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

@@ -126,8 +126,6 @@ struct DownSamplePage {
       desiredPixelFormat: 3,
     }
     let imageInfo = await imageSource.getImageInfo()
-
-    if (this.imageKnifeOption.downsampleOf !== DownsampleStrategy.NONE){
     let reqSize =
       new Downsampler().calculateScaling(typeValue, imageInfo.size.width, imageInfo.size.height, 300,
         300, this.imageKnifeOption.downsampleOf)
@@ -138,8 +136,6 @@ struct DownSamplePage {
         height: reqSize.height
       }
     }
-    }
-
     // 创建pixelMap
     imageSource.createPixelMap(decodingOptions).then((pixelMap: image.PixelMap) => {
       this.afterSampling = pixelMap.getPixelBytesNumber()

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

@@ -40,9 +40,19 @@ struct Index {
             uri: 'pages/TestCommonImage',
           });
         })
-        Button(this.getResourceString($r('app.string.Multiple_images')) + " + reuse + LazyForeach").margin({top:10}).onClick(()=>{
+        Button($r('app.string.Image_Downsampling_Functionality')).margin({top:10}).onClick(()=>{
           router.push({
-            uri: 'pages/UserPage',
+            uri: 'pages/DownSamplePage',
+          });
+        })
+        Button($r('app.string.Test_Task_error')).margin({top:10}).onClick(()=>{
+          router.push({
+            uri: 'pages/TestTaskResourcePage',
+          });
+        })
+        Button($r('app.string.Test_HSP')).margin({top:10}).onClick(()=>{
+          router.push({
+            uri: 'pages/TestHspPreLoadImage',
 
           });
         })
@@ -52,9 +62,22 @@ struct Index {
 
           });
         })
-        Button($r('app.string.Image_Downsampling_Functionality')).margin({top:10}).onClick(()=>{
+        Button($r('app.string.Test_custom_download')).margin({top:10}).onClick(()=>{
           router.push({
-            uri: 'pages/DownSamplePage',
+            uri: 'pages/TestSetCustomImagePage',
+
+          });
+        })
+        Button(this.getResourceString($r('app.string.Multiple_images')) + " + LazyForEach").margin({top:10}).onClick(()=>{
+          router.push({
+            uri: 'pages/ManyPhotoShowPage',
+
+          });
+        })
+        Button(this.getResourceString($r('app.string.Multiple_images')) + " + reuse + LazyForeach").margin({top:10}).onClick(()=>{
+          router.push({
+            uri: 'pages/UserPage',
+
           });
         })
         Button($r('app.string.Display_long_image')).margin({top:10}).onClick(()=>{
@@ -63,25 +86,17 @@ struct Index {
 
           });
         })
-        Button($r('app.string.Image_Transformation')).margin({top:10}).onClick(()=>{
+        Button($r('app.string.Image_scaling')).margin({top:10}).onClick(()=>{
           router.push({
-            uri: 'pages/ImageTransformation',
-
-          });
-
-        })
-        Button($r('app.string.Test_media_URL')).margin({top:10}).onClick(()=>{
-          router.push({
-            uri: 'pages/dataShareUriLoadPage',
+            uri: 'pages/TransformPage',
 
           });
         })
-        Button($r('app.string.Different_ObjectFit')).margin({top:10}).onClick(()=>{
+        Button(this.getResourceString($r('app.string.Message_list')) + " + List").margin({top:10}).onClick(()=>{
           router.push({
-            uri: 'pages/ObjectFitPage',
+            uri: 'pages/TestImageFlash',
 
           });
-
         })
         Button($r('app.string.Custom_cache_key')).margin({top:10}).onClick(()=>{
           router.push({
@@ -89,39 +104,6 @@ struct Index {
 
