An 8× 8-block based motion estimation using Kalman filter (original) (raw)

An 8x8-Block Based Motion Using Kalman Filter

It is now quite common in the pel-recursive approaches for motion estimation, to find applications of the Kalman filtering technique both in time and frequency domains. In the block-based approach, very few approaches are available of this technique to refine the estimation of motion vectors resulting from fast algorithms such as the three step on a 16x16-block basis. This paper proposes an 8x8-block based motion estimation which uses the Kalman filtering technique to improve the motion estimates resulting from both the three step algorithm and the 16x16-block based Kalman application of . The statespace representation uses a first order auto-regressive model. Comparative results obtained for different classes of video sequences are presented.

A new block-based motion estimation algorithm

Signal Processing: Image Communication, 1992

The conventional motion estimation algorithms used in digital television coding can roughly be classified into two categories, namely the block-matching method and the recursive method. Each of them has its own strong points. In this paper, a new type of block-based motion estimation algorithm is presented, which is based on the block-recursive (gradient) method and makes use of some of the merits of the block-matching method. For a moderate translational motion, motion estimation with a subpel precision can conveniently be obtained with only a couple of recursive searches, and for a violent or complicated motion which cannot be estimated by any block-based algorithm, the local minimum of prediction errors can always be found. Our experiments show that the proposed algorithm is efficient and reliable, and obviously superior to the conventional block-recursive algorithms and the fast block-matching algorithms. The performance of the proposed algorithm tends almost to the optimum of the full search algorithm with the same estimation precision, but the computational effort is much less than that of the full search algorithm.

A New Pel-Recursive Kalman-Based Motion Estimation Method

We present in this paper a new pel-recursive algorithm for estimating the displacement vector field in image sequences. Firstly we use a brightness-offset term in the motion constraint equation. We follow the Kalman approach to formulate the estimation problem. The state vector of dimension 3 is composed of the displacement vector and the brightness offset. The extended Kalman filter is used to estimate this state vector. The new algorithm is applied on two normalized TV sequences and it is shown that the new algorithm is always better than the commonly used algorithms. The mean square displaced frame difference obtained is about 20% less in comparison with the commonly used algorithms.

Architectural Study of a Block-Recursive Motion Estimation Algorithm

Real-Time Imaging, 1997

Architectural Study of a Block-Recursive Motion Estimation Algorithm he block-recursive algorithm for motion estimation is an option to classical methods like blockmatching usually used in conventional coding schemes based on motion compensation. The Tbl ock-recursive algorithm considered in this study has been developed at IRISA in the Temis group. It is composed of three steps: estimation, deterministic relaxation, and quadtree region splitting. These steps are iteratively executed until convergence. To be fully exploitable, a specialized VLSI architecture for motion estimation must satisfy the following features: real-time performance, modularity, easy external interfacing, flexibility and reduced internal complexity. In this paper, we analyse these different features with regards to the numerous parameters of the considered block-recursive algorithm. The influence of parameters on the quality of the coding algorithm is measured through numerous simulations. Architectural mechanisms required for an efficient implementation are also presented and discussed. This study falls within the framework for derivation of a specialized parallel architecture from the initial sequential algorithm specification.

Performance Analysis of Block Based Motion Estimation Algorithms Using MATLAB

International Journal of Advanced Research in Electrical, Electronics and Instrumentation Engineering, 2015

Performance of different block matching motion estimation algorithms are analysed and compared with respect to their result of PSNR and computational complexity. From this analysis, we have found that the full search (FS) technique produces better quality image as it gives better performance in PSNR calculation, but takes larger number of search points whereas diamond search (DS) algorithm takes a few number of search points and also give average performance in PSNR calculation. Other algorithms (i.e. TSS, NTSS, and FSS) take lesser number of search points, but produce distorted image because of poor PSNR performance. As DS algorithm take fewer number of search points, it is faster. The image quality of DS can be improved by increasing the PSNR value. Therefore, it is still a research area for developing a fast block based motion estimation algorithm for better quality image with less number of searching points. .

