降采样适配3.x

Signed-off-by: tsm <2418639820@qq.com>

entry/src/main/ets/pages/DownSamplePage.ets

@@ -0,0 +1,113 @@
+/*
+ * Copyright (C) 2024 Huawei Device Co., Ltd.
+ * Licensed under the Apache License, Version 2.0 (the 'License');
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an 'AS IS' BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+import { DownsampleStrategy, ImageKnifeComponent } from '@ohos/imageknife';
+@Entry
+@Component
+struct DownSamplePage {
+  @State message: string = 'Hello World';
+  build() {
+    Scroll() {
+      Column(){
+        ImageKnifeComponent({
+          imageKnifeOption: {
+            loadSrc: $r("app.media.jpgSample"),
+            placeholderSrc: $r("app.media.loading"),
+            errorholderSrc: $r("app.media.app_icon"),
+            downsampling: DownsampleStrategy.FIT_CENTER,
+            objectFit: ImageFit.Contain,
+            autoResize:true
+          }
+        })
+          .height(300)
+          .width(300)
+          .borderWidth(1)
+          .borderColor(Color.Pink)
+        ImageKnifeComponent({
+          imageKnifeOption: {
+            loadSrc: "http://g.hiphotos.baidu.com/image/pic/item/6d81800a19d8bc3e770bd00d868ba61ea9d345f2.jpg",
+            placeholderSrc: $r("app.media.loading"),
+            errorholderSrc: $r("app.media.app_icon"),
+            downsampling: DownsampleStrategy.AT_MOST,
+            objectFit: ImageFit.Contain,
+            autoResize:true
+          }
+        })
+          .height(300)
+          .width(300)
+          .borderWidth(1)
+          .borderColor(Color.Pink)
+        ImageKnifeComponent({
+          imageKnifeOption: {
+            loadSrc: $r("app.media.jpgSample"),
+            placeholderSrc: $r("app.media.loading"),
+            errorholderSrc: $r("app.media.app_icon"),
+            downsampling: DownsampleStrategy.AT_LEAST,
+            objectFit: ImageFit.Contain,
+            autoResize:true
+          }
+        })
+          .height(300)
+          .width(300)
+          .borderWidth(1)
+          .borderColor(Color.Pink)
+        ImageKnifeComponent({
+          imageKnifeOption: {
+            loadSrc: $r("app.media.jpgSample"),
+            placeholderSrc: $r("app.media.loading"),
+            errorholderSrc: $r("app.media.app_icon"),
+            downsampling: DownsampleStrategy.CENTER_INSIDE,
+            objectFit: ImageFit.Contain,
+            autoResize:true
+          }
+        })
+          .height(300)
+          .width(300)
+          .borderWidth(1)
+          .borderColor(Color.Pink)
+        ImageKnifeComponent({
+          imageKnifeOption: {
+            loadSrc: $r("app.media.jpgSample"),
+            placeholderSrc: $r("app.media.loading"),
+            errorholderSrc: $r("app.media.app_icon"),
+            downsampling: DownsampleStrategy.CENTER_OUTSIDE,
+            objectFit: ImageFit.Contain,
+            autoResize:true
+          }
+        })
+          .height(300)
+          .width(300)
+          .borderWidth(1)
+          .borderColor(Color.Pink)
+        ImageKnifeComponent({
+          imageKnifeOption: {
+            loadSrc: $r("app.media.jpgSample"),
+            placeholderSrc: $r("app.media.loading"),
+            errorholderSrc: $r("app.media.app_icon"),
+            downsampling: DownsampleStrategy.NONE,
+            objectFit: ImageFit.Contain,
+            autoResize:true
+          }
+        })
+          .height(300)
+          .width(300)
+          .borderWidth(1)
+          .borderColor(Color.Pink)
+      }
+
+    }
+    .height('100%')
+    .width('100%')
+  }
+}

entry/src/main/ets/pages/Index.ets

@@ -17,8 +17,6 @@ import router from '@system.router';
 @Entry
 @Component
 struct Index {
-
-
   aboutToAppear(): void {
 
   }
@@ -26,73 +24,78 @@ struct Index {
   build() {
 
     Column() {
-      Button("单个图片使用").onClick(()=>{
+      Button("单个图片使用").onClick(() => {
         router.push({
           uri: 'pages/SingleImage',
 
         });
       })
-      Button("多图 + LazyForEach").margin({top:10}).onClick(()=>{
+      Button("下采样").margin({ top: 10 }).onClick(() => {
+        router.push({
+          uri: "pages/DownSamplePage",
+        });
+      })
+      Button("多图 + LazyForEach").margin({ top: 10 }).onClick(() => {
         router.push({
           uri: 'pages/ManyPhotoShowPage',
 
         });
       })
-      Button("多图 + reuse + LazyForeach").margin({top:10}).onClick(()=>{
+      Button("多图 + reuse + LazyForeach").margin({ top: 10 }).onClick(() => {
         router.push({
           uri: 'pages/UserPage',
 
