You must be registered for see images
This along with the other images are definitely not drawings made by Obito because the thin black straight lines present in all images are indicative of photo printing, they are called striations
You must be registered for see images
Now that we have established that all of them are indeed photographs, we can analyze clearly the difference in age of the bottom left's photo from the rest
The bottom left photo featuring the couple are noticeably older than the other photos because of the jagged edges which indicates age from wearing and tearing
You must be registered for see images
Compared to the edges of the other photos which are smooth
You must be registered for see images
We can also ascertain the agedness of the bottom left photo based on the clip that is used to fastened it in Obito's wall
You must be registered for see images
Because the photograph is old, a binding clip is needed to fasten it.
Unlike the other photos that requires only thumbtacks because they are relatively new
You must be registered for see images
We can also determine that the adult woman in the bottom left photo is not Rin because of the lack of the markings in her cheeks like Rin's
You must be registered for see images
You must be registered for see images
Also the woman in the bottom left photo has curled hair ends unlike Rin's
You must be registered for see images
The man in the bottom left photo is definitely an Uchiha because of the design of the collar of the shirt which are worn by Uchiha men.
You must be registered for see images
And the baby in the bottom left photo is most probably a male since the drawing strokes makes it similar to the father's hair
You must be registered for see images
You must be registered for see images
The baby is most certainly Obito.
Based on the the age of the photograph and the evidences at hand, the logical conclusion is:
Obito is a war orphan (and most probably an only child) and his parents died long before the events of Kakashi Gaiden. He is meant to be a parallel of Naruto in that they were orphaned at very young age.
