Can't extract metdata from some icecast streams - php

Question

I'm trying to extract icecast metadata from streams.
I have code that works for some streams and not for others.
The issue is that some streams don't return the icymetaint value and that's where the code gets lost.
I can't get the icymetaint header from this stream:
http://radio.hbr1.com:19800/tronic.ogg
But when I put it in VLC media player it shows the meta just fine.
So what exactly am I missing here? What other ways are there for an icecast stream to transmit metdata? The stream version is Icecast 2.3.3
This is code inside a class to retrieve the metadata and headers:
public function GetDataFromStream($parsedUrl)
{
$returnData = array();
$addr = $parsedUrl['host'];
$addr = gethostbyname($addr);
$sock = fsockopen($addr, $parsedUrl['port'], $errno, $errstr, 5);
$path = isset($parsedUrl['path'])?$parsedUrl['path']:'/';
if ($sock)
{
$request = 'GET '. $path .' HTTP/1.0' . CRLF .
'Host: ' . $parsedUrl['host'] . CRLF .
'Connection: Close' . CRLF .
'User-Agent: ' . $this->useragent . CRLF .
'Accept: */*' . CRLF .
'icy-metadata: 1'.CRLF.
'icy-prebuffer: 65536'.CRLF.
(isset($parsedUrl['user']) ? 'Authorization: Basic ' .
base64_encode($parsedUrl['user'] . ':' . $parsedUrl['pass']) . CRLF : '').
'X-TipOfTheDay: Winamp "Classic" rulez all of them.' . CRLF . CRLF;
if (fwrite($sock, $request))
{
$theaders = $line = '';
while (!feof($sock))
{
$line = fgets($sock, 4096);
if('' == trim($line))
break;
$theaders .= $line;
}
$theaders = explode(CRLF, $theaders);
foreach ($theaders as $header)
{
$t = explode(':', $header);
if (isset($t[0]) && trim($t[0]) != '')
{
$name = preg_replace('/[^a-z][^a-z0-9]*/i','', strtolower(trim($t[0])));
array_shift($t);
$value = trim(implode(':', $t));
if ($value != '')
{
if (is_numeric($value))
$this->headers[$name] = (int)$value;
else
$this->headers[$name] = $value;
}
}
}
if (isset($this->headers['icymetaint']))
{
$metainterval = $this->headers['icymetaint'];
$intervals = 0;
$metadata = '';
while(1)
{
$data = '';
while(!feof($sock))
{
$data .= fgetc($sock);
if (strlen($data) >= $metainterval)
break;
}
$len = join(unpack('c', fgetc($sock))) * 16;
if ($len > 0)
{
$metadata = str_replace("\0", '', fread($sock, $len));
break;
}
else
{
$intervals++;
if ($intervals > 100) break;
}
}
$metarr = explode(';', $metadata);
foreach ($metarr as $meta)
{
$t = explode('=', $meta);
if (isset($t[0]) && trim($t[0]) != '')
{
$name = preg_replace('/[^a-z][^a-z0-9]*/i','', strtolower(trim($t[0])));
array_shift($t);
$value = trim(implode('=', $t));
if (substr($value, 0, 1) == '"' || substr($value, 0, 1) == "'")
$value = substr($value, 1);
if (substr($value, -1) == '"' || substr($value, -1) == "'")
$value = substr($value, 0, -1);
if ($value != '')
{
$tmp = &$this->metadata;
$tmp[$name] = $value;
}
}
}
$this->valid = true;
}
else
{
$this->valid = false;
}
fclose($sock);
}
else
echo 'unable to write.';
}
else
//echo 'no socket '.$errno.' - '.$errstr.'.';
;
}

Answer 1

You can use .xspf mountpoint extension, get XML and parse it:
<?php
$stream_url = "http://radio.hbr1.com:19800/tronic.ogg";
$xspf_url = $stream_url . ".xspf";
$xml = file_get_contents($xspf_url);
if($xml){
$data = simplexml_load_string($xml);
// Track artist
print $data->trackList->track->creator;
// Track title
print $data->trackList->track->title;
}
?>
Here is how .xspf data looks like (I use lynx to read the URL content):
$ lynx -mime_header http://radio.hbr1.com:19800/tronic.ogg.xspf
HTTP/1.0 200 OK
Content-Type: application/xspf+xml
Content-Length: 615
<?xml version="1.0" encoding="UTF-8"?>
<playlist xmlns="http://xspf.org/ns/0/" version="1">
<title/>
<creator/>
<trackList>
<track>
<location>http://radio.hbr1.com:19800/tronic.ogg</location>
<creator>Res Q</creator>
<title>Fakesleep (2012)</title>
<annotation>Stream Title: HBR1 - Tronic Lounge
Stream Description: Music on Futurenet
Content Type:application/ogg
Bitrate: Quality 0,00
Current Listeners: 28
Peak Listeners: 45
Stream Genre: Tech House, Progressive House, Electro, Minimal</annotation>
<info>http://www.hbr1.com</info>
</track>
</trackList>
</playlist>
As you can see /playlist/trackList/track/title XML node is your song title, /playlist/trackList/track/creator is usually an artist.

Answer 2

That's because you are only trying to parse the braindead ancient metadata slipstreaming introduced by Nullsoft in Shoutcast.
Proper streams use a container (e.g. Ogg or WebM) instead of throwing raw data out.
Newer Icecast servers offer a JSON API (Version 2.4.1 and above). This is more useful than pulling in a whole stream just for the metadata.
If you are decoding the stream anyway, then you should look into proper libraries for parsing streams, libogg, libopus, libvorbis come to mind.