           });
         })
-        Button($r('app.string.Test_image_loading_success_or_failure_events')).margin({top:10}).onClick(()=>{
-          router.push({
-            uri: 'pages/LoadStatePage',
-          })
-        })
-        Button($r('app.string.Image_scaling')).margin({top:10}).onClick(()=>{
-          router.push({
-            uri: 'pages/TransformPage',
-
-          });
-        })
-
-        Button($r('app.string.Test_HSP')).margin({top:10}).onClick(()=>{
-          router.push({
-            uri: 'pages/TestHspPreLoadImage',
-
-          });
-        })
-
-        Button($r('app.string.Test_custom_download')).margin({top:10}).onClick(()=>{
-          router.push({
-            uri: 'pages/TestSetCustomImagePage',
-
-          });
-        })
-
-        Button(this.getResourceString($r('app.string.Message_list')) + " + List").margin({top:10}).onClick(()=>{
-          router.push({
-            uri: 'pages/TestImageFlash',
-
-          });
-        })
-
         Button($r('app.string.Preloading_images_to_cache')).margin({top:10}).onClick(()=>{
           router.push({
             uri: 'pages/TestPrefetchToFileCache',
@@ -146,7 +128,27 @@ struct Index {
 
           });
         })
+        Button($r('app.string.Image_Transformation')).margin({top:10}).onClick(()=>{
+          router.push({
+            uri: 'pages/ImageTransformation',
 
+          });
+
+        })
+
+        Button($r('app.string.Different_ObjectFit')).margin({top:10}).onClick(()=>{
+          router.push({
+            uri: 'pages/ObjectFitPage',
+
+          });
+
+        })
+
+        Button($r('app.string.Test_image_loading_success_or_failure_events')).margin({top:10}).onClick(()=>{
+          router.push({
+            uri: 'pages/LoadStatePage',
+          })
+        })
 
         Button($r('app.string.Test_removing_image_cache_interface')).margin({top:10}).onClick(()=>{
           router.push({
@@ -159,11 +161,13 @@ struct Index {
 
           });
         })
-        Button($r('app.string.Test_Task_error')).margin({top:10}).onClick(()=>{
+        Button($r('app.string.Test_media_URL')).margin({top:10}).onClick(()=>{
           router.push({
-            uri: 'pages/TestTaskResourcePage',
+            uri: 'pages/dataShareUriLoadPage',
+
           });
         })
+
       }
     } .width('100%')
     .height('100%')

library/src/main/ets/ImageKnifeLoader.ets

@@ -389,27 +389,27 @@ export class ImageKnifeLoader {
   }
 
   static downsamplerReqSize(typeValue: string, request: RequestJobRequest, size: Size,
-    SRC?: ImageKnifeRequestSource):image.DecodingOptions {
+    SRC?: ImageKnifeRequestSource) {
     let reqSize =
       new Downsampler().calculateScaling(typeValue, size.width, size.height, request.targetWidth, request.targetHeight,
         request.downsampType)
     if (typeValue == "svg") {
-      return {
+      return ({
         editable: true,
-        desiredSize: {
+        desiredSize: ({
           height: vp2px(reqSize.height),
           width: vp2px(reqSize.width)
-        }
+        } as Size)
 
-      }
+      } as image.DecodingOptions)
     } else {
-      return {
+      return ({
         editable: request.requestSource === SRC && request.transformation !== undefined ? true : false,
-        desiredSize:{
+        desiredSize: ({
           width: reqSize.width,
           height: reqSize.height
-        }
-      }
+        } as Size)
+      } as image.DecodingOptions)
     }
   }
 }

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

@@ -20,4 +20,7 @@ export interface BaseDownsampling {
   getName(): string
 
   getScaleFactor(sourceWidth: number, sourceHeight: number, requestWidth: number, requestHeight: number,downsampType?:DownsampleStrategy): number
+  //
+  getSampleSizeType(sourceWidth: number, sourceHeight: number, requestWidth: number,
+    requestHeight: number,downsampType?:DownsampleStrategy): SampleSizeRounding
 }

