1. Using XML In ViPER and More

2. XML Direct access to information, without worrying about parsing. XML Information Set –XML provides a way to access information independent of access, format, etc. –XML is just a serialization of a set of information arranged in a tree.

3. ViPER Tree viper –config descriptor –data sourcefile filename=“file.mpg” –file –object

4. ViPER File Format

5. Accessing Via XPath Get data from a specific file –/viper/data/sourcefile[@filename=“f.mpg”] Gets the sourcefile node –//sourcefile[@fname=“f.mpg]//bbox Gets all bbox nodes

6. Matlab with Java % Add xerces.jar to classpath.txt (find using 'which classpath.txt') % need to restart matlab after changing import org.apache.xerces.parsers.* org.w3c.dom.*; import java.lang.String org.xml.sax.*; input = InputSource('C:\MATLAB6p1\work\advertisements.xml'); parser = DOMParser; parser.setFeature('http://apache.org/xml/features/validation/schema', 0) parser.parse(input); doc = parser.getDocument; sfs = doc.getElementsByTagName('sourcefile') files = cell(sfs.getLength, 1); i = 0; while i < sfs.getLength fileattr = sfs.item(i).getAttributes.getNamedItem('filename'); i = i + 1; files(i) = fileattr.getValue; end

7. Perl use XML::LibXML; my $parser = XML::LibXML->new(); my $tree = $parser->parse_file($datafiles[0]); my $root = $tree->getDocumentElement; foreach my $source ($root->findnodes('sourcefile')){ my $image = $source->findvalue('@filename'); foreach my $d ($source- >findnodes('content|object')){ [$startFrame, $endFrame] = split(/:/,$d->findvalue('@framespan')); foreach my $shape ($d->findnodes(lc($attribType))) { $orig_x = $shape->findvalue( ‘@x' ); $orig_y = $shape->findvalue( ‘@y' );

8. C with libxml2 #include ---- xmlDocPtr doc = = xmlParseFile(‘truth.xml’); if (doc == NULL) return(NULL); xmlNodePtr cur = xmlDocGetRootElement(doc); xmlNsPtr viperns = xmlSearchNsByHref(doc, cur, (const xmlChar *) "http://lamp.cfar.umd.edu/viper"); cur = cur->xmlChildrenNode; while (cur != NULL) { if ((!strcmp(cur->name, “config”)) && (cur->ns == viperns)) parseConfig (doc, viperns, cur); else if ((!strcmp(cur->name, “data”)) && (cur->ns == viperns)) parseData (doc, viperns, cur); cur = cur->next; } xmlCleanupParser();

9. XML Databases Uses existing tools to access persistent data –DOM and XPath –XQuery and XUpdate Many different implementations –Open Source: Apache Xindice, eXist –Proprietary:TextML, X-Hive, –Relational: MS SQL, Oracle

10. XSL:Transformations The idea is to look at the incoming data as a tree, using XPath, and select various nodes to copy to the output. While the output does not have to be XML, the input and the document itself must be well formed. On system 7, ‘testXSLT’ runs stylesheets.

11. XSLT <xsl:stylesheet version=“1.0” xmlns:xsl=“http://www.w3.org/1999/XSL/Transform” xmlns:gtf=“http://lamp.cfar.umd.edu/viper” xmlns:data=“http://lamp.cfar.umd.edu/viperdata” xmlns:xsi="http://www.w3.org/2001/XMLSchema- instance">

12. XSLT #VIPER_VERSION_3.0 1 <xsl:template match="//gtf:sourcefile[starts-with(@filename, 'comm- 001')]">

13. CSS-1 Supported in the majority of browsers in use today. Basic styling. Hopefully will reduce reliance on HTML tables as a way to lay out web pages. p { font-size: 12pt; line-height: 18pt; } p:first-letter { font-size: 200%; float: left; }

14. CSS-2 Added support for pagination, including widow and orphan control, page breaks, and margins. Aural style sheets for voice browsing. Can be applied directly to XML. Possible to do some multi-column layout.

15. CSS-3 Modularized Through Ruby, support for Japanese, Arabic, etc. Multi-column layout Support for other W3C specs, like –SVG –MathML –SMIL

16. XSL:FO Basically, the idea is to put CSS-2 in an XML dialect, and use XPath and other XML technologies to make printed media look nice. Extremely verbose – designed to be generated from semantic markup. –However, its lack of semantics leads Opera CTO Lie to call them “Harmful.” Additions include footnotes, hyphenation, odd/even pages, citations for indices and tables of contents. RenderX, Apache FOP

17. Defining an XML Dialect Document Type Definitions –Simple, BNF type definition of tags, attributes, and how they may be arranged. Schema –XML based replacement for non-XML DTDs. –Complex. –Define data types, and associate them with tag names. Rule based constriction –Schematron

18. ViPER Schema <xsd:schema xmlns:xsd="http://www.w3.org/2001/XMLSchema" targetNamespace="http://lamp.cfar.umd.edu/viper" xmlns:viper="http://lamp.cfar.umd.edu/viper" elementFormDefault="qualified">

19. ViPER Data Schema <xsd:schema xmlns:xsd=“http://www.w3.org/2001/XMLSchema” targetNamespace=“http://lamp.cfar.umd.edu/viperdata” xmlns:viperdata=“http://lamp.cfar.umd.edu/viperdata” xmlns:viper=“http://lamp.cfar.umd.edu/viper” elementFormDefault=“qualified”> <xsd:import namespace=“http://lamp.cfar.umd.edu/viper” schemaLocation=“file:viper.xsd” />

20. MPEG-7 Based on XML-Schema. Extensions to deal better with video type data, including matrix data types, etc. Designed to work with any level of description, from low level to high. W3C has only a working draft for DOM access to schemas, so using generic MPEG- 7 documents is currently difficult.

21. Resources www.xml.com –O'Reilly's XML resource www.w3.org –The standards themselves, and lots of good links to implementations. xml.apache.org –DOM, SAX, and XSLT for C and Java xmlsoft.org –libxml creators msdn.microsoft.com/xml –MS-XML parser is the one to use on Windows. mpeg.telecomitalialab.com –MPEG-7 Working Group pyxml.sourceforge.net –Using xml with Python. okmij.org/ftp/Scheme/xml.html –Using XML with Scheme.