Low Complexity Pruned DCT Approximation for Image Compression in Wireless Multimedia Sensor Networks

In this paper we propose a novel efficient low-complexity Discrete Cosine Transform (DCT) approximation using only 14 additions. The proposed transformation is based upon a pruned version of the Signed DCT (SDCT). Associated with a JPEG compression chain, this DCT approximation ensures a very good rate-distortion compromise, a very low computational complexity and a significant compatibility with the exact DCT. The proposed transformation is very suitable for the limited energy resource wireless multimedia sensor networks (WMSNs) requiring very low bitrates and other embedded systems. Simulation results show the superiority of the proposed fast algorithm compared to any existing pruned DCT approximations.