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/*
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* Copyright (C) 2024 Huawei Device Co., Ltd.
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* Licensed under the Apache License, Version 2.0 (the 'License');
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* you may not use this file except in compliance with the License.
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* You may obtain a copy of the License at
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*
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* http://www.apache.org/licenses/LICENSE-2.0
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*
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* Unless required by applicable law or agreed to in writing, software
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* distributed under the License is distributed on an 'AS IS' BASIS,
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* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
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* See the License for the specific language governing permissions and
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* limitations under the License.
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*/
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import { DownsampleStrategy, ImageKnifeComponent } from '@ohos/imageknife';
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@Entry
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@Component
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struct DownSamplePage {
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@State message: string = 'Hello World';
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build() {
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Scroll() {
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Column(){
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ImageKnifeComponent({
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imageKnifeOption: {
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loadSrc: $r("app.media.jpgSample"),
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placeholderSrc: $r("app.media.loading"),
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errorholderSrc: $r("app.media.app_icon"),
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downsampling: DownsampleStrategy.FIT_CENTER,
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objectFit: ImageFit.Contain,
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autoResize:true
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}
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})
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.height(300)
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.width(300)
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.borderWidth(1)
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.borderColor(Color.Pink)
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ImageKnifeComponent({
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imageKnifeOption: {
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loadSrc: "http://g.hiphotos.baidu.com/image/pic/item/6d81800a19d8bc3e770bd00d868ba61ea9d345f2.jpg",
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placeholderSrc: $r("app.media.loading"),
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errorholderSrc: $r("app.media.app_icon"),
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downsampling: DownsampleStrategy.AT_MOST,
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objectFit: ImageFit.Contain,
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autoResize:true
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}
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})
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.height(300)
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.width(300)
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.borderWidth(1)
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.borderColor(Color.Pink)
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ImageKnifeComponent({
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imageKnifeOption: {
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loadSrc: $r("app.media.jpgSample"),
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placeholderSrc: $r("app.media.loading"),
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errorholderSrc: $r("app.media.app_icon"),
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downsampling: DownsampleStrategy.AT_LEAST,
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objectFit: ImageFit.Contain,
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autoResize:true
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}
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})
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.height(300)
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.width(300)
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.borderWidth(1)
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.borderColor(Color.Pink)
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ImageKnifeComponent({
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imageKnifeOption: {
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loadSrc: $r("app.media.jpgSample"),
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placeholderSrc: $r("app.media.loading"),
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errorholderSrc: $r("app.media.app_icon"),
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downsampling: DownsampleStrategy.CENTER_INSIDE,
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objectFit: ImageFit.Contain,
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autoResize:true
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}
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})
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.height(300)
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.width(300)
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.borderWidth(1)
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.borderColor(Color.Pink)
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ImageKnifeComponent({
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imageKnifeOption: {
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loadSrc: $r("app.media.jpgSample"),
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placeholderSrc: $r("app.media.loading"),
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errorholderSrc: $r("app.media.app_icon"),
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downsampling: DownsampleStrategy.CENTER_OUTSIDE,
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objectFit: ImageFit.Contain,
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autoResize:true
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}
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})
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.height(300)
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.width(300)
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.borderWidth(1)
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.borderColor(Color.Pink)
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ImageKnifeComponent({
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imageKnifeOption: {
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loadSrc: $r("app.media.jpgSample"),
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placeholderSrc: $r("app.media.loading"),
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errorholderSrc: $r("app.media.app_icon"),
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downsampling: DownsampleStrategy.NONE,
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objectFit: ImageFit.Contain,
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autoResize:true
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}
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})
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.height(300)
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.width(300)
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.borderWidth(1)
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.borderColor(Color.Pink)
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}
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}
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.height('100%')
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.width('100%')
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}
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}
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After Width: | Height: | Size: 678 KiB |
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/*
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* Copyright (C) 2024 Huawei Device Co., Ltd.
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* Licensed under the Apache License, Version 2.0 (the "License");
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* you may not use this file except in compliance with the License.
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* You may obtain a copy of the License at
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*
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* http://www.apache.org/licenses/LICENSE-2.0
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*
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* Unless required by applicable law or agreed to in writing, software
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* distributed under the License is distributed on an "AS IS" BASIS,
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* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
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* See the License for the specific language governing permissions and
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* limitations under the License.
