Web service (flask) gives "error: (-215:Assertion failed) !_src.empty() in function 'cvtColor'"

• face_recognition version: latest
• Python version: 3.6
• Operating System: Ubuntu

Description

I tried to make a simple project from your code where people upload an image and it compares to the encodings.pickle where it could recognize people faces. I’m using flask for the framework, xampp and postman to test the web service.

I already went all over the google, common issues example, your web_service_example.py and found related, but not similar, issues #599

What went wrong:

When I tried to run the code and tested it by uploading an image from postman, it returns an error

  File "...", line 56, in recog
    rgb = cv2.cvtColor(image, cv2.COLOR_BGR2RGB)
cv2.error: OpenCV(4.0.0-beta) /.../opencv/modules/imgproc/src/color.cpp:181: error: (-215:Assertion failed) !_src.empty() in function 'cvtColor'

Here’s the code

def recog(self, photo):
        data = pickle.loads(open("encodings.pickle", "rb").read())
        photo = str(photo)
        image = cv2.imread(photo)
        rgb = cv2.cvtColor(image, cv2.COLOR_BGR2RGB)

        boxes = face_recognition.face_locations(rgb, model="cnn")
        encodings = face_recognition.face_encodings(rgb, boxes)

        names = []

        for encoding in encodings:
            matches = face_recognition.compare_faces(data("encodings.pickle", "wb"), encoding)
            name = "Unknown"

            if True in matches:
                matchedIdxs = [i for (i, b) in enumerate(matches) if b]
                counts = {}
                for i in matchedIdxs:
                    name = data["names"][i]
                    counts[name] = counts.get(name, 0) + 1
                name = max(counts, key=counts.get)
            names.append(name)
        return name

Any help will be appreciated. I am completely clueless just like #599

Thank you for the support

[ageitgey]

That error message is basically a really complicated way of it complaining that the image you passed to cv2.cvtColor() was empty. So the problem is that earlier in your program cv2.imread() failed to load a valid image from the data that you passed in to it.

So either you didn’t read the data from the request correctly, you didn’t post the image data correctly with postman, or something with the image data is getting mangled along the way.

[Divya-14]

That error message is basically a really complicated way of it complaining that the image you passed to cv2.cvtColor() was empty. So the problem is that earlier in your program cv2.imread() failed to load a valid image from the data that you passed in to it.

So either you didn’t read the data from the request correctly, you didn’t post the image data correctly with postman, or something with the image data is getting mangled along the way.

@ageitgey , Thank you so much! I was struggling with that problem since 4 hours. Means a lot!