Interface (ManualExposure)

ManualExposure inherits from ManualExposureQuery.

Describes a manual exposure object.

NOTE

• The initial APIs of this module are supported since API version 10. Newly added APIs will be marked with a superscript to indicate their earliest API version.
• The initial APIs of this interface are supported since API version 24.

Modules to Import

import { camera } from '@kit.CameraKit';

getExposureDuration²⁴⁺

getExposureDuration(): number

Obtains the exposure duration.

Atomic service API: This API can be used in atomic services since API version 24.

System capability: SystemCapability.Multimedia.Camera.Core

Returns

Type	Description
number	Exposure duration, in microseconds.

Error Codes

For details about the error codes, see Camera Error Codes.

Error Code	Error Message
7400102	Operation not allowed, session or inputdevice maybe abnormal.
7400103	Session not config.

Example

import { BusinessError } from '@kit.BasicServicesKit';

function getExposureDuration(photoSession: camera.PhotoSession): number {
  let exposureDuration: number = 0;
  try {
    exposureDuration = photoSession.getExposureDuration();
  } catch (error) {
    // If the operation fails, error.code is returned and processed.
    let err = error as BusinessError;
    console.error(`The getExposureDuration call failed. error code: ${err.code}`);
  }
  return exposureDuration;
}

setExposureDuration²⁴⁺

setExposureDuration(exposureDuration: number): void

Sets the exposure duration.

The setting takes effect only when ExposureMode is set to EXPOSURE_MODE_MANUAL.

Atomic service API: This API can be used in atomic services since API version 24.

System capability: SystemCapability.Multimedia.Camera.Core

Parameters

Parameter	Type	Mandatory	Description
exposureDuration	number	Yes	Exposure duration, in microseconds.

Error Codes

For details about the error codes, see Camera Error Codes.

Error Code	Error Message
7400103	Session not config.

Example

import { BusinessError } from '@kit.BasicServicesKit';

function setExposureDuration(photoSession: camera.PhotoSession, exposureDuration: number): void {
  try {
    photoSession.setExposureDuration(exposureDuration);
  } catch (error) {
    // If the operation fails, error.code is returned and processed.
    let err = error as BusinessError;
    console.error(`The setExposureDuration call failed. error code: ${err.code}`);
  }
}

onExposureInfoChange²⁴⁺

onExposureInfoChange(callback: Callback<ExposureInfo>): void

Subscribes to exposure information change events. After the exposure parameters are modified, the system returns the updated exposure information.

Model restriction: This API can be used only in the stage model.

Atomic service API: This API can be used in atomic services since API version 24.

System capability: SystemCapability.Multimedia.Camera.Core

Parameters

Parameter	Type	Mandatory	Description
callback	Callback<ExposureInfo>	Yes	Callback used to obtain the exposure information.

Example

function onExposureInfoChange(photoSession: camera.PhotoSession): void {
  photoSession.onExposureInfoChange((exposureInfo: camera.ExposureInfo) => {
    console.info(`Exposure info changed, exposureTime: ${exposureInfo.exposureTime}`);
  });
}

offExposureInfoChange²⁴⁺

offExposureInfoChange(callback?: Callback<ExposureInfo>): void

Unsubscribes from exposure information change events. If you have subscribed to exposure information change events, cancel the subscription before releasing the camera object.

Model restriction: This API can be used only in the stage model.

Atomic service API: This API can be used in atomic services since API version 24.

System capability: SystemCapability.Multimedia.Camera.Core

Parameters

Parameter	Type	Mandatory	Description
callback	Callback<ExposureInfo>	No	Callback used to return the result. If this parameter is specified, the subscription to the specified event with the specified callback is canceled. (The callback object cannot be an anonymous function.) Otherwise, the subscriptions to the specified event with all the callbacks are canceled.

Example

function offExposureInfoChange(photoSession: camera.PhotoSession): void {
  photoSession.offExposureInfoChange();
}

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