北京邮电大学学报

  • EI核心期刊

北京邮电大学学报 ›› 2007, Vol. 29 ›› Issue (s1): 10-13.doi: 10.13190/jbupt.2007s1.10.xiezhg

• 论文 • 上一篇    下一篇

基于DCT系数分布的全零DCT系数块的预先判别方法(增刊)

谢正光,刘勇,刘文军,杨铁军   

  1. 北京邮电大学继续教育学院(即北京邮电大学通信网络综合技术研究所;北京邮电大学培训中心)
  • 收稿日期:2006-10-13 修回日期:2006-11-02 出版日期:2007-06-30 发布日期:2007-06-30

Early Detection of All-Zero DCT Coefficients Block Based on DCT Coefficients Distribution Model

XIE Zheng-guang, LIU Yong, LIU Wen-jun, YANG Tie-jun   

  • Received:2006-10-13 Revised:2006-11-02 Online:2007-06-30 Published:2007-06-30

摘要: 低码率视频编码时,经帧间预测后得到的运动补偿数据通常很小,对这些数据再进行DCT和量化后其DCT系数往往全为零。为减少编码器的运算量,提出了预先判断全零DCT系数块的方法。在分析现有判别方法对全零系数块的误判与漏判的基础上,从二维整数DCT 变换,量化和DCT系数的分布特性出发,提出了一种全新的判断方法,提高了判别效率,并给出了具有一般表示的判别式,可以应用于不同尺寸的变换块。实验结果表明,所提出的判别方法提高了全零DCT系数块的判别效率,与现有的方法比有高达35%的检出率。

关键词: 离散余弦变换, 全零系数块, DCT系数分布

Abstract: In video coding, the value of residual block produced by inter prediction is usually small. When the residual block is transformed and quantized, the discrete cosine transform (DCT) coefficients quantized are all zero, especially in low bit-rate video applications. The early detection technique proposed is to reduce the encoding computation complexity. If these residual blocks are pre-determined, and then they are not required to be DCT transformed and quantized. This is the so-called early detection method of all-zero DCT coefficients block (AZB). Based on analysis of the false-judgment and miss-judgment of the existing algorithms, the analysis of DCT coefficients distribution, characteristics of the integer DCT (IntDCT) and quantization, an innovative algorithm for early detection AZB is proposed. The experimental results show that the proposed algorithms improve the judge efficiency up to 35% higher than that of existing methodologies.

Key words: integer discrete cosine transform, all-zero coefficients block, DCT coefficients distribution model