flash actionscript 3.0 publish h264 stream

flash设置好gop，可以做到1秒之内的延迟，当然得配合支持关闭gop-cache的SRS服务器。例子参考高性能流媒体服务器SRS：https://github.com/winlinvip/simple-rtmp-server

SRS提供了视频会议和主播的flash例子源码，提供全js接口，详见：https://github.com/winlinvip/simple-rtmp-server/tree/master/trunk/research/players

NetStream.publish捕捉摄像头的图像，并编码后发送到FMS服务器。flash 11终于支持发布h264的流。因为推送h264的流，需要flash player能编码h264格式视频，在flash player 11加入了h264编码器。

官方参考：

http://help.adobe.com/en_US/FlashPlatform/reference/actionscript/3/flash/media/H264VideoStreamSettings.html

编写推送h164的as程序必须要较高版本的sdk，之前使用的flex sdk 4.1的flash player版本是10.0，不能用来编写这个程序。

下载flex sdk：

http://www.adobe.com/devnet/flex/flex-sdk-download.html

h264和h263对比图（同样的码率和分辨率）：

as3.0代码：

package
{
	import fl.controls.Button;
	import fl.controls.CheckBox;
	import fl.controls.ComboBox;
	import fl.controls.Label;
	import fl.controls.TextInput;
	
	import flash.display.Sprite;
	import flash.display.StageAlign;
	import flash.display.StageScaleMode;
	import flash.events.Event;
	import flash.events.MouseEvent;
	import flash.events.NetStatusEvent;
	import flash.media.Camera;
	import flash.media.H264Profile;
	import flash.media.H264VideoStreamSettings;
	import flash.media.Microphone;
	import flash.media.Video;
	import flash.net.NetConnection;
	import flash.net.NetStream;
	
	public class H264Publisher extends Sprite
	{	
		public function H264Publisher()
		{
			if(this.stage == null){
				this.addEventListener(Event.ADDED_TO_STAGE, this.onAddedToStage);
			}
			else{
				this.onAddedToStage(null);
			}
		}
		
		private function onAddedToStage(evt:Event):void{
			this.stage.align = StageAlign.TOP_LEFT;
			this.stage.scaleMode = StageScaleMode.NO_SCALE;
			
			var urlPanel:Sprite = new Sprite();
			this.addUrlPanel(urlPanel, onMouseClickStartPublish, onMouseClickStopPublish);
			
			var cameraPanel:Sprite = new Sprite();
			this.addCameraPanel(cameraPanel);
			
			var encodingPanel:Sprite = new Sprite();
			this.addEncodingPanel(encodingPanel);
			
			urlPanel.x = 10;
			urlPanel.y = 10;
			
			cameraPanel.x = urlPanel.x;
			cameraPanel.y = urlPanel.y + 30;
			
			encodingPanel.x = cameraPanel.x;
			encodingPanel.y = cameraPanel.y + 30;
			
			video = new Video();
			video.x = encodingPanel.x;
			video.y = encodingPanel.y + 30;
			
			this.addChild(urlPanel);
			this.addChild(cameraPanel);
			this.addChild(encodingPanel);
			this.addChild(video);
		}
		
		private var fmsUrl:String;
		private var fmsStream:String;
		private function discoveryFmsUrl():void{
			var url:String = txtUrl.text;
			
			if(url.toLowerCase().indexOf("rtmp://") < 0){
				trace("[error] the url must start with rtmp://", "error");
				return;
			}
			
			// remove the start rtmp://
			url = url.substr(url.toLowerCase().indexOf("rtmp://") + "rtmp://".length);
			
			var server:String = url.substr(0, url.indexOf("/"));
			url = url.substr(url.indexOf("/") + 1);
			
			var port:String = "1935";
			if(server.indexOf(":") >= 0){
				port = server.substr(server.indexOf(":")+1);
				server = server.substr(0, server.indexOf(":"));
			}
			
			var appIndex:int = -1;
			for(var i:int = 0; i < this.cbAppLevel.selectedIndex + 1; i++){
				if(url.indexOf("/", appIndex + 1) < 0){
					break;
				}
				
				appIndex = url.indexOf("/", appIndex + 1);
			}
			var app:String = url.substr(0, appIndex);
			var stream:String = url.substr(appIndex + 1);
			