         });
       })
-      Button("长图显示").margin({top:10}).onClick(()=>{
+      Button("长图显示").margin({ top: 10 }).onClick(() => {
         router.push({
           uri: 'pages/LongImagePage',
 
         });
       })
-      Button("缩放图片").margin({top:10}).onClick(()=>{
+      Button("缩放图片").margin({ top: 10 }).onClick(() => {
         router.push({
           uri: 'pages/TransformPage',
 
         });
       })
-      Button("消息+List").margin({top:10}).onClick(()=>{
+      Button("消息+List").margin({ top: 10 }).onClick(() => {
         router.push({
           uri: 'pages/TestImageFlash',
 
         });
       })
-      Button("自定义缓存key").margin({top:10}).onClick(()=>{
+      Button("自定义缓存key").margin({ top: 10 }).onClick(() => {
         router.push({
           uri: 'pages/SignatureTestPage',
 
         });
       })
-      Button("预加载图片到文件缓存").margin({top:10}).onClick(()=>{
+      Button("预加载图片到文件缓存").margin({ top: 10 }).onClick(() => {
         router.push({
           uri: 'pages/TestPrefetchToFileCache',
 
         });
       })
-      Button("从缓存获取图片显示").margin({top:10}).onClick(()=>{
+      Button("从缓存获取图片显示").margin({ top: 10 }).onClick(() => {
         router.push({
           uri: 'pages/TestIsUrlExist',
 
         });
       })
-      Button("测试单个请求头").margin({top:10}).onClick(()=>{
+      Button("测试单个请求头").margin({ top: 10 }).onClick(() => {
         router.push({
           uri: 'pages/TestHeader',
 
         });
       })
-      Button("测试写入缓存策略").margin({top:10}).onClick(()=>{
+      Button("测试写入缓存策略").margin({ top: 10 }).onClick(() => {
         router.push({
           uri: 'pages/TestWriteCacheStage',
 
         });
       })
-      Button("图片变换").margin({top:10}).onClick(()=>{
+      Button("图片变换").margin({ top: 10 }).onClick(() => {
         router.push({
           uri: 'pages/ImageTransformation',
 
@@ -100,7 +103,7 @@ struct Index {
 
       })
 
-      Button("不同的ObjectFit").margin({top:10}).onClick(()=>{
+      Button("不同的ObjectFit").margin({ top: 10 }).onClick(() => {
         router.push({
           uri: 'pages/ObjectFitPage',
 

entry/src/main/resources/base/profile/main_pages.json

@@ -14,8 +14,9 @@
     "pages/TestHeader",
     "pages/ImageTransformation",
     "pages/ObjectFitPage",
-    "pages/TestWriteCacheStage",
     "pages/LoadStatePage",
-    "pages/TestRemoveCache"
+    "pages/TestRemoveCache",
+    "pages/TestWriteCacheStage",
+    "pages/DownSamplePage"
   ]
 }

hvigor/hvigor-config.json5

@@ -1,6 +1,7 @@
 {
   "modelVersion": "5.0.0",
   "dependencies": {
+    "@ohos/hvigor-ohos-plugin": "4.1.2"
   },
   "execution": {
     // "analyze": "default",                    /* Define the build analyze mode. Value: [ "default" | "verbose" | false ]. Default: "default" */

library/BuildProfile.ets

@@ -1,5 +1,6 @@
 export default class BuildProfile { 
-	static readonly HAR_VERSION = '3.0.0-rc.0';
+	static readonly HAR_VERSION = '3.0.0-rc.4';
 	static readonly BUILD_MODE_NAME = 'debug';
 	static readonly DEBUG = true;
+	static readonly TARGET_NAME = 'default';
 }

library/index.ets

@@ -22,4 +22,6 @@ export { BrightnessTransformation } from './src/main/ets/transform/BrightnessTra
 
 export { BlurTransformation } from './src/main/ets/transform/BlurTransformation'
 
+export { DownsampleStrategy } from './src/main/ets/downsampling/DownsampleStartegy'
+
 

library/src/main/ets/ImageKnifeDispatcher.ets

@@ -39,6 +39,9 @@ import {
   RequestJobRequest
 } from './model/ImageKnifeData'
 import { combineArrayBuffers } from './model/utils';
+import { BusinessError } from '@kit.BasicServicesKit';
+import { Downsampler } from './downsampling/Downsampler'
+import { DownsampleStrategy } from './downsampling/DownsampleStartegy';
 
 export class ImageKnifeDispatcher {
   // 最大并发
@@ -144,7 +147,12 @@ export class ImageKnifeDispatcher {
         .isFileCacheInit() ? currentRequest.imageKnifeOption.writeCacheStrategy : CacheStrategy.Memory, // 未初始化文件缓存时，不写文件缓存
       engineKey: this.engineKey,
       signature: currentRequest.imageKnifeOption.signature,
-      requestSource
+      requestSource,
+      targetWidth: currentRequest.componentWidth,
+      targetHeight: currentRequest.componentHeight,
+      downsampType: currentRequest.imageKnifeOption.downsampling,
+      autoResize:currentRequest.imageKnifeOption.autoResize
+
     }
     // 启动线程下载和解码主图
     let task = new taskpool.Task(requestJob, request)
@@ -404,7 +412,6 @@ async function requestJob(request: RequestJobRequest): Promise<RequestJobResult
     }
   }
 