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*/
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import { lang } from '@kit.ArkTS';
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import { SampleSizeRounding } from './downsampleUtils';
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type ISendable = lang.ISendable;
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export interface BaseDownsampling extends ISendable {
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getName(): string
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getScaleFactor(sourceWidth: number, sourceHeight: number, requestWidth: number, requestHeight: number): number
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getSampleSizeRounding(sourceWidth: number, sourceHeight: number, requestWidth: number, requestHeight: number): SampleSizeRounding
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}
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/*
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* Copyright (C) 2024 Huawei Device Co., Ltd.
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* Licensed under the Apache License, Version 2.0 (the "License");
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* you may not use this file except in compliance with the License.
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* You may obtain a copy of the License at
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*
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* http://www.apache.org/licenses/LICENSE-2.0
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*
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* Unless required by applicable law or agreed to in writing, software
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* distributed under the License is distributed on an "AS IS" BASIS,
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* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
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* See the License for the specific language governing permissions and
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* limitations under the License.
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*/
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import { BaseDownsampling } from './BaseDownsampling';
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import { highestOneBit,SampleSizeRounding } from './downsampleUtils';
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//FitCenter类实现DownsampleStartegy
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@Sendable
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export class FitCenter implements BaseDownsampling {
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getName() {
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return "FitCenter"
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}
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//实现 getScaleFactor 方法
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getScaleFactor(sourceWidth: number, sourceHeight: number, requestedWidth: number, requestedHeight: number,autoResize?:boolean): number {
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const IS_BITMAP_FACTORY_SCALING_SUPPORTED = autoResize; //这里需要根据实际情况设置这个值
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if (IS_BITMAP_FACTORY_SCALING_SUPPORTED) {
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const widthPercentage = requestedWidth / sourceWidth
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const heightPercentage = requestedHeight / sourceHeight
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return Math.min(widthPercentage, heightPercentage)
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}else{
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//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
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const maxIntegerFactor = Math.max(sourceHeight/requestedHeight, sourceWidth/requestedWidth);
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const a = maxIntegerFactor === 0 ? 1 : 1 / highestOneBit(maxIntegerFactor)
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return a;
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}
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}
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//实现 getSampleSizeRounding 方法
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getSampleSizeRounding(sourceWidth: number, sourceHeight: number, requestedWidth: number, requestedHeight: number,autoResize?:boolean): number {
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const IS_BITMAP_FACTORY_SCALING_SUPPORTED = autoResize; //这里需要根据实际情况设置这个值
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if (!IS_BITMAP_FACTORY_SCALING_SUPPORTED) {
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return 0;
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} else {
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// 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
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// MEMORY 折中方案,他让我们更喜欢两者中较大的那个
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return SampleSizeRounding.MEMORY;
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}
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}
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}
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//None 类实现 DownsampleStrategy 接口
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@Sendable
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export class None implements BaseDownsampling{
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getName(): string{
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return "DownsampleNone"
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}
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//实现 getScaleFactor 方法
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public getScaleFactor(sourceWidth: number, sourceHeight: number, requestedWidth: number, requestedHeight: number): number {
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//不进行任何下采样，缩放因子为 1
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return 1;
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}
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//实现 getSampleSizeRounding 方法
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public getSampleSizeRounding(sourceWidth: number, sourceHeight: number, requestedWidth: number, requestedHeight: number): SampleSizeRounding {
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//总是返回 QUALITY
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return SampleSizeRounding.QUALITY
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}
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}
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/*宽高进行等比缩放宽高里面最小的比例先放进去
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然后再更据原图的缩放比去适配另一边*/
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@Sendable
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export class CenterOutside implements BaseDownsampling {
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getName() {
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return "CenterOutside"
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}
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//实现 getScaleFactor 方法
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getScaleFactor(sourceWidth: number, sourceHeight: number, requestedWidth: number, requestedHeight: number): number {
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const widthPercentage = requestedWidth / sourceWidth;
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const heightPercentage = requestedHeight / sourceHeight;
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//返回宽度和高度比例中最大的值
