Hi, I don't think you will find a chip, composite is now old technology, and I'd say that a stand along IC that does that job would not exist.
They would be integrated into a full blown video processing chip, so go good luck.
Tom...... 
Hi, I don't think you will find a chip, composite is now old technology, and I'd say that a stand along IC that does that job would not exist.
They would be integrated into a full blown video processing chip, so go good luck.
Tom......