Class (MakerNoteHuaweiMetadata)

MakerNoteHuaweiMetadata implements Metadata

Photo metadata from Huawei cameras.

NOTE

The initial APIs of this module are supported since API version 23. Newly added APIs will be marked with a superscript to indicate their earliest API version.

Modules to Import

import { image } from '@kit.ImageKit';

Properties

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

System capability: SystemCapability.Multimedia.Image.Core

Name	Type	Read-Only	Optional	Description
isXmageSupported	boolean	No	Yes	Whether XMAGE is supported. true indicates yes; false indicates no.
xmageWatermarkMode	number	No	Yes	XMAGE watermark mode. For details, see Constants.
xmageLeft	number	No	Yes	Horizontal coordinate of the left boundary of the effective content area (excluding the watermark coverage area) on the original image, relative to the top-left origin of the image. The unit is px.
xmageTop	number	No	Yes	Vertical coordinate of the top boundary of the effective content area (excluding the watermark coverage area) on the original image, relative to the top-left origin of the image. The unit is px.
xmageRight	number	No	Yes	Horizontal coordinate of the right boundary of the effective content area (excluding the watermark coverage area) on the original image, relative to the top-left origin of the image. The unit is px.
xmageBottom	number	No	Yes	Vertical coordinate of the bottom boundary of the effective content area (excluding the watermark coverage area) on the original image, relative to the top-left origin of the image. The unit is px.
xmageColorMode	XmageColorMode	No	Yes	XMAGE color mode.
isCloudEnhanced	boolean	No	Yes	Whether the image has been cloud-enhanced. true indicates yes; false indicates no.
cloudLabel	string	No	Yes	Cloud enhancement label.
isWindSnapshot	boolean	No	Yes	Whether the wind snapshot mode is used. true indicates yes; false indicates no. This mode is a specialized photography mode designed for capturing fast-moving subjects or scenes prone to blurring, such as in windy conditions or when photographing moving objects.
sceneVersion	number	No	Yes	Version number of the scene recognition algorithm.
sceneFoodConfidence	number	No	Yes	Capture scene: food confidence.
sceneStageConfidence	number	No	Yes	Capture scene: stage performance confidence.
sceneBlueSkyConfidence	number	No	Yes	Capture scene: blue sky confidence.
sceneGreenPlantConfidence	number	No	Yes	Capture scene: green plant confidence.
sceneBeachConfidence	number	No	Yes	Capture scene: beach confidence.
sceneSnowConfidence	number	No	Yes	Capture scene: snow confidence.
sceneSunsetConfidence	number	No	Yes	Capture scene: sunset confidence.
sceneFlowersConfidence	number	No	Yes	Capture scene: flower confidence.
sceneNightConfidence	number	No	Yes	Capture scene: night scene confidence.
sceneTextConfidence	number	No	Yes	Capture scene: text confidence.
faceCount	number	No	Yes	Number of faces.
faceConfidences	number[]	No	Yes	Confidences of a specified number of faces.
faceSmileScores	number[]	No	Yes	Smile scores of a specified number of faces.
captureMode	number	No	Yes	Capture mode.
burstNumber	number	No	Yes	Number of burst shots.
isFrontCamera	boolean	No	Yes	Whether to use the front camera. true indicates yes; false indicates no.
rollAngle	number	No	Yes	Horizontal pan angle.
pitchAngle	number	No	Yes	Pitch angle.
physicalAperture	number	No	Yes	Physical aperture, in fNumber.
focusMode	FocusMode	No	Yes	Lens focus control policy, which determines how the camera adjusts the focal length.

createInstance

static createInstance(): MakerNoteHuaweiMetadata

Returns an empty MakerNoteHuaweiMetadata instance.

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

System capability: SystemCapability.Multimedia.Image.Core

Returns:

Type	Description
MakerNoteHuaweiMetadata	Empty MakerNoteHuaweiMetadata instance.

Example:

async function makerNoteHuaweiCreateInstance(context: Context) {
  let makerNoteHuaweiMetadata = image.MakerNoteHuaweiMetadata.createInstance();
  if (makerNoteHuaweiMetadata != undefined) {
    console.info("createInstance success");
  }
}

getProperties

getProperties(key: Array<string>): Promise<Record<string, string | null>>

Obtains image property values. This API returns the result asynchronously through a promise.

For details about the properties, see PropertyKey.

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

System capability: SystemCapability.Multimedia.Image.Core

Parameters:

Name	Type	Mandatory	Description
key	Array<string>	Yes	Property names.

