[python] OpenCV resize fails on large image with "error: (-215) ssize.area() > 0 in function cv::resize"

I'm using OpenCV 3.0.0 and Python 3.4.3 to process a very large RGB image (107162,79553,3). While I'm trying to resize it using the following code:

import cv2
image = cv2.resize(img, (0,0), fx=0.5, fy=0.5, interpolation=cv2.INTER_AREA)

I had this error message coming up :
"cv2.error: C:\opencv-3.0.0\source\modules\imgproc\src\imgwarp.cpp:3208: error: (-215) ssize.area() > 0 in function cv::resize"

I'm certain there is image content in the image array because I can save them into small tiles in jpg format. When I try to resize just a small part of the image, there is no problem and I end up with correctly resized image. (Taking a rather big chunk (50000,50000,3) still won't work, but it will work on a (10000,10000,3) chunk)

I'm wondering what could cause this problem and how I can solve this?

Thanks

I know this is a very old thread but I had the same problem which was due spaces in the images names.

e.g.

Image name: "hello o.jpg"

weirdly, by removing the spaces the function worked just fine.

Image name: "hello_o.jpg"

I had the same error. Resizing the images resolved the issue. However, I used online tools to resize the images because using pillow to resize them did not solve my problem.

For me the following work-around worked:

• split the array up into smaller sub arrays
• resize the sub arrays
• merge the sub arrays again

Here the code:

def split_up_resize(arr, res):
    """
    function which resizes large array (direct resize yields error (addedtypo))
    """

    # compute destination resolution for subarrays
    res_1 = (res[0], res[1]/2)
    res_2 = (res[0], res[1] - res[1]/2)

    # get sub-arrays
    arr_1 = arr[0 : len(arr)/2]
    arr_2 = arr[len(arr)/2 :]

    # resize sub arrays
    arr_1 = cv2.resize(arr_1, res_1, interpolation = cv2.INTER_LINEAR)
    arr_2 = cv2.resize(arr_2, res_2, interpolation = cv2.INTER_LINEAR)

    # init resized array
    arr = np.zeros((res[1], res[0]))

    # merge resized sub arrays
    arr[0 : len(arr)/2] = arr_1
    arr[len(arr)/2 :] = arr_2

    return arr

In my case I did a wrong modification in the image.

I was able to find the problem checking the image shape.

print img.shape

In my case,

image = cv2.imread(filepath)
final_img = cv2.resize(image, size_img)

filepath was incorrect, cv2.imshow didn't give any error in this case but due to wrong path cv2.resize was giving me error.

You can manually place a check in your code. Like this -

    if result != []:
        for face in result:
            bounding_box = face['box']
            x, y, w, h = bounding_box[0], bounding_box[1], bounding_box[2], bounding_box[3]
            rect_face = cv2.rectangle(frame, (x, y), (x+w, y+h), (46, 204, 113), 2)
            face = rgb[y:y+h, x:x+w]

            #CHECK FACE SIZE (EXIST OR NOT)
            if face.shape[0]*face.shape[1] > 0:

                predicted_name, class_probability = face_recognition(face)

                print("Result: ", predicted_name, class_probability)
`

This type of error also takes place because the resize is unable to get the image in simple the directory of the image may be wrong.In my case I left the forward slash during providing the location of file and this error took place after I put the slash problem was solved.

I was working with 3 files: The python script, the image, and the trained model.

Everything worked when I moved these 3 files into their own folder instead of in the directory with the other python scripts.

Turns out for me this error was actually telling the truth - I was trying to resize a Null image, which was usually the 'last' frame of a video file, so the assertion was valid.

Now I have an extra step before attempting the resize operation, which is to do the assertion myself:

def getSizedFrame(width, height):
"""Function to return an image with the size I want"""    
    s, img = self.cam.read()

    # Only process valid image frames
    if s:
            img = cv2.resize(img, (width, height), interpolation = cv2.INTER_AREA)
    return s, img

Now I don't see the error.

Also pay attention to the object type of your numpy array, converting it using .astype('uint8') resolved the issue for me.

Turns out I had a .csv file at the end of the folder from which I was reading all the images. Once I deleted that it worked alright

Make sure that it's all images and that you don't have any other type of file

I am having OpenCV version 3.4.3 on MacOS. I was getting the same error as above.

I changed my code from

frame = cv2.resize(frame, (0,0), fx=0.5, fy=0.5)   

to

frame = cv2.resize(frame, None, fx=0.5, fy=0.5)    

Now its working fine for me.