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return Math.max(widthPercentage, heightPercentage);
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}
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//实现 getSampleSizeRounding 方法
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getSampleSizeRounding(sourceWidth: number, sourceHeight: number, requestedWidth: number, requestedHeight: number): SampleSizeRounding {
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//根据 CenterOutside 的逻辑，总是返回 QUALITY
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return SampleSizeRounding.QUALITY;
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}
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}
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/*请求尺寸大于实际尺寸不进行放大,按照原图展示*/
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@Sendable
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export class Atleast implements BaseDownsampling {
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//构造函数
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constructor(){
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//TypeScript 默认构造函数不需要特殊标记
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}
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getName() {
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return "AtLeast"
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}
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//实现 getScaleFactor 方法
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public getScaleFactor(sourceWidth: number, sourceHeight: number, requestedWidth: number, requestedHeight: number): SampleSizeRounding {
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//计算最小整数因子
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const minIntegerFactor = Math.min(sourceHeight / requestedHeight, sourceWidth / requestedWidth)
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//根据最小整数因子计算缩放因子
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return minIntegerFactor === 0 ? 1 : 1 / highestOneBit(minIntegerFactor);
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}
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//实现 getSampleSizeRounding 方法
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public getSampleSizeRounding(sourceWidth: number, sourceHeight: number, requestedWidth: number, requestedHeight: number): SampleSizeRounding {
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//总是返回 QUALITY
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return SampleSizeRounding.QUALITY
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}
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}
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/*请求尺寸大于实际尺寸不进行放大,按照原图展示*/
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@Sendable
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export class AtMost implements BaseDownsampling {
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getName() {
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return "AtMost"
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}
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//实现 getScaleFactor 方法
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getScaleFactor(sourceWidth: number, sourceHeight: number, requestedWidth: number, requestedHeight: number): number {
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const maxIntegerFactor = Math.ceil(Math.max(sourceHeight / requestedHeight, sourceWidth / requestedWidth));
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let lesserOrEqualSampleSize = Math.max(1, highestOneBit(maxIntegerFactor));
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let greaterOrEqualSampleSize = lesserOrEqualSampleSize
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// if (lesserOrEqualSampleSize < maxIntegerFactor) {
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// let greaterOrEqualSampleSize = lesserOrEqualSampleSize <<= 1; // lest shift by 1
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// }
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greaterOrEqualSampleSize = lesserOrEqualSampleSize << (lesserOrEqualSampleSize < maxIntegerFactor ? 1 : 0)
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//返回缩放因子
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return 1 / greaterOrEqualSampleSize
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}
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highestOneBit(i: number): number {
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i |= (i >> 1);
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i |= (i >> 2);
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i |= (i >> 4);
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i |= (i >> 8);
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i |= (i >> 16);
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return i - (i >>> 1);
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}
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//实现 getSampleSizeRounding 方法
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getSampleSizeRounding(sourceWidth: number, sourceHeight: number, requestedWidth: number, requestHeight: number): SampleSizeRounding {
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//根据 AtMost 的逻辑，总是返回 MEMORY
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return SampleSizeRounding.MEMORY
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}
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}
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/*宽高进行等比缩放宽高里面最大的比例先放进去
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然后再更据原图的缩放比去适配另一边*/
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@Sendable
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export class CenterInside implements BaseDownsampling {
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getName() {
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return "CenterInside"
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}
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//实现 getScaleFactor 方法
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getScaleFactor(sourceWidth: number, sourceHeight: number, requestedWidth: number, requestedHeight: number,autoResize?:boolean): number {
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//获取 FIT_CENTER 的缩放因子
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const fitCenterScaleFactor : ESObject = this.getScale(sourceWidth,sourceHeight,requestedWidth,requestedHeight,autoResize);
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//实现 getScaleFactor 方法
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//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
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return Math.min(1,fitCenterScaleFactor);
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}
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getScale(sourceWidth: number, sourceHeight: number, requestedWidth: number, requestedHeight: number,autoResize?:boolean): number {
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const IS_BITMAP_FACTORY_SCALING_SUPPORTED = autoResize; //这里需要根据实际情况设置这个值
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if (IS_BITMAP_FACTORY_SCALING_SUPPORTED) {
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const widthPercentage = requestedWidth / sourceWidth
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const heightPercentage = requestedHeight / sourceHeight
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return Math.min(widthPercentage, heightPercentage)
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}else{
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//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
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const maxIntegerFactor = Math.max(sourceHeight/requestedHeight, sourceWidth/requestedWidth);
