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2009


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On feature combination for multiclass object classification

Gehler, P., Nowozin, S.

In Proceedings of the Twelfth IEEE International Conference on Computer Vision, pages: 221-228, 2009, oral presentation (inproceedings)

project page, code, data GoogleScholar pdf DOI [BibTex]

2009

project page, code, data GoogleScholar pdf DOI [BibTex]


Thumb xl tracking iccv09
Segmentation, Ordering and Multi-object Tracking Using Graphical Models

Wang, C., Gorce, M. D. L., Paragios, N.

In IEEE International Conference on Computer Vision (ICCV), 2009 (inproceedings)

pdf [BibTex]

pdf [BibTex]


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Visual Object Discovery

Sinha, P., Balas, B., Ostrovsky, Y., Wulff, J.

In Object Categorization: Computer and Human Vision Perspectives, pages: 301-323, (Editors: S. J. Dickinson, A. Leonardis, B. Schiele, M.J. Tarr), Cambridge University Press, 2009 (inbook)

link (url) [BibTex]

link (url) [BibTex]


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Evaluating the potential of primary motor and premotor cortex for mutltidimensional neuroprosthetic control of complete reaching and grasping actions

Vargas-Irwin, C. E., Yadollahpour, P., Shakhnarovich, G., Black, M. J., Donoghue, J. P.

2009 Abstract Viewer and Itinerary Planner. Society for Neuroscience, Society for Neuroscience, 2009, Online (conference)

[BibTex]

[BibTex]


Thumb xl thumb screen shot 2012 10 06 at 12.02.32 pm
Modeling and Evaluation of Human-to-Robot Mapping of Grasps

Romero, J., Kjellström, H., Kragic, D.

In International Conference on Advanced Robotics (ICAR), pages: 1-6, 2009 (inproceedings)

Pdf [BibTex]

Pdf [BibTex]


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Polyp Segmentation in NBI Colonoscopy

Gross, S., Kennel, M., Stehle, T., Wulff, J., Tischendorf, J., Trautwein, C., Aach, T.

Abstract
Endoscopic screening of the colon (colonoscopy) is performed to prevent cancer and to support therapy. During intervention colon polyps are located, inspected and, if need be, removed by the investigator. We propose a segmentation algorithm as a part of an automatic polyp classification system for colonoscopic Narrow-Band images. Our approach includes multi-scale filtering for noise reduction, suppression of small blood vessels, and enhancement of major edges. Results of the subsequent edge detection are compared to a set of elliptic templates and evaluated. We validated our algorithm on our polyp database with images acquired during routine colonoscopic examinations. The presented results show the reliable segmentation performance of our method and its robustness to image variations.

link (url) DOI [BibTex]

link (url) DOI [BibTex]


Thumb xl nips2009b
An additive latent feature model for transparent object recognition

Fritz, M., Black, M., Bradski, G., Karayev, S., Darrell, T.

In Advances in Neural Information Processing Systems 22, NIPS, pages: 558-566, MIT Press, 2009 (inproceedings)

pdf slides [BibTex]

pdf slides [BibTex]


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Automatic recognition of rodent behavior: A tool for systematic phenotypic analysis

Serre, T.*, Jhuang, H*., Garrote, E., Poggio, T., Steele, A.

CBCL paper #283/MIT-CSAIL-TR #2009-052., MIT, 2009 (techreport)

pdf [BibTex]

pdf [BibTex]


Thumb xl screen shot 2012 06 06 at 11.24.14 am
Let the kernel figure it out; Principled learning of pre-processing for kernel classifiers

Gehler, P., Nowozin, S.

In Proceedings of the Conference on Computer Vision and Pattern Recognition (CVPR), pages: 2836-2843, IEEE Computer Society, 2009 (inproceedings)

doi project page pdf [BibTex]

doi project page pdf [BibTex]


Thumb xl thumb screen shot 2012 10 06 at 12.04.52 pm
Monocular Real-Time 3D Articulated Hand Pose Estimation

Romero, J., Kjellström, H., Kragic, D.

