streamconvert.php

<?php

/*
   This script, when installed on a webserver provides a means to convert
   ogg internet radio streams to mp3.
   
   One reason for doing a thing like this is hardware without ogg support,
   like my Sonos solution.

   This script depends on sox (http://sox.sourceforge.net) which must be
   compiled with ogg and mp3 write support (LAME).

   When installed, you can launch it either as

   http://yourserver/oggconvert.php?url=http://ormgas.rainwave.cc/ormgas.m3u

   to make the script output a m3u playlist pointing to itself or as

   http://yourserver/oggconvert.php?url=http://ormgas.rainwave.cc/ormgas.m3u&play=1
  
   to make the script start do the conversion.
   
   The script looks at the content-type returned from the server after fetching
   the document the url= parameter is pointing to. If it was a playlist, it
   will try to convert any stream pointed to by the playlist. If it was
   the ogg stream itself, it'll just convert that.

   In any other case, it bails out with an error message.
   
   In laymans terms this means that you can just put any URL remotely related
   to an ogg stream after the url= and the script will try to do the right thing.

   The script is (c) 2008 by Philip Hofstetter and licensed under the MIT license.
   Any questions can be directed to pilif@gnegg.ch
*/

// the path to the MP3-Write-Enabled SOX
define('SOX_PATH', '/opt/sox/bin/sox');

if (empty($_GET['url'])){
    die("no url to play provided. use ?url=url_of_stream to select the stream");
}
if ($_GET['play'] != '1'){
    header('Content-Type: audio/x-mpegurl');
    
    echo 'http://'.$_SERVER['HTTP_HOST'].$_SERVER['SCRIPT_NAME'].'?url='.rawurlencode($_GET['url'])."&play=1\n";
    exit;
}

$opts = array(
  'http'=>array(
    'method'=>"GET",
    'header'=>"User-Agent: ogg2mp3 (gnegg.ch/ogg2mp3)\r\n"
  )
);

$context = stream_context_create($opts);

$fh = fopen($_GET['url'], 'r', false, $context);
$header = array();
foreach($http_response_header as $line){
    list($name, $content) = explode(': ', $line, 2);
    $header[strtolower($name)] = $content;
}

switch($header['content-type']){
    case 'audio/x-mpegurl':
        $streams = fetchStreams($fh);
        fclose($fh);
        foreach($streams as $url) convertStreamUrl($url, $context);
        break;
    case 'application/ogg': 
        convertStream($fh);
        break;
    default: 
        header('Content-Type: text/plain');
        die("Server returned unknown Content-Type: ".$header['content-type']);
}

function fetchStreams($fh){
    $streams = array();
    while (!feof($fh)){
        $line = trim(fgets($fh));
        if (empty($line)) continue; // skip empty lines
        if (preg_match('%^\s*#%', $line)) continue; // skip comments
        $streams[] = $line;
    }
    return $streams;
}

function convertStreamUrl($url, $context){
    if ( ($fh = fopen(trim($url), 'r', false, $context)) === false) return false;
    convertStream($fh); // never returns
    return true;
}

function convertStream($fh){
    $descspec = array( 0 => array('pipe', 'r'),
                       1 => array('pipe', 'w'),
                       2 => array('file', '/tmp/oggerr.log', 'a')
                     );
    $pipes = array();
    $cmd = SOX_PATH.' -t ogg - -t mp3 -';
    $p = proc_open($cmd, $descspec, $pipes, '/tmp', $_ENV);
    if (!$p) die("cannot open sox\n");
    header('Content-Type: audio/mpeg');
    stream_set_blocking($pipes[1], 0);
    while (!feof($fh)){
        fwrite($pipes[0], fread($fh, 8192));
        echo fread($pipes[1], 8192);
    }
    fclose($pipes[0]);
    fclose($pipes[1]);
    proc_close($p);
    return true;
}
?>