			// if user input ip address, set the server; otherwise, set the vhost.
			var serverIsIPAddress:Boolean = true;
			var serverItems:Array = server.split(".");
			for(i = 0; i < serverItems.length; i++){
				if(isNaN(Number(serverItems[i]))){
					serverIsIPAddress = false;
				}
			}
			
			fmsUrl = "rtmp://" + server + ":" + port + "/" + app;
			fmsStream = stream;
		}
		
		private function buildEncodingParameters(publishStream:NetStream, c:Camera, m:Microphone):void{
			var x264profile:String = (this.cbX264Profile.selectedLabel == "Main") ? H264Profile.MAIN : H264Profile.BASELINE;
			var x264level:String = this.cbX264Level.selectedLabel;
			var x264KeyFrameInterval:int = int(this.cbX264KeyFrameInterval.selectedIndex + 1);
			var cameraWidth:int = int(this.cbCameraSize.selectedLabel.substr(0, this.cbCameraSize.selectedLabel.indexOf("x")));
			var cameraHeight:int = int(this.cbCameraSize.selectedLabel.substr(this.cbCameraSize.selectedLabel.indexOf("x") + 1));;
			var cameraFps:Number = Number(this.cbCameraFps.selectedLabel);
			var cameraBitrate:int = int(this.cbCameraBitrate.selectedLabel);
			var cameraQuality:int = 85;
			var microEncodeQuality:int = 8;
			var microRate:int = 22; // 22 === 22050 Hz
			
			trace("[Publish] h.264(x264) encoding parameters: " 
				+ "profile=" + x264profile 
				+ ", level=" + x264level
				+ ", keyFrameInterval(gop)=" + x264KeyFrameInterval
				+ "; video(camera) width=" + cameraWidth
				+ ", height=" + cameraHeight
				+ ", fps=" + cameraFps
				+ ", bitrate=" + cameraBitrate
				+ ", quality=" + cameraQuality
				+ "; audio(microphone) encodeQuality=" + microEncodeQuality
				+ ", rate=" + microRate + "(22050Hz)"
			);
			
			var h264Settings:H264VideoStreamSettings = new H264VideoStreamSettings();
			// we MUST set its values first, then set the NetStream.videoStreamSettings, or it will keep the origin values.
			h264Settings.setProfileLevel(x264profile, x264level); 
			publishStream.videoStreamSettings = h264Settings;
			// the setKeyFrameInterval/setMode/setQuality use the camera settings.
			// http://help.adobe.com/en_US/FlashPlatform/reference/actionscript/3/flash/media/VideoStreamSettings.html
			// Note This feature will be supported in future releases of Flash Player and AIR, for now, Camera parameters are used.
			/*h264Settings.setKeyFrameInterval(4);
			h264Settings.setMode(800, 600, 15);
			h264Settings.setQuality(500, 0);*/
			
			// set the camera and microphone.
			
			// setKeyFrameInterval(keyFrameInterval:int):void
			// 	keyFrameInterval:int — A value that specifies which video frames are transmitted in full (as keyframes) instead of being 
			//		interpolated by the video compression algorithm. A value of 1 means that every frame is a keyframe, a value of 3 means 
			//		that every third frame is a keyframe, and so on. Acceptable values are 1 through 48.
			c.setKeyFrameInterval(x264KeyFrameInterval);
			
			// setMode(width:int, height:int, fps:Number, favorArea:Boolean = true):void
			//  width:int — The requested capture width, in pixels. The default value is 160.
			//  height:int — The requested capture height, in pixels. The default value is 120.
			//  fps:Number — The requested rate at which the camera should capture data, in frames per second. The default value is 15.
			c.setMode(cameraWidth, cameraHeight, cameraFps);
			
