Secondary camera in QML - Revision history

Hamishwillee: Text replace - "Category:Multimedia" to ""

2013-06-14T05:00:23Z

Text replace - "Category:Multimedia" to ""

Hamishwillee: Text replace - "`" to ""`


2012-10-11T01:18:34Z
Text replace - "<code cpp>" to "<code cpp-qt>"

			
			
			
			
		
		← Older revision
		Revision as of 01:18, 11 October 2012
		
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  The C++ part of the FrontCameraApp component is shown below:   The C++ part of the FrontCameraApp component is shown below:
    
− <code cpp> + <code cpp-qt>
  #include <QGraphicsVideoItem>   #include <QGraphicsVideoItem>
    
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  Lastly the FrontCameraApp object has to be registered for QML in the main.cpp file.   Lastly the FrontCameraApp object has to be registered for QML in the main.cpp file.
    
− <code cpp> + <code cpp-qt>
       qmlRegisterType<FrontCameraApp>("cz.vutbr.fit.pcmlich", 1, 0, "CameraFront");        qmlRegisterType<FrontCameraApp>("cz.vutbr.fit.pcmlich", 1, 0, "CameraFront");
  </code>   </code>
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  First download the source code from [http://qt.gitorious.org/qt-mobility gitorious]. The implementation of the Camera element is in /plugins/declarative/multimedia/qdeclarativecamera.cpp. Change the code as follows:   First download the source code from [http://qt.gitorious.org/qt-mobility gitorious]. The implementation of the Camera element is in /plugins/declarative/multimedia/qdeclarativecamera.cpp. Change the code as follows:
− <code cpp> + <code cpp-qt>
  QDeclarativeCamera::QDeclarativeCamera(QDeclarativeItem *parent) :   QDeclarativeCamera::QDeclarativeCamera(QDeclarativeItem *parent) :
       QDeclarativeItem(parent),        QDeclarativeItem(parent),
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  Next, it is necessary to add included private header files to your project.   Next, it is necessary to add included private header files to your project.
− <code cpp> + <code cpp-qt>
  #include "qdeclarativecamera_p.h"   #include "qdeclarativecamera_p.h"
  #include "qdeclarativecamerapreviewprovider_p.h"   #include "qdeclarativecamerapreviewprovider_p.h"



Hamishwillee: Hamishwillee - Subedit
2012-06-18T03:55:53Z
Hamishwillee - Subedit

			
			
			
			
		
		← Older revision
		Revision as of 03:55, 18 June 2012
		
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− [[Category:Qt]][[Category:Qt Mobility]][[Category:Multimedia]][[Category:MeeGo Harmattan]][[Category:Code Examples]][[Category:Code Snippet]] + [[Category:Qt]][[Category:Qt Mobility]][[Category:Multimedia]][[Category:MeeGo Harmattan]][[Category:Code Examples]][[Category:Camera]][[Category:Imaging]]
− {{Abstract|This article explains how to use the secondary camera in QML }} + {{Abstract|This article explains how to use the secondary (front-facing) camera in QML }}
  {{Note|This is an entry in the [[PureView Imaging Competition 2012Q2]]}}   {{Note|This is an entry in the [[PureView Imaging Competition 2012Q2]]}}
  {{ArticleMetaData <!-- v1.2 -->   {{ArticleMetaData <!-- v1.2 -->
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  == Introduction ==   == Introduction ==
    
− This article describes how to use the secondary camera in QML. The article [http://harmattan-dev.nokia.com/docs/library/html/guide/html/Developer_Library_Developing_for_Harmattan_Using_the_device_camera.html] describes how to use the primary camera in various ways. However, access to the secondary camera is not available in QML. + The reference library topic [http://harmattan-dev.nokia.com/docs/library/html/guide/html/Developer_Library_Developing_for_Harmattan_Using_the_device_camera.html Using the device camera] describes how to use the primary camera in various ways. However, access to the secondary camera is only available to C++ apps.
    
− == Current solution == + This article describes some options for using the secondary camera in QML. 
    