In IEEE-RAS International Conference on Humanoid Robots, pages: 87-92, 2009 (inproceedings)

Pdf [BibTex]

Pdf [BibTex]


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Grasp Recognition and Mapping on Humanoid Robots

Do, M., Romero, J., Kjellström, H., Azad, P., Asfour, T., Kragic, D., Dillmann, R.

In IEEE-RAS International Conference on Humanoid Robots, pages: 465-471, 2009 (inproceedings)

Pdf Video [BibTex]

Pdf Video [BibTex]


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4D Cardiac Segmentation of the Epicardium and Left Ventricle

Pons-Moll, G., Tadmor, G., MacLeod, R. S., Rosenhahn, B., Brooks, D. H.

In World Congress of Medical Physics and Biomedical Engineering (WC), 2009 (inproceedings)

[BibTex]

[BibTex]


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Geometric Potential Force for the Deformable Model

Si Yong Yeo, Xianghua Xie, Igor Sazonov, Perumal Nithiarasu

In The 20th British Machine Vision Conference, pages: 1-11, 2009 (inproceedings)

Abstract
We propose a new external force field for deformable models which can be conve- niently generalized to high dimensions. The external force field is based on hypothesized interactions between the relative geometries of the deformable model and image gradi- ents. The evolution of the deformable model is solved using the level set method. The dynamic interaction forces between the geometries can greatly improve the deformable model performance in acquiring complex geometries and highly concave boundaries, and in dealing with weak image edges. The new deformable model can handle arbi- trary cross-boundary initializations. Here, we show that the proposed method achieve significant improvements when compared against existing state-of-the-art techniques.

[BibTex]

[BibTex]


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Left Ventricular Regional Wall Curvedness and Wall Stress in Patients with Ischemic Dilated Cardiomyopathy

Liang Zhong, Yi Su, Si Yong Yeo, Ru San Tan Dhanjoo Ghista, Ghassan Kassab

American Journal of Physiology – Heart and Circulatory Physiology, 296(3):H573-84, 2009 (article)

Abstract
Geometric remodeling of the left ventricle (LV) after myocardial infarction is associated with changes in myocardial wall stress. The objective of this study was to determine the regional curvatures and wall stress based on three-dimensional (3-D) reconstructions of the LV using MRI. Ten patients with ischemic dilated cardiomyopathy (IDCM) and 10 normal subjects underwent MRI scan. The IDCM patients also underwent delayed gadolinium-enhancement imaging to delineate the extent of myocardial infarct. Regional curvedness, local radii of curvature, and wall thickness were calculated. The percent curvedness change between end diastole and end systole was also calculated. In normal heart, a short- and long-axis two-dimensional analysis showed a 41 +/- 11% and 45 +/- 12% increase of the mean of peak systolic wall stress between basal and apical sections, respectively. However, 3-D analysis showed no significant difference in peak systolic wall stress from basal and apical sections (P = 0.298, ANOVA). LV shape differed between IDCM patients and normal subjects in several ways: LV shape was more spherical (sphericity index = 0.62 +/- 0.08 vs. 0.52 +/- 0.06, P < 0.05), curvedness at end diastole (mean for 16 segments = 0.034 +/- 0.0056 vs. 0.040 +/- 0.0071 mm(-1), P < 0.001) and end systole (mean for 16 segments = 0.037 +/- 0.0068 vs. 0.067 +/- 0.020 mm(-1), P < 0.001) was affected by infarction, and peak systolic wall stress was significantly increased at each segment in IDCM patients. The 3-D quantification of regional wall stress by cardiac MRI provides more precise evaluation of cardiac mechanics. Identification of regional curvedness and wall stresses helps delineate the mechanisms of LV remodeling in IDCM and may help guide therapeutic LV restoration.

