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<concept xml:lang="en" id="GUID-AB5BD17E-F482-54A1-AE6F-4AEC178B2E0E"><title> Overview</title><prolog><metadata><keywords/></metadata></prolog><conbody><p>This document introduces to the Overlay API. </p> <section><title>Purpose</title> <p>This provides support for image overlays. It is used to overlay an image onto the viewfinder, snapshots, still images and video. </p> <p><b>Overlay API 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-9AD06CC5-2348-5CE0-84CC-5FD536881ACA"><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> <xref href="GUID-0DB2FE27-331D-3F91-BAD0-64A9C2EF6EEC.dita"><apiname>ecamoverlay.dll </apiname></xref>  </p> </entry> <entry><p> <xref href="GUID-645E6782-2610-3E79-A6A8-66A65C325E5F.dita"><apiname>euser.lib </apiname></xref>  </p> <p> <xref href="GUID-EA31C23F-8081-3A82-ABAA-168F970B5381.dita"><apiname>ecampluginsupport.lib </apiname></xref>  </p> <p> <xref href="GUID-F6ECE528-3581-3503-BD94-77BFA16CFAA3.dita"><apiname>fbscli.lib </apiname></xref>  </p> <p> <xref href="GUID-B4E2E996-CFBE-3156-B02D-D0F2F634B3C7.dita"><apiname>ecam.lib </apiname></xref>  </p> </entry> <entry><p>These files are used for implementing the Overlay functionalities. </p> </entry> </row> </tbody> </tgroup> </table> </section> <section><title>Architectural Relationship</title> <p>This is part of the camera component. </p> </section> <section><title>Description</title> <p>Overlay is an image which is superimposed on top of the main image with a required transparency. The main image can be a single image during image capture mode (still image/ burst/ bracket), video image frame, snapshot image, or image frames for viewfinder (direct or client-based). </p> </section> <section><title>Key Overlay API Classes</title> <p>The key classes that make up the Overlay are as follows: </p> <p> <xref href="GUID-021C509B-C821-3401-B2F4-DE7F52BB16D4.dita#GUID-021C509B-C821-3401-B2F4-DE7F52BB16D4/GUID-5CF1EE7D-EAED-39F7-AF9D-73DD813B64F9"><apiname>CCamera::CCameraOverlay</apiname></xref>: This class provides support for image overlays. The client can use it to overlay an image onto the view finder, snapshots, still images and video. A client can create multiple overlays, where each overlay can be in a different format. The properties of an overlay can be changed after it has been created. </p> <p> <xref href="GUID-D54E15C8-4952-3A9C-807A-BC7DABB087D4.dita"><apiname>McameraOverlay</apiname></xref>: An interface class, for which Licensees need to provide implementation. </p> <p> <xref href="GUID-9C5233B4-6BD6-3139-B0B7-B01B14C18D2B.dita"><apiname>MCameraOverlay2</apiname></xref>: An interface class, for which the providers of the camera extension API for extra features of image overlays must provide implementation. </p> </section> <section><title>Using Overlay API</title> <p>Clients can use the Overlay to: </p> <ul><li id="GUID-B469F00E-CCC8-5DDA-A3A9-B055AA21154C"><p>overlay an image onto the viewfinder, snapshots, still images and video. </p> </li> <li id="GUID-F44D372D-5480-5473-82CD-F7A7BA5DB919"><p>create multiple overlays, where each overlay can be in a different format </p> </li> </ul> </section> <section><title>See also</title> <p><xref href="GUID-36C3A2FD-F4F9-5B8C-91B7-40C29B3D2224.dita">Overview</xref> of Camera Framework </p> <p>The <xref href="GUID-10E19876-85CA-5D45-854B-1F2C5A45A333.dita">Overlay</xref> tutorial </p> </section> </conbody></concept>