− The secondary camera (i.e. frontal camera) is available though the C++ API. The registration of the component in QML is possible. However, this component does not provide the methods which are in the QML Camera component [http://doc.qt.nokia.com/qtmobility-1.2/qml-camera.html]. + == Basic solution ==
    
− <code lang=cpp> + The secondary camera (i.e. front-facing camera) is available though the C++ API. The basic solution is to create a declarative component and expose this to QML.
  +  
  + First include multimedia in the project file.
  + <code>
  + CONFIG += mobility
  + MOBILITY += multimedia
  + </code>
  +  
  + The C++ part of the FrontCameraApp component is shown below:
  +  
  + <code cpp>
  #include <QGraphicsVideoItem>   #include <QGraphicsVideoItem>
    
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  </code>   </code>
    
− The multimedia part from qt mobility has to be included in project. + Lastly the FrontCameraApp object has to be registered for QML in the main.cpp file.
−   + 
− <code> + 
− CONFIG += mobility + 
− MOBILITY += multimedia + 
− </code> + 
−   + 
− Also, the FrontCameraApp object has to be registered for QML. + 
    
  <code cpp>   <code cpp>
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  </code>   </code>
    
− The use in QML is as follows: +  
  + Then use the new {{Icode|CameraFront}} element in QML is as follows:
    
  <code css>   <code css>
  import com.nokia.meego 1.0   import com.nokia.meego 1.0
  import cz.vutbr.fit.pcmlich 1.0   import cz.vutbr.fit.pcmlich 1.0
− // import QtMultimediaKit 1.1  
  Page {   Page {
     CameraFront {        CameraFront {  
       anchors.fill: parent;        anchors.fill: parent;
     }      }
− /*  
−  // or primary camera  
−   Camera {  
−     anchors.fill: parent;  
−   }  
− */  
  }   }
  </code>   </code>
    
− == Additional features == + == Advanced solution/workaround ==
−   + The basic solution above does not provide the methods which are in the [http://doc.qt.nokia.com/qtmobility-1.2/qml-camera.html QML Camera Element].  If you need more advanced functionality through the front-facing camera one approach is to simply modify the existing QML Element for the main camera to work with the front-facing camera.
− Since Qt mobility is open source, you can download the source codes from [http://qt.gitorious.org/qt-mobility]. The implementation of the Camera element is in /plugins/declarative/multimedia/qdeclarativecamera.cpp. In order to use of this class in your own project it is necessary to modify its code to work with secondary camera as follows: + 
    
  + First download the source code from [http://qt.gitorious.org/qt-mobility gitorious]. The implementation of the Camera element is in /plugins/declarative/multimedia/qdeclarativecamera.cpp. Change the code as follows:
  <code cpp>   <code cpp>
  QDeclarativeCamera::QDeclarativeCamera(QDeclarativeItem *parent) :   QDeclarativeCamera::QDeclarativeCamera(QDeclarativeItem *parent) :
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  </code>   </code>
    
− There could be a conflict in the class names QDeclarativeCamera and other problems, so it is recommended to perform refactoring of QDeclarativeCamera class. Finally, the modified class is registered into QML, as is described in the previous section. + There could be a conflict in the class names {{Icode|QDeclarativeCamera}} and other problems, so it is recommended to perform refactoring of {{Icode|QDeclarativeCamera}} class. Finally, the modified class is registered into QML, as is described in the previous section.
    
− == Problems == + == Flip the image==
    
  The image from the secondary camera could be confusing to the user. Therefore it is appropriate to flip it.     The image from the secondary camera could be confusing to the user. Therefore it is appropriate to flip it.  
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           transform: Rotation { origin.x: frontcam.width/2; origin.y: frontcam.height/2; axis { x: 0; y: 1; z: 0 } angle: 180  }            transform: Rotation { origin.x: frontcam.width/2; origin.y: frontcam.height/2; axis { x: 0; y: 1; z: 0 } angle: 180  }
  </code>   </code>
  + 
  + == Limitations ==
    
  The primary and secondary cameras cannot be opened at same time.   The primary and secondary cameras cannot be opened at same time.
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  == Summary ==   == Summary ==
    
