A fast block-matching algorithm for motion estimation is described for interframe image coding. Utilizing the fact that the motion is searched by a macroblock basis while the compression is performed by a block basis in many video compression standards, the proposed algorithm produces high PSNR and fast computation while keeping the bit-rate as low as those of conventional fast algorithms. The ...

In block based motion estimation algorithms, computation is reduced by limiting the number of candidate search points within the search window or simplifying the distortion measurement criterion for block matching. Integral frame based block motion estimation algorithms have been suggested in literature which drastically reduce computation cost. However, these algorithms have a serious drawback...

We are working to develop beating-heart atrial septal defect (ASD) closure techniques using real-time 3-D ultrasound guidance. The major image processing challenges are the low image quality and the high frame rate. This paper presents comparative results for ASD tracking in sequences of 3D cardiac ultrasound. We introduce a block flow technique, which combines the velocity computation from opt...

An important problem when using the Block Matching Algorithm to track objects is how to update the reference block to take account of the changing target appearance. This paper investigates and reports on the accuracy and stability of a variety of update strategies and on the robustness of these strategies to image noise. These strategies are applicable where an object is being tracked using th...

The only trouble with Richard Smith, for 13 years Editor of the British Medical Journal, is that he writes well but tends to repeat himself. Editors, and ex-editors, are a small group in the medical world, but we like to think we have been influential. This book is a series of stories of Richard Smith’s interaction with prospective authors, medical researchers of all sorts, the authorities of t...