CameraFocus QML Type

An interface for focus related camera settings. 更多...

import 语句：

import QtMultimedia 5.8

所有成员列表，包括继承成员

特性

customFocusPoint : point
focusMode : enumeration
focusPointMode : enumeration
focusZones : list<focusZone>

方法

bool isFocusModeSupported ( mode )
bool isFocusPointModeSupported ( mode )

详细描述

This type allows control over manual and automatic focus settings, including information about any parts of the camera frame that are selected for autofocusing.

It should not be constructed separately, instead the focus property of a Camera should be used.

Item {
    width: 640
    height: 360
    Camera {
        id: camera
        focus {
            focusMode: Camera.FocusMacro
            focusPointMode: Camera.FocusPointCustom
            customFocusPoint: Qt.point(0.2, 0.2) // Focus relative to top-left corner
        }
    }
    VideoOutput {
        source: camera
        anchors.fill: parent
    }
}

特性文档编制

customFocusPoint : point

This property holds the position of custom focus point, in relative frame coordinates: QPointF (0,0) points to the left top frame point, QPointF (0.5,0.5) points to the frame center.

Custom focus point is used only in FocusPointCustom focus mode.

focusMode : enumeration

This property holds the current camera focus mode, which can be one of the following values:

值	描述
FocusManual	Manual or fixed focus mode.
FocusHyperfocal	Focus to hyperfocal distance, with the maximum depth of field achieved. All objects at distances from half of this distance out to infinity will be acceptably sharp.
FocusInfinity	Focus strictly to infinity.
FocusAuto	One-shot auto focus mode.
FocusContinuous	Continuous auto focus mode.
FocusMacro	One shot auto focus to objects close to camera.

It's possible to combine multiple Camera::FocusMode values, for example Camera.FocusMacro + Camera.FocusContinuous.

In automatic focusing modes, the focusPointMode 特性和 focusZones property provide information and control over how automatic focusing is performed.

focusPointMode : enumeration

This property holds the current camera focus point mode. It is used in automatic focusing modes to determine what to focus on. If the current focus point mode is Camera.FocusPointCustom ， customFocusPoint property allows you to specify which part of the frame to focus on.

The property can take one of the following values:

值	描述
FocusPointAuto	Automatically select one or multiple focus points.
FocusPointCenter	Focus to the frame center.
FocusPointFaceDetection	Focus on faces in the frame.
FocusPointCustom	Focus to the custom point, defined by the customFocusPoint 特性。

focusZones : list < focusZone >

This property holds the list of current camera focus zones, each including area specified in the same coordinates as customFocusPoint , and zone status as one of the following values:

值	描述
Camera.FocusAreaUnused	This focus point area is currently unused in autofocusing.
Camera.FocusAreaSelected	This focus point area is used in autofocusing, but is not in focus.
Camera.FocusAreaFocused	This focus point is used in autofocusing, and is in focus.

VideoOutput {
    id: viewfinder
    source: camera
    //display focus areas on camera viewfinder:
    Repeater {
          model: camera.focus.focusZones
          Rectangle {
              border {
                  width: 2
                  color: status == Camera.FocusAreaFocused ? "green" : "white"
              }
              color: "transparent"
              // Map from the relative, normalized frame coordinates
              property variant mappedRect: viewfinder.mapNormalizedRectToItem(area);
              x: mappedRect.x
              y: mappedRect.y
              width: mappedRect.width
              height: mappedRect.height
          }
    }
}

方法文档编制

bool isFocusModeSupported ( mode ) const

返回 true 若供给 mode is a supported focus mode, and false otherwise.

bool isFocusPointModeSupported ( mode ) const

返回 true 若供给 mode is a supported focus point mode, and false otherwise.