− After these modifications, we have a QML component for the secondary camera which allows us modify white balance mode, exposure compensation, and other configuration of the secondary camera. It is also possible to capture images and monitor camera states. This solution is only a workaround, since the Qt Mobility is not providing a suitable interface for the secondary camera. All mentioned components are available in the attached file  [[Media:SecondaryCameraInQml.tar.gz]] + After these modifications, we have a QML component for the secondary camera which allows us modify white balance mode, exposure compensation, and other configuration of the secondary camera. It is also possible to capture images and monitor camera states. This solution is only a workaround, since the Qt Mobility is not providing a suitable interface for the secondary camera. All mentioned components are available in the attached file: [[Media:SecondaryCameraInQml.tar.gz]]




Hamishwillee: Hamishwillee - Bot update - Fix ArticleMetaData
2012-06-14T00:30:13Z
Hamishwillee - Bot update - Fix ArticleMetaData

			
			
			
			
		
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		Revision as of 00:30, 14 June 2012
		
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  |devicecompatability= must have secondary camera   |devicecompatability= must have secondary camera
  |dependencies= qt mobility   |dependencies= qt mobility
− |signing=<!-- Signing requirements - empty or one of: Self-Signed, DevCert, Manufacturer --> + |signing= <!-- Signing requirements - empty or one of: Self-Signed, DevCert, Manufacturer -->
  |capabilities= <!-- Capabilities required by the article/code example (e.g. Location, NetworkServices. -->   |capabilities= <!-- Capabilities required by the article/code example (e.g. Location, NetworkServices. -->
  |keywords= Camera, QML   |keywords= Camera, QML
  |language= <!-- Language category code for non-English topics - e.g. Lang-Chinese -->   |language= <!-- Language category code for non-English topics - e.g. Lang-Chinese -->
  |translated-by= <!-- [[User:XXXX]] -->   |translated-by= <!-- [[User:XXXX]] -->
− |translated-from-title= <!-- Title only -->   + |translated-from-title= <!-- Title only -->
  |translated-from-id= <!-- Id of translated revision -->   |translated-from-id= <!-- Id of translated revision -->
− |review-by=<!-- After re-review: [[User:username]] --> + |review-by= <!-- After re-review: [[User:username]] -->
  |review-timestamp= <!-- After re-review: YYYYMMDD -->   |review-timestamp= <!-- After re-review: YYYYMMDD -->
  |update-by= <!-- After significant update: [[User:username]]-->   |update-by= <!-- After significant update: [[User:username]]-->
  |update-timestamp= <!-- After significant update: YYYYMMDD -->   |update-timestamp= <!-- After significant update: YYYYMMDD -->
  |creationdate= 20120607   |creationdate= 20120607
− |author=  [[User:xmlich02]]   + |author= [[User:xmlich02]]
  }}   }}
    



Hamishwillee: Text replace - "Category:MeeGo" to "Category:MeeGo Harmattan"
2012-06-13T10:56:28Z
Text replace - "Category:MeeGo" to "Category:MeeGo Harmattan"

			
			
			
			
		
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		Revision as of 10:56, 13 June 2012
		
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− [[Category:Qt]][[Category:Qt Mobility]][[Category:Multimedia]][[Category:MeeGo]][[Category:Code Examples]][[Category:Code Snippet]] + [[Category:Qt]][[Category:Qt Mobility]][[Category:Multimedia]][[Category:MeeGo Harmattan]][[Category:Code Examples]][[Category:Code Snippet]]
  {{Abstract|This article explains how to use the secondary camera in QML }}   {{Abstract|This article explains how to use the secondary camera in QML }}
  {{Note|This is an entry in the [[PureView Imaging Competition 2012Q2]]}}   {{Note|This is an entry in the [[PureView Imaging Competition 2012Q2]]}}



Chintandave er: Chintandave er - updated article metadata
2012-06-09T08:41:56Z
Chintandave er - updated article metadata

			
			
			
			
		
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		Revision as of 08:41, 9 June 2012
		
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  |update-by= <!-- After significant update: [[User:username]]-->   |update-by= <!-- After significant update: [[User:username]]-->
  |update-timestamp= <!-- After significant update: YYYYMMDD -->   |update-timestamp= <!-- After significant update: YYYYMMDD -->
− |creationdate= <!-- Format YYYYMMDD --> + |creationdate= 20120607
− |author= <!-- Display as link [[User:username]] --> + |author=  [[User:xmlich02]]  
  }}   }}
    