A Complexity and Quality Evaluation of Block Based Motion Estimation Algorithms

Acta Polytechnica, 2005

Motion estimation is a method, by which temporal redundancies are reduced, which is an important aspect of video compression algorithms. In this paper we present a comparison among some of the well-known block based motion estimation algorithms. A performance evaluation of these algorithms is proposed to decide the best algorithm from the point of view of complexity and quality for noise-free video sequences and also for noisy video sequences.

Efficient Block Motion Estimation using Sector Based Approach

2007

This paper suggests a simple scheme in which the search pattern is divided into a number of sectors based on the spatio-temporal correlation information. In the first step five neighboring blocks are searched for finding the predicted motion vector. The predictive motion vector thus obtained is chosen as the initial search center. This predictive search center is found to be closer to the global minimum and thus decreases the effects of the monotonic error surface assumption and its impact on the motion field estimates. Secondly the prediction information is used to obtain the direction of predicted motion vector. Based on the direction of predicted motion vector the search area is divided into four sectors. Final search pattern is adaptive and depends on the sector selected and significantly reduces the computational complexity. Experiments show the speed improvement of the proposed algorithm as compared to other fast search algorithms, in addition the image quality measured in terms of PSNR also shows good results.

A Novel Hybrid Approach for Fast Block Based Motion Estimation

International Journal of Interactive Multimedia and Artificial Intelligence

The current work presents a novel hybrid approach for motion estimation of various video sequences with a purpose to speed up the entire process without affecting the accuracy. The method integrates the dynamic Zero motion pre-judgment (ZMP) technique with Initial search centers (ISC) along with half way search termination and Small diamond search pattern. Calculation of the initial search centers has been shifted after the process of zero motion pre-judgment unlike most the previous approaches so that the search centers for stationary blocks need not be identified. Proper identification of ISC dismisses the need to use any fast block matching algorithm (BMA) to find the motion vectors (MV), rather a fixed search pattern such as small diamond search pattern is sufficient to use. Half way search termination has also been incorporated into the algorithm which helps in deciding whether the predicted ISC is the actual MV or not which further reduced the number of computations. Simulation results of the complete hybrid approach have been compared to other standard methods in the field. The method presented in the manuscript ensures better video quality with fewer computations.

Block unshifting high-accuracy motion estimation: A new method adapted to super-resolution enhancement

Signal Processing: Image Communication, 2018

Sub-pixel motion estimation plays a vital role in a multitude of video applications, including encoding, audiovisual archiving/heritage and super-resolution enhancement. Most existing block-based methods rely on the implicit assumption that blocks can be accurately predicted through appropriate shifts. In particular, shifted blocks in the target frame are estimated from the associated anchor frame blocks. The present paper introduces a different strategy, which discards this assumption and treats anchor and target frame blocks equally, as sub-pixel shifted versions of an unavailable implied block. The new method attempts to construct this implied block and, by calculating the "imaginary" motion vectors that relate it to the two existing blocks, it estimates the wanted motion vectors more accurately. This approach aims at extracting motion vectors that more accurately represent the actual movements of objects, minimizing the interpolation error that is associated with sub-pixel shifting, which manifests as blurring and a lowering of contrast. The new method focuses on accurate motion estimation, paying less attention to the associated computational load. Hence, the approach is both inspired from, and proposed for, super-resolution enhancement scenarios, where higher definition motion image sequences are estimated from their available lower definition counterparts. In order to implement the new strategy, an algorithm for reversing the bilinear sub-pixel shift of a block (unshifting) is implemented and validated. Comparisons between original blocks of images and blocks that have been shifted and unshifted back to their original coordinates showcase the accuracy of the unshifting process. The proposed motion estimation method is evaluated through a number of different experimental assessment procedures and metrics, comparing it to existing high-accuracy state-of-theart motion estimation methods.