-
   if (resBuf == undefined) {
     return {
       pixelMap: undefined,
@@ -418,7 +425,6 @@ async function requestJob(request: RequestJobRequest): Promise<RequestJobResult
   let typeValue = fileTypeUtil.getFileType(resBuf);
   if (typeValue === 'gif' || typeValue === 'webp') {
     let base64Help = new util.Base64Helper()
-
     let base64str = "data:image/" + typeValue + ";base64," + base64Help.encodeToStringSync(new Uint8Array(resBuf))
     return {
       pixelMap: base64str,
@@ -426,10 +432,19 @@ async function requestJob(request: RequestJobRequest): Promise<RequestJobResult
       fileKey: fileKey
     };
   }
-
+  let autoResizes = request.autoResize
   let imageSource: image.ImageSource = image.createImageSource(resBuf);
-  let decodingOptions: image.DecodingOptions = {
+  let imageInfo = await  imageSource.getImageInfo()
+  let a = new Downsampler().calculateScaling(typeValue, imageInfo.size.width, imageInfo.size.height, request.targetWidth,
+    request.targetHeight, request.downsampType,autoResizes)
+  let decodingOptions: image.DecodingOptions = request.downsampType === DownsampleStrategy.NONE ? {
     editable: true,
+  } : {
+    editable: true,
+    desiredSize: {
+      width: a.targetWidth,
+      height: a.targetHeight
+    }
   }
 
   let resPixelmap: PixelMap | undefined = undefined

library/src/main/ets/ImageKnifeOption.ets

@@ -13,14 +13,16 @@
  * limitations under the License.
  */
 import taskpool from '@ohos.taskpool';
-import common from '@ohos.app.ability.common'
+import common from '@ohos.app.ability.common';
 import { CacheStrategy } from './model/ImageKnifeData';
 import { PixelMapTransformation } from './transform/PixelMapTransformation';
+import { DownsampleStrategy } from './downsampling/DownsampleStartegy';
 
 export interface HeaderOptions {
   key: string;
   value: Object;
 }
+
 @Observed
 export class ImageKnifeOption {
   // 主图资源
@@ -29,38 +31,31 @@ export class ImageKnifeOption {
   placeholderSrc?: string | PixelMap | Resource;
   // 失败占位图
   errorholderSrc?: string | PixelMap | Resource;
-
   headerOption?: Array<HeaderOptions>;
-
   // 自定义缓存关键字
   signature?: string;
-
   // 主图填充效果
   objectFit?: ImageFit
-
   // 占位图填充效果
   placeholderObjectFit?: ImageFit
-
   // 错误图填充效果
   errorholderObjectFit?: ImageFit
-
   customGetImage?: (context: Context, src: string | PixelMap | Resource) => Promise<ArrayBuffer | undefined>
-
   border?: BorderOptions
   // 缓存策略
   writeCacheStrategy?: CacheStrategy
   // 仅使用缓存加载数据
   onlyRetrieveFromCache?: boolean = false;
-
+  priority?: taskpool.Priority = taskpool.Priority.LOW
-  priority? : taskpool.Priority = taskpool.Priority.LOW
-
   context?: common.UIAbilityContext;
 
   progressListener?: (progress: number)=>void;
 
   transformation?: PixelMapTransformation
   onLoadListener?: OnLoadCallBack | undefined;
-
+  // 下采样
+  downsampling?: DownsampleStrategy = DownsampleStrategy.NONE
+  autoResize?:boolean
   constructor() {
 
   }

library/src/main/ets/ImageKnifeRequest.ets

@@ -15,7 +15,7 @@
 import { ImageKnifeOption } from './ImageKnifeOption';
 import common from '@ohos.app.ability.common';
 import { ImageKnifeRequestSource } from './model/ImageKnifeData';
-
+import { DownsampleStrategy } from './downsampling/DownsampleStartegy';
 
 export class ImageKnifeRequest {
   requestState: ImageKnifeRequestState = ImageKnifeRequestState.PROGRESS
@@ -25,20 +25,29 @@ export class ImageKnifeRequest {
   context: common.UIAbilityContext
   ImageKnifeRequestCallback: ImageKnifeRequestCallback
   componentVersion: number = 0
-  headers: Map<string,Object> = new Map<string,Object>()
+  headers: Map<string, Object> = new Map<string, Object>()
+  downsampType?: DownsampleStrategy
+  autoResizes?:boolean
+
   constructor(option: ImageKnifeOption,
               uIAbilityContext: common.UIAbilityContext,
               width: number,
               height: number,
               version: number,
-              ImageKnifeRequestCallback: ImageKnifeRequestCallback) {
+              ImageKnifeRequestCallback: ImageKnifeRequestCallback,
+              downsampType?: DownsampleStrategy,
+              autoResizes?:boolean
+  ) {
     this.imageKnifeOption = option
     this.context = uIAbilityContext
     this.componentWidth = width
     this.componentHeight = height
     this.componentVersion = version
     this.ImageKnifeRequestCallback = ImageKnifeRequestCallback
+    this.downsampType = downsampType
+    this.autoResizes = autoResizes
   }
+
   // RequestOption调用header对于的方法
   addHeader(key: string, value: Object) {
     this.headers.set(key, value);
@@ -63,5 +72,5 @@ export enum ImageKnifeRequestState {
 
