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Efficient Modelling and Synthesis of Data Intensive Reconfigurable Systems

Andersson, Per LU (2005)
Abstract
Digital systems are integrated in our environment and have become a natural part of our every day life. As we rely more on these systems our expectations on them increases. We expect them to perform new tasks, communicate and cooperate. The complexity of these systems are increasing. The increasing complexity and the requirement for flexibility, which allows the system to adapt and evolve over time, makes them difficult to design and realise using existing techniques and tools. This thesis address different problems in the design process of flexible digital systems.



We present our computational model Image Processing-Data Flow Graphs (IP-DFG), a computational model tailored for modelling and implementation of image... (More)
Digital systems are integrated in our environment and have become a natural part of our every day life. As we rely more on these systems our expectations on them increases. We expect them to perform new tasks, communicate and cooperate. The complexity of these systems are increasing. The increasing complexity and the requirement for flexibility, which allows the system to adapt and evolve over time, makes them difficult to design and realise using existing techniques and tools. This thesis address different problems in the design process of flexible digital systems.



We present our computational model Image Processing-Data Flow Graphs (IP-DFG), a computational model tailored for modelling and implementation of image processing algorithms. IP-DFG is based on Data Flow Graphs (DFGs), which have been extended with hierarchy and explicit support for loops. This allows for a natural representation of image processing tasks.



The computational model IP-DFG have been integrated into our run-time system IPAPI. IPAPI manages the execution of all image processing related tasks in our Unmanned Aerial Vehicle (UAV) in the WITAS project. Combining a Java implementation of IPAPI and a library of highly optimised implementations of a few key IP-DFG nodes gives high flexibility and sufficient performance. The flexibility greatly simplified the process of migrating the functionality from a simulated system on desktop computers to the on-board system of the UAV.



Hardware acceleration have successfully been used to increase the performance in many applications. We discuss different trade-offs during the design process of hardware accelerated systems and present our hardware software interface. We also suggests a design flow for rapid prototyping of System on Programmable Chips (SoPCs).



One part of the design flow is automatic hardware compilation from Java. Our hardware compiler takes a new approach to hardware compilation. The source code is partitioned based on its behaviour and characteristics. Each partitioned is treated separately, allowing domain specific optimisations and code generators to be used.



Our work with hardware compilation have been focused on memory accesses. We use data dependence analysis to detect data reuse. Data to be reduced are stored in local memories close to the data path. This drastically reduce the number of accesses to the data being processed, allowing large data structures to be stored in cost efficient but slow external memory while still running the data path at full speed. (Less)
Please use this url to cite or link to this publication:
author
supervisor
opponent
  • Professor Wolinski, Christophe, University of Rennes, France
organization
publishing date
type
Thesis
publication status
published
subject
keywords
kontroll, Systems engineering, numerisk analys, system, control, Datalogi, numerical analysis, systems, Data Flow Graphs, Data Flow Modlling, computer technology, Data- och systemvetenskap, Computer science, Hardware Compilation, Synthesis
pages
144 pages
publisher
Department of Computer Science, Lund University
defense location
Room E:1406, E-building, Lund Institute of Technology
defense date
2005-06-17 13:15
ISSN
1404-1219
ISBN
91-628-6556-0
language
English
LU publication?
yes
id
12fc8dfb-fc4f-4f0e-9450-e705db1e7550 (old id 545134)
date added to LUP
2007-10-13 11:46:29
date last changed
2016-09-19 08:44:53
@phdthesis{12fc8dfb-fc4f-4f0e-9450-e705db1e7550,
  abstract     = {Digital systems are integrated in our environment and have become a natural part of our every day life. As we rely more on these systems our expectations on them increases. We expect them to perform new tasks, communicate and cooperate. The complexity of these systems are increasing. The increasing complexity and the requirement for flexibility, which allows the system to adapt and evolve over time, makes them difficult to design and realise using existing techniques and tools. This thesis address different problems in the design process of flexible digital systems.<br/><br>
<br/><br>
We present our computational model Image Processing-Data Flow Graphs (IP-DFG), a computational model tailored for modelling and implementation of image processing algorithms. IP-DFG is based on Data Flow Graphs (DFGs), which have been extended with hierarchy and explicit support for loops. This allows for a natural representation of image processing tasks.<br/><br>
<br/><br>
The computational model IP-DFG have been integrated into our run-time system IPAPI. IPAPI manages the execution of all image processing related tasks in our Unmanned Aerial Vehicle (UAV) in the WITAS project. Combining a Java implementation of IPAPI and a library of highly optimised implementations of a few key IP-DFG nodes gives high flexibility and sufficient performance. The flexibility greatly simplified the process of migrating the functionality from a simulated system on desktop computers to the on-board system of the UAV.<br/><br>
<br/><br>
Hardware acceleration have successfully been used to increase the performance in many applications. We discuss different trade-offs during the design process of hardware accelerated systems and present our hardware software interface. We also suggests a design flow for rapid prototyping of System on Programmable Chips (SoPCs).<br/><br>
<br/><br>
One part of the design flow is automatic hardware compilation from Java. Our hardware compiler takes a new approach to hardware compilation. The source code is partitioned based on its behaviour and characteristics. Each partitioned is treated separately, allowing domain specific optimisations and code generators to be used.<br/><br>
<br/><br>
Our work with hardware compilation have been focused on memory accesses. We use data dependence analysis to detect data reuse. Data to be reduced are stored in local memories close to the data path. This drastically reduce the number of accesses to the data being processed, allowing large data structures to be stored in cost efficient but slow external memory while still running the data path at full speed.},
  author       = {Andersson, Per},
  isbn         = {91-628-6556-0},
  issn         = {1404-1219},
  keyword      = {kontroll,Systems engineering,numerisk analys,system,control,Datalogi,numerical analysis,systems,Data Flow Graphs,Data Flow Modlling,computer technology,Data- och systemvetenskap,Computer science,Hardware Compilation,Synthesis},
  language     = {eng},
  pages        = {144},
  publisher    = {Department of Computer Science, Lund University},
  school       = {Lund University},
  title        = {Efficient Modelling and Synthesis of Data Intensive Reconfigurable Systems},
  year         = {2005},
}