Here is the part of the code to make the post directly using socket, with the following limitations :

- user must have flash player 10 installed

- the load method of FileRefence is limited to 100MB

- there is no way to have feedback because there is no event when uploading files by socket with flash

import com.adobe.net.URI;
import com.adobe.serialization.json.JSON;
import org.httpclient.events.HttpDataListener;
import org.httpclient.events.HttpResponseEvent;
import org.httpclient.http.multipart.Multipart;
import org.httpclient.http.multipart.Part;
import org.httpclient.HttpClient;
import org.httpclient.Log;
 
private var fileRef:FileReference;
private const TOKEN:String = "your write token here";
private const UPLOAD_CALL:String = "http://api.brightcove.com/services/post";
private var listener:HttpDataListener; 
 
........ 
 
private function onClick(e:MouseEvent):void {
	fileRef = new FileReference();
	var imagesFilter:FileFilter = new FileFilter("Videos", "*.3g2;*.3gp;*.asf;*.avi;*.flv;*.f4v;*.m4v;*.mov;*.mp4;*.mpeg;*.mpg;*.qt;*.wmv");	       
        fileRef.addEventListener(Event.SELECT, onFileSelectedLocalLoad);
        fileRef.browse([imagesFilter]);
}

private function onFileSelectedLocalLoad(e:Event):void {
	fileRef.addEventListener(Event.COMPLETE, onLocalLoadComplete);
        fileRef.load();
}
		
private function onLocalLoadComplete(e:Event):void {
	Log.level = Log.DEBUG;
	var charles:URI;
	// uncomment to use Charles debugging proxy
        // charles = new URI("http://localhost:8888");
	var http:HttpClient = new HttpClient(charles, 600000);
 	var uri:URI = new URI(UPLOAD_CALL);
	var jsonParams:Object = new Object();
	jsonParams.method = "create_video";
	jsonParams.params = { token:TOKEN, video:{name:fileRef.name, shortDescription:"Test video", tags:["gibbous","foo"]}};
	var multipart:Multipart = new Multipart([new Part('json', JSON.encode(jsonParams)), new Part('file', fileRef.data, "video/octet-stream", [ { name:"filename", value:fileRef.name } ])]);
	listener = new HttpDataListener();
	listener.onComplete = onPostComplete;
	listener.onDataComplete = onPostDataComplete;
        http.listener = listener; 
	http.postMultipart(uri, multipart);
}

private function onPostComplete(event:HttpResponseEvent):void{
	trace(event);
	trace(event.response);
}