國立屏東商業技術學院 資訊工程系 ( 所 ) 多媒體技術發展實驗室 Laboratory of Multimedia Technology Development Department of Computer Science and Information Engineering Nation Pingtung Institute of Commerce A Study on H.264/AVC Motion Compensation with Fractional-pel 學生姓名：戴文明 信箱： 授課老師：李明錡 教授

第 2 頁，共 10 頁 Outline Abstract Introduction ◦1.1 General background information ◦1.2 Research Purpose 2013/06/24

第 3 頁，共 10 頁 Abstract 1.1 General background information H.264/AVC is the most well-known video compression coding standard, in which quarter resolution and motion compensation can achieve more accurate motion description. There are two steps of quarter-pel interpolation. First, the Wiener filter with fixed six coefficients produces half-pel. Second, the Bilinear interpolation produce quarter-pel. 2013/06/24

第 4 頁，共 10 頁 Abstract This paper proposes an interpolation of cubic convolution interpolation (CCI) with four coefficients in H.264/AVC standard. It can reduce the encoding time and increase the quality of quarter-pel. The proposed interpolation of CCI with bilinear can speed up the encoding time and increase the quality of video. 2013/06/24

第 5 頁，共 10 頁 Introduction Duo to the rapid development of computer and networks technology, it is a huge demand for people. Therefore, Video data compression can reduce not only capacity of video files but also time of transmission in network. There are two types of video compression: One is the lossless compression, the other one is lossy compression. 2013/06/24

第 6 頁，共 10 頁 Introduction Lossless compression is that the original and the decompressed data be identical and the exact original data to reconstructed from the compressed data. Lossy compression is that compresses data by losing some of it, so it is the original and the decompressed data be different. 2013/06/24

第 7 頁，共 10 頁 Introduction The advantage of using lossy compression that files size is smaller than with lossless compression. In recent year, Video compression technology main purpose is to meet on the internet and high-resolution transmission needs. 2013/06/24

第 8 頁，共 10 頁 Introduction 1.2 Research Purpose Spatial redundancy is the image pixel and the correlation between neighboring pixels, using the intra prediction to reduce spatial redundancy. Temporal redundancy is the correlation between sequence of image cause by too close, using the inter prediction to reduce temporal redundancy. 2013/06/24

第 9 頁，共 10 頁 Introduction To reduce temporal redundancy, when the image and the reference frame do motion estimation, the relative position of the two vector is motion vector (MV), each macroblock match a MV, and match minimum of Sum of Absolute Difference (SAD). Since moving objects, it is not fall fully on the integer pixel, resulting in inaccurate motion estimation, prediction and coding efficiency decreases. 2013/06/24

第 10 頁，共 10 頁 Introduction Therefore, H.261 standard used after fractional- pel resolution, using the interpolation process scaling the current and reference frame do motion estimation on the MV more accurately, to reduce the prediction error improves coding efficiency. 2013/06/24