如何将PixelMap压缩到指定大小

@Entry 
@Component 
struct Index { 
  ...... 
  
  // 压缩图片并保存到相册 
  async compression(file: fs.File, data?: ArrayBuffer, size: number = 30, quality: number = 99) : Promise<ArrayBuffer> { 
    if (data) { 
      const currentSize = data.byteLength / 1024; 
      if (currentSize <= size || quality === 1) { 
        return data; 
      } 
    } 
    const imagePackerApi = image.createImagePacker(); 
    const imageSourceApi = image.createImageSource(file.fd); 
    let packOpts: image.PackingOption = { format: "image/jpeg", quality: quality }; 
  
    let result = await imagePackerApi.packing(imageSourceApi, packOpts); 
    if (data && result.byteLength === data.byteLength){ 
      return result; 
    } 
    return this.compression(file, result, size, quality - 1); 
  } 
}