Xmlich02: Xmlich02 -
2012-06-07T14:53:14Z
Xmlich02 -

			
			
			
			
		
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		Revision as of 14:53, 7 June 2012
		
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− [[Category:Draft]][[Category:Qt]][[Category:Qt Mobility]][[Category:Multimedia]][[Category:MeeGo]][[Category:Code Examples]][[Category:Code Snippet]] + [[Category:Qt]][[Category:Qt Mobility]][[Category:Multimedia]][[Category:MeeGo]][[Category:Code Examples]][[Category:Code Snippet]]
  {{Abstract|This article explains how to use the secondary camera in QML }}   {{Abstract|This article explains how to use the secondary camera in QML }}
  {{Note|This is an entry in the [[PureView Imaging Competition 2012Q2]]}}   {{Note|This is an entry in the [[PureView Imaging Competition 2012Q2]]}}




Xmlich02: Xmlich02 -
2012-06-07T14:47:11Z
Xmlich02 -

			
			
			
			
		
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		Revision as of 14:47, 7 June 2012
		
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  [[Category:Draft]][[Category:Qt]][[Category:Qt Mobility]][[Category:Multimedia]][[Category:MeeGo]][[Category:Code Examples]][[Category:Code Snippet]]   [[Category:Draft]][[Category:Qt]][[Category:Qt Mobility]][[Category:Multimedia]][[Category:MeeGo]][[Category:Code Examples]][[Category:Code Snippet]]
  {{Abstract|This article explains how to use the secondary camera in QML }}   {{Abstract|This article explains how to use the secondary camera in QML }}
− ''Enter article metadata as described below. Note that this template can be placed anywhere in the article. Do not remove parameters that you do not use''  
  {{Note|This is an entry in the [[PureView Imaging Competition 2012Q2]]}}   {{Note|This is an entry in the [[PureView Imaging Competition 2012Q2]]}}
  {{ArticleMetaData <!-- v1.2 -->   {{ArticleMetaData <!-- v1.2 -->
− |sourcecode= <!-- Link to example source code e.g. [[Media:The Code Example ZIP.zip]] --> + |sourcecode= [[Media:SecondaryCameraInQml.tar.gz]]
  |installfile= <!-- Link to installation file (e.g. [[Media:The Installation File.sis]]) -->   |installfile= <!-- Link to installation file (e.g. [[Media:The Installation File.sis]]) -->
  |devices= N9   |devices= N9
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  == Summary ==   == Summary ==
    
− After these modifications, we have a QML component for the secondary camera which allows us modify white balance mode, exposure compensation, and other configuration of the secondary camera. It is also possible to capture images and monitor camera states. This solution is only a workaround, since the Qt Mobility is not providing a suitable interface for the secondary camera. All mentioned components are available in the attached file [FIXME] + After these modifications, we have a QML component for the secondary camera which allows us modify white balance mode, exposure compensation, and other configuration of the secondary camera. It is also possible to capture images and monitor camera states. This solution is only a workaround, since the Qt Mobility is not providing a suitable interface for the secondary camera. All mentioned components are available in the attached file  [[Media:SecondaryCameraInQml.tar.gz]]



Xmlich02: Xmlich02 -
2012-06-07T14:45:44Z
Xmlich02 -

			
			
			
			
