Atanas Gotchev - Academia.edu (original) (raw)

Papers by Atanas Gotchev

Research paper thumbnail of Recurrent Neural Networks For Modeling Motion Capture Data

Publication in the conference proceedings of Deep Learning and Geometry, Kos island, Greece, 2017

Research paper thumbnail of Intensity-based pointwise processing in dynamic laser speckle analysis

2015 11th Conference on Lasers and Electro-Optics Pacific Rim (CLEO-PR), 2015

Research paper thumbnail of Real-time depth image-based rendering with layered dis-occlusion compensation and aliasing-free composition

Image Processing: Algorithms and Systems XIII, 2015

Research paper thumbnail of Computer technologies for 3D video delivery for home entertainment

Proceedings of the 9th International Conference on Computer Systems and Technologies and Workshop for PhD Students in Computing - CompSysTech '08, 2008

... 17, No. 11, pp. 1568-1586, 2007. [5] E. İmre, S. Knorr, B. Özkalaycı, U. Topay, A. Alatan, T.... more ... 17, No. 11, pp. 1568-1586, 2007. [5] E. İmre, S. Knorr, B. Özkalaycı, U. Topay, A. Alatan, T. Sikora, Towards 3-D Scene Reconstruction from Broadcast Video, Signal Processing: Image Communication 22, pp 108-126, 2007. ...

Research paper thumbnail of Super resolution inverse imaging for plenoptic camera using wavefield modeling

2014 3DTV-Conference: The True Vision - Capture, Transmission and Display of 3D Video (3DTV-CON), 2014

ABSTRACT A plenoptic camera consists of microlenses that enable the measuring of directional info... more ABSTRACT A plenoptic camera consists of microlenses that enable the measuring of directional information. A common image formation model of the plenoptic camera is based on geometrical optics and provides an object reconstruction with a resolution equal to the number of microlenses. We use a more accurate model that takes into account the wave properties of light. A discrete formulation of this model is done in order to develop the inverse imaging technique which is efficient for super resolution object reconstruction even from noisy data. The proposed algorithm is based on a special modification of the IDD-BM3D deblurring algorithm. The achieved resolution highly exceeds the number of microlenses which is what we call super resolution imaging. Simulations show that the proposed strategy essentially outperforms the previously suggested method based on the wavefield modeling.

Research paper thumbnail of A multiresolution approach to closed glottis interval determination

2000 10th European Signal Processing Conference, Sep 1, 2000

Research paper thumbnail of A near least squares method for image decimation

Proceedings 2003 International Conference on Image Processing, Oct 17, 2003

ABSTRACT This paper introduces an image,decimation technique based on the use of a ,near least-sq... more ABSTRACT This paper introduces an image,decimation technique based on the use of a ,near least-squares criterion that makes ,a proper compromise,between ,the L2 and ,l2 norm ,minimization ,cases. The theory of orthogonal,projections is related to the derivation ofa,computationally ,efficient decimation ,structure possessing good anti-aliasing properties. It is shown,how,this structure can berealized,by the ,transposed Farrow structure when ,using piece-wise polynomial basis

Research paper thumbnail of Validation of a new full reference metric for quality assessment of mobile 3DTV content

2011 19th European Signal Processing Conference, Aug 1, 2011

ABSTRACT 3D video is expected to provide an enhanced user experience bringing more realism throug... more ABSTRACT 3D video is expected to provide an enhanced user experience bringing more realism through depth impression. Therefore, quality assessment plays an important role when designing and optimizing 3D video processing methods and applications. In this ...

Research paper thumbnail of Relative importance of depth cues on portable autostereoscopic display

Proceedings of the 3rd Workshop, Oct 25, 2010

ABSTRACT Depth of a three-dimensional scene is perceived using sev-eral different visual cues. Th... more ABSTRACT Depth of a three-dimensional scene is perceived using sev-eral different visual cues. The process of perceiving depth is delicate and vulnerable to artefacts. On autostereoscopic displays the aim is to enhance the sensation of reality of the experience by the added ...

Research paper thumbnail of ECG signal denoising using wavelet domain wiener filtering

2000 10th European Signal Processing Conference, Sep 1, 2000

ABSTRACT A two-stage algorithm for suppression of electromyogram (EMG) artifacts from the electro... more ABSTRACT A two-stage algorithm for suppression of electromyogram (EMG) artifacts from the electrocardiogram (ECG) using Wavelet Domain Wiener Filtering has been investigated. An improvement of the traditional technique is proposed by involving Time-frequency ...

