H.264/AVC Intra-only Coding (iAVC) and Neural Network Based Prediction Mode Decision

The requirement to transmit video data over unreliable wireless networks is anticipated in the foreseeable future. Significant compression ratio and error resilience are both needed for applications including tele-operated robotics, vehicle-mounted cameras, sensor network, etc. Block-matching based inter-frame coding techniques, such as MPEG-x and H.26x, do not perform well in these scenarios due to error propagation between frames. Intra-only coding technologies, such as Motion-JPEG, exhibit better recovery from network data loss at the price of higher data rates. In order to address these issues, an intra-only coding scheme of H.264/AVC (iAVC) is proposed. In this approach, each frame is coded independently as an I-frame. In order to speed up the coding procedure, we propose a neural network based intra-only prediction mode decision approach, which has the potential to significantly reduce coding complexity. Frame copy is applied to compensate for packet loss. The proposed approach is a good balance between compression performance, memory usage, and error resilience. It achieves compression performance comparable to Motion-JPEG2000, with lower complexity. Low computational complexity and memory usage are very crucial to mobile stations and devices in wireless networks.

I. Introduction

The requirement to transmit video data over unreliable wireless network (with the possibility of packet loss) will be present in the foreseeable future. It is necessary to develop advanced video compression techniques that are well-suited to the network environment in applications such as teleoperated robotics, vehicle-mounted cameras, sensor network, etc. Significant compression ratio and error resilience are both needed for such type of operations. Block-matching based inter-frame coding techniques, including MPEG-x and H.26x, achieve significant compression rations. However, in these types of schemes, inter-frame coding dependencies exist. Thus, packet loss within the I-frame of the Group-Of-Pictures (GOP) will cause disastrous video quality degradation (Fig. 1). Numerous wireless applications use intra-only coding technologies such as Motion-JPEG (MJ), which exhibit better recovery from network data loss but at the price of higher data rates. In order to address these issues, an intra-only coding scheme of H.264/AVC is proposed. Figure 1. Error propagation in a GOP