[BibTex]

[BibTex]


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Level Set Based Automatic Segmentation of Human Aorta

Si Yong Yeo, Xianghua Xie, Igor Sazonov, Perumal Nithiarasu

In International Conference on Computational & Mathematical Biomedical Engineering, pages: 242-245, 2009 (inproceedings)

[BibTex]

[BibTex]


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A Curvature-Based Approach for Left Ventricular Shape Analysis from Cardiac Magnetic Resonance Imaging

Si Yong Yeo, Liang Zhong, Yi Su, Ru San Tan, Dhanjoo Ghista

Medical & Biological Engineering & Computing, 47(3):313-322, 2009 (article)

Abstract
It is believed that left ventricular (LV) regional shape is indicative of LV regional function, and cardiac pathologies are often associated with regional alterations in ventricular shape. In this article, we present a set of procedures for evaluating regional LV surface shape from anatomically accurate models reconstructed from cardiac magnetic resonance (MR) images. LV surface curvatures are computed using local surface fitting method, which enables us to assess regional LV shape and its variation. Comparisons are made between normal and diseased hearts. It is illustrated that LV surface curvatures at different regions of the normal heart are higher than those of the diseased heart. Also, the normal heart experiences a larger change in regional curvedness during contraction than the diseased heart. It is believed that with a wide range of dataset being evaluated, this approach will provide a new and efficient way of quantifying LV regional function.

link (url) [BibTex]

link (url) [BibTex]


Thumb xl orthonormaity
In Defense of Orthonormality Constraints for Nonrigid Structure from Motion

Akhter, I., Sheikh, Y., Khan, S.

In Computer Vision and Pattern Recognition, 2009. CVPR 2009. IEEE Conference on, pages: 2447-2453, 2009 (inproceedings)

Abstract
In factorization approaches to nonrigid structure from motion, the 3D shape of a deforming object is usually modeled as a linear combination of a small number of basis shapes. The original approach to simultaneously estimate the shape basis and nonrigid structure exploited orthonormality constraints for metric rectification. Recently, it has been asserted that structure recovery through orthonormality constraints alone is inherently ambiguous and cannot result in a unique solution. This assertion has been accepted as conventional wisdom and is the justification of many remedial heuristics in literature. Our key contribution is to prove that orthonormality constraints are in fact sufficient to recover the 3D structure from image observations alone. We characterize the true nature of the ambiguity in using orthonormality constraints for the shape basis and show that it has no impact on structure reconstruction. We conclude from our experimentation that the primary challenge in using shape basis for nonrigid structure from motion is the difficulty in the optimization problem rather than the ambiguity in orthonormality constraints.

pdf [BibTex]

pdf [BibTex]


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Dynamic distortion correction for endoscopy systems with exchangeable optics

Stehle, T., Hennes, M., Gross, S., Behrens, A., Wulff, J., Aach, T.

In Bildverarbeitung für die Medizin 2009, pages: 142-146, Springer Berlin Heidelberg, 2009 (inproceedings)

Abstract
Endoscopic images are strongly affected by lens distortion caused by the use of wide angle lenses. In case of endoscopy systems with exchangeable optics, e.g. in bladder endoscopy or sinus endoscopy, the camera sensor and the optics do not form a rigid system but they can be shifted and rotated with respect to each other during an examination. This flexibility has a major impact on the location of the distortion centre as it is moved along with the optics. In this paper, we describe an algorithm for the dynamic correction of lens distortion in cystoscopy which is based on a one time calibration. For the compensation, we combine a conventional static method for distortion correction with an algorithm to detect the position and the orientation of the elliptic field of view. This enables us to estimate the position of the distortion centre according to the relative movement of camera and optics. Therewith, a distortion correction for arbitrary rotation angles and shifts becomes possible without performing static calibrations for every possible combination of shifts and angles beforehand.

link (url) DOI [BibTex]

link (url) DOI [BibTex]


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Computational mechanisms for the recognition of time sequences of images in the visual cortex

Tan, C., Jhuang, H., Singer, J., Serre, T., Sheinberg, D., Poggio, T.