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return maxIntegerFactor === 0 ? 1 : 1 / highestOneBit(maxIntegerFactor);
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}
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}
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//实现 getSampleSizeRounding 方法
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getSampleSizeRounding(sourceWidth: number, sourceHeight: number, requestedWidth: number, requestedHeight: number,autoResize?:boolean): SampleSizeRounding {
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//如果缩放因子为 1，表示没有缩放，优先选择质量
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if (this.getScaleFactor(sourceWidth,sourceHeight,requestedWidth,requestedHeight,autoResize) === 1) {
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return SampleSizeRounding.QUALITY
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}
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//否则，使用 FIL_CENTER 的 SampleSizeRounding 值
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return this.getSampleSize(sourceWidth,sourceHeight,requestedWidth,requestedHeight);
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}
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highestOneBit(i: number): number {
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i |= (i >> 1);
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i |= (i >> 2);
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i |= (i >> 4);
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i |= (i >> 8);
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i |= (i >> 16);
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return i - (i >>> 1);
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}
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//实现 getSampleSizeRounding 方法
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getSampleSize(sourceWidth: number, sourceHeight: number, requestedWidth: number, requestedHeight: number,autoResize?:boolean): SampleSizeRounding {
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const IS_BITMAP_FACTORY_SCALING_SUPPORTED = autoResize; //这里需要根据实际情况设置这个值
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if (IS_BITMAP_FACTORY_SCALING_SUPPORTED) {
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return 0;
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} else {
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// 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
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// MEMORY 折中方案,他让我们更喜欢两者中较大的那个
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//
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// }
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return SampleSizeRounding.MEMORY;
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}
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}
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}
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export enum DownsampleStrategy{
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AT_LEAST,
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AT_MOST,
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FIT_CENTER,
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CENTER_INSIDE,
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CENTER_OUTSIDE,
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NONE,
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}
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@ -0,0 +1,175 @@
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/*
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* Copyright (C) 2024 Huawei Device Co., Ltd.
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* 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.
|
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*/
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import {
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Atleast,
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AtMost,
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CenterInside,
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CenterOutside,
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DownsampleStrategy,
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FitCenter,
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None,
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} from './DownsampleStartegy';
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import { highestOneBit, SampleSizeRounding } from './downsampleUtils';
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export interface calculateScaleType {
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targetWidth: number,
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targetHeight: number
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}
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export class Downsampler {
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calculateScaling(
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typeValue: string | null,
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sourceHeight: number, //原始宽高
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sourceWidth: number | undefined,
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//原始宽高 7106
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requestHeight: number, //请求宽高
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requestWidth: number, //请求宽高
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downsampType: DownsampleStrategy | undefined,
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autoResize:boolean |undefined
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): calculateScaleType {
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let degreesToRotate: ESObject = 0; //获取旋转角度
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const fileType = typeValue //获取图片类型
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let powerOfTwoWidth: number | null = null;
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let powerOfTwoHeight: number | null = null;
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let targetWidth: number = 0
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let targetHeight: number = 0
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if (sourceHeight <= 0 || sourceWidth == undefined || sourceWidth == null || sourceWidth <= 0) {
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throw new Error("Cannot found width or height");
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}
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let orientedSourceWidth = sourceWidth;
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let orientedSourceHeight = sourceHeight;
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if (this.isRotationRequired(degreesToRotate)) {
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orientedSourceWidth = sourceHeight;
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orientedSourceHeight = sourceWidth;
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}
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if (requestWidth && !requestHeight) {
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targetWidth = this.round((requestHeight) * orientedSourceWidth / orientedSourceHeight)
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} else if (requestHeight && !requestWidth) {
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targetHeight = this.round((requestWidth) * orientedSourceHeight / orientedSourceWidth)
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} else if (requestHeight && requestWidth) {
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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)
|
||||
}
|
||||
}
|
||||
|
|
@ -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);
|
||||
}
|
||||
Loading…
Reference in New Issue