/**
* Copyright j2e ( http://wonderfl.net/user/j2e )
* MIT License ( http://www.opensource.org/licenses/mit-license.php )
* Downloaded from: http://wonderfl.net/c/uys7
*/
package
{
import flash.display.Bitmap;
import flash.display.BitmapData;
import flash.display.BlendMode;
import flash.display.Sprite;
import flash.display.MovieClip;
import flash.events.ActivityEvent;
import flash.events.Event;
import flash.geom.Point;
import flash.geom.Rectangle;
import flash.media.Camera;
import flash.media.Video;
import flash.geom.Matrix;
import flash.geom.Point;
import flash.geom.Rectangle;
import flash.media.Video;
public class FrameDiff extends Sprite
{
private var cam:Camera = Camera.getCamera();
private var sw:Number = 640;
private var sh:Number = 480;
private var pnt:Point = new Point(0,0);
private var rect:Rectangle = new Rectangle(0,0,sw,sh);
private var video:Video = new Video(sw, sh);
private var canvas:BitmapData = new BitmapData(sw, sh, false, 0x000000);
private var buffer:BitmapData = new BitmapData(sw, sh, false, 0x000000);
private var feed :BitmapData = new BitmapData(sw, sh, false, 0x000000);
private var prev :BitmapData = new BitmapData(sw, sh, false, 0x000000);
private var frame:Bitmap = new Bitmap(canvas, "auto", true);
private var _bmdNew:BitmapData; // bitmapdata from the current pass of the video
private var _bmdOld:BitmapData; // bitmapdata from the previous pass of the video
private var _point:Point; // point used for various filters
private var _pos:Point // point used to keep track of general motion
private var _matrix:Matrix; // matrix used to flip the source video
public function FrameDiff()
{
addChild(frame);
cam.setMode(sw, sh, 30);
video.attachCamera(cam);
cam.addEventListener(ActivityEvent.ACTIVITY, onActivityStart);
}
private function onActivityStart(evt:ActivityEvent):void
{
addEventListener(Event.ENTER_FRAME, VideoTracker);
cam.removeEventListener(ActivityEvent.ACTIVITY, onActivityStart);
}
private function onRun(evt:Event):void
{
buffer.draw(video);
//feed.copyPixels(buffer, rect, pnt);
buffer.draw(prev, null, null, BlendMode.DIFFERENCE);
//prev.draw(video);
canvas.copyPixels(buffer, rect, pnt);
}
private function VideoTracker(src:Video): void
{
// setup default settings
video = src;
_point = new Point();
_pos = new Point();
_bmdNew = new BitmapData(src.width, src.height, false, 0);
_bmdOld = new BitmapData(src.width, src.height, false, 0);
//_blur = new BlurFilter(5, 5);
// add the new bitmap data to the display in case we want to view it to see whats going on
addChild(frame);
// flip the video input
setupFlipMatrix();
canvas.copyPixels(_bmdNew, rect, pnt);
}
// track the video
public function track():void
{
_bmdNew.draw(video, _matrix); // draw the source video and flip the input with the matrix we setup
_bmdNew.draw(_bmdOld, null, null, BlendMode.DIFFERENCE); // draw the old frames video on top with a difference blend mode
//_bmdNew.applyFilter(_bmdNew, _bmdNew.rect, _point, _blur); // apply a blur filter to soften the areas we are checking
// we now run a threashold over the current bitmapdata so that we can isolate all areas of interest
// anything over dark grey will be turned to white so we can track it later on
//_bmdNew.threshold(_bmdNew, _bmdNew.rect, _point, '>', 0xFF333333, 0xFFFFFFFF);
// update the old bitmpadata
_bmdOld.draw(video, _matrix);
// using the bitmapdata method getColorBoundsRect command we can get the rectangle bounds of
// a certain colour we are after tracking, in this instance its the white from the threashold
//var bounds:Rectangle = _bmdNew.getColorBoundsRect(0xFFFFFFFF, 0xFFFFFFFF, true);
// update the position of the general movement, do this by centering it around the
// middle of the bounds rectangle
//var x:Number = bounds.x + bounds.width*.5;
//var y:Number = bounds.y + bounds.height*.5;
// check for zero values, if we get some then dont update the position
//if (x > 0 && y > 0)
//{
// _pos.x = x;
// _pos.y = y;
//}
}
// setup matrix to flip the source video so that what we track is relative to
// the users movement to the screen
private function setupFlipMatrix():void
{
_matrix = new Matrix(); // new matrix
_matrix.translate(-video.width, 0); // move left by the width of the source video
_matrix.scale(-1, 1); // flip the scaleX
}
// return a copy of the position point
public function get pos():Point { return _pos.clone(); }
}
}
