It would seem to me that direct eye contact is anything that we are able to look at, observe & focus our mind on.

Usually the term direct eye contact is used in relationship to another person.....where you look at their eyes when you are talking to them, but it's more about the connection between the 2 people where they are looking directly into your eyes as much as you looking into theirs......but I can definitely see how it could relate to a picture......would mean looking at it, focusing on it & concentrating your mind on what you are seeing & thinking about the picture.