 
 export interface ImageKnifeRequestCallback {
-  showPixelMap: (version: number, pixelMap: PixelMap | string , requestSource: ImageKnifeRequestSource) => void;
+  showPixelMap: (version: number, pixelMap: PixelMap | string, requestSource: ImageKnifeRequestSource) => void;
 }

library/src/main/ets/components/ImageKnifeComponent.ets

@@ -18,6 +18,7 @@ import common from '@ohos.app.ability.common';
 import { ImageKnife } from '../ImageKnife';
 import { LogUtil } from '../utils/LogUtil';
 import { ImageKnifeRequestSource } from '../model/ImageKnifeData';
+import { Downsampler } from '../downsampling/Downsampler';
 
 @Component
 export struct ImageKnifeComponent {
@@ -33,6 +34,8 @@ export struct ImageKnifeComponent {
   private currentHeight: number = 0
   private componentVersion: number = 0
   private currentContext: common.UIAbilityContext | undefined = undefined
+  private targetHeight: number =0
+  private targetWidth: number =0
 
   aboutToAppear(): void {
     //闪动问题失效，注释相应代码后续修复
@@ -82,7 +85,10 @@ export struct ImageKnifeComponent {
             ImageKnife.getInstance().execute(this.getRequest(this.currentWidth, this.currentHeight))
           }
         }
-      })
+      }).sourceSize({
+          width:250,
+          height:250
+    })
   }
 
   watchImageKnifeOption() {
@@ -116,8 +122,9 @@ export struct ImageKnifeComponent {
             }
             this.pixelMap = pixelMap
             if (typeof this.pixelMap !== 'string') {
+              let info =await this.pixelMap.getImageInfo()
+              //图片自适应处理
               if (this.imageKnifeOption.objectFit === ImageFit.Auto) {
-                let info = await this.pixelMap.getImageInfo()
 
                 this.adaptiveWidth = this.currentWidth
                 this.adaptiveHeight = info.size.height * this.currentWidth / info.size.width

library/src/main/ets/downsampling/BaseDownsampling.ets

@@ -0,0 +1,26 @@
+/*
+ * Copyright (C) 2024 Huawei Device Co., Ltd.
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+import { lang } from '@kit.ArkTS';
+import { SampleSizeRounding } from './downsampleUtils';
+type ISendable = lang.ISendable;
+
+export interface BaseDownsampling extends ISendable {
+  getName(): string
+
+  getScaleFactor(sourceWidth: number, sourceHeight: number, requestWidth: number, requestHeight: number): number
+
+  getSampleSizeRounding(sourceWidth: number, sourceHeight: number, requestWidth: number, requestHeight: number): SampleSizeRounding
+}

