The images generated are based on two things:

1). the code within the systems

2). the data entered into the system.

Those images are the result of how the data is processed by the code. Even if you put in a random number generator, the code processes those numbers based on it internal code constraints.

Now a well designed and built code base may be able to generate every image of the same dimensions. You can certainly write code that can exhaustively generate every possible image, but the question here is whether this exhaustive generation is intelligent.