Returns:

Type	Description
Promise<Record<string, string | null>>	Promise used to return the property values. If the operation fails, an error code is returned.

Error codes:

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

Error Code	Error Message
7600202	Unsupported metadata. Possible causes: unsupported metadata type.

Example:

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

function getFileFd(context: Context): number | undefined {
  const filePath: string = context.cacheDir + '/exif.jpg';  // An image containing Exif metadata is required.
  const file: fileIo.File = fileIo.openSync(filePath, fileIo.OpenMode.READ_WRITE);
  const fd: number = file?.fd;
  return fd;
}

async function makerNoteHuaweiGetProperties(context: Context) {
  let fd = getFileFd(context);
  let imageSource = image.createImageSource(fd);
  let metaData = await imageSource.readImageMetadata(["HwMnoteIsXmageSupported", "HwMnoteXmageMode"]);
  if (metaData != undefined && metaData.makerNoteHuaweiMetadata != undefined) {
    await metaData.makerNoteHuaweiMetadata.getProperties(["HwMnoteIsXmageSupported", "HwMnoteXmageMode"]).then((data) => {
      console.info('Get properties ',JSON.stringify(data));
    }).catch((error: BusinessError) => {
      console.error(`Get properties failed error.code is ${error.code}, error.message is ${error.message}`);
    });
  } else {
    console.error('Metadata is null.');
  }
}

setProperties

setProperties(records: Record<string, string | null>): Promise<void>

Sets the values of specified properties in image metadata in batches. This API returns the result asynchronously through a promise.

For details about the properties, see PropertyKey.

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

System capability: SystemCapability.Multimedia.Image.Core

Parameters:

Name	Type	Mandatory	Description
records	Record<string, string | null>	Yes	Array containing key-value pairs representing properties and their corresponding values of the MakerNoteHuaweiMetadata object to be modified.

Returns:

Type	Description
Promise<void>	Promise that returns no value.

Error codes:

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

Error Code	Error Message
7600202	Unsupported metadata. Possible causes: unsupported metadata type.

Example:

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

function getFileFd(context: Context): number | undefined {
  const filePath: string = context.cacheDir + '/exif.jpg';  // An image containing Exif metadata is required.
  const file: fileIo.File = fileIo.openSync(filePath, fileIo.OpenMode.READ_WRITE);
  const fd: number = file?.fd;
  return fd;
}

async function makerNoteHuaweiSetProperties(context: Context) {
  let fd = getFileFd(context);
  let imageSource = image.createImageSource(fd);
  let metaData = await imageSource.readImageMetadata(["HwMnoteIsXmageSupported", "HwMnoteXmageMode"]);
  if (metaData != undefined && metaData.makerNoteHuaweiMetadata != undefined) {
    let setkey: Record<string, string | null> = {
      "HwMnoteIsXmageSupported": "1",
      "HwMnoteXmageMode": "9"
    };
    await metaData.makerNoteHuaweiMetadata.setProperties(setkey).then(async () => {
      console.info('Set properties success.');
    }).catch((error: BusinessError) => {
      console.error(`Failed to set metadata Properties. code is ${error.code}, message is ${error.message}`);
    })
  } else {
    console.error('metadata is null. ');
  }
}

getAllProperties

getAllProperties(): Promise<Record<string, string | null>>

Obtains all properties and their values from the image metadata. This API returns the result asynchronously through a promise.

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

System capability: SystemCapability.Multimedia.Image.Core

Returns:

Type	Description
Promise<Record<string, string | null>>	Promise used to return all key-value pairs defined in the metadata.

Example:

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

function getFileFd(context: Context): number | undefined {
  const filePath: string = context.cacheDir + '/exif.jpg';  // An image containing Exif metadata is required.
  const file: fileIo.File = fileIo.openSync(filePath, fileIo.OpenMode.READ_WRITE);
  const fd: number = file?.fd;
  return fd;
}

async function makerNoteHuaweiGetAllProperties(context: Context) {
  let fd = getFileFd(context);
  let imageSource = image.createImageSource(fd);
  let metaData = await imageSource.readImageMetadata(["HwMnoteIsXmageSupported", "HwMnoteXmageMode"]);
  if (metaData != undefined && metaData.makerNoteHuaweiMetadata != undefined) {
    await metaData.makerNoteHuaweiMetadata.getAllProperties().then((data) => {
      const count = Object.keys(data).length;
      console.info(`Get metadata all properties: ${data}`);
    }).catch((error: BusinessError) => {
      console.error(`Get metadata all properties failed error.code is ${error.code}, error.message is ${error.message}`);
    });
  } else {
    console.error('Metadata is null.');
  }
}

clone

clone(): Promise<MakerNoteHuaweiMetadata>

Clones MakerNoteHuaweiMetadata metadata. This API returns the result asynchronously through a promise.

