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<concept xml:lang="en" id="GUID-49882982-0DA2-5021-BAC8-7DC77BDFD27C"><title>JPEG Exif Plug-in Library Overview </title><prolog><metadata><keywords/></metadata></prolog><conbody><p>This document introduces you to the JPEG Exif Plug-in library. It is intended for application developers and device creators who are interested in accessing Exif metadata in JPEG and TIFF images. </p> <section><title>Purpose</title> <p>JPEG Exif Plug-in provides a simplified mechanism for accessing the Exif metadata tags in JPEG images. </p> <p><b>JPEG Exif Plug-in Library Details</b> </p> <p>The DLL that provides the functionality and the library to which your code must link is identified below. </p> <table id="GUID-30FD8692-FE68-552C-91CF-C7666C415FC9"><tgroup cols="3"><colspec colname="col0"/><colspec colname="col1"/><colspec colname="col2"/><thead><row><entry>DLL</entry> <entry>LIB</entry> <entry>Short Description</entry> </row> </thead> <tbody><row><entry><p> <filepath> jpegexifplugin.dll</filepath>  </p> </entry> <entry><p> <filepath>jpegexifplugin.lib</filepath>  </p> </entry> <entry><p>A simplified mechanism for accessing the Exif metadata. </p> </entry> </row> </tbody> </tgroup> </table> </section> <section><title>Architectural Relationship</title> <p>JPEG Exif Plug-in is a member of the Imaging Framework component. It is used by several image framework libraries, including: </p> <ul><li id="GUID-6683751B-BA46-5633-98B9-F3065EA5615F"><p><xref href="GUID-27220B08-B2E7-5106-9BCC-C86938D3E37D.dita">Image Display</xref> - <xref href="GUID-6B918282-75B5-3E2F-B3E1-1955B6EBE907.dita"><apiname>CImageDisplay</apiname></xref> Handles the image decoding operation, providing scope for accessing Exif metadata on a read-only basis. </p> </li> <li id="GUID-A89A7F4C-8A47-50BE-ACC4-4750D8E925E5"><p><xref href="GUID-6914EA3D-6FAB-52DD-A159-990F4ED892A2.dita">Image Transformation</xref> - <xref href="GUID-37B0C02C-F518-3ADD-8828-90FD6B3E9DE4.dita"><apiname>CImageTransform</apiname></xref> Handles image transform operations such as image resizing and rotation. </p> </li> <li id="GUID-FABEEAD6-1566-5011-B4D1-85B85A2FCDB9"><p><xref href="GUID-FCEE832C-5D8D-5177-A86A-E10015EF77DC.dita"> Exif Utility</xref> - Provides Exif metadata access through <xref href="GUID-27F068D2-F5BE-3D0B-83F4-493A783CFB80.dita"><apiname>MExifMetadataWriter</apiname></xref> and <xref href="GUID-B742FC40-2D88-3E71-8F89-FCB15A2C6619.dita"><apiname>MExifMetadataReader</apiname></xref>. </p> </li> </ul> </section> <section><title>Description</title> <p>JPEG Exif Plug-in provides access to metadata in JPEG images. The complete list is available from the <xref scope="external" href="http://www.exif.org">Exif web site</xref>. </p> </section> <section><title>Key JPEG Exif Plug-in Classes</title> <p>JPEG Exif Plug-in allows you to read Exif metadata tags from and write to JPEG images. </p> <ul><li id="GUID-4017CAEA-AD05-5CCC-AF7B-CB1C1E48631D"><p> <xref href="GUID-8AA987C9-456B-3E7C-95C2-C5578EE977B9.dita"><apiname>TExifReaderUtility</apiname></xref> reads several pre-defined tags from a JPEG image. </p> </li> <li id="GUID-32FA97F2-17D4-517A-83CD-B28BBC2295D8"><p> <xref href="GUID-62EA502C-FBE8-39A8-AEC6-3104C15F18C9.dita"><apiname>TExifWriterUtility</apiname></xref> writes several pre-defined tags to a JPEG image. </p> </li> </ul> </section> <section><title>Using JPEG Exif Plug-in</title> <p>JPEG Exif Plug-in is used for: </p> <ul><li id="GUID-62620CFA-D317-5D39-9CA9-A02ADBF7ECB1"><p>Reading Exif metadata from JPEG images with the pre-defined Exif tag getter functions. </p> </li> <li id="GUID-2C34F487-74A9-51B4-98AE-840721559FE7"><p>Writing Exif Metadata tags to JPEG images with the pre-defined Exif tag setter functions. </p> </li> </ul> </section> </conbody><related-links><link href="GUID-1FC88405-616F-5ED1-A136-9FE1E9226F0E.dita"><linktext>Exif Utility Overview</linktext> </link> <link href="GUID-1FC88405-616F-5ED1-A136-9FE1E9226F0E.dita"><linktext>Exif Utility Guide</linktext> </link> <link href="GUID-27220B08-B2E7-5106-9BCC-C86938D3E37D.dita"><linktext>Image Display Library</linktext> </link> <link href="GUID-6914EA3D-6FAB-52DD-A159-990F4ED892A2.dita"><linktext>Image Transform Library</linktext> </link> </related-links></concept>