library/src/main/ets/downsampling/DownsampleStartegy.ets

@@ -0,0 +1,237 @@
+/*
+ * Copyright (C) 2024 Huawei Device Co., Ltd.
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+import { BaseDownsampling } from './BaseDownsampling';
+import { highestOneBit,SampleSizeRounding } from './downsampleUtils';
+//FitCenter类实现DownsampleStartegy
+@Sendable
+export class FitCenter implements BaseDownsampling {
+  getName() {
+    return "FitCenter"
+  }
+
+  //实现 getScaleFactor 方法
+  getScaleFactor(sourceWidth: number, sourceHeight: number, requestedWidth: number, requestedHeight: number,autoResize?:boolean): number {
+    const IS_BITMAP_FACTORY_SCALING_SUPPORTED = autoResize; //这里需要根据实际情况设置这个值
+    if (IS_BITMAP_FACTORY_SCALING_SUPPORTED) {
+      const widthPercentage = requestedWidth / sourceWidth
+      const heightPercentage = requestedHeight / sourceHeight
+      return Math.min(widthPercentage, heightPercentage)
+    }else{
+      //类似 AT_LEAST,但只要求一个维度或另一个维度大于等于请求的尺寸
+      const maxIntegerFactor = Math.max(sourceHeight/requestedHeight, sourceWidth/requestedWidth);
+      const a = maxIntegerFactor === 0 ? 1 : 1 / highestOneBit(maxIntegerFactor)
+      return a;
+    }
+  }
+
+  //实现 getSampleSizeRounding 方法
+  getSampleSizeRounding(sourceWidth: number, sourceHeight: number, requestedWidth: number, requestedHeight: number,autoResize?:boolean): number {
+    const IS_BITMAP_FACTORY_SCALING_SUPPORTED = autoResize; //这里需要根据实际情况设置这个值
+
+    if (!IS_BITMAP_FACTORY_SCALING_SUPPORTED) {
+      return 0;
+    } else {
+      // TODO: 这个逻辑可能不正确，但是如果不这样做，我们可能会跳过一个采样尺寸，因为 QUALITY 更喜欢宽度和高度缩放因子中比较小的那个
+      //  MEMORY 折中方案,他让我们更喜欢两者中较大的那个
+        return SampleSizeRounding.MEMORY;
+    }
+
+  }
+}
+
+//None 类实现 DownsampleStrategy 接口
+@Sendable
+export class None implements BaseDownsampling{
+  getName(): string{
+    return "DownsampleNone"
+  }
+
+  //实现 getScaleFactor 方法
+  public getScaleFactor(sourceWidth: number, sourceHeight: number, requestedWidth: number, requestedHeight: number): number {
+    //不进行任何下采样，缩放因子为 1
+    return 1;
+  }
+
+  //实现 getSampleSizeRounding 方法
+  public getSampleSizeRounding(sourceWidth: number, sourceHeight: number, requestedWidth: number, requestedHeight: number): SampleSizeRounding {
+    //总是返回 QUALITY
+    return SampleSizeRounding.QUALITY
+
+  }
+}
+
+
+/*宽高进行等比缩放宽高里面最小的比例先放进去
+然后再更据原图的缩放比去适配另一边*/
+@Sendable
+export class CenterOutside implements BaseDownsampling {
+  getName() {
+    return "CenterOutside"
+  }
+
+  //实现 getScaleFactor 方法
+  getScaleFactor(sourceWidth: number, sourceHeight: number, requestedWidth: number, requestedHeight: number): number {
+    const widthPercentage = requestedWidth / sourceWidth;
+    const heightPercentage = requestedHeight / sourceHeight;
+    //返回宽度和高度比例中最大的值
+    return Math.max(widthPercentage, heightPercentage);
+  }
+
+  //实现 getSampleSizeRounding 方法
+  getSampleSizeRounding(sourceWidth: number, sourceHeight: number, requestedWidth: number, requestedHeight: number): SampleSizeRounding {
+    //根据 CenterOutside 的逻辑，总是返回 QUALITY
+    return SampleSizeRounding.QUALITY;
+  }
+}
+
+/*请求尺寸大于实际尺寸不进行放大,按照原图展示*/
+@Sendable
+export class Atleast implements BaseDownsampling {
+  //构造函数
+  constructor(){
+    //TypeScript 默认构造函数不需要特殊标记
+  }
+
+  getName() {
+    return "AtLeast"
+  }
+
+  //实现 getScaleFactor 方法
+  public getScaleFactor(sourceWidth: number, sourceHeight: number, requestedWidth: number, requestedHeight: number): SampleSizeRounding {
+    //计算最小整数因子
+    const minIntegerFactor = Math.min(sourceHeight / requestedHeight, sourceWidth / requestedWidth)
+    //根据最小整数因子计算缩放因子
+    return minIntegerFactor === 0 ? 1 : 1 / highestOneBit(minIntegerFactor);
+  }
+  //实现 getSampleSizeRounding 方法
+  public getSampleSizeRounding(sourceWidth: number, sourceHeight: number, requestedWidth: number, requestedHeight: number): SampleSizeRounding {
+    //总是返回 QUALITY
+    return SampleSizeRounding.QUALITY
+  }
+}
+
