I don't know why cv2.rectangle causes errors

[leejoohi]

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`from _testinternalcapi import get_config
from django.shortcuts import render
from django.http import StreamingHttpResponse
import yolov8

import cv2
from collections import Counter

from PIL import Image as im
from ultralytics import YOLO
from ultralytics.yolo.utils.plotting import Annotator
from ultralytics.yolo.utils.torch_utils import select_device

Create your views here.

def index(request):
return render(request, 'index.html')

model = YOLO('best.pt')

def stream():
cap = cv2.VideoCapture(0)
while True:
ret, frame = cap.read()
if not ret:
print("Error: failed to capture image")
break

    results = model(frame, augment=True)
    cv2.imwrite('demo.jpg', frame)

    colors = ['brown', 'green', 'orange', 'purple', 'red', 'yellow']
    cs = ['brown', 'green', 'orange', 'purple', 'red', 'yellow']
    cal = []
    try:
        tensor_list = results[0].boxes.data
        detection = tensor_list.tolist()
        total_product_count = len(detection)
        if len(detection) == 0:
            print("Detected 0 Products")
            return "Unknow", "Found 0"
        else:
            for det in detection:
                x, y, w, h = int(det[0]), int(det[1]), int(det[2]), int(det[3])
                confidence = det[4]
                cls = det[5]
                cal.append(str(colors[int(cls)]))
                cv2.rectangle('demo.jpg', (x, y), (w, h), (0, 255, 0), 2)
                cv2.putText('demo.jpg', colors[int(cls)], (x, y - 10), fontFace=cv2.FONT_HERSHEY_SIMPLEX, fontScale=0.6,
                            color=(255, 255, 255), thickness=2)

            count_products = counter(cal)
            products = dict_to_str(count_products)
            cv2.imwrite('demo.jpg', frame)
            return products, total_product_count
    except Exception as e:
        print(e)
        return "ERORR", "Unknown"

    yield (b'--frame\r\n'
           b'Content-Type: image/jpeg\r\n\r\n' + open('demo.jpg', 'rb').read() + b'\r\n')

def video_feed(request):
return StreamingHttpResponse(stream(), content_type='multipart/x-mixed-replace; boundary=frame')`

**
We created a guest house detection learning model that detects colors through yolov8m. In this state, I wrote a code after watching YouTube for real-time guest house detection, but it doesn't work from cv2. correctangle. The error code is as follows.

**
OpenCV(4.7.0) 👎 error: (-5:Bad argument) in function 'rectangle'

Overload resolution failed:

• img is not a numpy array, neither a scalar
• Expected Ptrcv::UMat for argument 'img'
• img is not a numpy array, neither a scalar
• Expected Ptrcv::UMat for argument 'img'

**
Please let me know which one I should modify.

[Hamza-Bin-Aamir]

The issue

cv2.rectangle() does not take the name of the image file, it needs (as the error says) a numpy array

How to fix it

you can achieve this by moving the cv2.imwrite() function below the try except blocks
and changing the cv2.rectangle() and cv2.putText() functions to:

cv2.rectangle(frame , (x, y), (w, h), (0, 255, 0), 2) 

cv2.putText(frame , colors[int(cls)], (x, y - 10), fontFace=cv2.FONT_HERSHEY_SIMPLEX, 
    fontScale=0.6, color=(255, 255, 255), thickness=2)