Two-stage picture padding for high efficiency video coding
With the exponential growth of digital cameras and the aid of powerful video editing softwares, videos with various resolutions become ever more popular. Therefore, there is a great demand for video coding schemes supporting arbitrary resolutions with higher efficiency. In the latest standard, only a simple padding with direct copying is adopted to meet this requirement, and the coding efficiency is still unsatisfactory. To improve the performance, a novel two-stage picture padding is proposed in this paper. Based on the adopted transform, an efficient residual padding is employed in the first stage to minimize the burdened coding bits of padded parts. To obtain a reference picture with high-quality boundary, a template matching based approach is also proposed to rearrange the padded pixels in the second stage. Experimental results reveal that on top of HEVC, our method offers the performance with 2.1%, 1.8%, and 1.5% BD-rate reduction for RA-Main, LDB-Main and LDP-Main configurations, respectively. Compared with the state-of-the-art algorithm, it still outperforms for kinds of test sequences under all configurations.