Real-time digital zooming for mobile consumer cameras using directionally adaptive image interpolation and restoration

Abstract

In this digest, we present a novel real-time digital zooming method based on directionally adaptive image interpolation and restoration. The proposed method first estimates an edge direction using steerable filters and performs weighted smoothing along the estimated edge direction. Bi-cubic and bi-linear interpolations are selectively used according to the estimated edge direction. Degradation and artifacts caused by interpolation are removed by employing a directionally adaptive truncated constrained least squares (TCLS) filter. The proposed digital zooming method followed by image restoration provides high-quality magnified images which are similar to the result of computationally intensive super-resolution algorithms. The proposed method can be applied to real-time image processing, and embedded in the form of the finite impulse response (FIR) filtering structure. It is suitable for digital zooming system of mobile phone cameras, tablet PCs, and digital camcorders.