如何将BitmapData对象直接上传到我的服务器？

var byteArray:ByteArray = bitmapData.encode(new Rectangle(0, 0, bitmapData.width, bitmapData.height), new PNGEncoderOptions());
var base64String:String = Base64.encodeByteArray(byteArray);

var request:URLRequest = new URLRequest("https://your-server.com/upload.php");
request.method = URLRequestMethod.POST;
var variables:URLVariables = new URLVariables();
variables.imageData = base64String;
request.data = variables;

var loader:URLLoader = new URLLoader();
loader.addEventListener(Event.COMPLETE, onComplete);
loader.addEventListener(IOErrorEvent.IO_ERROR, onError);
loader.load(request);

function onComplete(event:Event):void {
    trace("上传成功：", event.target.data);
}

function onError(event:IOErrorEvent):void {
    trace("上传失败：", event.text);
}

<?php
$imageData = $_POST['imageData'];
$binaryData = base64_decode($imageData);
header('Content-Type: bitmap; charset=utf-8');
$filename = 'uploaded_image.png';
file_put_contents($filename, $binaryData);
echo '图像已成功上传';
?>