New half-pixel accuracy motion estimation algorithms for low bitrate video communications

Mahdavi Nasab, H ; Sharif University of Technology | 2008

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  1. Type of Document: Article
  2. Publisher: Sharif University of Technology , 2008
  3. Abstract:
  4. Fractional-pixel accuracy Motion Estimation (ME) has been shown to result in higher quality reconstructed image sequences in hybrid video coding systems. However, the higher quality is achieved by notably increased Motion Field (MF) bitrate and more complex computations. In this paper, new half-pixel block matching ME algorithms are proposed to improve the rate-distortion characteristics of low bitrate video communications. The proposed methods tend to decrease the required video bandwidth, while improving the motion compensation quality. The key idea is to put a deeper focus on the search origin of the ME process, based on center-bias characteristics of low bitrate video MFs. To employ the benefits of Mesh-based ME (MME), the introduced algorithms are also examined in the framework of a fast MME scheme. Experimental results show the efficiency of the proposed schemes, especially when employed in the MME approach, so that a reduction of more than 20% in the MF bitrate is achieved when employing typical QCIF formatted image sequences. © Sharif University of Technology
  5. Keywords:
  6. Bandwidth ; Electric distortion ; Image coding ; Mesh generation ; Motion compensation ; Pixels ; Signal distortion ; Video signal processing ; Visual communication ; Block Matching ; Half-pixel accuracy ; Hybrid video coding ; Low Bit Rate ; Mesh-based ME ; Motion estimation algorithm ; Rate distortion characteristics ; Reconstructed image ; Motion estimation ; Accuracy assessment ; Algorithm ; Estimation method ; Pixel
  7. Source: Scientia Iranica ; Volume 15, Issue 6 , 2008 , Pages 507-516 ; 10263098 (ISSN)
  8. URL: http://scientiairanica.sharif.edu/article_3082.html