You’re confusing "picture" with "photograph"
I’ve probably never met you, have no idea what you look like and yet I could quite happily draw a picture of you juggling 5 clubs. The picture would exist, and it would be of you juggling 5 clubs. 
I could even use a drawing package on my pc to draw a picture of you juggling 5 clubs and save it as a jpg. It would be a picture of you, juggling 5 clubs, in jpg format, and may appear somewhere in the depths of pi.
OK, so it might not be a very accurate picture of you, but it would still exist. pictures don’t have to depict reality - look at the work of M.C. Escher or Salvador Dali. I doubt very much that any of the subjects that they painted exist in reality - but the pictures still exist.
You might think you were on safer ground with "video" - but not so!
There exists video of a grown man wearing spandex swinging around a city attached to a large spider-web. To my knowlegde, this has never actually happened, and is a complete work of fiction. However, the video does exist
I know. How? I paid far too much money to watch that pile of toss in the cinema that’s how.
-Paul I guess it’s perfectly possible that this post might appear somewhere in the depths of pi, but it’s equally possible that there also exists a spellchecked and proofread version.
 it wouldn’t be a very good picture as I can’t draw for shit!  I still can’t quite believe I went back to see if the sequal was any better - it wasn’t.