			// setQuality(bandwidth:int, quality:int):void
			//  bandwidth:int — Specifies the maximum amount of bandwidth that the current outgoing video feed can use, in bytes per second. 
			//		To specify that the video can use as much bandwidth as needed to maintain the value of quality, pass 0 for bandwidth. 
			//		The default value is 16384.
			//  quality:int — An integer that specifies the required level of picture quality, as determined by the amount of compression 
			// 		being applied to each video frame. Acceptable values range from 1 (lowest quality, maximum compression) to 100 
			//		(highest quality, no compression). To specify that picture quality can vary as needed to avoid exceeding bandwidth, 
			//		pass 0 for quality.
			//  winlin:
			//		bandwidth is in bps not kbps. 500*1000 = 500kbps.
			//		quality=1 is lowest quality, 100 is highest quality.
			c.setQuality(cameraBitrate * 1000, cameraQuality);
			
			// if no microphone, donot set the params.
			if(m == null){
				return;
			}
			
			// The encoded speech quality when using the Speex codec. Possible values are from 0 to 10. The default value is 6. Higher numbers 
			// represent higher quality but require more bandwidth, as shown in the following table. The bit rate values that are listed represent 
			// net bit rates and do not include packetization overhead.
			m.encodeQuality = microEncodeQuality;
			
			// The rate at which the microphone is capturing sound, in kHz. Acceptable values are 5, 8, 11, 22, and 44. The default value is 8 kHz 
			// if your sound capture device supports this value. Otherwise, the default value is the next available capture level above 8 kHz that 
			// your sound capture device supports, usually 11 kHz.
			m.rate = microRate;
		}
		
		private var publishStream:NetStream;
		private var publishConnection:NetConnection;
		private function onMouseClickStartPublish(evt:MouseEvent):void{
			// if published, donothing
			if(publishStream != null){
				return;
			}
			
			this.btnStartPublish.enabled = false;
			this.btnStopPublish.enabled = true;
			
			this.discoveryFmsUrl();
			
			publishConnection = new NetConnection();
			var conn:NetConnection = publishConnection;
			
			conn.client = {};
			conn.client.onBWDone = function():void{};
			
			conn.addEventListener(NetStatusEvent.NET_STATUS, function(evt:NetStatusEvent):void{
				trace("[Publish][connection] code:" + evt.info.code);
				
				switch(evt.info.code){
					case "NetConnection.Connect.Success":
						publishStream = new NetStream(conn);
						// microphone and camera
						var m:Microphone = Microphone.getMicrophone(cbMicrophone.selectedIndex);
						// Remark: the name is the index!
						var c:Camera = Camera.getCamera(String(cbCamera.selectedIndex));
						if(c == null){
							trace("[Publish][error] failed to open camera(name=" + String(cbCamera.selectedIndex) + "): " + cbCamera.selectedLabel, "error");
							cleanupPublishedStream();
							break;
						}
						else if(c.muted){
							trace("[Publish][error] open camera(name=" + String(cbCamera.selectedIndex) + ") failed, it's muted: " + cbCamera.selectedLabel, "error");
							cleanupPublishedStream();
							break;
						}
						
						buildEncodingParameters(publishStream, c, m);
						
						publishStream.addEventListener(NetStatusEvent.NET_STATUS, function(evt:NetStatusEvent):void{
							trace("[Publish][NetStreamStatus]" + evt.info.code);
							
							switch(evt.info.code){
								case "NetStream.Publish.Start":
									var h264:H264VideoStreamSettings = publishStream.videoStreamSettings as H264VideoStreamSettings;
									trace("[Publish] video codec: " + h264.codec 
										+ ", profile=" + h264.profile
										+ ", level=" + h264.level
										+ ", quality=" + h264.quality
										+ ", fps=" + h264.fps
										+ ", gop=" + h264.keyFrameInterval
										+ ", bandwidth=" + h264.bandwidth
										+ ", size=" + h264.width + "x" + h264.height);
									break;
								case "NetStream.Publish.BadName":
									cleanupPublishedStream();
									break;
							}
						});
						publishStream.publish(fmsStream);
						
