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/****************************************************************************
**
** Copyright (C) 2013 Digia Plc and/or its subsidiary(-ies).
** Contact: http://www.qt-project.org/legal
**
** This file is part of the documentation of the Qt Toolkit.
**
** $QT_BEGIN_LICENSE:FDL$
** Commercial License Usage
** Licensees holding valid commercial Qt licenses may use this file in
** accordance with the commercial license agreement provided with the
** Software or, alternatively, in accordance with the terms contained in
** a written agreement between you and Digia. For licensing terms and
** conditions see http://qt.digia.com/licensing. For further information
** use the contact form at http://qt.digia.com/contact-us.
**
** GNU Free Documentation License Usage
** Alternatively, this file may be used under the terms of the GNU Free
** Documentation License version 1.3 as published by the Free Software
** Foundation and appearing in the file included in the packaging of
** this file. Please review the following information to ensure
** the GNU Free Documentation License version 1.3 requirements
** will be met: http://www.gnu.org/copyleft/fdl.html.
** $QT_END_LICENSE$
**
****************************************************************************/
/*!
\example camera
\title Camera Example
\ingroup multimedia_examples
\brief The Camera Example shows how to use the API to capture a still image
or video.
The Camera Example demonstrates how you can use Qt Multimedia to implement
some basic Camera functionality to take still images and record video clips
with audio.
A Camera class is created that will act as our Camera. It has a user interface,
control functions, setting values and a means of defining the location where
the image or video clip is to be saved. It will also store the image and video
settings.
The Camera class contains an instance of \l {QCamera}, the API class interface to
the hardware. It also has an instance of \l {QCameraImageCapture} to take still images
and an instance of \l {QMediaRecorder} to record video. It also contains the user
interface object.
The Camera constructor does some basic initialization. The camera object is
set to '0', the user interface is initialized and UI signal are connected to
slots that react to the triggering event. However, most of the work is done when
the \e{setCamera()} function is called, passing in a \l {QByteArray}.
\e{setCamera()} sets up various connections between the user interface and the functionality
of the Camera class using signals and slots. It also instantiates and initializes the \l {QCamera},
\l {QCameraImageCapture} and \l {QMediaRecorder} objects mentioned above. The still
and video recording visual tabs are enabled and finally the
\l {QCamera::start()}{start()} function of the \l{QCamera} object is called.
Now that the camera is ready for user commands it waits for a suitable event.
Such an event will be the key press of either the \l {Qt::Key_CameraFocus} or
\l {Qt::Key_Camera} buttons on the application window. Camera focus will
simply display the viewfinder and lock the camera settings. Key_Camera will
either call \e{takeImage()} if the \l {QCamera::captureMode()}{captureMode()}
is QCamera::CaptureStillImage, or if the capture mode is for video then one
of two actions will occur. If the recording state shows that we are currently
recording then the \e{stop()} function is called resulting in a call to
\l {QCamera::stop()}, whereas if we are not recording then a video recording
is started with a call to \l {QMediaRecorder::record()}.
\image camera-example.png
*/
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