code: function( shotBuffer ) {
  
          var scope = this;
  
          var image = "data:image/"
              + scope.opts.output
              + ";base64,"
              + new Buffer( shotBuffer ).toString( "base64" );
  
          return image;
  
      }
docs: Get base64 string from bufer
  
  @method getBase64
  
  @param {Number|FS.readFile} shot To be converted
  @param {Function( Error|null, Mixed )} callback Returns base64 string
  
  @return {String} Dont use