		
		← Older revision
		Revision as of 14:45, 7 June 2012
		
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− [[Category:Draft]] + [[Category:Draft]][[Category:Qt]][[Category:Qt Mobility]][[Category:Multimedia]][[Category:MeeGo]][[Category:Code Examples]][[Category:Code Snippet]]
  {{Abstract|This article explains how to use the secondary camera in QML }}   {{Abstract|This article explains how to use the secondary camera in QML }}
  ''Enter article metadata as described below. Note that this template can be placed anywhere in the article. Do not remove parameters that you do not use''   ''Enter article metadata as described below. Note that this template can be placed anywhere in the article. Do not remove parameters that you do not use''
  + {{Note|This is an entry in the [[PureView Imaging Competition 2012Q2]]}}
  {{ArticleMetaData <!-- v1.2 -->   {{ArticleMetaData <!-- v1.2 -->
  |sourcecode= <!-- Link to example source code e.g. [[Media:The Code Example ZIP.zip]] -->   |sourcecode= <!-- Link to example source code e.g. [[Media:The Code Example ZIP.zip]] -->
  |installfile= <!-- Link to installation file (e.g. [[Media:The Installation File.sis]]) -->   |installfile= <!-- Link to installation file (e.g. [[Media:The Installation File.sis]]) -->
− |devices= <!-- Devices tested against - e.g. ''devices=Nokia 6131 NFC, Nokia C7-00'') --> + |devices= N9
  |sdk= <!-- SDK(s) built and tested against (e.g. [http://linktosdkdownload/ Qt SDK 1.1.4]) -->   |sdk= <!-- SDK(s) built and tested against (e.g. [http://linktosdkdownload/ Qt SDK 1.1.4]) -->
− |platform= <!-- Compatible platforms - e.g. Symbian^1 and later, Qt 4.6 and later --> + |platform= Qt 4.6 and later
− |devicecompatability= <!-- Compatible devices e.g.: All* (must have internal GPS) --> + |devicecompatability= must have secondary camera
− |dependencies= <!-- Any other/external dependencies e.g.: Google Maps Api v1.0 --> + |dependencies= qt mobility
  |signing=<!-- Signing requirements - empty or one of: Self-Signed, DevCert, Manufacturer -->   |signing=<!-- Signing requirements - empty or one of: Self-Signed, DevCert, Manufacturer -->
  |capabilities= <!-- Capabilities required by the article/code example (e.g. Location, NetworkServices. -->   |capabilities= <!-- Capabilities required by the article/code example (e.g. Location, NetworkServices. -->
− |keywords= <!-- APIs, classes and methods (e.g. QSystemScreenSaver, QList, CBase --> + |keywords= Camera, QML
  |language= <!-- Language category code for non-English topics - e.g. Lang-Chinese -->   |language= <!-- Language category code for non-English topics - e.g. Lang-Chinese -->
  |translated-by= <!-- [[User:XXXX]] -->   |translated-by= <!-- [[User:XXXX]] -->



Xmlich02: Xmlich02 -
2012-06-07T14:36:43Z
Xmlich02 -
New page
[[Category:Draft]]

{{Abstract|This article explains how to use the secondary camera in QML }}

''Enter article metadata as described below. Note that this template can be placed anywhere in the article. Do not remove parameters that you do not use''

{{ArticleMetaData <!-- v1.2 -->

|sourcecode= <!-- Link to example source code e.g. [[Media:The Code Example ZIP.zip]] -->

|installfile= <!-- Link to installation file (e.g. [[Media:The Installation File.sis]]) -->

|devices= <!-- Devices tested against - e.g. ''devices=Nokia 6131 NFC, Nokia C7-00'') -->

|sdk= <!-- SDK(s) built and tested against (e.g. [http://linktosdkdownload/ Qt SDK 1.1.4]) -->

|platform= <!-- Compatible platforms - e.g. Symbian^1 and later, Qt 4.6 and later -->

|devicecompatability= <!-- Compatible devices e.g.: All* (must have internal GPS) -->

|dependencies= <!-- Any other/external dependencies e.g.: Google Maps Api v1.0 --> 

|signing=<!-- Signing requirements - empty or one of: Self-Signed, DevCert, Manufacturer -->

|capabilities= <!-- Capabilities required by the article/code example (e.g. Location, NetworkServices. -->

|keywords= <!-- APIs, classes and methods (e.g. QSystemScreenSaver, QList, CBase -->

|language= <!-- Language category code for non-English topics - e.g. Lang-Chinese -->

|translated-by= <!-- [[User:XXXX]] -->

|translated-from-title= <!-- Title only --> 

|translated-from-id= <!-- Id of translated revision -->

|review-by=<!-- After re-review: [[User:username]] -->

|review-timestamp= <!-- After re-review: YYYYMMDD -->

|update-by= <!-- After significant update: [[User:username]]-->

|update-timestamp= <!-- After significant update: YYYYMMDD -->

|creationdate= <!-- Format YYYYMMDD -->

|author= <!-- Display as link [[User:username]] -->

}}



== Introduction ==



This article describes how to use the secondary camera in QML. The article [http://harmattan-dev.nokia.com/docs/library/html/guide/html/Developer_Library_Developing_for_Harmattan_Using_the_device_camera.html] describes how to use the primary camera in various ways. However, access to the secondary camera is not available in QML.



