今天用python讀取和保存圖像時,發現讀取jpg的圖像,在保存爲jpg,再讀取時,兩個圖像的差會有很大不同。原因是,jpeg在保存的時會有損失,png格式爲無損保存。
import cv2
img1 = cv2.imread("test.jpg")
cv2.imwrite("test1.jpg",img1)
img2 = cv2.imread("test1.jpg")
img_diff = img1 - img2
cv2.imwrite("diff1.png",img_diff)
cv2.imshow("imgdiff1",img_diff)
cv2.waitKey(100)
cv2.imwrite("test2.png",img1)
img3 = cv2.imread("test2.png")
img_diff = img1 - img3
cv2.imwrite("diff2.png",img_diff)
cv2.imshow("imgdiff2",img_diff)
cv2.waitKey(100)
test.jpg
diff1.png
diff2.png