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QCameraFocusZone Class

The QCameraFocusZone class provides information on zones used for autofocusing a camera. More...

Header: #include <QCameraFocusZone>
qmake: QT += multimedia

Public Types

enum FocusZoneStatus { Invalid, Unused, Selected, Focused }

Public Functions

QCameraFocusZone(const QCameraFocusZone &other)
QCameraFocusZone &operator=(const QCameraFocusZone &other)
~QCameraFocusZone()
QRectF area() const
bool isValid() const
QCameraFocusZone::FocusZoneStatus status() const
bool operator!=(const QCameraFocusZone &other) const
bool operator==(const QCameraFocusZone &other) const

Detailed Description

For cameras that support autofocusing, in order for a camera to autofocus on part of a sensor frame, it considers different zones within the frame. Which zones to use, and where the zones are located vary between different cameras.

This class exposes what zones are used by a particular camera, and a list of the zones can be retrieved by a QCameraFocus instance.

You can use this information to present visual feedback - for example, drawing rectangles around areas of the camera frame that are in focus, or changing the color of a zone as it comes into focus.

focus->setFocusPointMode(QCameraFocus::FocusPointAuto);
const QList<QCameraFocusZone> zones = focus->focusZones();
for (const QCameraFocusZone &zone : zones) {
    if (zone.status() == QCameraFocusZone::Focused) {
        // Draw a green box at zone.area()
    } else if (zone.status() == QCameraFocusZone::Selected) {
        // This area is selected for autofocusing, but is not in focus
        // Draw a yellow box at zone.area()
    }
}

See also QCameraFocus.

Member Type Documentation

enum QCameraFocusZone::FocusZoneStatus

ConstantValueDescription
QCameraFocusZone::Invalid0This zone is not valid
QCameraFocusZone::Unused1This zone may be used for autofocusing, but is not currently.
QCameraFocusZone::Selected2This zone is currently being used for autofocusing, but is not in focus.
QCameraFocusZone::Focused3This zone is being used for autofocusing and is currently in focus.

Member Function Documentation

QCameraFocusZone::QCameraFocusZone(const QCameraFocusZone &other)

Creates a new QCameraFocusZone as a copy of other.

QCameraFocusZone &QCameraFocusZone::operator=(const QCameraFocusZone &other)

Assigns other to this QCameraFocusZone.

QCameraFocusZone::~QCameraFocusZone()

Destroys this QCameraFocusZone.

QRectF QCameraFocusZone::area() const

Returns the area of the camera frame that this focus zone encompasses.

Coordinates are in frame relative coordinates - QPointF(0,0) is the top left of the frame, and QPointF(1,1) is the bottom right.

bool QCameraFocusZone::isValid() const

Returns true if this focus zone has a valid area and status.

QCameraFocusZone::FocusZoneStatus QCameraFocusZone::status() const

Returns the current status of this focus zone.

bool QCameraFocusZone::operator!=(const QCameraFocusZone &other) const

Returns true if this focus zone is not the same as other.

bool QCameraFocusZone::operator==(const QCameraFocusZone &other) const

Returns true if this focus zone is the same as other.

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