我需要将一个可以播放全屏视频的小 Flash 站点转换为独立投影仪，该投影仪将在 Windows 7 或 xp 中运行，并且必须以 1080p 播放视频
这里有没有人有经验如何从中获得最佳性能？现在硬件加速似乎是可能的？
最好的问候和感谢所有输入。
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2 回答
2
flash.media.StageVideo是硬件加速播放减少CPU负载：
http://www.adobe.com/devnet/flashplayer/articles/stage_video.html
H.264 编解码器是舞台视频最好的朋友；使用这将确保您获得从视频解码到渲染的完整 GPU 加速。使用这种方法，不再需要回读（将数据从 GPU 发送到 CPU）来合成显示列表中的视频帧。YUV 4:2:0 格式的视频帧通过 GPU 着色器（DirectX9 或 OpenGL）转换为 RGB 并在屏幕上显示。因此，您将看到更高的像素保真度以及 CPU 和内存使用量的一些减少。
从上面的链接中，Thibault Imbert 有一个舞台视频的示例实现：
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();
}
}
}
于 2012-07-24T14:43:44.613 回答
1
要获得最佳视频，您需要使用新的StageVideo以使用硬件加速。该站点需要为 as3 并且 StageVideo 在正常的 flash 阶段下运行，因此您需要在视频播放时隐藏除控件之外的任何 flash 元素。此外，我会考虑使用 AIR 而不是投影仪方法将文件打包到一个独立的应用程序中。
于 2012-07-24T14:44:11.400 回答