在我制作的整个游戏中，我都有需要播放的小电影剪辑。目前我正在将它们制作成后效并将它们导出为 FLV 文件并将它们嵌入到时间线中，制作一个 moviclip 符号来播放它们。
但这显然是一场灾难。这样我得到非常小的电影剪辑，但它们根本不会垃圾收集。所以它一直存储在内存中。如果我将它们转换成 SWF，文件会变大 10 倍，对于 2.4 mb flv 文件，文件会高达 24 mb。以这种方式使用它真的很令人沮丧。
有人可以建议一种在 actionscript 3 中处理视频/剪辑的方法吗？我不需要对这些影片剪辑进行任何控制，它们用作过场动画。
Adobe 推出了StageVideo，利用硬件加速实现高性能视频播放。
为了减轻在 Video 对象中渲染视频对性能的影响，Adobe 引入了舞台视频作为渲染视频的新方法。这种方法充分利用了底层视频硬件。结果是 CPU 上的负载要低得多，这意味着功能较弱的设备上的帧速率更高，内存使用量也更少。
package
{
import flash.display.Bitmap;
import flash.display.BitmapData;
import flash.display.DisplayObject;
import flash.display.Loader;
import flash.display.Shape;
import flash.display.Sprite;
import flash.display.StageAlign;
import flash.display.StageDisplayState;
import flash.display.StageScaleMode;
import flash.events.Event;
import flash.events.FullScreenEvent;
import flash.events.KeyboardEvent;
import flash.events.MouseEvent;
import flash.events.NetStatusEvent;
import flash.events.StageVideoAvailabilityEvent;
import flash.events.StageVideoEvent;
import flash.events.TimerEvent;
import flash.events.VideoEvent;
import flash.geom.Rectangle;
import flash.media.SoundTransform;
import flash.media.StageVideo;
import flash.media.StageVideoAvailability;
import flash.media.Video;
import flash.net.NetConnection;
import flash.net.NetStream;
import flash.system.LoaderContext;
import flash.text.TextField;
import flash.text.TextFieldAutoSize;
import flash.text.TextFormat;
import flash.ui.Keyboard;
/**
*
* @author Thibault Imbert
*
*/
[SWF(frameRate="1", backgroundColor="#000000")]
public class SimpleStageVideo extends Sprite
{
private static const FILE_NAME:String = "video-file.mov";
private static const INTERVAL:Number = 500;
private static const BORDER:Number = 20;
private var legend:TextField = new TextField();
private var sv:StageVideo;
private var nc:NetConnection;
private var ns:NetStream;
private var rc:Rectangle;
private var video:Video;
private var thumb:Shape;
private var interactiveThumb:Sprite;
private var totalTime:Number;
private var videoWidth:int;
private var videoHeight:int;
private var outputBuffer:String = new String();
private var rect:Rectangle = new Rectangle(0, 0, 0, BORDER);
private var videoRect:Rectangle = new Rectangle(0, 0, 0, 0);
private var gotStage:Boolean;
private var stageVideoInUse:Boolean;
private var classicVideoInUse:Boolean;
private var accelerationType:String;
private var infos:String = new String();
private var available:Boolean;
private var inited:Boolean;
private var played:Boolean;
private var container:Sprite;
/**
*
*
*/
public function SimpleStageVideo()
{
// Make sure the app is visible and stage available
addEventListener(Event.ADDED_TO_STAGE, onAddedToStage);
}
/**
*
* @param event
*
*/
private function onAddedToStage(event:Event):void
{
// Scaling
stage.scaleMode = StageScaleMode.NO_SCALE;
stage.align = StageAlign.TOP_LEFT;
legend.autoSize = TextFieldAutoSize.LEFT;
// Debug infos
legend.multiline = true;
legend.background = true;
legend.backgroundColor = 0xFFFFFFFF;
addChild(legend);
// Thumb seek Bar
thumb = new Shape();
interactiveThumb = new Sprite();
interactiveThumb.addChild(thumb);
addChild(interactiveThumb);
// Connections
nc = new NetConnection();
nc.connect(null);
ns = new NetStream(nc);
ns.addEventListener(NetStatusEvent.NET_STATUS, onNetStatus);
ns.client = this;
// Screen
video = new Video();
video.smoothing = true;
// Video Events
// the StageVideoEvent.STAGE_VIDEO_STATE informs you if StageVideo is available or not
stage.addEventListener(StageVideoAvailabilityEvent.STAGE_VIDEO_AVAILABILITY, onStageVideoState);
// in case of fallback to Video, we listen to the VideoEvent.RENDER_STATE event to handle resize properly and know about the acceleration mode running
video.addEventListener(VideoEvent.RENDER_STATE, videoStateChange);
// Input Events
stage.addEventListener(KeyboardEvent.KEY_DOWN, onKeyDown);
stage.addEventListener(Event.RESIZE, onResize);
stage.addEventListener(MouseEvent.CLICK, onClick);
}
/**
*
* @param event
*
*/
private function onNetStatus(event:NetStatusEvent):void