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

System capability: SystemCapability.Multimedia.Image.Core

Returns:

Type	Description
Promise<MakerNoteHuaweiMetadata>	Promise used to return the MakerNoteHuaweiMetadata metadata instance if metadata is successfully obtained.

Example:

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

function getFileFd(context: Context): number | undefined {
  const filePath: string = context.cacheDir + '/exif.jpg';  // An image containing Exif metadata is required.
  const file: fileIo.File = fileIo.openSync(filePath, fileIo.OpenMode.READ_WRITE);
  const fd: number = file?.fd;
  return fd;
}

async function makerNoteHuaweiClone(context: Context) {
  let fd = getFileFd(context);
  let imageSource = image.createImageSource(fd);
  let metaData = await imageSource.readImageMetadata(["HwMnoteIsXmageSupported", "HwMnoteXmageMode"]);
  if (metaData != undefined && metaData.makerNoteHuaweiMetadata != undefined) {
    let new_metadata = await metaData.makerNoteHuaweiMetadata.clone();
    new_metadata.getProperties(["HwMnoteIsXmageSupported"]).then((data1) => {
      console.info(`Clone new_metadata and get Properties: ${data1}`);
    }).catch((err: BusinessError) => {
      console.error(`Clone new_metadata failed, error : ${err}`);
    });
  } else {
    console.error('Metadata is null.');
  }
}

getBlob

getBlob(): Promise<ArrayBuffer>

Obtains the metadata in binary format. This API returns the result asynchronously through a promise.

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

System capability: SystemCapability.Multimedia.Image.Core

Returns:

Type	Description
Promise<ArrayBuffer>	Promise used to return the binary data of the metadata.

Example:

import { fileIo } from '@kit.CoreFileKit';

function getFileFd(context: Context): number | undefined {
  const filePath: string = context.cacheDir + '/exif.jpg';  // An image containing Exif metadata is required.
  const file: fileIo.File = fileIo.openSync(filePath, fileIo.OpenMode.READ_WRITE);
  const fd: number = file?.fd;
  return fd;
}

async function makerNoteHuaweiGetBlob(context: Context) {
  let fd = getFileFd(context);
  let imageSource = image.createImageSource(fd);
  let metaData = await imageSource.readImageMetadata(["HwMnoteIsXmageSupported", "HwMnoteXmageMode"]);
  if (metaData != undefined && metaData.makerNoteHuaweiMetadata != undefined) {
    let blob = await metaData.makerNoteHuaweiMetadata.getBlob();
    if (blob != undefined) {
      console.info("get blob success");
    }
  }
}

setBlob

setBlob(blob: ArrayBuffer): Promise<void>

Replaces the current metadata with binary data. This API returns the result asynchronously through a promise.

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

System capability: SystemCapability.Multimedia.Image.Core

Parameters:

Name	Type	Mandatory	Description
blob	ArrayBuffer	Yes	Binary data used to replace the metadata.

Returns:

Type	Description
Promise<void>	Promise that returns no value.

Error codes:

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

Error Code	Error Message
7600206	Invalid parameter. Possible causes: The blob is empty or has a length of 0.

Example:

import { fileIo } from '@kit.CoreFileKit';

function getFileFd(context: Context): number | undefined {
  const filePath: string = context.cacheDir + '/exif.jpg';  // An image containing Exif metadata is required.
  const file: fileIo.File = fileIo.openSync(filePath, fileIo.OpenMode.READ_WRITE);
  const fd: number = file?.fd;
  return fd;
}

async function makerNoteHuaweiSetBlob(context: Context) {
  let fd = getFileFd(context);
  let imageSource = image.createImageSource(fd);
  let metaData = await imageSource.readImageMetadata(["HwMnoteIsXmageSupported", "HwMnoteXmageMode"]);
  if (metaData != undefined && metaData.makerNoteHuaweiMetadata != undefined) {
    let blob = await metaData.makerNoteHuaweiMetadata.getBlob();
    if (blob != undefined) {
      console.info("get blob success");
      metaData.makerNoteHuaweiMetadata.setBlob(blob);
    }
    let new_blob = metaData.makerNoteHuaweiMetadata.getBlob();
    if (new_blob != undefined) {
      console.info("new_blob is not undefined");
    }
  }
}