== Current solution ==



The secondary camera (i.e. frontal camera) is available though the C++ API. The registration of the component in QML is possible. However, this component does not provide the methods which are in the QML Camera component [http://doc.qt.nokia.com/qtmobility-1.2/qml-camera.html].



<code lang=cpp>

#include <QGraphicsVideoItem>



FrontCameraApp::FrontCameraApp(QDeclarativeItem *parent) : QDeclarativeItem(parent)

{

   myViewfinder = new QGraphicsVideoItem(this);

   QByteArray frontCamera = QCamera::availableDevices()[1];

   myCamera = new QCamera(frontCamera);



   myCamera->setViewfinder(myViewfinder);

   myCamera->start();

}

</code>



The multimedia part from qt mobility has to be included in project.



<code>

CONFIG += mobility

MOBILITY += multimedia

</code>



Also, the FrontCameraApp object has to be registered for QML.



<code cpp>

    qmlRegisterType<FrontCameraApp>("cz.vutbr.fit.pcmlich", 1, 0, "CameraFront");

</code>



The use in QML is as follows:



<code css>

import com.nokia.meego 1.0

import cz.vutbr.fit.pcmlich 1.0

// import QtMultimediaKit 1.1

Page {

  CameraFront { 

    anchors.fill: parent;

  }

/*

 // or primary camera

  Camera {

    anchors.fill: parent;

  }

*/

}

</code>



== Additional features ==



Since Qt mobility is open source, you can download the source codes from [http://qt.gitorious.org/qt-mobility]. The implementation of the Camera element is in /plugins/declarative/multimedia/qdeclarativecamera.cpp. In order to use of this class in your own project it is necessary to modify its code to work with secondary camera as follows: 



<code cpp>

QDeclarativeCamera::QDeclarativeCamera(QDeclarativeItem *parent) :

    QDeclarativeItem(parent),

    m_camera(0),

    m_viewfinderItem(0),

    m_imageSettingsChanged(false),

    m_pendingState(ActiveState),

    m_isStateSet(false)

{

//    m_camera = new QCamera(this); // remove this line

   QByteArray frontCamera = QCamera::availableDevices()[1]; // add this line

   m_Camera = new QCamera(frontCamera); // add this line

    ...

}

</code>



Next, it is necessary to add included private header files to your project.

<code cpp>

#include "qdeclarativecamera_p.h"

#include "qdeclarativecamerapreviewprovider_p.h"

</code>



There could be a conflict in the class names QDeclarativeCamera and other problems, so it is recommended to perform refactoring of QDeclarativeCamera class. Finally, the modified class is registered into QML, as is described in the previous section.



== Problems ==



The image from the secondary camera could be confusing to the user. Therefore it is appropriate to flip it. 



<code css>

        transform: Rotation { origin.x: frontcam.width/2; origin.y: frontcam.height/2; axis { x: 0; y: 1; z: 0 } angle: 180  }

</code>



The primary and secondary cameras cannot be opened at same time.



== Summary ==



After these modifications, we have a QML component for the secondary camera which allows us modify white balance mode, exposure compensation, and other configuration of the secondary camera. It is also possible to capture images and monitor camera states. This solution is only a workaround, since the Qt Mobility is not providing a suitable interface for the secondary camera. All mentioned components are available in the attached file [FIXME]

Secondary camera in QML - Revision history

Hamishwillee: Text replace - "Category:Multimedia" to ""

Hamishwillee: Text replace - "" to ""

Hamishwillee: Hamishwillee - Subedit

Hamishwillee: Hamishwillee - Bot update - Fix ArticleMetaData

Hamishwillee: Text replace - "Category:MeeGo" to "Category:MeeGo Harmattan"

Chintandave er: Chintandave er - updated article metadata

Xmlich02: Xmlich02 -

Xmlich02: Xmlich02 -

Xmlich02: Xmlich02 -

Xmlich02: Xmlich02 -

Hamishwillee: Text replace - "`" to ""`