Former PhD-student at the
Division of Medical Informatics . I worked with Quality
estimation for image sequences in VISIT, a project sponsored by
the Swedish Foundation of Strategic Research (SSF). My academic
advisor was Prof. Hans Knutsson. The project was carried out
in cooperation with Robert Forchheimer at the department of
Electrical Engineering, Linköping University.
This paper presents a novel method for performing fast estimation of data samples on a desired output grid from samples on an irregularly sampled grid. The output signal is estimated using integration of signals over a neighbourhood employing a local model of the signal using discrete filters. The strength of the method is demonstrated in motion compensation examples by comparing to traditional techniques.
Keywords
Medical and Health Sciences
BIBTEX
@article{diva2:242416,
author = {Andersson, Kenneth and Westin, C.-F. and Knutsson, Hans},
title = {{Prediction from off-grid samples using continuous normalized convolution}},
journal = {Signal Processing},
year = {2007},
volume = {87},
number = {3},
pages = {353--365},
}
This paper presents new methods for use of dense motion fields for motion compensation of interlaced video. The motion estimation is based on previously decoded field-images. The motion is then temporally predicted and used for motion compensated prediction of the field-image to be coded. The motion estimation algorithm is phase-based and uses two or three field-images to achieve motion estimates with sub-pixel accuracy. To handle non-constant motion and the specific characteristics of the field-image to be coded, the initially predicted image is refined using forward motion compensation, based on block-matching. Tests show that this approach achieves higher PSNR than forward block-based motion estimation, when coding the residual with the same coder. The subjective performance is also better.
Keywords
Medical and Health Sciences
BIBTEX
@article{diva2:244816,
author = {Andersson, Kenneth and Andersson, Mats and Johansson, Peter and Forchheimer, Robert and Knutsson, Hans},
title = {{Motion compensation using backward prediction and prediction refinement}},
journal = {Signal Processing: Image Communication},
year = {2003},
volume = {18},
number = {5},
pages = {381--400},
}
@inproceedings{diva2:244841,
author = {Andersson, Kenneth and Knutsson, Hans},
title = {{Multiple hierarchical motion estimation}},
booktitle = {Signal Processing, Pattern Recognition and Applications SPPRA,2002},
year = {2002},
pages = {80--},
}
Kenneth Andersson, Peter Johansson, Robert Forchheimer, Hans Knutsson, "Backward-forward motion compensated prediction", Advanced Concepts for Intelligent Vision Systems ACIVS02,2002, 2002.
KeywordsBiBTeX
Keywords
Medical and Health Sciences
BIBTEX
@inproceedings{diva2:244840,
author = {Andersson, Kenneth and Johansson, Peter and Forchheimer, Robert and Knutsson, Hans},
title = {{Backward-forward motion compensated prediction}},
booktitle = {Advanced Concepts for Intelligent Vision Systems ACIVS02,2002},
year = {2002},
}
@inproceedings{diva2:249822,
author = {Andersson, Kenneth and Andersson, Mats and Knutsson, Hans},
title = {{A perception based velocity estimator and its use for motion compensated prediction}},
booktitle = {SCIA 2001 Scandinavian Conference on Image Analysis,2001},
year = {2001},
pages = {493--},
}
@phdthesis{diva2:250370,
author = {Andersson, Kenneth},
title = {{Quality and motion estimation for image sequence coding}},
school = {Linköping University},
type = {{Linköping Studies in Science and Technology. Thesis No. 928}},
year = {2002},
address = {Sweden},
}