Sökning: "Sparse representation"

Visar resultat 1 - 5 av 47 avhandlingar innehållade orden Sparse representation.

1. 1. Sparse Modeling of Harmonic Signals

   Författare :Filip Elvander; Statistical Signal Processing Group; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; NATURVETENSKAP; NATURAL SCIENCES; multi-pitch estimation; sparse modeling; convex optimisation; inharmonicity; sparse recursive least squares; adaptive signal processing; optimal transport distance;

   Sammanfattning : This thesis considers sparse modeling and estimation of multi-pitch signals, i.e., signals whose frequency content can be described by superpositions of harmonic, or close-to-harmonic, structures, characterized by a set of fundamental frequencies. LÄS MER

3. 2. Sparse Voxel DAGs

   Författare :Viktor Kämpe; Chalmers tekniska högskola; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Geometry; Shadows; Data structures; Tree; Visibility; Grid; Voxel; Directed acyclic graph; Computer graphics;

   Sammanfattning : This thesis investigates a memory-efficient representation of highly detailed geometry in 3D voxel grids. The memory consumption of a plain dense grid scales too fast as the resolution increases to be feasible at very high resolutions. LÄS MER

4. 3. Data-Driven Approaches for Sparse Reflectance Modeling and Acquisition

   Författare :Tanaboon Tongbuasirilai; Jonas Unger; Ehsan Miandji; Jakob Wenzel; Linköpings universitet; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; BRDF; Reflectance modeling; Sparse representation; Compressed sensing; Factorization;

   Sammanfattning : Photo-realistic rendering and predictive image synthesis are becoming increasingly important and utilized in many application areas ranging from production of visual effects and product visualization to digital design and the generation of synthetic data for visual machine learning applications. Many essential components of the realistic image synthesis pipelines have been developed tremendously over the last decades. LÄS MER

5. 4. Sparse Matrices in Self-Consistent Field Methods

   Författare :Emanuel Rubensson; Pawel Salek; Hans Ågren; Anders Niklasson; Axel Ruhe; KTH; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; sparse matrix; self-consistent field; Hartree-Fock; Density Functional Theory; Density Matrix Purification; Theoretical chemistry; Teoretisk kemi;

   Sammanfattning : This thesis is part of an effort to enable large-scale Hartree-Fock/Kohn-Sham (HF/KS) calculations. The objective is to model molecules and materials containing thousands of atoms at the quantum mechanical level. HF/KS calculations are usually performed with the Self-Consistent Field (SCF) method. LÄS MER

7. 5. Sparse representation of visual data for compression and compressed sensing

   Författare :Ehsan Miandji; Jonas Unger; Anders Ynnerman; Hendrik P. A. Lensch; Linköpings universitet; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY;

   Sammanfattning : The ongoing advances in computational photography have introduced a range of new imaging techniques for capturing multidimensional visual data such as light fields, BRDFs, BTFs, and more. A key challenge inherent to such imaging techniques is the large amount of high dimensional visual data that is produced, often requiring GBs, or even TBs, of storage. LÄS MER