HarmonyOS 请问下如何将图片进行压缩操作

参考以下代码和demo链接：https://gitee.com/harmonyos-cases/cases/tree/master/CommonAppDevelopment/feature/imagecompression

let uri = 'xxxx' ;
let file = fs.openSync(uri, fs.OpenMode.READ_ONLY);
console.info('file fd:' + file.fd);
const imageSource: image.ImageSource = image.createImageSource(file.fd);
let decodingOptions: image.DecodingOptions = {
  editable: true,
  desiredPixelFormat: 3,
  desiredSize: { width: 1, height: 2 },
}
this.pixelMap = await imageSource.createPixelMap(decodingOptions);