Society for Neuroscience, 2009 (conference)

pdf [BibTex]

pdf [BibTex]


Thumb xl vriphys2009
Interactive Inverse Kinematics for Monocular Motion Estimation

Morten Engell-Norregaard, Soren Hauberg, Jerome Lapuyade, Kenny Erleben, Kim S. Pedersen

In The 6th Workshop on Virtual Reality Interaction and Physical Simulation (VRIPHYS), 2009 (inproceedings)

Conference site Paper site [BibTex]

Conference site Paper site [BibTex]


Thumb xl thumb screen shot 2012 10 06 at 12.17.40 pm
A Comprehensive Grasp Taxonomy

Feix, T., Pawlik, R., Schmiedmayer, H., Romero, J., Kragic, D.

In Robotics, Science and Systems: Workshop on Understanding the Human Hand for Advancing Robotic Manipulation, 2009 (inproceedings)

Pdf [BibTex]

Pdf [BibTex]


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Population coding of ground truth motion in natural scenes in the early visual system

Stanley, G., Black, M. J., Lewis, J., Desbordes, G., Jin, J., Alonso, J.

COSYNE, 2009 (conference)

[BibTex]

[BibTex]


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Segmentation of Human Upper Airway Using a Level Set Based Deformable Model

Si Yong Yeo, Xianghua Xie, Igor Sazonov, Perumal Nithiarasu

In The 13th Medical Image Understanding and Analysis, 2009 (inproceedings)

[BibTex]

[BibTex]


Thumb xl emmcvpr2009
Three Dimensional Monocular Human Motion Analysis in End-Effector Space

Soren Hauberg, Jerome Lapuyade, Morten Engell-Norregaard, Kenny Erleben, Kim S. Pedersen

In Energy Minimization Methods in Computer Vision and Pattern Recognition, 5681, pages: 235-248, Lecture Notes in Computer Science, (Editors: Cremers, Daniel and Boykov, Yuri and Blake, Andrew and Schmidt, Frank), Springer Berlin Heidelberg, 2009 (inproceedings)

Publishers site Paper site PDF [BibTex]

Publishers site Paper site PDF [BibTex]


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Decoding visual motion from correlated firing of thalamic neurons

Stanley, G. B., Black, M. J., Desbordes, G., Jin, J., Wang, Y., Alonso, J.

2009 Abstract Viewer and Itinerary Planner. Society for Neuroscience, Society for Neuroscience, 2009 (conference)

[BibTex]

[BibTex]

2005


Thumb xl ivc05
Representing cyclic human motion using functional analysis

Ormoneit, D., Black, M. J., Hastie, T., Kjellström, H.

Image and Vision Computing, 23(14):1264-1276, December 2005 (article)

Abstract
We present a robust automatic method for modeling cyclic 3D human motion such as walking using motion-capture data. The pose of the body is represented by a time-series of joint angles which are automatically segmented into a sequence of motion cycles. The mean and the principal components of these cycles are computed using a new algorithm that enforces smooth transitions between the cycles by operating in the Fourier domain. Key to this method is its ability to automatically deal with noise and missing data. A learned walking model is then exploited for Bayesian tracking of 3D human motion.

pdf pdf from publisher DOI [BibTex]

2005

pdf pdf from publisher DOI [BibTex]


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A quantitative evaluation of video-based 3D person tracking

Balan, A. O., Sigal, L., Black, M. J.

In The Second Joint IEEE International Workshop on Visual Surveillance and Performance Evaluation of Tracking and Surveillance, VS-PETS, pages: 349-356, October 2005 (inproceedings)

pdf [BibTex]

pdf [BibTex]


Thumb xl embs05
Inferring attentional state and kinematics from motor cortical firing rates

Wood, F., Prabhat, , Donoghue, J. P., Black, M. J.

