transcoding

README.md

@@ -17,13 +17,12 @@ Coming soon (maybe):
 
     npm install transcode
     node
-    > var transcoder = require('transcode').createTranscoder(
-        'input.flv',
-        'output.mp4', {
-          preset: 'appletv'
-        }).start(function(err, result) {
-          // Done!
-        });
+    > var transcode = require('transcode');
+    > var transcoder = transcode.createTranscoder('input.flv');
+    > transcoder.setProfile(transcode.profiles.APPLE_TV);
+    > transcoder.writeToFile('output.m4v', function(err, result) {
+        // Done!
+      });
 
 ## Installation
 

examples/transcode.js

@@ -0,0 +1,22 @@
+#!/usr/bin/env node
+
+var transcode = require('transcode');
+var util = require('util');
+
+var paths = process.argv.slice(2);
+if (!paths.length) {
+  util.puts('no input files');
+  return;
+}
+if (paths.length < 2) {
+  util.puts('no output file');
+  return;
+}
+var outputPath = paths.pop();
+
+var transcoder = transcode.createTranscoder(paths);
+transcoder.setProfile(transcode.profiles.APPLE_TV);
+transcoder.writeToFile(outputPath, function(err) {
+  util.puts('complete!');
+  process.exit();
+});

lib/transcode.js

@@ -1,7 +1,10 @@
 var ffmpeg = require('./transcode/ffmpeg');
+var profiles = require('./transcode/profiles');
 
 var ffmpegInfo = ffmpeg.detect();
 
+exports.profiles = profiles;
+
 exports.verifyConfiguration = function(callback) {
   var err = null;
   if (!ffmpegInfo) {
@@ -16,8 +19,8 @@ exports.verifyConfiguration = function(callback) {
 };
 
 exports.Transcoder = require('./transcode/transcoder').Transcoder;
-exports.createTranscoder = function() {
-  return new exports.Transcoder(ffmpegInfo);
+exports.createTranscoder = function(inputs) {
+  return new exports.Transcoder(ffmpegInfo, inputs);
 };
 
 var queryInfo = require('./transcode/mediainfo').queryInfo;

lib/transcode/ffmpeg.js

@@ -13,16 +13,41 @@ exports.detect = function() {
 var Ffmpeg = function(info) {
   this.info_ = info;
 
+  this.priority_ = 0;
   this.inputs_ = [];
+  this.output_ = null;
+  this.options_ = {
+  };
 };
 exports.Ffmpeg = Ffmpeg;
 
+Ffmpeg.prototype.setPriority = function(priority) {
+  this.priority_ = priority;
+  return this;
+};
+
 Ffmpeg.prototype.addInput = function(streamOrPath) {
   this.inputs_.push(streamOrPath);
+  return this;
 };
 
 Ffmpeg.prototype.addInputs = function(inputs) {
-  this.inputs_ = this.inputs_.concat(inputs);
+  if (util.isArray(inputs)) {
+    this.inputs_ = this.inputs_.concat(inputs);
+  } else {
+    this.inputs_.push(inputs);
+  }
+  return this;
+};
+
+Ffmpeg.prototype.setOutput = function(streamOrPath) {
+  this.output_ = streamOrPath;
+  return this;
+};
+
+Ffmpeg.prototype.setOptions = function(options) {
+  this.options_ = options;
+  return this;
 };
 
 Ffmpeg.prototype.exec = function() {
@@ -49,17 +74,48 @@ Ffmpeg.prototype.exec = function() {
     }
   }
 
-  // Build args
   var args = [];
+
+  // Basics
+  args.push('-y'); // always overwrite output files
+
+  // Input args
   if (inputStream) {
-    args.push('-i');
-    args.push('-');
+    args.push('-i', '-');
   }
   for (var n = 0; n < inputPaths.length; n++) {
     var inputPath = path.normalize(inputPaths[n]);
-    args.push('-i');
-    args.push(inputPath);
+    args.push('-i', inputPath);
+  }
+
+  // Real options
+  // TODO: options
+  args.push('-vcodec', 'copy');
+  args.push('-acodec', 'copy');
+
+  // Output
+  if (this.output_) {
+    if (typeof this.output_ == 'string') {
+      args.push(this.output_);
+    } else {
+      args.push('pipe:1');
+    }
+  }
+
+  // Spawn the process and wire up input (if required)
+  util.puts('calling ffmpeg:');
+  util.puts('  ' + args.join(' '));
+  var proc = child_process.spawn(this.info_.path, args);
+  if (inputStream) {
+    inputStream.resume();
+    inputStream.pipe(proc.stdin);
+  }
+
+  // renice to a lower priority
+  if (this.priority_ !== null) {
+    child_process.exec('renice -p ' + proc.pid + ' -n ' +
+        (this.priority_ ? '+' + this.priority_ : this.priority_));
   }
 
-  return child_process.spawn(this.info_.path, args);
+  return proc;
 };

lib/transcode/profiles.js

@@ -0,0 +1,3 @@
+exports.APPLE_TV = {
+
+};

lib/transcode/transcoder.js

@@ -2,26 +2,56 @@ var events = require('events');
 var fs = require('fs');
 var util = require('util');
 
-var Transcoder = function(ffmpegInfo) {
+var queryInfo = require('./mediainfo').queryInfo;
+var Ffmpeg = require('./ffmpeg').Ffmpeg;
+
+var Transcoder = function(ffmpegInfo, inputs) {
   this.ffmpegInfo_ = ffmpegInfo;
+
+  this.ffmpeg_ = new Ffmpeg(ffmpegInfo);
+  if (inputs) {
+    this.ffmpeg_.addInputs(inputs);
+  }
+
+  this.profile_ = null;
 };
 util.inherits(Transcoder, events.EventEmitter);
 exports.Transcoder = Transcoder;
 
+Transcoder.prototype.setProfile = function(profile) {
+  this.profile_ = profile;
+};
+
 Transcoder.prototype.attachInputStream = function(stream) {
-  //
+  this.ffmpeg_.addInput(stream);
 };
 
 Transcoder.prototype.attachInputFile = function(path) {
-  var stream = fs.createReadStream(path);
-  this.attachInputStream(stream);
+  this.ffmpeg_.addInput(path);
 };
 
 Transcoder.prototype.writeToStream = function(stream, callback) {
-  //
+  this.ffmpeg_.setOutput(stream);
+  this.write_(callback);
 };
 
 Transcoder.prototype.writeToFile = function(path, callback) {
-  var stream = fs.createWriteStream(path);
-  this.writeToStream(stream, callback);
+  this.ffmpeg_.setOutput(path);
+  this.write_(callback);
+};
+
+Transcoder.prototype.write_ = function(callback) {
+  // TODO: set options from profile
+
+  var proc = this.ffmpeg_.exec();
+
+  // proc.stderr.on('data', function(data) {
+  //   util.puts('stderr: ' + data);
+  // });
+
+  proc.on('exit', function(code) {
+    if (callback) {
+      callback(null);
+    }
+  });
 };