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<concept id="GUID-80EC80E2-E197-50F7-B1FD-720A00AC3B4D" xml:lang="en"><title>Onboard

Camera Overview</title><prolog><metadata><keywords/></metadata></prolog><conbody>

<p>This document introduces you to the Onboard Ecam API. </p>

<section id="GUID-09FDE5EA-AF80-4129-913F-C1DA9D82E73E"><title>Purpose</title> <p>The Onboard Camera provides functionality

to control a digital camera and to request and receive specific image data

from it. Still or video images may be captured. A camera may be controlled

with its output media going into a non-Symbian platform sink (for example,

into hardware), or it may be controlled with output going into the Symbian

platform. </p> <p>The API defines basic common operations, but is also extensible

to allow for proprietary properties. </p> <p><b>Onboard

Ecam 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-5DF138D2-3ADC-5BCD-ADCD-D04240B33DC9">

<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-37F3C935-D1DB-3993-B3E0-A56991462D77.dita"><apiname>ecam.dll</apiname></xref>  </p> </entry>

<entry><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 Onboard Camera functions. </p> </entry>

</row>

</tbody>

</tgroup>

</table> </section>

<section id="GUID-7ECFC164-8751-4DBE-93E2-9B0CF275CBB0"><title>Architectural Relationship</title> <p>The Onboard Camera provides

images to clients. A client may be an application with image requirements,

or the Multimedia Framework. Clients have specific priorities and may pre-empt

others in their interactions with the camera. </p> <p>Licensees and partners

implement the camera functionality for the camera hardware on their phone.

All cameras are ECom plug-ins sub-classed from the <xref href="GUID-A738B809-754B-3090-9209-0880687F173C.dita"><apiname>CCameraPlugin</apiname></xref> class. </p> <p>When

a new camera object is required, the ECam library requests a camera plug-in

from the ECom framework. When more than one ROM based plug-ins have been registered

on the platform, the one with the highest version defined in its resource

file is selected. </p> </section>

<section id="GUID-22512109-39BA-4E88-B615-609A60A5F199"><title>Description</title> <p>Client Applications can use the onboard

camera function for a number of tasks, including: </p> <p>Controlling camera

power, using the view finder, making basic camera image settings, capturing

a still image, capturing video, making advanced settings, getting snapshots,

getting image histograms, using image overlays, using preset camera settings,

image processing on the camera. </p> </section>

<section id="GUID-1AC509C3-E1D9-5DB4-9C09-90E0DCE576CB"><title>Key Onboard

Ecam API Classes</title> <p>The key classes that make up the Onboard Camera

are as follows: </p> <ul>

<li id="GUID-7D8751E9-C2B3-50DA-9B1C-6AC29FF592FA"><p> <xref href="GUID-021C509B-C821-3401-B2F4-DE7F52BB16D4.dita"><apiname>CCamera</apiname></xref>  </p> <p>It

provides the base class for camera devices. This is the interface that the

client application uses to communicate with the camera. It provides all the

functions necessary to control, and acquire images from, the camera. </p> </li>

<li id="GUID-F8732ED8-D86C-591C-93FF-89BF4386FCE9"><p> <xref href="GUID-09C6DDB6-A208-3C81-9F54-697D4865D99F.dita"><apiname>MCameraObserver2</apiname></xref>  </p> <p>It

is an observer class which permits access to picture data as descriptors,

bitmaps or chunks. It defines an event-handling interface that is called when

events are generated from use of the camera functions, or from external sources

such as the camera being plugged or unplugged. </p> <p> <xref href="GUID-F2DC0AB8-A896-3F7A-BBED-848A3F463853.dita"><apiname>MCameraObserver</apiname></xref> is

an earlier version of this callback interface. </p> </li>

<li id="GUID-DB8CCF2A-54DA-565E-8CD4-DEE608AAB1CA"><p> <xref href="GUID-644E96EC-EFDC-335D-B2B6-A1BDB8538C0A.dita"><apiname>TCameraInfo</apiname></xref>  </p> <p>It

provides information about the camera. This includes: the version number and

name of camera hardware, camera orientation, whether the camera supports still

image capture and so on. </p> </li>

<li id="GUID-4A214B79-32AD-5BBC-AD34-084A9C960F50"><p> <xref href="GUID-7F66BE6C-9998-3F16-AD55-F6FDF6CB351F.dita"><apiname>MCameraBuffer</apiname></xref>  </p> <p>It

is the buffer class used by <codeph>MCameraObserver2</codeph> to pass back

view finder data, images and video frames. It enables the client to choose

in which way it accesses the picture data (descriptor, bitmap or kernel chunk). </p> </li>