						// attach video and audio.
						trace("[Publish][debug] start publish, using camera(name=" + String(cbCamera.selectedIndex) + "): " + c.name);
						publishStream.attachCamera(c);
						if(m != null && !m.muted){
							trace("[Publish][debug] start publish, using microphone(name=" + String(cbMicrophone.selectedIndex) + "): " + m.name);
							publishStream.attachAudio(m);
						}
						restartPlayback();
						break;
					case "NetConnection.Connect.Rejected":
					case "NetConnection.Connect.Failed":
						cleanupPublishedStream();
						break;
				}
			});
			
			conn.connect(fmsUrl);
		}
		private function cleanupPublishedStream():void{
			this.btnStartPublish.enabled = true;
			this.btnStopPublish.enabled = false;
			if(this.publishStream != null){
				this.publishStream.close();
			}
			if(this.publishConnection != null){
				this.publishConnection.close();
			}
			this.publishStream = null;
		}
		
		public var stream:NetStream;
		private var conn:NetConnection;
		private var video:Video;
		private function restartPlayback():void{
			// stream is playing, resume it.
			if(this.stream != null){
				this.stream.close();
			}
			
			conn = new NetConnection();
			
			conn.client = {};
			conn.client.onBWDone = function():void{};
			conn.addEventListener(NetStatusEvent.NET_STATUS, function(evt:NetStatusEvent):void{
				trace("[connection] code:" + evt.info.code + " desc:" + evt.info.description);
				
				switch(evt.info.code){
					case "NetConnection.Connect.Success":
						stream = new NetStream(conn);
						video.attachNetStream(stream);
						
						//stream.bufferTime = 3;
						stream.addEventListener(NetStatusEvent.NET_STATUS, function(evt:NetStatusEvent):void{
							trace("[NetStreamStatus]" + evt.info.code + " desc:" + evt.info.description);
						});
						stream.client = {};
						stream.client.onMetaData = function onMetadata(metadata:Object):void{
							var o:Object = {};
							for(var key:String in metadata){
								o[key] = metadata[key];
								trace("[metadata] " + "key=" + key + ", value=" + o[key]);
							}
							
							if(metadata.width == undefined){
								metadata.width = 10;
								trace("[warning] metadata.width is undefied, set to 10");
							}
							if(metadata.height == undefined){
								metadata.height = 10;
								trace("[warning] metadata.height is undefied, set to 10");
							}
							
							video.width = metadata.width;
							video.height = metadata.height;
						};
						
						if(!cbIsLive.selected){
							stream.play(fmsStream, 0);
						}
						else{
							stream.play(fmsStream);
						}
						break;
					case "NetConnection.Connect.Rejected":
					case "NetConnection.Connect.Failed":
						stream.close();
						stream = null;
						break;
				}
			});
			conn.connect(fmsUrl);
		}
		
		private function onMouseClickStopPublish(evt:MouseEvent):void{
			this.cleanupPublishedStream();
		}
		
		private var txtUrl:TextInput;
		private var btnStartPublish:Button;
		private var btnStopPublish:Button;
		private var cbAppLevel:ComboBox;
		private var cbIsLive:CheckBox;
		private function addUrlPanel(
			panel:Sprite, 
			onMouseClickStartPublish:Function, onMouseClickStopPublish:Function
		):void{
			var lblUrl:Label = new Label();
			lblUrl.text = "RTMP Url:";
			lblUrl.width = 50;
			panel.addChild(lblUrl);
			
			txtUrl = new TextInput();
			txtUrl.width = 380;
			txtUrl.x = lblUrl.x + lblUrl.width + 3;
			panel.addChild(txtUrl);
			
			cbIsLive = new CheckBox();
			cbIsLive.selected = true;
			cbIsLive.label = "Live";
			cbIsLive.width = 53;
			cbIsLive.x = txtUrl.x + txtUrl.width + 0;
			panel.addChild(cbIsLive);
			