In Proc. IEEE Engineering in Medicine and Biology Society, pages: 1544-1547, September 2005 (inproceedings)

pdf [BibTex]

pdf [BibTex]


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Motor cortical decoding using an autoregressive moving average model

Fisher, J., Black, M. J.

In Proc. IEEE Engineering in Medicine and Biology Society, pages: 1469-1472, September 2005 (inproceedings)

pdf [BibTex]

pdf [BibTex]


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Fields of Experts: A framework for learning image priors

Roth, S., Black, M. J.

In IEEE Conf. on Computer Vision and Pattern Recognition, 2, pages: 860-867, June 2005 (inproceedings)

pdf [BibTex]

pdf [BibTex]


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A Flow-Based Approach to Vehicle Detection and Background Mosaicking in Airborne Video

Yalcin, H. C. R. B. M. J. H. M.

IEEE Conf. on Computer Vision and Pattern Recognition (CVPR), Video Proceedings,, pages: 1202, 2005 (patent)

YouTube pdf [BibTex]

YouTube pdf [BibTex]


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On the spatial statistics of optical flow

(Marr Prize, Honorable Mention)

Roth, S., Black, M. J.

In International Conf. on Computer Vision, International Conf. on Computer Vision, pages: 42-49, 2005 (inproceedings)

pdf [BibTex]

pdf [BibTex]


Thumb xl nips05
Modeling neural population spiking activity with Gibbs distributions

Wood, F., Roth, S., Black, M. J.

In Advances in Neural Information Processing Systems 18, pages: 1537-1544, 2005 (inproceedings)

pdf [BibTex]

pdf [BibTex]


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Energy-based models of motor cortical population activity

Wood, F., Black, M.

Program No. 689.20. 2005 Abstract Viewer/Itinerary Planner, Society for Neuroscience, Washington, DC, 2005 (conference)

abstract [BibTex]

abstract [BibTex]

1999


Thumb xl bildschirmfoto 2013 01 14 um 09.07.06
Edges as outliers: Anisotropic smoothing using local image statistics

Black, M. J., Sapiro, G.

In Scale-Space Theories in Computer Vision, Second Int. Conf., Scale-Space ’99, pages: 259-270, LNCS 1682, Springer, Corfu, Greece, September 1999 (inproceedings)

Abstract
Edges are viewed as statistical outliers with respect to local image gradient magnitudes. Within local image regions we compute a robust statistical measure of the gradient variation and use this in an anisotropic diffusion framework to determine a spatially varying "edge-stopping" parameter σ. We show how to determine this parameter for two edge-stopping functions described in the literature (Perona-Malik and the Tukey biweight). Smoothing of the image is related the local texture and in regions of low texture, small gradient values may be treated as edges whereas in regions of high texture, large gradient magnitudes are necessary before an edge is preserved. Intuitively these results have similarities with human perceptual phenomena such as masking and "popout". Results are shown on a variety of standard images.

pdf [BibTex]

1999

pdf [BibTex]


Thumb xl bildschirmfoto 2013 01 07 um 12.35.15
Probabilistic detection and tracking of motion discontinuities

(Marr Prize, Honorable Mention)

Black, M. J., Fleet, D. J.

In Int. Conf. on Computer Vision, ICCV-99, pages: 551-558, ICCV, Corfu, Greece, September 1999 (inproceedings)

pdf [BibTex]

pdf [BibTex]


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Artscience Sciencart

Black, M. J., Levy, D., PamelaZ,

In Art and Innovation: The Xerox PARC Artist-in-Residence Program, pages: 244-300, (Editors: Harris, C.), MIT-Press, 1999 (incollection)

Abstract
One of the effects of the PARC Artist In Residence (PAIR) program has been to expose the strong connections between scientists and artists. Both do what they do because they need to do it. They are often called upon to justify their work in order to be allowed to continue to do it. They need to justify it to funders, to sponsoring institutions, corporations, the government, the public. They publish papers, teach workshops, and write grants touting the educational or health benefits of what they do. All of these things are to some extent valid, but the fact of the matter is: artists and scientists do their work because they are driven to do it. They need to explore and create.

