qquickimagecapture.cpp

Go to the documentation of this file.

// Copyright (C) 2016 The Qt Company Ltd.
// SPDX-License-Identifier: LicenseRef-Qt-Commercial OR LGPL-3.0-only OR GPL-2.0-only OR GPL-3.0-only
 
#include "qquickimagecapture_p.h"
#include "qquickimagepreviewprovider_p.h"
 
#include <QtCore/qurl.h>
 
QT_BEGIN_NAMESPACE
 
/*!
    \qmltype ImageCapture
    \nativetype QQuickImageCapture
    \brief An interface for capturing camera images.
    \ingroup multimedia_qml
    \inqmlmodule QtMultimedia
    \ingroup camera_qml
 
    This type allows you to capture still images and be notified when they
    are available or saved to disk.
 
    \qml
    Item {
        width: 640
        height: 360
 
        CaptureSession {
            imageCapture : ImageCapture {
                id: imageCapture
            }
            camera: Camera {
                id: camera
            }
 
            videoOutput: videoOutput
        }
        VideoOutput {
            id: videoOutput
            anchors.fill: parent
 
            MouseArea {
                anchors.fill: parent;
                onClicked: imageCapture.capture();
            }
        }
 
        Image {
            id: photoPreview
            source: imageCapture.preview // always shows the last captured image
        }
    }
    \endqml
 
*/
 
QQuickImageCapture::QQuickImageCapture(QObject *parent)
    : QImageCapture(parent)
{
    connect(this, &QImageCapture::imageCaptured, this, &QQuickImageCapture::_q_imageCaptured);
}
 
QQuickImageCapture::~QQuickImageCapture()
{
    QQuickImagePreviewProvider::cleanupInstance(m_instanceId);
}
 
/*!
    \qmlproperty bool QtMultimedia::ImageCapture::readyForCapture
 
    This property holds a bool value indicating whether the camera
    is ready to capture photos or not.
 
    Calling capture() or captureToFile() while \e ready is \c false is not permitted and
    results in an error.
*/
 
/*!
    \qmlproperty string QtMultimedia::ImageCapture::preview
 
    This property holds a url to the latest captured image. It can be connected to the
    source property of an \l Image element to show the last captured image.
 
    \qml
    CaptureSession {
        camera: Camera {}
        imageCapture: ImageCapture {
            id: capture
        }
    }
    Image {
        source: capture.preview
    }
    \endqml
 
    \sa saveToFile
*/
 
/*!
    \qmlmethod int QtMultimedia::ImageCapture::capture()
 
    Start image capture.  The \l imageCaptured and \l imageSaved signals will
    be emitted when the capture is complete.
 
    The captured image will be available through the preview property that can be
    used as the source for a QML Image item. The saveToFile() method can then be used
    save the image.
 
    Camera saves all the capture parameters like exposure settings or
    image processing parameters, so changes to camera parameters after
    capture() is called do not affect previous capture requests.
 
    capture() returns the capture requestId parameter, used with
    imageExposed(), imageCaptured(), imageMetadataAvailable() and imageSaved() signals.
 
    \sa readyForCapture, preview
*/
 
/*!
    \qmlmethod int QtMultimedia::ImageCapture::captureToFile(location)
 
    Does the same as capture() but additionally automatically saves the
    captured image to the specified \a location. Returns the capture
    requestId parameter.
 
    \sa capture()
*/
 
QString QQuickImageCapture::preview() const
{
    return m_capturedImagePath;
}
 
/*!
    \qmlmethod void QtMultimedia::ImageCapture::saveToFile(location)
 
    Saves the last captured image to \a location.
 
    \sa capture, preview
*/
void QQuickImageCapture::saveToFile(const QUrl &location) const
{
    m_lastImage.save(location.toLocalFile());
}
 
void QQuickImageCapture::_q_imageCaptured(int id, const QImage &preview)
{
    QString previewId =
            QStringLiteral("preview_%1_%2").arg(m_instanceId.toString(QUuid::Id128)).arg(id);
    QQuickImagePreviewProvider::registerPreview(m_instanceId, previewId, preview);
    m_capturedImagePath = QStringLiteral("image://QtMultimediaCameraPreviewImageProvider/%2").arg(previewId);
    m_lastImage = preview;
    emit previewChanged();
}
 
/*!
    \qmlsignal QtMultimedia::ImageCapture::errorOccurred(id, error, errorString)
 
    This signal is emitted when an error occurs during capture with requested \a id.
    \a error is an enumeration of type ImageCapture::Error.
    A descriptive message is available in \a errorString.
 
    \sa error errorString
*/
 
/*!
    \qmlsignal QtMultimedia::ImageCapture::imageCaptured(requestId, preview)
 
    This signal is emitted when an image with requested id \a requestId has been captured
    but not yet saved to the filesystem.  The \a preview
    parameter is the captured image.
 
    \sa imageSaved, preview
*/
 
/*!
    \qmlsignal QtMultimedia::ImageCapture::imageSaved(id, fileName)
 
    This signal is emitted after the image with requested \a id has been written to the filesystem.
    The \a fileName is a local file path, not a URL.
 
    \sa imageCaptured
*/
 
 
/*!
    \qmlsignal QtMultimedia::ImageCapture::imageMetadataAvailable(id, metaData)
 
    This signal is emitted when the image with requested \a id has new \a metaData.
 
    \sa imageCaptured
*/
 
 
QT_END_NAMESPACE
 
#include "moc_qquickimagecapture_p.cpp"