle(image, (x, y), (x   w, y   h), (255, 0, 0), 5)

    # print(barcode.data)
    # print(type(barcode.data))
    byte_isbn = barcode.data
    string_isbn = str(byte_isbn, encoding='utf-8')
    
    return string_isbn

CodePudding user response：

In some cases we can read the image as if it were a video composed of single frame.

It's not going to work in all cases, and it's not efficient in terms of execution time.
The advantage is that the solution uses only OpenCV package (it may also work in C for example).

Code sample:

import cv2

image_url = 'https://i.stack.imgur.com/fIDkn.jpg'

cap = cv2.VideoCapture(image_url)  # Open the URL as video

success, image = cap.read()  # Read the image as a video frame

if success:
    cv2.imshow('image ', image)  # Display the image for testing
    cv2.waitKey()

cap.release()
cv2.destroyAllWindows()