Very low bit rate video coding using H.263 coder
Very low bit rate video coding using H.263 coder
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使用 H.263 编码器进行极低比特率视频编码
DOI：
10.1109/76.499839
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发表时间：
1996
期刊：
影响因子：
--
通讯作者：
Andrew Millin
中科院分区：
文献类型：
--
作者：
K. Ngan;D. Chai;Andrew Millin
最近，ITU-T建立了一个草案标准，H. 263，以用作小于64 kb/s的甚低比特率视频编码的可能标准。它基于ITU-T H.261视频会议标准。本文提供了一个H.263编码器的性能分析，目的是建立其操作参数和限制时，在非常低的比特率。然后，通过选择所需的一组操作参数来优化其性能。H.263编码器在非常低的比特率下工作时会受到“阻塞”效应的影响。为了提高编码图像的主观质量，离散余弦变换（DCT）系数在量化之前使用视觉量化矩阵进行加权。仿真结果表明，该方法提高了峰值信噪比（PSNR）值在所有测试的比特率，但更重要的是，感知的视觉质量显着改善，通过减少恼人的“阻塞”的影响。
Recently, ITU-T established a draft standard, H.263 to he used as a possible standard for very low bit rate video coding at less than 64 kb/s. It is based on the ITU-T H.261 standard for videoconferencing. This paper provides an analysis of the performance of H.263 coder with the aim of establishing its operational parameters and limitations when operating at very low bit rates. Its performance is then optimized by selecting the desired set of operational parameters. The H.263 coder suffers from "blocking" effects when operating at very low bit rates. To improve the subjective quality of the coded images, the discrete cosine transform (DCT) coefficients are weighted using a visual quantization matrix before quantization. Simulation results showed that the proposed method increases the peak signal-to-noise ratio (PSNR) values at all bit rates tested, but more importantly, the perceived visual quality is improved significantly by reducing the annoying "blocking" effects.