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

@@ -28,16 +28,50 @@ export class FitCenter implements BaseDownsampling {
       width: round(getScale(sourceWidth, sourceHeight, requestedWidth, requestedHeight, downsampType) * sourceWidth),
       height:round(getScale(sourceWidth, sourceHeight, requestedWidth, requestedHeight, downsampType) * sourceHeight)
     }
-    let scaleFactor = downsampType === DownsampleStrategy.FIT_CENTER_QUALITY?
-    Math.max(1, highestOneBit(Math.max(sourceWidth / outSize.width, sourceHeight / outSize.height))) :
+    let scaleFactor = this.getSampleSizeType(sourceWidth, sourceHeight, requestedWidth, requestedHeight, downsampType)===
+    SampleSizeRounding.QUALITY? Math.max(1, highestOneBit(Math.max(sourceWidth / outSize.width, sourceHeight / outSize.height))) :
     Math.max(1, highestOneBit(Math.min(sourceWidth / outSize.width, sourceHeight / outSize.height)))//将整型的缩放因子转换为2的次幂采样大小
 
-    if (downsampType === DownsampleStrategy.FIT_CENTER_MEMORY
-      && (scaleFactor < (1 / getScale(sourceWidth, sourceHeight, requestedWidth, requestedHeight, downsampType)))) {
+    if (this.getSampleSizeType(sourceWidth, sourceHeight, requestedWidth, requestedHeight, downsampType)===
+    SampleSizeRounding.MEMORY && (scaleFactor < (1 / getScale(sourceWidth, sourceHeight, requestedWidth, requestedHeight, downsampType)))) {
       scaleFactor = scaleFactor << 1;
     }
     return scaleFactor
   }
+
+  getSampleSizeType(sourceWidth: number, sourceHeight: number, requestedWidth: number, requestedHeight: number,
+    downsampType: DownsampleStrategy
+  ): number {
+    if (downsampType === DownsampleStrategy.FIT_CENTER_QUALITY) {
+      return SampleSizeRounding.QUALITY;
+    } else {
+      return SampleSizeRounding.MEMORY;
+    }
+
+  }
+}
+
+export class None implements BaseDownsampling {
+  getName(): string {
+    return "DownsampleNone"
+  }
+
+  public getScaleFactor(sourceWidth: number, sourceHeight: number, requestedWidth: number,
+    requestedHeight: number): number {
+    let outSize: Size = {
+      width: round(sourceWidth),
+      height:round(sourceHeight)
+    }
+    let scaleFactor =
+      Math.max(1, highestOneBit(Math.max(sourceWidth / outSize.width, sourceHeight / outSize.height)))
+    return scaleFactor
+  }
+
+  //实现 getSampleSizeType 方法
+  public getSampleSizeType(sourceWidth: number, sourceHeight: number, requestedWidth: number,
+    requestedHeight: number): SampleSizeRounding {
+    return SampleSizeRounding.QUALITY
+  }
 }
 
 
@@ -61,6 +95,11 @@ export class CenterOutside implements BaseDownsampling {
 
     return scaleFactor
   }
+
+  getSampleSizeType(sourceWidth: number, sourceHeight: number, requestedWidth: number,
+    requestedHeight: number): SampleSizeRounding {
+    return SampleSizeRounding.QUALITY;
+  }
 }
 
