Getting error - 'PngImageFile' object has no attribute 'shape' on transferring video frames from client to flask server using Socketio

Question

My application is to switch on cam on the client-side, take the frame, perform the ML process on it in the backend and throw it back to the client.

This part of the code (in bold) is throwing error - PngImageFile' object has no attribute 'shape'.

This code line has a problem - frame = imutils.resize(pimg, width=700)

I guess some processing is not in the right format. Please guide

@socketio.on('image')
def image(data_image):
    sbuf = io.StringIO()
    sbuf.write(data_image)

    # decode and convert into image
    b = io.BytesIO(base64.b64decode(data_image))
    pimg = Image.open(b)

    # Process the image frame
    frame = imutils.resize(**pimg,** width=700)
    frame = cv2.flip(frame, 1)
    imgencode = cv2.imencode('.jpg', frame)[1]

    # base64 encode
    stringData = base64.b64encode(imgencode).decode('utf-8')
    b64_src = 'data:image/jpg;base64,'
    stringData = b64_src + stringData

    # emit the frame back
    emit('response_back', stringData)

score 5 · Accepted Answer · answered Jun 14 '20 at 07:24

5

The problem is that pimg is in PIL image format. While imutils.resize function expects the image in Numpy array format. So, after pimg = Image.open(b) line you need to convert the PIL image to Numpy array like below:

pimg = np.array(pimg)

For this you have to import numpy library like below:

import numpy as np

answered Jun 14 '20 at 07:24

amras

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Hey cool, this part is solved. there is another problem though, on the frontend, I am receiving only black frames. – Kumar Jun 14 '20 at 07:43
Good to know it solved your this particular issue. You may consider to accept the answer as far as this specific issue is concerned. For the other issue you can raise another question with more details so that it can be addressed. – amras Jun 14 '20 at 07:50

score 0 · Answer 2 · answered Mar 30 '21 at 17:58

Try this out. This helped for a similar problem for me.

img_arr = np.array(img.convert("RGB"))

The problem was in the mode of the image. I had to convert it from 'P' to 'RGB'.

print(img)
>> <PIL.PngImagePlugin.PngImageFile image mode=P size=500x281 at 0x7FE836909C10>

Getting error - 'PngImageFile' object has no attribute 'shape' on transferring video frames from client to flask server using Socketio

2 Answers2