JPSearch RA

JPSearch > Part 2 > JPSearch Core Metadata Schema

JPSearch Core Metadata Schema

The JPSearch Core Metadata Schema is the main component of the metadata interoperability strategy in ISO/IEC 24800. It specifies the structure and rules to which any image metadata must conform in order to be considered valid within a JPSearch compliant system. The core schema serves as metadata basis supporting interoperability during search among multiple image retrieval systems. The core schema is used by clients to formulate, in combination with the JPEG Query Format, search requests to JPSearch compliant search systems. Note, that only metadata described by the core schema is guaranteed that its semantics is recognized by JPSearch compliant systems. The following example shows the description of a fictional image.

<?xml version="1.0" encoding="iso-8859-1"?>
<ImageDescription xmlns="urn:jpeg:jpsearch:schema:coremetadata:2009" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="urn:jpeg:jpsearch:schema:coremetadata:2009 24800-2-core.xsd">
  <Identifier>urn:unique:identifier:1:2:3</Identifier>  
  <Creators>
    <GivenName>John</GivenName>
    <FamilyName>Smith</FamilyName>
  </Creators>
  <CreationDate>2011-12-17T09:30:47.0Z</CreationDate>
  <ModifiedDate>2011-12-17T09:30:47.0Z</ModifiedDate>
  <Description>Sample description</Description>
  <Keyword>Sardinia</Keyword>
  <Keyword>Italy</Keyword>
  <Keyword>50th JPEG meeting</Keyword>
  <Title>Example Instance document of the JPSearch core schema</Title>  
  <GPSPositioning latitude="34" longitude="34" altitude="10"/>
  <RegionOfInterest>
    <RegionLocator>
      <Region dim="2"> 0 0 100 100</Region>
    </RegionLocator>
    <Description>A short description about the selected region
    </Description>
    <Keyword>plenary meeting</Keyword>
  </RegionOfInterest>
  <Width>640</Width> 
  <Height>480</Height>
</ImageDescription>

However, the core schema neither is intended to be the unique schema used for annotating images, nor is it intended to replace existing well-established metadata schemas such as MPEG-7 or Dublin Core. The JPSearch Core Metadata contains a set of minimal core terms that can be extended in two different ways:

1) By extending the Core Schema through ExternalDescription elements, as is in the following example:

2) By directly using a different metadata schema in the JPSearch-based interactions (annotation, querying, etc.) and defining and registering the proper translations to the core schema with the JPSearch Translation Rules Declaration Language, introduced in the next section.