 /*请求尺寸大于实际尺寸不进行放大,按照原图展示*/
@@ -79,7 +118,7 @@ export class AtMost implements BaseDownsampling {
       greaterOrEqualSampleSize = lesserOrEqualSampleSize <<= 1;
     }
     greaterOrEqualSampleSize = lesserOrEqualSampleSize << (lesserOrEqualSampleSize < maxIntegerFactor ? 1 : 0)
-
+    //返回缩放因子
     let outSize: Size = {
       width: round((1 / greaterOrEqualSampleSize) * sourceWidth),
       height:round((1 / greaterOrEqualSampleSize) * sourceHeight)
@@ -90,6 +129,13 @@ export class AtMost implements BaseDownsampling {
     }
     return scaleFactor
   }
+
+
+  getSampleSizeType(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
@@ -101,6 +147,7 @@ export class CenterInside implements BaseDownsampling {
   getScaleFactor(sourceWidth: number, sourceHeight: number, requestedWidth: number, requestedHeight: number,
     downsampType: DownsampleStrategy
   ): number {
+
     let outSize: Size = {
       width: round(Math.min(1, getScale(sourceWidth, sourceHeight, requestedWidth, requestedHeight, downsampType)) * sourceWidth),
       height:round(Math.min(1, getScale(sourceWidth, sourceHeight, requestedWidth, requestedHeight, downsampType)) * sourceHeight)
@@ -126,7 +173,17 @@ export class CenterInside implements BaseDownsampling {
       return SampleSizeRounding.QUALITY
     }
     //否则，使用 FIL_CENTER 的 SampleSizeRounding 值
-    return downsampType === DownsampleStrategy.CENTER_INSIDE_MEMORY?SampleSizeRounding.MEMORY:SampleSizeRounding.QUALITY
+    return this.getSampleSize(sourceWidth, sourceHeight, requestedWidth, requestedHeight, downsampType);
+  }
+
+  getSampleSize(sourceWidth: number, sourceHeight: number, requestedWidth: number, requestedHeight: number,
+    downsampType: DownsampleStrategy
+  ): SampleSizeRounding {
+    if (downsampType === DownsampleStrategy.CENTER_INSIDE_MEMORY) {
+      return SampleSizeRounding.MEMORY;
+    } else {
+      return SampleSizeRounding.QUALITY;
+    }
   }
 }
 

library/src/main/ets/downsampling/DownsampleUtils.ets

@@ -28,7 +28,7 @@ export enum SampleSizeRounding {
   //（质量优先）
   QUALITY
 }
-//找出给定整数 i 中最高位的1（即最左边的1）所代表的值
+
 export function highestOneBit(i: number): number {
   i |= (i >> 1);
   i |= (i >> 2);
@@ -52,7 +52,6 @@ export function getScale(sourceWidth: number, sourceHeight: number, requestedWid
 
   }
 }
-//四舍五入
 export function  round(value: number): number {
   return Math.floor(value + 0.5);
 }

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

@@ -18,7 +18,11 @@ import {
   CenterOutside,
   DownsampleStrategy,
   FitCenter,
+  None,
 } from './DownsampleStartegy';
+import { highestOneBit, round, SampleSizeRounding } from './DownsampleUtils';
+
+
 export class Downsampler {
   calculateScaling(
     typeValue: string,
@@ -35,6 +39,22 @@ export class Downsampler {
     let downsampler = this.getDownsampler(downsampType);
     let scaleFactor: number =
       downsampler.getScaleFactor(sourceWidth, sourceHeight, requestWidth, requestHeight, downsampType);//缩放比
+    // let rounding: SampleSizeRounding =
+    //   downsampler.getSampleSizeType(sourceWidth, sourceHeight, requestWidth, requestHeight, downsampType); //采样类型
+    //根据缩放比重新计算宽高
+    // let outSize: Size = {
+    //   width: round(exactScaleFactor * sourceWidth),
+    //   height:round(exactScaleFactor * sourceHeight)
+    // }
+    // let scaleFactor =
+    //   rounding == SampleSizeRounding.QUALITY ? Math.max(sourceWidth / exactScaleFactor.width, sourceHeight / exactScaleFactor.height) :
+    //   Math.min(sourceWidth / exactScaleFactor.width, sourceHeight / exactScaleFactor.height) //重新计算宽高比
+
+    // scaleFactor = Math.max(1, highestOneBit(scaleFactor))//将整型的缩放因子转换为2的次幂采样大小
+    //
+    // if (rounding == 0 && (scaleFactor < (1 / exactScaleFactor))) {
+    //   scaleFactor = scaleFactor << 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 (typeValue === "png") {
       return {
@@ -54,11 +74,14 @@ export class Downsampler {
       }
     }
   }
+
   getDownsampler(downsampType: DownsampleStrategy) {
     switch (downsampType) {
       case DownsampleStrategy.FIT_CENTER_MEMORY:
       case DownsampleStrategy.FIT_CENTER_QUALITY:
         return new FitCenter();
+      case DownsampleStrategy.NONE:
+        return new None();
       case DownsampleStrategy.AT_MOST:
         return new AtMost();
       case DownsampleStrategy.CENTER_INSIDE_MEMORY: