Research Of Error Concealment Based On Motion Vector

With the explosive growth of the Internet and the wireless network, video services over these networks are becoming more and more popular. As a result, several compression-centric coding standards, such as MPEG-2/4, H.263 and H.264, have been developed to transmit video sequences especially over bandwidth-limited channels. The common techniques employed by these video-coding standards include discrete cosine transform, motion estimation/motion compensation, and variable length coding. All of the techniques are successful as they exploit the spatial, temporal, and statistical redundancy in video streams to compress the same. However, highly compressed video bit streams are susceptible to transmission errors. These errors can propagate both spatially and temporally while decoding the current and subsequent video frames, thus leading to a severe degradation in the visual quality at the receiving side. A subclass of this error concealment in video communication is known as motion vector recovery (MVR). MVR techniques try to retrieve the lost motion information in the compressed video streams based on the available information in the locality of the lost data. The activities and practice in the area of MVR-based error concealment during the last two decades has been mainly elaborated, and analyses some of the most popular, simple, efficient and widely used MVR techniques. The main methods based MVR are Temporal Replacement (TR), Boundary Matching (BMA), Lagrange Interpolation (LAGI) and Polynomial Interpolation Model (PIM). This paper also presents a performance comparison results for these selected MVR techniques in simulation as well as in real-time video streaming environment.Based on the theoretical analysis, an temporal error concealment algorithm is proposed for H.264 Inter frame decoding to eliminate the error effect for Human Visual System (HVS). The simulation results show that the proposed algorithm can achieve better performance compared with the existing TEC methods. The proposed algorithm is pervasive to be used in the real-time multimedia communication systems with the video coding standard H.264.