+/*请求尺寸大于实际尺寸不进行放大,按照原图展示*/
+@Sendable
+export class AtMost implements BaseDownsampling {
+  getName() {
+    return "AtMost"
+  }
+
+  //实现 getScaleFactor 方法
+  getScaleFactor(sourceWidth: number, sourceHeight: number, requestedWidth: number, requestedHeight: number): number {
+    const maxIntegerFactor = Math.ceil(Math.max(sourceHeight / requestedHeight, sourceWidth / requestedWidth));
+    let lesserOrEqualSampleSize = Math.max(1, highestOneBit(maxIntegerFactor));
+    let greaterOrEqualSampleSize = lesserOrEqualSampleSize
+    // if (lesserOrEqualSampleSize < maxIntegerFactor) {
+    //   let greaterOrEqualSampleSize = lesserOrEqualSampleSize <<= 1; // lest shift by 1
+    // }
+    greaterOrEqualSampleSize = lesserOrEqualSampleSize << (lesserOrEqualSampleSize < maxIntegerFactor ? 1 : 0)
+    //返回缩放因子
+    return 1 / greaterOrEqualSampleSize
+  }
+
+  highestOneBit(i: number): number {
+    i |= (i >> 1);
+    i |= (i >> 2);
+    i |= (i >> 4);
+    i |= (i >> 8);
+    i |= (i >> 16);
+    return i - (i >>> 1);
+  }
+
+  //实现 getSampleSizeRounding 方法
+  getSampleSizeRounding(sourceWidth: number, sourceHeight: number, requestedWidth: number, requestHeight: number): SampleSizeRounding {
+    //根据 AtMost 的逻辑，总是返回 MEMORY
+    return SampleSizeRounding.MEMORY
+  }
+}
+
+/*宽高进行等比缩放宽高里面最大的比例先放进去
+然后再更据原图的缩放比去适配另一边*/
+@Sendable
+export class CenterInside implements BaseDownsampling {
+  getName() {
+    return "CenterInside"
+  }
+
+  //实现 getScaleFactor 方法
+  getScaleFactor(sourceWidth: number, sourceHeight: number, requestedWidth: number, requestedHeight: number,autoResize?:boolean): number {
+    //获取 FIT_CENTER 的缩放因子
+    const fitCenterScaleFactor : ESObject = this.getScale(sourceWidth,sourceHeight,requestedWidth,requestedHeight,autoResize);
+    //实现 getScaleFactor 方法
+    //返回不超过 1 的缩放因子，即尽量缩小图像以适应目标尺寸，但不会放大
+    return Math.min(1,fitCenterScaleFactor);
+
+  }
+
+  getScale(sourceWidth: number, sourceHeight: number, requestedWidth: number, requestedHeight: number,autoResize?:boolean): number {
+    const IS_BITMAP_FACTORY_SCALING_SUPPORTED = autoResize; //这里需要根据实际情况设置这个值
+    if (IS_BITMAP_FACTORY_SCALING_SUPPORTED) {
+      const widthPercentage = requestedWidth / sourceWidth
+      const heightPercentage = requestedHeight / sourceHeight
+      return Math.min(widthPercentage, heightPercentage)
+    }else{
+      //类似 AT_LEAST,但只要求一个维度或另一个维度大于等于请求的尺寸
+      const maxIntegerFactor = Math.max(sourceHeight/requestedHeight, sourceWidth/requestedWidth);
+
+      return maxIntegerFactor === 0 ? 1 : 1 / highestOneBit(maxIntegerFactor);
+
+  }
+}
+
+
+  //实现 getSampleSizeRounding 方法
+  getSampleSizeRounding(sourceWidth: number, sourceHeight: number, requestedWidth: number, requestedHeight: number,autoResize?:boolean): SampleSizeRounding {
+  //如果缩放因子为 1，表示没有缩放，优先选择质量
+    if (this.getScaleFactor(sourceWidth,sourceHeight,requestedWidth,requestedHeight,autoResize) === 1) {
+      return SampleSizeRounding.QUALITY
+    }
+    //否则，使用 FIL_CENTER 的 SampleSizeRounding 值
+    return this.getSampleSize(sourceWidth,sourceHeight,requestedWidth,requestedHeight);
+    }
+
+  highestOneBit(i: number): number {
+    i |= (i >> 1);
+    i |= (i >> 2);
+    i |= (i >> 4);
+    i |= (i >> 8);
+    i |= (i >> 16);
+    return i - (i >>> 1);
+  }
+
+  //实现 getSampleSizeRounding 方法
+  getSampleSize(sourceWidth: number, sourceHeight: number, requestedWidth: number, requestedHeight: number,autoResize?:boolean): SampleSizeRounding {
+    const IS_BITMAP_FACTORY_SCALING_SUPPORTED = autoResize; //这里需要根据实际情况设置这个值
+
+    if (IS_BITMAP_FACTORY_SCALING_SUPPORTED) {
+      return 0;
+    } else {
+      //   TODO: 这个逻辑可能不正确，但是如果不这样做，我们可能会跳过一个采样尺寸，因为 QUALITY 更喜欢宽度和高度缩放因子中比较小的那个
+      //    MEMORY 折中方案,他让我们更喜欢两者中较大的那个
+      //
+      // }
+      return SampleSizeRounding.MEMORY;
+    }
+  }
+}
+
+export enum DownsampleStrategy{
+  AT_LEAST,
+  AT_MOST,
+  FIT_CENTER,
+  CENTER_INSIDE,
+  CENTER_OUTSIDE,
+  NONE,
+}

