how to convert speech to text with gogle api

<?php

 

// Convert Words (text) to Speech (MP3)

// ------------------------------------

 

// Google Translate API cannot handle strings > 100 characters

   $words = substr($_GET['words'], 0, 100);

 

// Replace the non-alphanumeric characters

// The spaces in the sentence are replaced with the Plus symbol

   $words = urlencode($_GET['words']);

 

// Name of the MP3 file generated using the MD5 hash

   $file  = md5($words);

  

// Save the MP3 file in this folder with the .mp3 extension

   $file = "audio/" . $file . ".mp3";

 

// If the MP3 file exists, do not create a new request

   if (!file_exists($file)) {

     $mp3 = file_get_contents(

        'http://translate.google.com/translate_tts?q=' . $words;

     file_put_contents($file, $mp3);

   }

?>

 

// Embed the MP3 file using the AUDIO tag of HTML5

<audio controls="controls" autoplay="autoplay">

  <source src="<? echo $file; ?>" type="audio/mp3" />

</audio>