harmony-utils 之 ImageUtil，图片相关工具类

2025-06-25
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harmony-utils 之 ImageUtil，图片相关工具类

harmony-utils 简介与说明

harmony-utils 一款功能丰富且极易上手的 HarmonyOS 工具库，借助众多实用工具类，致力于助力开发者迅速构建鸿蒙应用。其封装的工具涵盖了 APP、设备、屏幕、授权、通知、线程间通信、弹框、吐司、生物认证、用户首选项、拍照、相册、扫码、文件、日志，异常捕获、字符、字符串、数字、集合、日期、随机、base64、加密、解密、JSON 等一系列的功能和操作，能够满足各种不同的开发需求。

picker_utils 是 harmony-utils 拆分出来的一个子库，包含 PickerUtil、PhotoHelper、ScanUtil。

下载安装

ohpm i @pura/harmony-utils

ohpm i @pura/picker_utils

  //全局初始化方法，在UIAbility的onCreate方法中初始化 AppUtil.init()  onCreate(want: Want, launchParam: AbilityConstant.LaunchParam): void {    AppUtil.init(this.context);  }

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API 方法与使用

base64ToPixelMap 图片 base64 字符串转 PixelMap

 let base64str = "data:image/png;base64,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"; let pixelMap = await ImageUtil.base64ToPixelMap(base64str);

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pixelMapToBase64Str PixelMap 转图片 base64 字符串

  let pixelMap = await ImageUtil.getPixelMapFromMedia($r("app.media.test_as3"));  let base64Str = await ImageUtil.pixelMapToBase64Str(pixelMap);

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savePixelMap 保存 pixelMap 到本地

let pixelMap = await ImageUtil.getPixelMapFromMedia($r("app.media.test_as4"));let filePath = await ImageUtil.savePixelMap(pixelMap, FileUtil.getFilesDirPath(""), "测试图片.png");

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saveImageSource 保存 ImageSource 到本地

let filePath = "这里是图片地址"let imageSource = await ImageUtil.createImageSource(filePath);ImageUtil.saveImageSource(imageSource, FileUtil.getFilesDirPath(""), `MZ_${DateUtil.getTodayStr()}.png`)  .then(() => {    ToastUtil.showToast("保存成功");  });

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createImageSource 创建图片源实例

let filePath = "这里是图片地址"let imageSource = await ImageUtil.createImageSource(filePath);let pixelMap = await imageSource.createPixelMap();

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packingFromPixelMap 图片压缩或重新打包

let filePath = "这里是图片地址"let pixelMap = await ImageUtil.createImageSource(filePath).createPixelMap()let packOpts: image.PackingOption = { format: "image/png", quality: 98 }ImageUtil.packingFromPixelMap(pixelMap, packOpts).then((buff) => {  LogUtil.error("buff: " + buff.byteLength);  ToastUtil.showToast("打包成功了");});

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packingFromImageSource 图片压缩或重新打包

let filePath = "这里是图片地址"let imageSource = await ImageUtil.createImageSource(filePath);let packOpts: image.PackingOption = { format: "image/png", quality: 98 }ImageUtil.packingFromImageSource(imageSource, packOpts).then((buff) => {  LogUtil.error("buff: " + buff.byteLength);  ToastUtil.showToast("打包成功了");});

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packToFileFromPixelMap 将 PixelMap 图片源编码后直接打包进文件

let filePath = "这里是图片地址"let pixelMap = await ImageUtil.createImageSource(this.filePath).createPixelMap();let filePath = FileUtil.getFilesDirPath("", `MeiZi_${DateUtil.getTodayTime()}.png`);let file = FileUtil.openSync(filePath);let packOpts: image.PackingOption = { format: "image/png", quality: 100 }ImageUtil.packToFileFromPixelMap(pixelMap, file.fd, packOpts).then(() => {  FileUtil.closeSync(file.fd); //关闭文件  ToastUtil.showToast("图片保存成功");});

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packToFileFromImageSource 将 ImageSource 图片源编码后直接打包进文件

let filePath = "这里是图片地址"let imageSource = await ImageUtil.createImageSource(filePath);let filePath = FileUtil.getFilesDirPath("", `MeiZi_${DateUtil.getTodayTime()}.png`);let file = FileUtil.openSync(filePath);let packOpts: image.PackingOption = { format: "image/png", quality: 100 }ImageUtil.packToFileFromImageSource(imageSource, file.fd, packOpts).then(() => {  FileUtil.closeSync(file.fd); //关闭文件  ToastUtil.showToast("图片保存成功");});

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getPixelMapFromMedia 用户获取 resource 目录下的 media 中的图片 PixelMap

let pixelMap = await ImageUtil.getPixelMapFromMedia($r("app.media.test_as4"));

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compressedImage 图片压缩

let pixelMap = await ImageUtil.getPixelMapFromMedia($r("app.media.test_as5")); //原大小3.78Mlet arrayBuffer = await ImageUtil.compressedImage(pixelMap, 150);LogUtil.error("压缩后的大小：" + arrayBuffer.byteLength);PickerUtil.savePhoto(['压缩后的图片.jpeg']).then(async (uris)=>{  let uri = uris[0];  await FileUtil.writeEasy(uri,arrayBuffer,false);  ToastUtil.showToast("压缩文件保存成功");});

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compressPhoto 图片压缩，返回压缩后的图片文件路径

PhotoHelper.select({ maxSelectNumber: 1 }).then(async (uris) => {  if (uris?.length > 0) {    let uri = uris[0];    let filePath = await ImageUtil.compressPhoto(uri, 100).catch((err: BusinessError) => {      LogUtil.error("图片压缩异常：" + err.message);      return "";    }); //压缩返回路径    let oldSize = FileUtil.statSync(FileUtil.openSync(uri, fs.OpenMode.READ_ONLY).fd).size; //压缩前大小    let compressSize = FileUtil.statSync(filePath).size; //压缩后大小    this.resultStr = `压缩路径: ${filePath}\n\n压缩前大小: ${FileUtil.getFormatFileSize(oldSize)}\n压缩后大小: ${FileUtil.getFormatFileSize(compressSize)}`;    LogUtil.error(this.resultStr);  }}).catch((err: BusinessError) => {  LogUtil.error("异常信息：" + err.message);});