library/src/main/ets/downsampling/Downsampler.ets

@@ -0,0 +1,175 @@
+/*
+ * Copyright (C) 2024 Huawei Device Co., Ltd.
+ * Licensed under the Apache License, Version 2.0 (the 'License');
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an 'AS IS' BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+import {
+  Atleast,
+  AtMost,
+  CenterInside,
+  CenterOutside,
+  DownsampleStrategy,
+  FitCenter,
+  None,
+} from './DownsampleStartegy';
+import { highestOneBit, SampleSizeRounding } from './downsampleUtils';
+
+export interface calculateScaleType {
+  targetWidth: number,
+  targetHeight: number
+}
+
+export class Downsampler {
+  calculateScaling(
+    typeValue: string | null,
+    sourceHeight: number, //原始宽高
+    sourceWidth: number | undefined,
+    //原始宽高	7106
+    requestHeight: number, //请求宽高
+    requestWidth: number, //请求宽高
+    downsampType: DownsampleStrategy | undefined,
+    autoResize:boolean |undefined
+
+  ): calculateScaleType {
+    let degreesToRotate: ESObject = 0; //获取旋转角度
+    const fileType = typeValue //获取图片类型
+    let powerOfTwoWidth: number | null = null;
+    let powerOfTwoHeight: number | null = null;
+    let targetWidth: number = 0
+    let targetHeight: number = 0
+    if (sourceHeight <= 0 || sourceWidth == undefined || sourceWidth == null || sourceWidth <= 0) {
+      throw new Error("Cannot found width or height");
+    }
+    let orientedSourceWidth = sourceWidth;
+    let orientedSourceHeight = sourceHeight;
+    if (this.isRotationRequired(degreesToRotate)) {
+      orientedSourceWidth = sourceHeight;
+      orientedSourceHeight = sourceWidth;
+    }
+    if (requestWidth && !requestHeight) {
+      targetWidth = this.round((requestHeight) * orientedSourceWidth / orientedSourceHeight)
+    } else if (requestHeight && !requestWidth) {
+      targetHeight = this.round((requestWidth) * orientedSourceHeight / orientedSourceWidth)
+    } else if (requestHeight && requestWidth) {
+      targetWidth = requestHeight == sourceWidth ? (this.isRotationRequired(degreesToRotate) ? sourceHeight : sourceWidth) : requestWidth;
+      targetHeight = requestHeight == sourceHeight ? (this.isRotationRequired(degreesToRotate) ? sourceWidth : sourceHeight) : requestWidth;
+    } else {
+      throw new Error("Cannot found width or height");
+    }
+    /*安卓的模式*/
+    let exactScaleFactor: number = new FitCenter()
+      .getScaleFactor(orientedSourceWidth, orientedSourceHeight, targetWidth, targetHeight,autoResize)
+    /*安卓的模式*/
+    let rounding: SampleSizeRounding = new FitCenter()
+      .getSampleSizeRounding(orientedSourceWidth, orientedSourceHeight, targetWidth, targetHeight,autoResize)
+    switch (downsampType) {
+      case DownsampleStrategy.FIT_CENTER:
+        exactScaleFactor = new FitCenter()
+          .getScaleFactor(orientedSourceWidth, orientedSourceHeight, targetWidth, targetHeight)
+        rounding = new FitCenter()
+          .getSampleSizeRounding(orientedSourceWidth, orientedSourceHeight, targetWidth, targetHeight)
+        break;
+      case DownsampleStrategy.NONE:
+        exactScaleFactor = new None()
+          .getScaleFactor(orientedSourceWidth, orientedSourceHeight, targetWidth, targetHeight)
+        rounding = new None()
+          .getSampleSizeRounding(orientedSourceWidth, orientedSourceHeight, targetWidth, targetHeight)
+        break
+      case DownsampleStrategy.AT_MOST:
+        exactScaleFactor = new AtMost()
+          .getScaleFactor(orientedSourceWidth, orientedSourceHeight, targetWidth, targetHeight)
+        rounding = new AtMost()
+          .getSampleSizeRounding(orientedSourceWidth, orientedSourceHeight, targetWidth, targetHeight)
+        break
+      case DownsampleStrategy.CENTER_INSIDE:
+        exactScaleFactor = new CenterInside()
+          .getScaleFactor(orientedSourceWidth, orientedSourceHeight, targetWidth, targetHeight,autoResize)
+        rounding = new CenterInside()
+          .getSampleSizeRounding(orientedSourceWidth, orientedSourceHeight, targetWidth, targetHeight,autoResize)
+        break
+      case DownsampleStrategy.AT_LEAST:
+        exactScaleFactor = new Atleast()
+          .getScaleFactor(orientedSourceWidth, orientedSourceHeight, targetWidth, targetHeight)
+        rounding = new Atleast()
+          .getSampleSizeRounding(orientedSourceWidth, orientedSourceHeight, targetWidth, targetHeight)
+        break
+      case DownsampleStrategy.CENTER_OUTSIDE:
+        exactScaleFactor = new CenterOutside()
+          .getScaleFactor(orientedSourceWidth, orientedSourceHeight, targetWidth, targetHeight)
+        rounding = new CenterOutside()
+          .getSampleSizeRounding(orientedSourceWidth, orientedSourceHeight, targetWidth, targetHeight)
+        break
+    }
+    if (exactScaleFactor <= 0) {
+      throw new Error("Cannot round with exactScaleFactor");
+    }
+    if (rounding == null) {
+      throw new Error("Cannot round with null rounding");
+    }
+    let outWidth: number = this.round(exactScaleFactor * orientedSourceWidth);
+    let outHeight: number = this.round(exactScaleFactor * orientedSourceHeight);
+    let widthScaleFactor = orientedSourceWidth / outWidth;
+    let heightScaleFactor = orientedSourceHeight / outHeight;
+    let scaleFactor = rounding == 1 ? Math.max(widthScaleFactor, heightScaleFactor) : Math.min(widthScaleFactor, heightScaleFactor) //将整型的缩放因子转换为2的次幂采样大小
+    let powerOfTwoSampleSize: number = scaleFactor;
+    powerOfTwoSampleSize = Math.max(1, highestOneBit(scaleFactor))
+    if (rounding == 1 && (powerOfTwoSampleSize < (1 / exactScaleFactor))) {
+      powerOfTwoSampleSize = powerOfTwoSampleSize << 1;
+    }
+    //基于上一步得出的采样大小，根据不同的图片类型，计算采样后的图片尺寸
+    if (fileType === "jpeg") {
+      let nativeScaling = Math.min(powerOfTwoSampleSize, 8);
+      powerOfTwoWidth = Math.ceil(orientedSourceWidth / nativeScaling);
+      powerOfTwoHeight = Math.ceil(orientedSourceHeight / nativeScaling);
+      let secondaryScaling = Math.floor(powerOfTwoSampleSize / 8);
+      if (secondaryScaling > 0) {
+        powerOfTwoWidth = powerOfTwoWidth / secondaryScaling;
+        powerOfTwoHeight = powerOfTwoHeight / secondaryScaling;
+      }
+    } else if (fileType === "png") {
+      powerOfTwoWidth = Math.floor(orientedSourceWidth / powerOfTwoSampleSize);
+      powerOfTwoHeight = Math.floor(orientedSourceHeight / powerOfTwoSampleSize);
+    } else if (fileType === "webp") {
+      powerOfTwoWidth = Math.round(orientedSourceWidth / powerOfTwoSampleSize);
+      powerOfTwoHeight = Math.round(orientedSourceHeight / powerOfTwoSampleSize);
+    } else {
+      powerOfTwoWidth = orientedSourceWidth / powerOfTwoSampleSize;
+      powerOfTwoHeight = orientedSourceHeight / powerOfTwoSampleSize;
+    }
+    console.log(`输出长宽 === 高:${powerOfTwoHeight}宽:${powerOfTwoWidth}`,);
+    let a: calculateScaleType = {
+      "targetWidth": powerOfTwoWidth,
+      "targetHeight": powerOfTwoHeight
+    }
+    return a
+  }
+
+  round(value: number): number {
+    return Math.floor(value + 0.5);
+  }
+
+  isRotationRequired(degreesToRotate: number): boolean {
+    return degreesToRotate == 90 || degreesToRotate == 270;
+  }
+
+  getDensityMultiplier(adjustedScaleFactor: number): number {
+    return Math.round(Number.MAX_VALUE * (adjustedScaleFactor <= 1 ? adjustedScaleFactor : 1 / adjustedScaleFactor));
+  }
+
+  adjustTargetDensityForError(adjustedScaleFactor: number): number {
+    let densityMultiplier = this.getDensityMultiplier(adjustedScaleFactor);
+    let targetDensity = this.round(densityMultiplier * adjustedScaleFactor);
+    let scaleFactorWithError = targetDensity / densityMultiplier;
+    let difference = adjustedScaleFactor / scaleFactorWithError;
+    return this.round(difference * targetDensity)
+  }
+}

