Inter-layer FEC aided unequal error protection for multi-layer video transmission in mobile TV

摘要

Layered video coding creates multiple layers of unequal importance, which enables us to progressively refine the reconstructed video quality. When the base layer (BL) is corrupted or lost during transmission, the enhancement layers (ELs) must be dropped, regardless whether they are perfectly decoded or not, which implies that the transmission power assigned to the ELs is wasted. In this treatise, we propose an interlayer forward error correction (FEC) coded video transmission scheme for mobile TV. At the transmitter, the proposed interlayer (IL) coding technique implants the systematic information of the BL into the ELs by using exclusive-OR operations. At the receiver, the implanted bits of the ELs may be utilized for assisting in decoding the BL. Furthermore, the data partition mode of H.264 video coding is utilized as the source encoder, where the type B and type C partitions will assist in protecting the type A partition. The IL coded bitstream will then be modulated and transmitted over a multi-functional multiple-input multiple output (MF-MIMO) scheme for the sake of improving the system’s performance in mobile environments. The proposed system may be readily combined with the traditional unequal error protection (UEP) technique, where extrinsic mutual information (MI) measurements are used for characterizing the performance of our proposed technique. Finally, our simulation results show that the proposed system model outperforms the traditional UEP aided system by about 2.5 dB of Eb/N0 or 3.4 dB of peak signal-to-noise ratio (PSNR) at the cost of 21% complexity increase, when employing a recursive systematic convolutional code. Furthermore, unlike the traditional UEP strategies, where typically stronger FEC-protection is assigned to the more important layer, employing our proposed IL coding technique requires weaker FEC to the more important layer. For example, the system relying on channel coding rates of 0.85, 0.44 and 0.44 for the type A, type B and type C H.264 video partitions, respectively, achieves the best system performance when employing a recursive systematic convolutional (RSC) code.