چكيده لاتين :
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 MMEa pproach,
so that a reduction of more than 20% in the MF bit rate is achieved when employing typical
QCIF formatted image sequences
