Qt 5.8 | Qt Multimedia | QML Types | CameraExposure QML Type

Qt 5.8.0 Reference Documentation

# CameraExposure QML Type

An interface for exposure related camera settings. More...

Import Statement: | import QtMultimedia 5.8

- List of all members, including inherited members

## Properties

- aperture : real
- exposureCompensation : real
- exposureMode : enumeration
- iso : int
- manualAperture : real
- manualIso : real
- manualShutterSpeed : real
- meteringMode : enumeration
- shutterSpeed : real
- spotMeteringPoint : QPointF

## Methods

- setAutoAperture()
- setAutoIsoSensitivity()
- setAutoShutterSpeed()

## Detailed Description

CameraExposure allows you to adjust exposure related settings like aperture and shutter speed, metering and ISO speed.

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

      Camera {
          id: camera

          exposure.exposureCompensation: -1.0
          exposure.exposureMode: Camera.ExposurePortrait
      }

Several settings have both an automatic and a manual mode. In the automatic modes the camera software itself will decide what a reasonable setting is, but in most cases these settings can be overridden with a specific manual setting.

For example, to select automatic shutter speed selection:

      camera.exposure.setAutoShutterSpeed()

Or for a specific shutter speed:

      camera.exposure.manualShutterSpeed = 0.01 // 10ms

You can only choose one or the other mode.

## Property Documentation

aperture : real

This property holds the current lens aperture as an F number (the ratio of the focal length to effective aperture diameter).

See also manualAperture and setAutoAperture().

exposureCompensation : real

This property holds the adjustment value for the automatically calculated exposure. The value is in EV units.

exposureMode : enumeration

This property holds the camera exposure mode.

The mode can be one of the following:

Value | Description
--- | ---
Camera.ExposureManual | Manual mode.
Camera.ExposureAuto | Automatic mode.
Camera.ExposureNight | Night mode.
Camera.ExposureBacklight | Backlight exposure mode.
Camera.ExposureSpotlight | Spotlight exposure mode.
Camera.ExposureSports | Spots exposure mode.
Camera.ExposureSnow | Snow exposure mode.
Camera.ExposureBeach | Beach exposure mode.
Camera.ExposureLargeAperture | Use larger aperture with small depth of field.
Camera.ExposureSmallAperture | Use smaller aperture.
Camera.ExposurePortrait | Portrait exposure mode.
Camera.ExposureAction | Action exposure mode. Since 5.5
Camera.ExposureLandscape | Landscape exposure mode. Since 5.5
Camera.ExposureNightPortrait | Night portrait exposure mode. Since 5.5
Camera.ExposureTheatre | Theatre exposure mode. Since 5.5
Camera.ExposureSunset | Sunset exposure mode. Since 5.5
Camera.ExposureSteadyPhoto | Steady photo exposure mode. Since 5.5
Camera.ExposureFireworks | Fireworks exposure mode. Since 5.5
Camera.ExposureParty | Party exposure mode. Since 5.5
Camera.ExposureCandlelight | Candlelight exposure mode. Since 5.5
Camera.ExposureBarcode | Barcode exposure mode. Since 5.5
Camera.ExposureModeVendor | The base value for device specific exposure modes.

iso : int

This property holds the sensor's ISO sensitivity value.

manualAperture : real

This property holds the aperture (F number) value for capturing photos.

If the value is less than zero, the camera automatically determines an appropriate aperture value.

aperture, setAutoAperture()

manualIso : real

This property holds the ISO settings for capturing photos.

If a negative value is specified, the camera will automatically determine an appropriate value.

See also iso and setAutoIsoSensitivity().

manualShutterSpeed : real

This property holds the shutter speed value (in seconds). If the value is less than zero, the camera automatically determines an appropriate shutter speed.

shutterSpeed, setAutoShutterSpeed()

meteringMode : enumeration

This property holds the camera metering mode (how exposure is balanced).

The mode can be one of the following:

Value | Description
--- | ---
Camera.MeteringMatrix | A matrix of sample points is used to measure exposure.
Camera.MeteringAverage | An average is used to measure exposure.
Camera.MeteringSpot | A specific location (spotMeteringPoint) is used to measure exposure.

shutterSpeed : real

This property holds the camera's current shutter speed value in seconds. To affect the shutter speed you can use the manualShutterSpeed property and setAutoShutterSpeed().

spotMeteringPoint : QPointF

The property holds the frame coordinates of the point to use for exposure metering. This point is only used in spot metering mode, and it typically defaults to the center `(0.5, 0.5)`.

## Method Documentation

setAutoAperture()

Turn on auto aperture selection. The manual aperture value is reset to -1.0

setAutoIsoSensitivity()

Turn on auto ISO sensitivity selection. The manual ISO value is reset to -1.

setAutoShutterSpeed()

Turn on auto shutter speed selection. The manual shutter speed value is reset to -1.0