This chapter attempts to give a flavor of one multi-way "PAIRing" between performance artist PamelaZ and two PARC researchers, Michael Black and David Levy. The three of us paired up because we found each other interesting. We chose each other. While most artists in the program are paired with a single researcher Pamela jokingly calls herself a bigamist for choosing two PAIR "husbands" with different backgrounds and interests.

There are no "rules" to the PAIR program; no one told us what to do with our time. Despite this we all had a sense that we needed to produce something tangible during Pamela's year-long residency. In fact, Pamela kept extending her residency because she did not feel as though we had actually made anything concrete. The interesting thing was that all along we were having great conversations, some of which Pamela recorded. What we did not see at the time was that it was these conversations between artists and scientists that are at the heart of the PAIR program and that these conversations were changing the way we thought about our own work and the relationships between science and art.

To give these conversations their due, and to allow the reader into our PAIR interactions, we include two of our many conversations in this chapter.

[BibTex]

[BibTex]


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Parameterized modeling and recognition of activities

Yacoob, Y., Black, M. J.

Computer Vision and Image Understanding, 73(2):232-247, 1999 (article)

Abstract
In this paper we consider a class of human activities—atomic activities—which can be represented as a set of measurements over a finite temporal window (e.g., the motion of human body parts during a walking cycle) and which has a relatively small space of variations in performance. A new approach for modeling and recognition of atomic activities that employs principal component analysis and analytical global transformations is proposed. The modeling of sets of exemplar instances of activities that are similar in duration and involve similar body part motions is achieved by parameterizing their representation using principal component analysis. The recognition of variants of modeled activities is achieved by searching the space of admissible parameterized transformations that these activities can undergo. This formulation iteratively refines the recognition of the class to which the observed activity belongs and the transformation parameters that relate it to the model in its class. We provide several experiments on recognition of articulated and deformable human motions from image motion parameters.

pdf pdf from publisher DOI [BibTex]

pdf pdf from publisher DOI [BibTex]


Thumb xl bildschirmfoto 2013 01 14 um 09.12.47
Explaining optical flow events with parameterized spatio-temporal models

Black, M. J.

In IEEE Proc. Computer Vision and Pattern Recognition, CVPR’99, pages: 326-332, IEEE, Fort Collins, CO, 1999 (inproceedings)

pdf video [BibTex]

pdf video [BibTex]

1997


Thumb xl sharpening
Robust anisotropic diffusion and sharpening of scalar and vector images

Black, M. J., Sapiro, G., Marimont, D., Heeger, D.

In Int. Conf. on Image Processing, ICIP, 1, pages: 263-266, Vol. 1, Santa Barbara, CA, October 1997 (inproceedings)

Abstract
Relations between anisotropic diffusion and robust statistics are described. We show that anisotropic diffusion can be seen as a robust estimation procedure that estimates a piecewise smooth image from a noisy input image. The "edge-stopping" function in the anisotropic diffusion equation is closely related to the error norm and influence function in the robust estimation framework. This connection leads to a new "edge-stopping" function based on Tukey's biweight robust estimator, that preserves sharper boundaries than previous formulations and improves the automatic stopping of the diffusion. The robust statistical interpretation also provides a means for detecting the boundaries (edges) between the piecewise smooth regions in the image. We extend the framework to vector-valued images and show applications to robust image sharpening.

pdf publisher site [BibTex]

1997

pdf publisher site [BibTex]


Thumb xl bildschirmfoto 2013 01 14 um 10.31.38
Robust anisotropic diffusion: Connections between robust statistics, line processing, and anisotropic diffusion

Black, M. J., Sapiro, G., Marimont, D., Heeger, D.