			cbAppLevel = new ComboBox();
			cbAppLevel.addItem({label: "1级App"});
			cbAppLevel.addItem({label: "2级App"});
			cbAppLevel.addItem({label: "3级App"});
			cbAppLevel.addItem({label: "4级App"});
			cbAppLevel.width = 70;
			cbAppLevel.x = cbIsLive.x + cbIsLive.width + 0;
			panel.addChild(cbAppLevel);
			
			btnStartPublish = new Button();
			btnStartPublish.label = "发布流";
			btnStartPublish.width = 60;
			btnStartPublish.x = cbAppLevel.x + cbAppLevel.width + 3;
			btnStartPublish.addEventListener(MouseEvent.CLICK, onMouseClickStartPublish);
			panel.addChild(btnStartPublish);
			
			btnStopPublish = new Button();
			btnStopPublish.label = "停止发布";
			btnStopPublish.width = 60;
			btnStopPublish.enabled = false;
			btnStopPublish.x = btnStartPublish.x + btnStartPublish.width + 3;
			btnStopPublish.addEventListener(MouseEvent.CLICK, onMouseClickStopPublish);
			panel.addChild(btnStopPublish);
		}
		
		private var cbX264Profile:ComboBox;
		private var cbX264Level:ComboBox;
		private var cbX264KeyFrameInterval:ComboBox;
		private var cbCameraSize:ComboBox;
		private var cbCameraFps:ComboBox;
		private var cbCameraBitrate:ComboBox;
		private function addEncodingPanel(
			panel:Sprite
		):void{
			var lblX264Profile:Label = new Label();
			lblX264Profile.text = "Profile:";
			lblX264Profile.width = 38;
			lblX264Profile.y = 2;
			panel.addChild(lblX264Profile);
			
			cbX264Profile = new ComboBox();
			cbX264Profile.width = 72;
			cbX264Profile.x = lblX264Profile.x + lblX264Profile.width + 0;
			panel.addChild(cbX264Profile);
			cbX264Profile.addItem({label:"Baseline"});
			cbX264Profile.addItem({label:"Main"});
			
			var lblX264Level:Label = new Label();
			lblX264Level.text = "Level:";
			lblX264Level.width = 32;
			lblX264Level.y = 2;
			lblX264Level.x = cbX264Profile.x + cbX264Profile.width + 1;
			panel.addChild(lblX264Level);
			
			cbX264Level = new ComboBox();
			cbX264Level.width = 45;
			cbX264Level.x = lblX264Level.x + lblX264Level.width + 1;
			panel.addChild(cbX264Level);
			var x264Levels:Array = ["1", "1b", "1.1", "1.2", "1.3", "2", "2.1", "2.2", "3", "3.1", "3.2", "4", "4.1", "4.2", "5", "5.1"];
			for(var i:int = 0; i < x264Levels.length; i++){
				cbX264Level.addItem({label:x264Levels[i]});
			}
			cbX264Level.selectedIndex = 8;
			
			var lblX264KeyFrameInterval:Label = new Label();
			lblX264KeyFrameInterval.text = "GOP:";
			lblX264KeyFrameInterval.width = 29;
			lblX264KeyFrameInterval.y = 2;
			lblX264KeyFrameInterval.x = cbX264Level.x + cbX264Level.width + 1;
			panel.addChild(lblX264KeyFrameInterval);
			
			cbX264KeyFrameInterval = new ComboBox();
			cbX264KeyFrameInterval.width = 87;
			cbX264KeyFrameInterval.x = lblX264KeyFrameInterval.x + lblX264KeyFrameInterval.width + 1;
			panel.addChild(cbX264KeyFrameInterval);
			for(i = 0; i < 48; i++){
				cbX264KeyFrameInterval.addItem({label:String(i + 1) + " seconds"});
			}
			cbX264KeyFrameInterval.selectedIndex = 3;
			
			var lblCameraSize:Label = new Label();
			lblCameraSize.text = "Size:";
			lblCameraSize.width = 30;
			lblCameraSize.y = 2;
			lblCameraSize.x = cbX264KeyFrameInterval.x + cbX264KeyFrameInterval.width + 1;
			panel.addChild(lblCameraSize);
			
