Using Google Text to Speech API – PHP

Google offers an undocumented text to speech API that help you transform text into voice. You can see a live demo at ctrlq.org/listen.

The following snippet of PHP code is responsible for the conversion while the MP3 files are cached to reduce requests to Google Translation servers.

<?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>

Google Text to Speech – Command Line

You can also convert any piece of text to MP3 files from the command line using the wget or CURL command. Remember that the value of “q” parameter should have less than 100 characters else the Google Translate TTS API will throw an error.

wget -q -U Mozilla -O audio.mp3 "http://translate.google.com/translate_tts?ie=UTF-8&tl=en&q=hello+world

curl -A "Mozilla" "http://translate.google.com/translate_tts?tl=en&q=hello+world" > audio.mp3