A digital still camera image processing system on a chip, different from the video camera system, is presented for mobile phone to reduce the power consumption and size. A new color interpolation algorithm is proposed to enhance the image quality. The system can also process fixed patten noise (FPN) reduction, color correction, gamma correction, RGB/YUV space transfer, etc. The chip is controlled by sensor registers by inter-integrated circuit (I2C) interface. The voltage for both the