In your opinion, What is a brand image?

The impression in the consumers' mind of a brand's total personality (real and imaginary qualities and shortcomings). Brand image is developed over time through advertising campaigns with a consistent theme, and is authenticated through the consumers' direct experience.

That's what I install in a mind and heart of some group of individuals :) I control the way a certain targeted group of people look at/ think of a particualr product.

In simple words: it's how your existing or to-be customer sees your product. It could be imaginary as well!