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createImageReceiver(): image.ImageReceiver { 
let receiver: image.ImageReceiver = image.createImageReceiver(cameraWidth, cameraHeight, 2000, 8); 
receiver.on(‘imageArrival’, () => { 
receiver.readNextImage((err: BusinessError, nextImage: image.Image) => { 
if (err || nextImage === undefined) { 
return; 
} 
nextImage.getComponent(image.ComponentType.JPEG, async (err: BusinessError, imgComponent: image.Component) => { 
if (err || imgComponent === undefined) { 
return; 
} 
if (imgComponent.byteBuffer as ArrayBuffer) { 
let sourceOptions : image.SourceOptions = { 
sourceDensity: 120, 
sourcePixelFormat: 8, // NV21 
sourceSize: { 
height: previewProfilesObj3.size.height, 
width: previewProfilesObj3.size.width 
} 
} 
let imageResource=image.createImageSource(imgComponent.byteBuffer,sourceOptions) 
let decodingOptions: image.DecodingOptions = { 
editable: true, 
desiredPixelFormat: 3, 
} 
this.pixma=await imageResource.createPixelMap(decodingOptions) 
const imagePackerApi = image.createImagePacker(); 
let packOpts: image.PackingOption = { format: “image/jpeg”, quality: 98 }; 
const context: Context = getContext(this); 
const path1: string = context.cacheDir + “/pixel_map86695.jpg”; 
imagePackerApi.packing(imageResource, packOpts).then((data: ArrayBuffer) => { 
// data 为打包获取到的文件流，写入文件保存即可得到一张图片 
if (data) { 
let buf: buffer.Buffer = buffer.from(data ); 
let base64Url: string = buf.toString(‘base64url’, 0, buf.length); 
console.log(‘66666’+JSON.stringify(base64Url)) 
 
          let file = fs.openSync(path1, fs.OpenMode.READ_WRITE | fs.OpenMode.CREATE); 
 
          fs.write(file.fd, data).then(async (writeLen) => { 
            console.info("write data to file succeed and size is:" + writeLen); 
fs.closeSync(file); 
}).catch((err: BusinessError) => { 
console.info("write data to file failed with error message: " + err.message + ", error code: " + err.code); 
}); 
} 
}).catch((error: BusinessError) => { 
console.error('Failed to pack the image. And the error is: ’ + error); 
}) 
this.pixelmap=await imageResource.createPixelMap(); 
} else { 
return; 
} 
}) 
}) 
}) 
return receiver; 
}