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<concept xml:lang="en" id="GUID-257E223F-1612-5978-982A-38DE8E08211C"><title> Gifscaler Library Overview </title><prolog><metadata><keywords/></metadata></prolog><conbody><p>This document introduces you to the Gifscaler library functionality. </p> <section id="GUID-7CD260AE-8FE3-57A5-914D-D0CCC18C562A"><title>Purpose</title> <p>The GifScaler functionality provides scaling and colour quantization of bitmaps as asynchronous operations. </p> <p><b>Gifscaler Library Details</b> </p> <p>You must obtain necessary binaries in the form of DLL file to implement the Gifscaler function. </p> <table id="GUID-071830E2-B4E2-551B-8CB1-F7E54F3350E7"><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> gifscaler.dll</filepath>  </p> </entry> <entry><p> <filepath>gifscaler.lib</filepath>  </p> </entry> <entry><p>These files are used for implementing Gifscaler operation. </p> </entry> </row> </tbody> </tgroup> </table> </section> <section><title>Architectural Relationship</title> <p>Gifscaler function plays an important role in Imaging Frameworks to provide bitmaps suitable for gif encoding. </p> </section> <section><title>Description</title> <p>Gifscaler is used to provide bitmaps suitable for gif encoding. The target bitmap is a 256 colours bitmap using a custom palette created by the GifScaler.dll. The transparency information is provided in the form of a mask bitmap. If transparency information is present the output palette contains 255 colours, the remaining palette entry is used for the transparent pixels. </p> </section> <section><title>Key Gifscaler Classes</title> <p>The key class is: </p> <ul><li id="GUID-3A0DDCF7-8A2F-5273-ABDA-16E506D27067"><p> <xref href="GUID-4CBAE460-BF54-3F8B-8E5D-BB7EA8633160.dita"><apiname>CGifScaler</apiname></xref> Provides scaling and colour quantization of bitmaps as asynchronous operations. It provides the client interface functionality to the GifScaler.dll. </p> </li> </ul> </section> <section><title>Using Gifscaler</title> <p>The Gifscaler functionality is used for the following: </p> <ul><li id="GUID-B4789044-9B9D-5A1C-BE15-5673BC51F69C"><p>To provide bitmaps suitable for gif encoding. </p> </li> <li id="GUID-C41824F6-7A49-5D87-B7E9-6D8627457A79"><p>To provide scaling of bitmaps as asynchronous operations. </p> </li> <li id="GUID-A47DB84B-C1D0-5347-A134-4CB0B9FE7259"><p>To provide colour quantization of bitmaps as asynchronous operations. </p> </li> <li id="GUID-1AA748D3-B321-5B3D-A4C7-61CD46BBDC61"><p>To use fast colour quantizer for the small bitmaps. </p> </li> <li id="GUID-1447F801-1A2A-5C2D-BCFA-AB576F655594"><p>To provide no memory allocation during the colour quantization process and therefore no <codeph>RunError()</codeph> method is required. </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 Library Overview</linktext> </link> <link href="GUID-6914EA3D-6FAB-52DD-A159-990F4ED892A2.dita"><linktext>Image Transform Library

                Overview</linktext> </link> <link href="GUID-27220B08-B2E7-5106-9BCC-C86938D3E37D.dita"><linktext>Image Display Library Overview</linktext> </link> <link href="GUID-C0B39D73-0A3C-5289-A774-7BE590037404.dita"><linktext>Bitmap Transform Library

                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>