Tune ffmpeg command to start playback and transcode faster

Add option for custom flags

docs/CONFIGURATION.md

@@ -26,6 +26,15 @@ transcode:
 # satyr will generate one source quality variant, and the remaining
 # variants will be of incrementally lower quality and bitrate
 
+  inputflags: ""
+# additional flags to apply to the input during transcoding
+  outputflags: ""
+# additional flags to apply to the output during transcoding
+
+# hardware acceleration is a bit difficult to configure programmatically
+# this is a good place to do so for your system
+# https://trac.ffmpeg.org/wiki/HWAccelIntro is a good place to start
+
 # having more than 4-5 variants will start giving diminishing returns on stream quality for cpu load
 # if you can't afford to generate at least 3 variants, it's reccomended to leave adaptive streaming off
 

src/config.ts

@@ -46,7 +46,9 @@ const config: Object = {
 	transcode: Object.assign({ 
 		adapative: false, 
 		variants: 3, 
-		format: 'dash' 
+		format: 'dash',
+		inputflags: null,
+		outputflags: null
 	}, localconfig['transcode']),
 	chat: {
 		irc: Object.assign({

src/server.ts

@@ -41,7 +41,11 @@ function init () {
 				while(true){
 					if(session.audioCodec !== 0 && session.videoCodec !== 0){
 						transCommand(results[0].username, key).then((r) => {
-							execFile(config['media']['ffmpeg'], r, {maxBuffer: Infinity}, (err, stdout, stderr) => {});
+							execFile(config['media']['ffmpeg'], r, {maxBuffer: Infinity}, (err, stdout, stderr) => {
+								console.log(err);
+								console.log(stdout);
+								console.log(stderr);
+							});
 						});
 						break;
 					}
@@ -112,7 +116,9 @@ function init () {
 }
 
 async function transCommand(user: string, key: string): Promise<string[]>{
-	let args: string[] = [/*'-loglevel', 'fatal',*/ '-y', '-i', 'rtmp://127.0.0.1:'+config['rtmp']['port']+'/'+config['media']['privateEndpoint']+'/'+key];
+	let args: string[] = ['-loglevel', 'fatal', '-y'];
+	if(config['transcode']['inputflags'] !== null && config['transcode']['inputflags'] !== "") args = args.concat(config['transcode']['inputflags'].split(" "));
+	args = args.concat(['-i', 'rtmp://127.0.0.1:'+config['rtmp']['port']+'/'+config['media']['privateEndpoint']+'/'+key, '-movflags', '+faststart']);
 	if(config['transcode']['adaptive']===true && config['transcode']['variants'] > 1) {
 		for(let i=0;i<config['transcode']['variants'];i++){
 			args = args.concat(['-map', '0:2']);
@@ -133,8 +139,11 @@ async function transCommand(user: string, key: string): Promise<string[]>{
 	else {
 		args = args.concat(['-c:a', 'aac', '-c:v', 'libx264']);
 	}
+	args = args.concat(['-preset', 'veryfast', '-tune', 'zerolatency']);
 	//if(config['transcode']['format'] === 'dash')
-	args = args.concat(['-remove_at_exit', '1', '-seg_duration', '1', '-window_size', '30', '-f', 'dash', config['http']['directory']+'/'+config['media']['publicEndpoint']+'/'+user+'/index.mpd']);
+	args = args.concat(['-remove_at_exit', '1', '-seg_duration', '1', '-window_size', '30']);
+	if(config['transcode']['outputflags'] !== null && config['transcode']['outputflags'] !== "") args = args.concat(config['transcode']['outputflags'].split(" "));
+	args = args.concat(['-f', 'dash', config['http']['directory']+'/'+config['media']['publicEndpoint']+'/'+user+'/index.mpd']);
 	//else if(config['transcode']['format'] === 'hls')
 	//args = args.concat(['-remove_at_exit', '1', '-hls_time', '1', '-hls_list_size', '30', '-f', 'hls', config['http']['directory']+'/'+config['media']['publicEndpoint']+'/'+user+'/index.m3u8']);
 	return args;