Research paper thumbnail of Phase Shifting in the Quincunx Filter Bank

Research paper thumbnail of Apparatus, a Method and a Computer Program for Image Processing

Research paper thumbnail of Multi-Frame Image Calibrator

Research paper thumbnail of Measurement of perceived spatial resolution in 3D light-field displays

2014 Ieee International Conference on Image Processing, Oct 1, 2014

Research paper thumbnail of Efficient Super-Resolution Reconstruction for Translational Motion using a Near Least Squares Resampling Method

Proceedings Icip International Conference on Image Processing, Oct 1, 2006

In this paper we propose a computationally efficient method for image super-resolution reconstruc... more In this paper we propose a computationally efficient method for image super-resolution reconstruction. We concentrate on pure translational motion and shift-invariant blur. This is the case of interlaced sampling where each low resolution image is uniformly sampled but the overall sampling is non- uniform with respect to the high resolution grid. The reconstruction problem is considered in a multi-resolution framework using separable B-spline wavelets as basis. This allows performing the reconstruction on a uniform higher resolution grid by digital filtering. A computationally efficient structure - the transposed modified Farrow structure is used to achieve a near least squares solution without using any matrix inversions or iterations. The reconstruction can also be performed at non-dyadic scales. Our method minimizes the aliasing distortions and gives results comparable with other least squares techniques. Index Terms— Super-resolution, interlaced sampling, near least squares resampling, Transposed Farrow structure.

Research paper thumbnail of On the performance of multirate filterbanks: Quantification of shift variance and cyclostationarity in the works of Til Aach

ABSTRACT The paper discusses the issues of shift variance and cyclostationarity in multirate filt... more ABSTRACT The paper discusses the issues of shift variance and cyclostationarity in multirate filterbanks as investigated in a series of articles by Til Aach. In its first part, the paper overviews the most important properties of multirate filterbanks such as perfect reconstruction, sampling rate conversion factors, number and type of subbands and subdivisions, orthogonality and bio-orthogonality, and frequency selectivity and preservation of polynomials. This part in intended introduce the reader to the topic and make a bridge to the properties of shift variance and cyclostationarity discussed next. Criteria for shift (in)variance and cyclostationarity as derived by Til Aach are presented and commented and conclusions about their importance are made.

Research paper thumbnail of Methodology for design of antialiasing filters for autostereoscopic displays (Advanced techniques on multirate signal processing for digital information processing)

Signal Processing Iet, Jun 1, 2011

Research paper thumbnail of Classification of stereoscopic artefacts

Research paper thumbnail of Comparing the Performance of Optimized Piece-Wise Polynomial Image Interpolators

Research paper thumbnail of Efficient motion estimation utilizing quadrature filters

Research paper thumbnail of Recurrent Neural Networks For Modeling Motion Capture Data

Publication in the conference proceedings of Deep Learning and Geometry, Kos island, Greece, 2017

Research paper thumbnail of Intensity-based pointwise processing in dynamic laser speckle analysis

2015 11th Conference on Lasers and Electro-Optics Pacific Rim (CLEO-PR), 2015

Research paper thumbnail of Real-time depth image-based rendering with layered dis-occlusion compensation and aliasing-free composition

Image Processing: Algorithms and Systems XIII, 2015

Research paper thumbnail of Computer technologies for 3D video delivery for home entertainment

Proceedings of the 9th International Conference on Computer Systems and Technologies and Workshop for PhD Students in Computing - CompSysTech '08, 2008

... 17, No. 11, pp. 1568-1586, 2007. [5] E. İmre, S. Knorr, B. Özkalaycı, U. Topay, A. Alatan, T.... more ... 17, No. 11, pp. 1568-1586, 2007. [5] E. İmre, S. Knorr, B. Özkalaycı, U. Topay, A. Alatan, T. Sikora, Towards 3-D Scene Reconstruction from Broadcast Video, Signal Processing: Image Communication 22, pp 108-126, 2007. ...

Research paper thumbnail of Super resolution inverse imaging for plenoptic camera using wavefield modeling

2014 3DTV-Conference: The True Vision - Capture, Transmission and Display of 3D Video (3DTV-CON), 2014

ABSTRACT A plenoptic camera consists of microlenses that enable the measuring of directional info... more ABSTRACT A plenoptic camera consists of microlenses that enable the measuring of directional information. A common image formation model of the plenoptic camera is based on geometrical optics and provides an object reconstruction with a resolution equal to the number of microlenses. We use a more accurate model that takes into account the wave properties of light. A discrete formulation of this model is done in order to develop the inverse imaging technique which is efficient for super resolution object reconstruction even from noisy data. The proposed algorithm is based on a special modification of the IDD-BM3D deblurring algorithm. The achieved resolution highly exceeds the number of microlenses which is what we call super resolution imaging. Simulations show that the proposed strategy essentially outperforms the previously suggested method based on the wavefield modeling.

