<?php
class mp3

    {
    var $str;
    var $time;
    var $frames;

    // Create a new mp3

    function mp3($path = "")
        {
        if ($path != "")
            {
            $this->str = file_get_contents($path);
            }
        }

    // Put an mp3 behind the first mp3

    function mergeBehind($mp3)
        {
        $this->str.= $mp3->str;
        }

    // Calculate where's the end of the sound file

    function getIdvEnd()
        {
        $strlen = strlen($this->str);
        $str = substr($this->str, ($strlen - 128));
        $str1 = substr($str, 0, 3);
        if (strtolower($str1) == strtolower('TAG'))
            {
            return $str;
            }
          else
            {
            return false;
            }
        }

    // Calculate where's the beginning of the sound file

    function getStart()
        {
        $strlen = strlen($this->str);
        for ($i = 0; $i < $strlen; $i++)
            {
            $v = substr($this->str, $i, 1);
            $value = ord($v);
            if ($value == 255)
                {
                return $i;
                }
            }
        }

    // Remove the ID3 tags

    function striptags()
        {

        // Remove start stuff...

        $newStr = '';
        $s = $start = $this->getStart();
        if ($s === false)
            {
            return false;
            }
          else
            {
            $this->str = substr($this->str, $start);
            }

        // Remove end tag stuff

        $end = $this->getIdvEnd();
        if ($end !== false)
            {
            $this->str = substr($this->str, 0, (strlen($this->str) - 129));
            }
        }

    // Display an error

    function error($msg)
        {

        // Fatal error

        die('<strong>audio file error: </strong>' . $msg);
        }

    // Send the new mp3 to the browser

    function output($path)
        {

        // Output mp3
        // Send to standard output

        if (ob_get_contents()) $this->error('Some data has already been output, can\'t send mp3 file');
        if (php_sapi_name() != 'cli')
            {

            // We send to a browser

            header('Content-Type: audio/mpeg3');
            if (headers_sent()) $this->error('Some data has already been output to browser, can\'t send mp3 file');
            header('Content-Length: ' . strlen($this->str));
            header('Content-Disposition: attachment; filename="' . $path . '"');
            }

        echo $this->str;
        return '';
        }
    }

// First File: (Google speech)

$mp3 = new mp3('1.mp3');
$mp3->striptags();

// Second file

$second = new mp3("2.mp3");
$mp3->mergeBehind($second);
$mp3->striptags();
$mp3->output('word.mp3'); //Output file (current a blank file)