It is contrary to Islam. The quran says God cannot be compared with anything. If you can compare anything at all with God, then he is not God. God has no conceivable form. There is no need to speak to God in front of a picture. That picture is like a statue and is considered idol worship even if you intend to be worshiping God. And no, just because you are looking at a picture that a human painted it does not at all give you any more of an idea of what God's physical form is. Why do you think God even has a physical form? Does absolute perfection have a specific form? That is Islam's point of view and although I am not a muslim I agree, and please forgive my bluntness but I think worshiping a picture or statue is silly. And another thing, not only is everything God's but it is also part of God. So yes, he knows what your intentions are because since you are part of Him, He knows everything you're thinking. So lastly, it only takes a thought to communicate with God.
Why can nothing be compared to God if God is everything? God is the beauty in nature, God is the love we experience, God is the guide within. He is everything we know and much, much more. There might not be a need to speak to God who is manifest in/as a picture, but perhaps this is useful to the individual who has trouble expressing his/her love/intentions/emotions to the non-physical. Not everyone is at the stage where they are able to see God in everything or fully express themselves emotionally in thought/prayer. For those people is it silly? I don't think so, personally.
Hindus have an idea of God's personal feature because of the scriptures, not because of pictures. The art is derived from scripture, mystical experience/perception and historical accounts (because Vishnu has appeared in form on this earth numerous times).
You asked: Does absolute perfection have a specific form?
Firstly, who knows? Secondly, Hinduism does not reveal a single form. God has unlimited forms. He is everything. The shark is his form, the flower is His form, the temple is His form, the scripture is His form and yes, even the picture is His form. Is there a main form? Perhaps. I come from the line that sees Vishnu as the very essence of Everything and thus the essential manifestaiton. But no, this manifestation is not concievable to the human mind because we have not realised God. We have not realised much of anything yet. So if we can concieve anything at all it is from the small amount we know of from the list I provided and through our love and devotion we explore our God in images and song and prayer and imagination and in our daily lives. Everything is meant to be for God. If I am always thinking of God then as an artist I would love to depict Him the way I see Him, even if it is innaccurate. I don't understand what could possibly be wrong with that as it is an expression of my love and God -is- Love and love is the whole point of existence.