Currently, I am working on a code snippet that utilizes OpenCV to detect the largest contour or object within an image. The snippet successfully creates the bounding box, but I am looking for the best method to save this bounding box as a separate image file. Essentially, I want to extract and store the largest object within the image as a new JPEG file. Below is the code I have been experimenting with:
import numpy as np
import cv2
font = cv2.FONT_HERSHEY_SIMPLEX
lineType = cv2.LINE_AA
im = cv2.imread('test/originals/8.jpg')
im_ycrcb = cv2.cvtColor(im, cv2.COLOR_BGR2HSV)
ball_ycrcb_mint = np.array([0, 90, 100],np.uint8)
ball_ycrcb_maxt = np.array([25, 255, 255],np.uint8)
ball_ycrcb = cv2.inRange(im_ycrcb, ball_ycrcb_mint, ball_ycrcb_maxt)
cv2.imwrite('test/outputs/output8.jpg', ball_ycrcb) # Second image
areaArray = []
count = 1
_, contours, _ = cv2.findContours(ball_ycrcb, cv2.RETR_EXTERNAL, cv2.CHAIN_APPROX_SIMPLE)
for i, c in enumerate(contours):
area = cv2.contourArea(c)
areaArray.append(area)
areaLargest = np.argmax(areaArray)
areaLargestMax = max(areaArray)
areaLargestCnt = contours[areaLargest]
x, y, w, h = cv2.boundingRect(areaLargestCnt)
roi = im[y:y+h, x:x+w]
cv2.imwrite('test/contours.jpg', im)
if area == areaLargestMax and area > 10000:
cv2.drawContours(im, contours, i, (255, 0, 0), 7)
cv2.rectangle(im, (x, y), (x+w, y+h), (0,255,0), 7)
cv2.imwrite('test/outputs/output9.jpg', im)