In Scale-Space Theory in Computer Vision, Scale-Space’97, pages: 323-326, LNCS 1252, Springer Verlag, Utrecht, the Netherlands, July 1997 (inproceedings)

pdf [BibTex]

pdf [BibTex]


Thumb xl bildschirmfoto 2013 01 14 um 10.05.56
Learning parameterized models of image motion

Black, M. J., Yacoob, Y., Jepson, A. D., Fleet, D. J.

In IEEE Conf. on Computer Vision and Pattern Recognition, CVPR-97, pages: 561-567, Puerto Rico, June 1997 (inproceedings)

Abstract
A framework for learning parameterized models of optical flow from image sequences is presented. A class of motions is represented by a set of orthogonal basis flow fields that are computed from a training set using principal component analysis. Many complex image motions can be represented by a linear combination of a small number of these basis flows. The learned motion models may be used for optical flow estimation and for model-based recognition. For optical flow estimation we describe a robust, multi-resolution scheme for directly computing the parameters of the learned flow models from image derivatives. As examples we consider learning motion discontinuities, non-rigid motion of human mouths, and articulated human motion.

pdf [BibTex]

pdf [BibTex]


Thumb xl bildschirmfoto 2013 01 14 um 10.13.51
Analysis of gesture and action in technical talks for video indexing

Ju, S. X., Black, M. J., Minneman, S., Kimber, D.

In IEEE Conf. on Computer Vision and Pattern Recognition, pages: 595-601, CVPR-97, Puerto Rico, June 1997 (inproceedings)

Abstract
In this paper, we present an automatic system for analyzing and annotating video sequences of technical talks. Our method uses a robust motion estimation technique to detect key frames and segment the video sequence into subsequences containing a single overhead slide. The subsequences are stabilized to remove motion that occurs when the speaker adjusts their slides. Any changes remaining between frames in the stabilized sequences may be due to speaker gestures such as pointing or writing and we use active contours to automatically track these potential gestures. Given the constrained domain we define a simple ``vocabulary'' of actions which can easily be recognized based on the active contour shape and motion. The recognized actions provide a rich annotation of the sequence that can be used to access a condensed version of the talk from a web page.

pdf [BibTex]

pdf [BibTex]


Thumb xl bildschirmfoto 2013 01 14 um 10.36.36
Modeling appearance change in image sequences

Black, M. J., Yacoob, Y., Fleet, D. J.

In Advances in Visual Form Analysis, pages: 11-20, Proceedings of the Third International Workshop on Visual Form, Capri, Italy, May 1997 (inproceedings)

abstract [BibTex]

abstract [BibTex]


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Recognizing facial expressions in image sequences using local parameterized models of image motion

Black, M. J., Yacoob, Y.

Int. Journal of Computer Vision, 25(1):23-48, 1997 (article)

Abstract
This paper explores the use of local parametrized models of image motion for recovering and recognizing the non-rigid and articulated motion of human faces. Parametric flow models (for example affine) are popular for estimating motion in rigid scenes. We observe that within local regions in space and time, such models not only accurately model non-rigid facial motions but also provide a concise description of the motion in terms of a small number of parameters. These parameters are intuitively related to the motion of facial features during facial expressions and we show how expressions such as anger, happiness, surprise, fear, disgust, and sadness can be recognized from the local parametric motions in the presence of significant head motion. The motion tracking and expression recognition approach performed with high accuracy in extensive laboratory experiments involving 40 subjects as well as in television and movie sequences.

pdf pdf from publisher abstract video [BibTex]


Thumb xl bildschirmfoto 2013 01 15 um 11.00.33
Recognizing human motion using parameterized models of optical flow

Black, M. J., Yacoob, Y., Ju, X. S.

In Motion-Based Recognition, pages: 245-269, (Editors: Mubarak Shah and Ramesh Jain,), Kluwer Academic Publishers, Boston, MA, 1997 (incollection)

pdf [BibTex]

pdf [BibTex]