Research paper thumbnail of A multiresolution approach to closed glottis interval determination

2000 10th European Signal Processing Conference, Sep 1, 2000

Research paper thumbnail of A near least squares method for image decimation

Proceedings 2003 International Conference on Image Processing, Oct 17, 2003

ABSTRACT This paper introduces an image,decimation technique based on the use of a ,near least-sq... more ABSTRACT This paper introduces an image,decimation technique based on the use of a ,near least-squares criterion that makes ,a proper compromise,between ,the L2 and ,l2 norm ,minimization ,cases. The theory of orthogonal,projections is related to the derivation ofa,computationally ,efficient decimation ,structure possessing good anti-aliasing properties. It is shown,how,this structure can berealized,by the ,transposed Farrow structure when ,using piece-wise polynomial basis

Research paper thumbnail of Validation of a new full reference metric for quality assessment of mobile 3DTV content

2011 19th European Signal Processing Conference, Aug 1, 2011

ABSTRACT 3D video is expected to provide an enhanced user experience bringing more realism throug... more ABSTRACT 3D video is expected to provide an enhanced user experience bringing more realism through depth impression. Therefore, quality assessment plays an important role when designing and optimizing 3D video processing methods and applications. In this ...

Research paper thumbnail of Relative importance of depth cues on portable autostereoscopic display

Proceedings of the 3rd Workshop, Oct 25, 2010

ABSTRACT Depth of a three-dimensional scene is perceived using sev-eral different visual cues. Th... more ABSTRACT Depth of a three-dimensional scene is perceived using sev-eral different visual cues. The process of perceiving depth is delicate and vulnerable to artefacts. On autostereoscopic displays the aim is to enhance the sensation of reality of the experience by the added ...

Research paper thumbnail of ECG signal denoising using wavelet domain wiener filtering

2000 10th European Signal Processing Conference, Sep 1, 2000

ABSTRACT A two-stage algorithm for suppression of electromyogram (EMG) artifacts from the electro... more ABSTRACT A two-stage algorithm for suppression of electromyogram (EMG) artifacts from the electrocardiogram (ECG) using Wavelet Domain Wiener Filtering has been investigated. An improvement of the traditional technique is proposed by involving Time-frequency ...

Research paper thumbnail of Phase Shifting in the Quincunx Filter Bank

Research paper thumbnail of Apparatus, a Method and a Computer Program for Image Processing

Research paper thumbnail of Multi-Frame Image Calibrator

Research paper thumbnail of Measurement of perceived spatial resolution in 3D light-field displays

2014 Ieee International Conference on Image Processing, Oct 1, 2014

Research paper thumbnail of Efficient Super-Resolution Reconstruction for Translational Motion using a Near Least Squares Resampling Method

Proceedings Icip International Conference on Image Processing, Oct 1, 2006

In this paper we propose a computationally efficient method for image super-resolution reconstruc... more In this paper we propose a computationally efficient method for image super-resolution reconstruction. We concentrate on pure translational motion and shift-invariant blur. This is the case of interlaced sampling where each low resolution image is uniformly sampled but the overall sampling is non- uniform with respect to the high resolution grid. The reconstruction problem is considered in a multi-resolution framework using separable B-spline wavelets as basis. This allows performing the reconstruction on a uniform higher resolution grid by digital filtering. A computationally efficient structure - the transposed modified Farrow structure is used to achieve a near least squares solution without using any matrix inversions or iterations. The reconstruction can also be performed at non-dyadic scales. Our method minimizes the aliasing distortions and gives results comparable with other least squares techniques. Index Terms— Super-resolution, interlaced sampling, near least squares resampling, Transposed Farrow structure.

Research paper thumbnail of On the performance of multirate filterbanks: Quantification of shift variance and cyclostationarity in the works of Til Aach

ABSTRACT The paper discusses the issues of shift variance and cyclostationarity in multirate filt... more ABSTRACT The paper discusses the issues of shift variance and cyclostationarity in multirate filterbanks as investigated in a series of articles by Til Aach. In its first part, the paper overviews the most important properties of multirate filterbanks such as perfect reconstruction, sampling rate conversion factors, number and type of subbands and subdivisions, orthogonality and bio-orthogonality, and frequency selectivity and preservation of polynomials. This part in intended introduce the reader to the topic and make a bridge to the properties of shift variance and cyclostationarity discussed next. Criteria for shift (in)variance and cyclostationarity as derived by Til Aach are presented and commented and conclusions about their importance are made.

Research paper thumbnail of Methodology for design of antialiasing filters for autostereoscopic displays (Advanced techniques on multirate signal processing for digital information processing)

Signal Processing Iet, Jun 1, 2011

Research paper thumbnail of Classification of stereoscopic artefacts

Research paper thumbnail of Comparing the Performance of Optimized Piece-Wise Polynomial Image Interpolators

Research paper thumbnail of Efficient motion estimation utilizing quadrature filters