library/src/main/ets/downsampling/downsampleUtils.ets

@@ -0,0 +1,27 @@
+/*
+ * Copyright (C) 2024 Huawei Device Co., Ltd.
+ * Licensed under the Apache License, Version 2.0 (the 'License');
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an 'AS IS' BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+export enum SampleSizeRounding {
+  QUALITY,
+  MEMORY
+}
+
+export function highestOneBit(i: number): number {
+  i |= (i >> 1);
+  i |= (i >> 2);
+  i |= (i >> 4);
+  i |= (i >> 8);
+  i |= (i >> 16);
+  return i - (i >>> 1);
+}

library/src/main/ets/model/ImageKnifeData.ets

@@ -17,6 +17,7 @@ import { ImageKnifeRequest } from '../ImageKnifeRequest'
 import { IEngineKey } from '../key/IEngineKey'
 import { PixelMapTransformation } from '../transform/PixelMapTransformation'
 import common from '@ohos.app.ability.common';
+import { DownsampleStrategy} from '../downsampling/DownsampleStartegy'
 
 export interface ImageKnifeData {
   source: PixelMap | string,
@@ -60,7 +61,10 @@ export interface RequestJobResult {
   fileKey: string
   loadFail?: string,
 }
-
+export interface targetCcaleType {
+  width: number,
+  height: number
+}
 /**
  * request子线程处理时的请求参数
  */
@@ -76,5 +80,9 @@ export interface RequestJobRequest {
   writeCacheStrategy?: CacheStrategy
   signature?: string
   engineKey: IEngineKey
+  targetWidth:number
+  targetHeight: number
+  downsampType?:DownsampleStrategy
+  autoResize?:boolean
 }