We present a reconstruction algorithm that can restore the captured 4D light field from a portable plenoptic
camera without the need for calibration images. An efficient and robust estimator is proposed to accurately
detect the centers of microlens images. Based on that estimator, parameters that model the centers of
microlens array images are obtained by solving a global optimization problem. To further enhance the
quality of reconstructed multi-view images, a novel 4D demosaicing algorithm based on kernel regression
is also proposed. Our experimental results show that it outperforms the state of art algorithms.