<li id="GUID-C76A2F13-FC4F-5ABA-A818-B6031F4FB116"><p> <xref href="GUID-2773C25B-19DF-38B0-84F7-CABC89F43DD2.dita"><apiname>TECAMEvent</apiname></xref>  </p> <p>It

is a simple event class containing a UID to identify the event and a status

code. It is passed to <xref href="GUID-09C6DDB6-A208-3C81-9F54-697D4865D99F.dita"><apiname>MCameraObserver2</apiname></xref> as functional argument

using <xref href="GUID-08E0AF71-E21B-30FC-88AA-E822A40F61F5.dita"><apiname>HandleEvent</apiname></xref> method, when a request is completed.

The request is complete, if a control of the camera switches, camera hardware

settings changes, or due to external events such as the camera being plugged

in. </p> <p>Use a derived version of <codeph>TECAMEvent</codeph> and <codeph>TECAMEvent2</codeph> to

pass additional information required by extended API to the API client along

with the error event code. </p> </li>

<li id="GUID-F1E7A83E-6382-51FC-8E19-9F66CB1844CD"><p> <xref href="GUID-021C509B-C821-3401-B2F4-DE7F52BB16D4.dita#GUID-021C509B-C821-3401-B2F4-DE7F52BB16D4/GUID-E31AEB11-B7A0-3637-BB31-866306F78118"><apiname>CCamera::CCameraAdvancedSettings</apiname></xref>  </p> <p>It

provides domain specific get and set methods for well known camera hardware

settings that relate directly to the image acquisition phase for both still

images and video. </p> </li>

<li id="GUID-A8284E63-1463-547D-9FB1-F2C9AA9FBA01"><p> <xref href="GUID-021C509B-C821-3401-B2F4-DE7F52BB16D4.dita#GUID-021C509B-C821-3401-B2F4-DE7F52BB16D4/GUID-6750F61A-455B-371E-893B-090350DCB704"><apiname>CCamera::CCameraPresets</apiname></xref>  </p> <p>It

associates a single command with setting of several camera parameters to specific

values (and ranges). The class allows clients without knowledge of the camera

specifics to achieve comparable results for different cameras. </p> </li>

<li id="GUID-135AC315-B294-5587-B71C-379D0CBF4547"><p> <xref href="GUID-021C509B-C821-3401-B2F4-DE7F52BB16D4.dita#GUID-021C509B-C821-3401-B2F4-DE7F52BB16D4/GUID-BD60287B-40A3-39D5-9C7B-7ABF976659B6"><apiname>CCamera::CCameraImageProcessing </apiname></xref>  </p> <p>It

is used to perform image processing operations on still images, video, viewfinder

(both client and direct). These include brightness, contrast, gamma, hue,

sharpness and saturation adjustments on the camera. The client is also able

to perform simple image transformations like cropping, rotation, mirroring,

scaling, noise reduction and glare reduction. </p> </li>

<li id="GUID-15E61113-8CE9-527B-A52C-B3A180B9960D"><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>  </p> <p>It

allows the client to overlay an image onto the view finder, snapshots, still

images, and video. </p> </li>

<li id="GUID-B8569488-6C25-5304-9A9E-8AAC964BCB06"><p> <xref href="GUID-021C509B-C821-3401-B2F4-DE7F52BB16D4.dita#GUID-021C509B-C821-3401-B2F4-DE7F52BB16D4/GUID-4E270B4A-074C-3531-9789-123C8AE899F0"><apiname>CCamera::CCameraHistogram</apiname></xref> allows

the client to get histogram data (<xref href="GUID-5064D139-1B97-394C-8C7D-417F72444F75.dita"><apiname>MHistogramBuffer</apiname></xref>) in

a specified format for an image, such as a luminance-based, or average colour

value histogram. </p> <p>This class is deprecated, so use<xref href="GUID-021C509B-C821-3401-B2F4-DE7F52BB16D4.dita#GUID-021C509B-C821-3401-B2F4-DE7F52BB16D4/GUID-E159F066-0157-34B4-B154-38D120EAB16C"><apiname>CCamera::CCameraV2Histogram</apiname></xref> class. </p> </li>