{
if ( event.info == "NetStream.Play.StreamNotFound" )
legend.text = "Video file passed, not available!";
}
/**
*
* @param event
*
*/
private function onFrame(event:Event):void
{
var ratio:Number = (ns.time / totalTime) * (stage.stageWidth - (BORDER << 1));
rect.width = ratio;
thumb.graphics.clear();
thumb.graphics.beginFill(0xFFFFFF);
thumb.graphics.drawRect(rect.x, rect.y, rect.width, rect.height);
}
/**
*
* @param event
*
*/
private function onClick(event:MouseEvent):void
{
if ( event.stageY >= interactiveThumb.y - BORDER && event.stageX <= stage.stageWidth - BORDER )
{
var seekTime:Number = (stage.mouseX - BORDER) * ( totalTime / (stage.stageWidth - (BORDER << 1) ) );
ns.seek( seekTime );
}
}
/**
*
* @param event
*
*/
private function onKeyDown(event:KeyboardEvent):void
{
if ( event.keyCode == Keyboard.O )
{
if ( available )
// We toggle the StageVideo on and off (fallback to Video and back to StageVideo)
toggleStageVideo(inited=!inited);
} else if ( event.keyCode == Keyboard.F )
{
stage.displayState = StageDisplayState.FULL_SCREEN;
} else if ( event.keyCode == Keyboard.SPACE )
{
ns.togglePause();
}
}
/**
*
* @param width
* @param height
* @return
*
*/
private function getVideoRect(width:uint, height:uint):Rectangle
{
var videoWidth:uint = width;
var videoHeight:uint = height;
var scaling:Number = Math.min ( stage.stageWidth / videoWidth, stage.stageHeight / videoHeight );
videoWidth *= scaling, videoHeight *= scaling;
var posX:uint = stage.stageWidth - videoWidth >> 1;
var posY:uint = stage.stageHeight - videoHeight >> 1;
videoRect.x = posX;
videoRect.y = posY;
videoRect.width = videoWidth;
videoRect.height = videoHeight;
return videoRect;
}
/**
*
*
*/
private function resize ():void
{
if ( stageVideoInUse )
{
// Get the Viewport viewable rectangle
rc = getVideoRect(sv.videoWidth, sv.videoHeight);
// set the StageVideo size using the viewPort property
sv.viewPort = rc;
} else
{
// Get the Viewport viewable rectangle
rc = getVideoRect(video.videoWidth, video.videoHeight);
// Set the Video object size
video.width = rc.width;
video.height = rc.height;
video.x = rc.x, video.y = rc.y;
}
interactiveThumb.x = BORDER, interactiveThumb.y = stage.stageHeight - (BORDER << 1);
legend.text = infos;
}
/**
*
* @param evt
*
*/
public function onMetaData ( evt:Object ):void
{
totalTime = evt.duration;
stage.addEventListener(Event.ENTER_FRAME, onFrame);
}
/**
*
* @param event
*
*/
private function onStageVideoState(event:StageVideoAvailabilityEvent):void
{
// Detect if StageVideo is available and decide what to do in toggleStageVideo
toggleStageVideo(available = inited = (event.availability == StageVideoAvailability.AVAILABLE));
}
/**
*
* @param on
*
*/
private function toggleStageVideo(on:Boolean):void
{
infos = "StageVideo Running (Direct path) : " + on + "\n";
// If we choose StageVideo we attach the NetStream to StageVideo
if (on)
{
stageVideoInUse = true;
if ( sv == null )
{
sv = stage.stageVideos[0];
sv.addEventListener(StageVideoEvent.RENDER_STATE, stageVideoStateChange);
}
sv.attachNetStream(ns);
if (classicVideoInUse)
{
// If we use StageVideo, we just remove from the display list the Video object to avoid covering the StageVideo object (always in the background)
stage.removeChild ( video );
classicVideoInUse = false;
}
} else
{
// Otherwise we attach it to a Video object
if (stageVideoInUse)
stageVideoInUse = false;
classicVideoInUse = true;
video.attachNetStream(ns);
stage.addChildAt(video, 0);
}
if ( !played )
{
played = true;
ns.play(FILE_NAME);
}
}
/**
*
* @param event
*
*/
private function onResize(event:Event):void
{
resize();
}
/**
*
* @param event
*
*/
private function stageVideoStateChange(event:StageVideoEvent):void
{
infos += "StageVideoEvent received\n";
infos += "Render State : " + event.status + "\n";
resize();
}
/**
*
* @param event
*
*/
private function videoStateChange(event:VideoEvent):void
{
infos += "VideoEvent received\n";
infos += "Render State : " + event.status + "\n";
resize();
}
}
}