HarmonyOS 鸿蒙Next AVPlayer是什么获取本地相册里面的视频的缩略图

AVPlayer 是 功能较完善的音视频播放ArkTS/JS API，集成了流媒体和本地资源解析，媒体资源解封装，视频解码和渲染功能，适用于对媒体资源进行端到端播放的场景，可直接播放mp4、mkv等格式的视频文件

获取视频缩放图demo 获取到的缩放图为pixelMap 只需使用image组件展示即可

// 获取应用文件路径
let context = this as common.UIAbilityContext;
let cacheDir = context.cacheDir;

@Entry
@Component
struct Index {
  @State message: string = 'Hello World';
  @State pixelMap: image.PixelMap | undefined = undefined;

  build() {
    RelativeContainer() {
      Text(this.message)
        .id('HelloWorld')
        .fontSize(50)
        .fontWeight(FontWeight.Bold)
        .alignRules({
          center: { anchor: '__container__', align: VerticalAlign.Center },
          middle: { anchor: '__container__', align: HorizontalAlign.Center }
        })
        .onClick(() => {
          this.downLoad()
        })
        .height('100%')
        .width('100%')
      Image(this.pixelMap).width(300).height(300)
        .margin({
          top: 20
        })
    }
  }

  downLoad() {
    try {
      request.downloadFile(context, {
        url: 'https://sns-video-bd.xhscdn.com/stream/110/258/01e602cadc11542d010370038e7ae8b418_258.mp4',
        filePath: cacheDir + '/b.mp4'
      }).then((downloadTask: request.DownloadTask) => {
        downloadTask.on('complete', () => {
          console.info('download complete');
          this.testFetchFrameByTime(cacheDir + '/b.mp4')
        })
      }).catch((err: BusinessError) => {
        console.error(`Invoke downloadTask failed, code is ${err.code}, message is ${err.message}`);
      });
    } catch (error) {
      let err: BusinessError = error as BusinessError;
      console.error(`Invoke downloadFile failed, code is ${err.code}, message is ${err.message}`);
    }
  }

  // 获取缩略图
  async testFetchFrameByTime(filePath: string) {
    // 创建AVImageGenerator对象
    let avImageGenerator: media.AVImageGenerator = await media.createAVImageGenerator()
    let file = fs.openSync(filePath, fs.OpenMode.READ_ONLY);
    let avFileDescriptor: media.AVFileDescriptor = { fd: file.fd };
    avImageGenerator.fdSrc = avFileDescriptor;
    // 初始化入参
    let timeUs = 0
    let queryOption = media.AVImageQueryOptions.AV_IMAGE_QUERY_NEXT_SYNC
    let param: media.PixelMapParams = {
      width: 300,
      height: 400,
    }
    // 获取缩略图（promise模式）
    this.pixelMap = await avImageGenerator.fetchFrameByTime(timeUs, queryOption, param)
    // 释放资源（promise模式）
    avImageGenerator.release()
    console.info(`release success.`);
    fs.closeSync(file);
  }
}

获取视频缩放图demo：https://developer.huawei.com/consumer/cn/doc/harmonyos-guides-V5/avimagegenerator-V5

image组件参考指南：https://developer.huawei.com/consumer/cn/doc/harmonyos-references-V5/ts-basic-components-image-V5#image-1

AVPlayer 参考指南：https://developer.huawei.com/consumer/cn/doc/harmonyos-references-V5/js-apis-media-V5#avplayer9