Does Twitter check for reposted images?

Hey guys
I was wondering if Twitter check for reposted content, what do you think?
If its true , then I guess comparing all the images would be too big resource consuming mission
So what could they do except for checksum/hash comparing?
I was thinking to start changing the checksum of my content to prevent any duplications
What do you think?

i dont think twitter does that, because i have a seen a lot of profile with same uploaded images.

probably not, twitter doesn't check it