Efficient Image-Space Data Reuse in Rendering and Image Processing

The Hong Kong University of Science and Technology
Department of Computer Science and Engineering


PhD Thesis Defence


Title: "Efficient Image-Space Data Reuse in Rendering and Image Processing"

By

Mr. Lei Yang


Abstract

Spatio-temporal coherence and data reuse are important problems in digital 
image synthesis and processing. The existence of coherence, i.e. local data 
similarity, usually leads to redundancy of data and computations in virtually 
every stage of the pipeline. By exploiting such coherence, we can potentially 
reduce a large amount of unnecessary computations. This not only has the 
benefit of accelerating the process, but also provides opportunities to improve 
the result quality with the additional data that are not available otherwise.

In this thesis, we introduce techniques for spatial and temporal data reuse 
that benefit a number of real-time rendering and image-processing applications. 
For simplicity and efficiency, we explore methods that operate in image space. 
Moreover, for all the applications, we seek to design parallel real-time 
algorithms that executes on the GPU or multi-core CPU. This may limit the class 
of techniques that we can use, but the high efficiency can benefit a much wider 
range of high-performance graphics applications.

For spatial data reuse, we first show how the results of interpolating sparse 
shading data on an image can be improved with an edge-preserving filter. We 
then introduce a sampling scheme that accelerates the costly computation of 
diffuse indirect illumination by allowing spatial data share. Moreover, in the 
field of image processing, we demonstrate how data in coherent regions can be 
reused to fix antialiased edges that are damaged by non-linear filters. For 
temporal data reuse, we introduce a few techniques and tools for improving the 
performance of data reprojection -- a fundamental operation for temporal data 
reuse. We then propose a technique for effectively amortizing the computation 
of super sampling over time. This comes with a principled analysis of the 
quality associated with repeated reprojection. Finally, we show an efficient 
frame-interpolation technique that significantly improves framerate for general 
real-time rendering applications.


Date:			Thursday, 28 July 2011

Time:			2:00pm – 4:00pm

Venue:			Room 3588
 			Lifts 27/28

Chairman:		Prof. Oscar Au (ECE)

Committee Members:	Prof. Pedro Sander (Supervisor)
 			Prof. Siu-Wing Cheng
 			Prof. Long Quan
                         Prof. Ajay Joneja (IELM)
                         Prof. Jiaya Jia (Comp. Sci. & Engg., CUHK)


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