title: Merge Multiple Videos using node fluent ffmpeg
body: <p>requirement is to read all the files in the directory and merge them.
          I am using node fluent-ffmpeg to achieve this.
          First of all reading all the files in the directory appending concatenating the string by adding <code>.input</code>.</p>
  
  <pre><code>var finalresult="E:/ETV/videos/finalresult.mp4"
  outputresult : It consists of all the files read in the directory.
  
  /*Javascript*/
  MergeVideo(outputresult);
  function MergeVideo(outputresult){
  console.log("in merge video");
  var videostring = "";
  
  for(i=1;i&lt;5;i++)
      {
  videostring = videostring+".input("+"'"+outputresult[i]+"'"+")";
  }
  console.log("Video String"+videostring);
      var proc = ffmpeg()+videostring
      .on('end', function() {
        console.log('files have  succesfully Merged');
          })
      .on('error', function(err) {
        console.log('an error happened: ' + err.message);
      })
      .mergeToFile(finalresult);
  }
  </code></pre>
  
  <p>It gives the following error:</p>
  
  <pre><code>TypeError: Object .input('ETV 22-02-2015 1-02-25 AM.mp4').input('ETV 22-02-2015
  9-33-15 PM.mp4').input('ETV 22-02-2015 9-32-46 AM.mp4').input('ETV 22-02-2015 8-
  32-44 AM.mp4') has no method 'on'
      at MergeVideo (D:\Development\Node\node-fluent-ffmpeg-master\node-fluent-ffm
  peg-master\examples\demo.js:140:6)
      at Object.&lt;anonymous&gt; (D:\Development\Node\node-fluent-ffmpeg-master\node-fl
  uent-ffmpeg-master\examples\demo.js:129:1)
      at Module._compile (module.js:456:26)
  </code></pre>
  
  <p>Any help is appreciated.</p>