Look at the background wall of friends circle. How do you know if it is a network map?

I can't access the pictures of friends circle on the Internet to judge whether they are from the Internet. But here are some clues that may indicate that the photos came from the Internet: 1. Image pixels are blurred, distorted or uncoordinated. This may indicate that the picture has been stretched or resized to fit the background wall of the circle of friends. 2. The photo theme has nothing to do with the content of the circle of friends. If the photo has nothing to do with the theme of the text, it may mean that the photo was just randomly selected from the Internet. 3. The photo quality is too good. If the photos are high-definition and brightly colored, it may mean that the photos were not taken by ordinary mobile phones, but by professional photographers or institutions. 4. A logo or watermark will appear on the photo. If there is a photographer's logo or watermark in the photo, it may indicate that the photo is from the Internet. Please note that these clues do not determine whether the photos are from the Internet, but only some possible signs. I believe you can draw a more accurate conclusion through your own judgment.