How to save screenshots with its exif data edited by user (in Flex 4.6 application)? - actionscript-3

Question

I need to develop a web application which captures snapshot of live stream video in Spark VideoPlayer and then ask for user input regarding EXIF tags then save the image along with its EXIF data to the local drive. An early response will be highly appreciated. Thanks
I have used the following code, but so far have not been succeed in editing the exif data into image header
<s:TitleWindow xmlns:fx="http://ns.adobe.com/mxml/2009"
xmlns:s="library://ns.adobe.com/flex/spark"
xmlns:mx="library://ns.adobe.com/flex/mx"
width="400" height="410" title="Snapshot"
close="titlewindow1_closeHandler(event)"
windowMoveStart="basewidget1_widgetConfigLoadedHandler(event)"
>
<fx:Script>
<![CDATA[
import mx.controls.Alert;
import mx.events.CloseEvent;
import mx.graphics.ImageSnapshot;
import mx.graphics.codec.*;
import mx.managers.PopUpManager;
[Bindable]
public var saveName:String ="";
protected function basewidget1_widgetConfigLoadedHandler(event:Event):void
{
}
protected function titlewindow1_closeHandler(event:CloseEvent):void
{
PopUpManager.removePopUp(this);
}
protected function SaveImg_clickHandler(event:MouseEvent):void
{
var d:Date = new Date();
var image:ImageSnapshot = ImageSnapshot.captureImage(pic1, 300, new PNGEncoder());
var file:FileReference = new FileReference();
file.save(image.data, saveName+" "+d.date+ "-"+d.month +"-"+d.fullYear + d.hours+ d.minutes + d.seconds);
}
]]>
</fx:Script>
<fx:Declarations>
</fx:Declarations>
<s:VGroup width="100%" horizontalAlign="center" verticalAlign="middle">
<s:Image id="pic1" x="41" y="34" width="100%" height="300"/>
<s:HGroup width="100%" height="30" horizontalAlign="center" verticalAlign="middle">
<s:TextInput id="Title" x="35" width="60" prompt="Title"/>
<mx:DateField id="DateTaken" x="78" width="137"/>
<s:TextInput id="info" width="80" prompt="Info"/>
<s:TextInput id="User Comments" width="80" prompt="User Comments" restrict="0-9,."/>
</s:HGroup>
</s:VGroup>
<s:HGroup x="3" y="348" width="100%" height="30" horizontalAlign="center" verticalAlign="middle">
<s:Button id="SaveImg0" label="Save" click="SaveImg_clickHandler(event)"/>
</s:HGroup>