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<concept xml:lang="en" id="GUID-27220B08-B2E7-5106-9BCC-C86938D3E37D"><title>Image Display Library Overview </title><prolog><metadata><keywords/></metadata></prolog><conbody><p>This document introduces you to the Image Display functionality. </p> <section><title>Purpose</title> <p>This function provides an interface to encode image into <xref href="GUID-683A1D42-2764-3EB7-BD19-9E12559199AB.dita"><apiname>CFbsBitmap</apiname></xref> object which can be easily displayed on the screen. </p> <p><b>Image Display 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-21EA8DF4-7F42-5FD7-9DF8-A04E417F2CDC"><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>imagedisplay.dll</filepath>  </p> </entry> <entry><p> <filepath>imagedisplay.lib</filepath>  </p> </entry> <entry><p>These files are used for implementing image display operation. </p> </entry> </row> </tbody> </tgroup> </table> </section> <section><title>Architectural Relationship</title> <p>Image Display function plays an important role for displaying the still image. </p> <p>Furthermore, the <xref href="GUID-6B918282-75B5-3E2F-B3E1-1955B6EBE907.dita"><apiname>CImageDisplay</apiname></xref> also incorporates a function <xref href="GUID-8652E897-DD50-3976-A5A2-2150DA2D7A79.dita"><apiname>ExifMetadata</apiname></xref> in its plugin to access Exif metadata and display it. For more details see <xref href="GUID-FCEE832C-5D8D-5177-A86A-E10015EF77DC.dita">Exif support in CImageDisplay</xref>. </p> </section> <section><title>Description</title> <p>This functionality is similar to <xref href="GUID-8F2953B2-E64E-3D8B-B30B-B35B373368D4.dita"><apiname>CImageDecoder</apiname></xref>, but <xref href="GUID-6B918282-75B5-3E2F-B3E1-1955B6EBE907.dita"><apiname>CImageDisplay</apiname></xref> provides some more features which is listed in <xref href="GUID-27220B08-B2E7-5106-9BCC-C86938D3E37D.dita#GUID-27220B08-B2E7-5106-9BCC-C86938D3E37D/GUID-64B1FA61-EB99-5AAA-8077-B9422BA8011D">Using Image Display</xref>. </p> <p>The client application states where the source image is to be taken from. The image can be read either from a descriptor, or a file. The only other mandatory parameter supplied by the client is the size (in pixels) of the destination image. Additional (optional) parameters can be specified such as the designation of a clipping region for pan/zoom, but these are not necessarily supported by all ImageDisplay plugins. </p> </section> <section><title>Key Image Display Classes</title> <p>The key class is: </p> <ul><li id="GUID-CB155D7E-F6D9-5EC8-B8C7-1AE05DDC2504"><p> <xref href="GUID-6B918282-75B5-3E2F-B3E1-1955B6EBE907.dita"><apiname>CImageDisplay</apiname></xref> provides a convenient interface to convert encoded images into internal Symbian platform bitmap objects ready to be displayed on the screen. As part of decoding process scaling and rotation can be done. </p> </li> </ul> </section> <section id="GUID-64B1FA61-EB99-5AAA-8077-B9422BA8011D"><title>Using Image Display</title> <p>The Image Display functionality is used for the following: </p> <ul><li id="GUID-8FA7F198-BA78-52C2-8543-49B54385460A"><p>To encode image into <xref href="GUID-683A1D42-2764-3EB7-BD19-9E12559199AB.dita"><apiname>CFbsBitmap</apiname></xref> object. </p> </li> <li id="GUID-D31183C0-CCA4-5977-A741-E0F1C26ADE6E"><p>Scaling and rotation are provided in the decoding process. </p> </li> <li id="GUID-59F41B2A-F1FC-5B5F-B48C-FFD37A2B9E3E"><p>Progressive decoding is possible; for example, an unscaled (or roughly scaled) image may be displayed temporarily during the scaling process. This feature can be used to improve perceived responsiveness. </p> </li> </ul> </section> </conbody><related-links><link href="GUID-88091838-03FC-550F-9A3D-DA70907EF955.dita"><linktext>Imaging Frameworks Overview</linktext> </link> <link href="GUID-3D9C4B45-EEA0-581C-A9E5-8B2535014930.dita"><linktext>Image Conversion Overview</linktext> </link> <link href="GUID-6914EA3D-6FAB-52DD-A159-990F4ED892A2.dita"><linktext>Image Transform Overview</linktext> </link> <link href="GUID-27220B08-B2E7-5106-9BCC-C86938D3E37D.dita"><linktext>Image Display Overview</linktext> </link> <link href="GUID-6DC34798-86CE-537D-B3B8-9A94FF77B283.dita"><linktext>Image Encoding Tutorial</linktext> </link> <link href="GUID-B10B048F-37FF-53E7-92B9-83F8C197566A.dita"><linktext>Image Decoding Tutorial</linktext> </link> <link href="GUID-A825B62E-B5F6-5FDD-B267-E47103D57FD8.dita"><linktext>Guide to Symbian supplied Codecs</linktext> </link> </related-links></concept>