10610312
Semantic sports video analysis: approaches and new applications
In this paper, we show that event-based semantic analysis of sports video can be achieved through two major classes of methods: approaches using deterministic reasoning and approaches depending on probabilistic inference. Deterministic approaches depend on an explicit description of an event and an explicit representation of the event in terms of low-level aural-visual features that can be automatically detected. Probabilistic approaches are based on some proper state/transition models whose parameters are learnt through labeled training sequences. We first discuss the pros and cons of the two classes of approaches. Next, we present algorithms of these two types for a new application, automatic analysis of coaching video (which is different from sports broadcast programs that have been subject of most prior work).
16949052
Automatic keystone correction for smart projectors with embedded camera
We propose embedded algorithms for enabling a smart self-adjusting projector that is capable of fully automatic keystone distortion detection and correction, plus zooming and centering the image to fit a screen. The projector has an embedded camera and it automatically detects the screen and a specific pattern during self-adjustment. Proposed algorithms meet severe computational requirements of a portable projector and they exploit the physical constraints in a projector-(embedded) camera pair in a novel way in order to not compromise image quality under different usage conditions. We will demonstrate our projector system during the conference.
11775748
Schema Mapping for Interoperability in XML-based multidatabase
The main aim of a multidatabase system (MDBS) is to achieve data integration and interoperability among distributed and heterogeneous database systems. But data model heterogeneity and schema make this a challenging task. Multidatabase users can only view the global schemas whose real data come from local database systems. Thus, mappings from global schemas to local schemas should be established. At the same time, the recent emergence of XML has shown great intractability as a new standard for data representation and exchange on the Web. A data model based on XML becomes more suitable for integrating different types of systems. This paper firstly introduces a multidatabase common data model based on XML, named XML-based Integration Model (XIDM). Then, an approach of schema mappings based on XIDM in MDBSs has been presented. Finally, the illustration and implementation of schema mappings in a multidatabase prototype - Panorama are also discussed.
3592974
Code Compaction of Matching Single-Entry Multiple-Exit Regions
With the proliferation of embedded devices and systems, there is renewed interest in the generation of compact binaries. Code compaction techniques identify code sequences that repeatedly appear in a program and replace them by a single copy of the recurring sequence. In existing techniques such sequences are typically restricted to single-entry single-exit regions in the control flow graph. We have observed that in many applications recurring code sequences form single-entry multipleexit (SEME) regions. In this paper we propose a generalized algorithm for code compaction that first decomposes a control flow graph into a hierarchy of SEME regions, computes signatures of SEME regions, and then uses the signatures to find pairs of matching SEME regions. Maximal sized matching SEME regions are found and transformed to achieve code compaction. Our transformation is able to compact matching SEME regions whose exits may lead to a combination of identical and differing targets. Our experiments show that this transformation can lead to substantial reduction in code size for many embedded applications.
12309193
Building a Chinese Shallow Parsed TreeBank for Collocation Extraction
To automatically extract Chinese collocations and build a large-scale collocation bank, we are developing a one-million-word Chinese shallow parsed treebank. The treebank can be used not only as a training set for our shallow parser, but also as processed data from which collocations are extracted. This paper presents several issues related to this on-going project, such as our definition of shallow parsing used in Chinese collocation extraction, guideline preparation, and quality control.
3580064
Bit section instruction set extension of ARM for embedded applications
Programs that manipulate data at subword level, i.e. bit sections within a word, are common place in the embedded domain. Examples of such applications include media processing as well as network processing codes. These applications spend significant amounts of time packing and unpacking narrow width data into memory words. The execution time and memory overhead of packing and unpacking operations can be greatly reduced by providing direct instruction set support for manipulating bit sections.In this paper we present the Bit Section eXtension (BSX) to the ARM instruction set. We selected the ARM processor for this research because it is one of the most popular embedded processor which is also being used as the basis of building many commercial network processing architectures. We present the design of BSX instructions and their encoding into the ARM instruction set. We have incorporated the implementation of BSX into the Simplescalar ARM simulator from Michigan. Results of experiments with programs from various benchmark suites show that by using BSX instructions the total number of instructions executed at runtime by many transformed functions are reduced by 4.26% to 27.27% and their code sizes are reduced by `1.27% to 21.05%.
3584727
Simple offset assignment in presence of subword data
Many embedded architectures support indirect addressing mode with autoincrement/autodecrement. By maximizing the use of this mode, generation of explicit instructions for performing address arithmetic can be avoided and thus reductions in code size and improvements in performance are achieved. Bartley [2] and Liao et al. [16] developed a method for finding a storage layout for program variables so that the use of autoincrement/autodecrement could be maximized. They introduced the Simple Offset Assignment (SOA) problem and solved it using a Path Cover (PC) formulation.We observe that many media and network processing applications make extensive use of subword data. Therefore, for such applications, by packing multiple subword variables into a single word, we can generate storage layouts that further reduce the cost of address arithmetic in two ways. First the need for address arithmetic is reduced as variables that are packed together share the same address. Second opportunities for using autoincrement andautodecrement instructions are increased as layouts are now possible which place a variable adjacent to more than two variables. This approach has become feasible because of the recent trend in embedded processor design which allows subword variables that are packed together to be accessed and manipulated without incurring performance penalty. We introduce the SubWord Offset Assignment (SWOA) problem and solve it using a Path Cover with Node Coalescing (PCwNC) formulation. Node coalescing corresponds to packing of multiple subword variables into a single word while path covering corresponds to placement of variables in adjacent memory locations to enable the use of autoincrement/autodecrement. We present three heuristics to solve the PCwNC problem. Experiments show that when the program is optimized for code size, the three proposed algorithms achieve 26%, 26.9% and 32% reduction in the number of static explicit address arithmetic instructions over Liao et al.'s algorithm. The algorithms also achieve 14.5%, 22.1%and 22.7% reduction in stack frame size. If the program is optimized for performance, the algorithms achieve 24.3%, 24.7% and 30.2% reduction in the dynamic instruction count of explicit address arithmetic instructions.