Task parallelism for ray tracing on a gpu cluster

Ünlü, Çağlar
Ray tracing is a computationally complex global illumination algorithm that is used for producing realistic images. In addition to parallel implementations on commodity PC clusters, recently, Graphics Processing Units (GPU) have also been used to accelerate ray tracing. In this thesis, ray tracing is accelerated on a GPU cluster where the viewing plane is divided into unit tiles. Slave processes work on these tiles in a task parallel manner which are dynamically assigned to them. To decrease the number of ray-triangle intersection tests, Bounding Volume Hierarchies (BVH) are used. It is shown that almost linear speedup can be achieved. On the other hand, it is observed that API and network overheads are obstacles for scalability.


Efficient algorithms for convolutional inverse problems in multidimensional imaging
Doğan, Didem; Öktem, Figen S.; Department of Electrical and Electronics Engineering (2020)
Computational imaging is the process of indirectly forming images from measurements using image reconstruction algorithms that solve inverse problems. In many inverse problems in multidimensional imaging such as spectral and depth imaging, the measurements are in the form of superimposed convolutions related to the unknown image. In this thesis, we first provide a general formulation for these problems named as convolutional inverse problems, and then develop fast and efficient image reconstruction algorith...
Smoothing and differentiation of dynamic data
Titrek, Fatih; Tarı, Zehra Sibel; Department of Computer Engineering (2010)
Smoothing is an important part of the pre-processing step in Signal Processing. A signal, which is purified from noise as much as possible, is necessary to achieve our aim. There are many smoothing algorithms which give good result on a stationary data, but these smoothing algorithms don’t give expected result in a non-stationary data. Studying Acceleration data is an effective method to see whether the smoothing is successful or not. The small part of the noise that takes place in the Displacement data wil...
Error analysis and testing of DRM for frame cameras
Bettemir, Oe. H.; Karslıoğlu, Mahmut Onur; Friedrich, J. (2007-06-16)
A new Differential Rectification Method (DRM) for frame cameras is proposed by Karslioglu and Friedrich [1] for the generation of orthoimages from monoscopic digital images which map every pixel onto a curved surface of reference frame i.e. WGS84. The ellipsoidal geodetic coordinates, of each pixel are calculated directly under the condition that a precise enough elevation model is available avoiding additional earth curvature corrections after the rectification. In this paper, convergence of the differenti...
Interactive editing of complex terrains on parallel graphics architectures
Gün, Ufuk; İşler, Veysi; Department of Computer Engineering (2009)
Rendering large terrains on large screens at interactive frame rates is a challenging area of computer graphics. In the last decade, real-time terrain rendering on large screens played a significant role in various simulations and virtual reality systems. To fulfill the demand of these systems, two software tools are developed. The first tool is a Terrain Editor that creates and manipulates large terrains. The second is a Multi-Display Viewer that displays the created terrains on multiple screens. Since the...
Image fusion for improving spatial resolution of multispectral satellite images
Ünlüsoy, Deniz; Süzen, Mehmet Lütfi; Department of Geological Engineering (2013)
In this study, four different image fusion techniques have been applied to high spectral and low spatial resolution satellite images with high spatial and low spectral resolution images to obtain fused images with increased spatial resolution, while preserving spectral information as much as possible. These techniques are intensity-hue-saturation (IHS) transform, principle component analysis (PCA), Brovey transform (BT), and Wavelet transform (WT) image fusion. Images used in the study belong to Çankırı reg...
Citation Formats
Ç. Ünlü, “Task parallelism for ray tracing on a gpu cluster,” M.S. - Master of Science, Middle East Technical University, 2008.