why do some of my pictures have a cloud with an arrow pointing down?

[Android Central Question]

I just reset my tablet a few days ago, I did the one so I could keep my files. Now I have a lot of my pictures that show up white, with a cloud in the center, and a arrow pointing down.

 

[L0n3N1nja]

More information would help but I'm thinking they may be backed on the cloud and need to get downloaded again.