Abstract
This research chooses H.264/AVC as the experimental platform. This paper uses the pixel-mean interpolation (adopted by the error concealment method for the H.264 standard in JM 18.4 reference software) to improve the video quality when the decoded image blocks are partially in error. However, this method may fail to achieve better video quality and produce unwanted effects such as edge blurring effect or blocking artifact. To solve this problem, this study proposes a new spatio-temporal error concealment method which can be applied for I-frame and P-frame. Unlike the previous approaches that can be applied for I-frame or P-frame only. The proposed method applies global spiral, sub-block autologous spiral method and exploits the edge matching information. Based on the principle of edge's perpendicular bisector symmetry reconstruction, system evaluates the potential edges in a corrupted MB and performs the error concealment algorithm for each single frame. The proposed method enables to recovery the fidelity of edge in the corrupted MB, which is brilliant than the previous methods. Based on our observation, it can also recover a corrupted MB containing multi-edges. The proposed method can provide more accurate result than that of the Boundary Matching Algorithm(BMA), and Spatio-temporal Boundary Matching Algorithm(STBMA) costs a great of computational complexity, resulting in longer processing time. To reduce the computation time, this study also proposes an edge ratio analysis mechanism, where corrupted MBs are either concealed by the proposed method or the pixel-mean interpolation depending on the percentage of the number of the edge pixels in an MB. With this edge threshold analysis mechanism, the edge blurring and blocking effects can be strongly reduced with a slight increasing in computation time. The experimental results show that when Hall video sequence in P frame’s block error rate (BER) is 5%, the peak signal to noise ratio (PSNR) reaches as high as 58.99 dB, higher than BMA and STBMA with 1.46 dB and 0.72dB, respectively. In 10% BER, the proposed method outperforms BMA and STBMA both visually and in the objective measurement. In 20% BER, good error concealment performance can be achieved for the video with whatever complicated contents.