A study on efficient compression of multi-focus images for dense Light-Field reconstruction

Light-Field enables us to observe scenes from free viewpoints. However, it generally consists of 4-D enormous data, that are not suitable for storing or transmitting without effective compression. 4-D Light-Field is very redundant because essentially it includes just 3-D scene information. Actually, although robust 3-D scene estimation such as depth recovery from Light-Field is not so easy, a method of reconstructing Light-Field directly from 3-D information composed of multi-focus images without any scene estimation is successfully derived. Previously, based on the method, Light-Field compression via synthesized multi-focus images as effective representation of 3-D scenes was proposed. In this paper, we study efficient compression of multi-focus images synthesized from dense Light-Field by using DWT instead of DCT-based compression in order to suppress degradation such as block noise. Quality of reconstructed Light-Field is evaluated by PSNR and SSIM for analyzing characteristics of residuals. Experimental results reveal that our method is much superior to Light-Field compression using disparity-compensation at low bit-rate.