<li id="GUID-7DAA023E-D0A5-598D-B97F-9C706A8D44DD"><p> <xref href="GUID-021C509B-C821-3401-B2F4-DE7F52BB16D4.dita#GUID-021C509B-C821-3401-B2F4-DE7F52BB16D4/GUID-7DB06650-199E-3B00-A19A-1B48D671E46E"><apiname> CCamera::CCameraSnapshot</apiname></xref>  </p> <p>It

allows the client to request snapshot data in a specified image format for

both still images and video. Snapshot object can be created specifically for

still images and video APIs. </p> </li>

<li id="GUID-B25BB7CA-8FDC-5344-BCDB-9C2018248B67"><p> <xref href="GUID-021C509B-C821-3401-B2F4-DE7F52BB16D4.dita#GUID-021C509B-C821-3401-B2F4-DE7F52BB16D4/GUID-144A45FA-EADE-3036-B013-821F65142C82"><apiname>CCamera::CCameraDirectViewFinder</apiname></xref> used

for those viewfinders that use only viewfinder APIs of Ccamera. It provides

support for Direct View Finder functionalities, such as pause and resume.

see also <xref href="GUID-367ADFD7-A0F5-59D3-BF83-913CB8126B9D.dita">Viewfinder

API Overview</xref>. </p> </li>

<li id="GUID-F2BE13B7-5ADB-5E16-B2D3-CFB88A72068F"><p> <xref href="GUID-021C509B-C821-3401-B2F4-DE7F52BB16D4.dita#GUID-021C509B-C821-3401-B2F4-DE7F52BB16D4/GUID-4618B02E-CD2E-3DEA-979F-4C55AE3D45EC"><apiname> CCamera::CCameraClientViewFinder</apiname></xref>  </p> <p>It

provides support for multiple client View Finder. </p> </li>

<li id="GUID-44C02BC0-02AE-5EDA-82FC-1F1DE23210B3"><p> <xref href="GUID-021C509B-C821-3401-B2F4-DE7F52BB16D4.dita#GUID-021C509B-C821-3401-B2F4-DE7F52BB16D4/GUID-7B13335C-10A9-38D2-AE12-A50ECCF7EA58"><apiname> CCamera::CCameraPreImageCaptureControl</apiname></xref>  </p> <p>It

allows to control image operations or its settings prior to image capture. </p> </li>

<li id="GUID-65E481B6-DEEC-57DD-98EC-A7D8433D5DEF"><p> <xref href="GUID-021C509B-C821-3401-B2F4-DE7F52BB16D4.dita#GUID-021C509B-C821-3401-B2F4-DE7F52BB16D4/GUID-4F2BB371-3FE1-3FC5-800B-67B6472FE0E4"><apiname>CCamera::CCameraImageCapture</apiname></xref>  </p> <p>It

captures the image and controls the overall capture. </p> </li>

<li id="GUID-9A6713D4-C284-545E-BD40-9269DBD2C573"><p> <xref href="GUID-021C509B-C821-3401-B2F4-DE7F52BB16D4.dita#GUID-021C509B-C821-3401-B2F4-DE7F52BB16D4/GUID-C607DA37-D386-3291-A9C5-AD0E302607D3"><apiname> CCamera::CCameraPostImageCaptureControl</apiname></xref>  </p> <p>It

retrieves the image data from individual images and also controls the captured

images individually. </p> </li>

<li id="GUID-FBBF3E1B-D511-5AFB-8AE5-E996AD7CC4FC"><p> <xref href="GUID-021C509B-C821-3401-B2F4-DE7F52BB16D4.dita#GUID-021C509B-C821-3401-B2F4-DE7F52BB16D4/GUID-D74635DE-C5D8-3A9A-ABDD-8324D8EFF460"><apiname>CCamera::CCameraVideoCaptureControl</apiname></xref>  </p> <p>It

controls the operations related to video capture. </p> </li>

</ul> <p>The class diagram of CCamera is shown below: </p> <fig id="GUID-E2F73C42-38F9-5EE1-B5EB-C255B42E0621">

</fig> </section>

<section id="GUID-29660557-F0B3-4400-A482-CEEE36A7B3F4"><title>Using Onboard Ecam API</title> <p>The clients can use CCamera

function to control and acquire image data from the camera. </p> </section>

<section id="GUID-16BFDFCF-2805-402D-911B-A1A81A8BF50C"><title>See also</title> <p><xref href="GUID-36C3A2FD-F4F9-5B8C-91B7-40C29B3D2224.dita">Camera

Framework Overview</xref>  </p> <p><xref href="GUID-55A1A47A-A7DD-5B1A-88E1-4818CB65B782.dita">Camera

Tutorials</xref>  </p> </section>

</conbody></concept>