			cbCameraSize = new ComboBox();
			cbCameraSize.width = 82;
			cbCameraSize.x = lblCameraSize.x + lblCameraSize.width + 1;
			panel.addChild(cbCameraSize);
			var sizes:Array = ["176x144", "320x240", "352x240", "352x288", "640x480", "720x480", "720x576", "800x600", "1024x768", "1280x720", "1360x768", "1920x1080"];
			for(i = 0; i < sizes.length; i++){
				cbCameraSize.addItem({label:sizes[i]});
			}
			cbCameraSize.selectedIndex = 1;
			
			var lblCameraFps:Label = new Label();
			lblCameraFps.text = "FPS:";
			lblCameraFps.width = 28;
			lblCameraFps.y = 2;
			lblCameraFps.x = cbCameraSize.x + cbCameraSize.width + 1;
			panel.addChild(lblCameraFps);
			
			cbCameraFps = new ComboBox();
			cbCameraFps.width = 58;
			cbCameraFps.x = lblCameraFps.x + lblCameraFps.width + 1;
			panel.addChild(cbCameraFps);
			var fpses:Array = ["1.00", "4.00", "5.00", "6.00", "8.00", "10.00", "12.00", "14.98", "15.00", "20.00", "24.00", "25.00", "29.97", "30.00", "59.94", "60.00"];
			for(i = 0; i < fpses.length; i++){
				cbCameraFps.addItem({label:fpses[i]});
			}
			cbCameraFps.selectedIndex = 8;
			
			var lblCameraBitrate:Label = new Label();
			lblCameraBitrate.text = "Bitrate:";
			lblCameraBitrate.width = 40;
			lblCameraBitrate.y = 2;
			lblCameraBitrate.x = cbCameraFps.x + cbCameraFps.width + 1;
			panel.addChild(lblCameraBitrate);
			
			cbCameraBitrate = new ComboBox();
			cbCameraBitrate.width = 58;
			cbCameraBitrate.x = lblCameraBitrate.x + lblCameraBitrate.width + 1;
			panel.addChild(cbCameraBitrate);
			var bitrates:Array = ["10", "50", "100", "200", "350", "500", "650", "800", "950", "1000", "1200", "1500", "1800", "2000", "2500", "20000"];
			for(i = 0; i < bitrates.length; i++){
				cbCameraBitrate.addItem({label:bitrates[i]});
			}
			cbCameraBitrate.selectedIndex = 3;
		}
		
		private var cbCamera:ComboBox;
		private var cbMicrophone:ComboBox;
		private function addCameraPanel(
			panel:Sprite
		):void{
			// camera
			var lblCamera:Label = new Label();
			lblCamera.text = "Available Cameras:";
			lblCamera.width = 100;
			panel.addChild(lblCamera);
			
			cbCamera = new ComboBox();
			cbCamera.width = 160;
			cbCamera.x = lblCamera.x + lblCamera.width + 3;
			panel.addChild(cbCamera);
			
			var cameras:Array = Camera.names;
			for(var i:int = 0; i < cameras.length; i++){
				cbCamera.addItem({label:cameras[i]});
			}
			
			// microphone
			var lblMicrophone:Label = new Label();
			lblMicrophone.text = "Available Microphones:";
			lblMicrophone.width = 120;
			lblMicrophone.x = cbCamera.x + cbCamera.width + 10;
			panel.addChild(lblMicrophone);
			
			cbMicrophone = new ComboBox();
			cbMicrophone.width = 180;
			cbMicrophone.x = lblMicrophone.x + lblMicrophone.width + 3;
			panel.addChild(cbMicrophone);
			
			var microphones:Array = Microphone.names;
			for(i = 0; i < microphones.length; i++){
				cbMicrophone.addItem({label:microphones[i]});
			}
		}
	}
}

其中用到了FlashCS5的控件，可以将c:\Program Files (x86)\Adobe\Adobe Flash CS5\Common\Configuration\Components\User Interface.fla打开后导出swc，然后在actionscript3项目中引用这个swc就可以了。