FM/nixtape/utils/oggclass/ogg.class.php

<?php 
/*  Ogg (vorbis/theora) php manipulation library  v1.3g
	by Nicolas Ricquemaque <f1iqf@hotmail.com>

      GNU GPL >= 2.1  http://www.gnu.org/copyleft/lesser.html GNU LGPL

      Primary for use with itheora  http://menguy.aymeric.free.fr/theora/   */
	  
define("OGGCLASSVERSION", " [Ogg.class.php v1.3g]");
define("CACHING",0);
define("ANSI",0);
define("NOCACHING",1);
define("UTF8",2);
define("NOVENDORTAG",4);
define("UPDATECACHE",8);
	
class Ogg
{ 
// Public variables
var $LastError=false; 	// false if no error occured, else error text
var $Streams=array();	// All the file data stored here

// Private variables
var $Data;
var $cache,$cachedir; 	// shall we use & write cache and where ?
var $tagvendor; 		// change it to false if you don't want the oggclass to add its name to your vendor field when writting new comments
var $StreamsUTF8; 		// if true, the vendor and comment information will be in utf8 inside the Streams array. Else, will be ansi.
var $InputFile,$OutputFile,$MaxTime=0,$refresh;

// constructor; $options contains a conbination of (CACHING or NOCACHING) + (ANSI or UTF8) + NOVENDORTAG + UPDATECACHE
// by default $options enables CACHING, ANSI strings and Vendor Tag tagging
// UPDATECACHE is forcing the analysing of the file and the update of the cache, if caching enabled.
// $cachedir is optional cache directory
function Ogg ($OggFile, $options=0, $cachedir="/cache.ogg") 
	{
	// Check php version
	if (intval(PHP_VERSION)<4) return($this->creturn("PHP version must me >= 4 but we show PHP v".PHP_VERSION));
	
	// Options
	$this->StreamsUTF8=($options&UTF8)>0;
	$this->cache=($options&NOCACHING)==0;
	$this->tagvendor=($options&NOVENDORTAG)==0;
	
	clearstatcache(); 
	$this->Streams['oggfile']=$OggFile; 	
	if ((strpos($OggFile,"://")===false)&&!file_exists($this->realpath($OggFile))) return ($this->creturn("Inexisting OGG file ".$OggFile));

	// handle caching
	if ($this->cache) 
		{
		$this->cachedir=rtrim($cachedir,"/");	
		if (!is_dir($this->realpath($this->cachedir))) @mkdir ($this->realpath($this->cachedir)); 
		$cache=$this->cachedir."/".strtr($this->Streams['oggfile'],"/:?&#","-----").".cache";
		$this->Streams['cachefile']=$cache;
		if ((($options&UPDATECACHE)==0)&&is_resource($cachefile = @fopen($this->realpath($this->Streams['cachefile']), "r")))
			{
			if ($s=fread($cachefile,filesize($this->realpath($this->Streams['cachefile']))))	
				{
				$this->Streams=unserialize($s);
				$this->Streams['picturable']=$this->Picturable(); // Can the server extract a picture ? better check again.
				// Adapt string encoding to what's required by user
				if (isset($this->Streams['summary'])) $this->Streams['summary']=$this->Decode($this->Streams['summary']);
				if (isset($this->Streams['theora']['vendor'])) $this->Streams['theora']['vendor']=$this->Decode($this->Streams['theora']['vendor']);
				if (isset($this->Streams['vorbis']['vendor'])) $this->Streams['vorbis']['vendor']=$this->Decode($this->Streams['vorbis']['vendor']);
				if (isset($this->Streams['theora']['comments'])) foreach ($this->Streams['theora']['comments'] as $key => $comment) $this->Streams['theora']['comments'][$key]=$this->Decode($comment);
				if (isset($this->Streams['vorbis']['comments'])) foreach ($this->Streams['vorbis']['comments'] as $key => $comment) $this->Streams['vorbis']['comments'][$key]=$this->Decode($comment);			
				$this->Streams['encoding']=$this->StreamsUTF8?"utf-8":"ansi";
				// double-check if the file we found in cache is really the one we should have, by comparing their sizes, for local files only
				if ((strpos($OggFile,"://")===false)&&($this->Streams['size']!=filesize($this->realpath($this->Streams['oggfile'])))) unset($this->Streams['source']);
				$this->creturn(true);
				}
			fclose($cachefile);
			$this->Streams['cachefile']=$cache;
			//echo "<!--\n".print_r($this->Streams,true)."-->\n";
			}	
		}		
	
	//if file could not be read from cache (or sizes did not match), we parse it from file
	if (!isset($this->Streams['source'])) $this->analyze(); 
	
	// Now check if a write has been left in progress (for local files only)
	if ((strpos($OggFile,"://")===false)&&($tmp=glob($this->realpath($this->Streams['oggfile']."*.tmp"))))
		{
		if (count($tmp)==1) $this->Streams['tmpfile']=$tmp[0];
		elseif (count($tmp)>1) // if there is several possible files, use the last one, delete others
			{
			$this->Streams['tmpfile']=$tmp[0];
			foreach ($tmp as $file) 
				if (filemtime($file)>filemtime($this->Streams['tmpfile'])) 
					{
					@unlink($this->Streams['tmpfile']); // supress old uncompleted tmp file
					$this->Streams['tmpfile']=$file;
					}			
			}			
		if (isset($this->Streams['tmpfile'])) 
			{
			$this->Streams['tmpfile']=substr($this->Streams['tmpfile'],strpos($this->Streams['tmpfile'],$this->Streams['oggfile']));
			list($this->refresh,$this->Streams['tmpfileptr']) = sscanf($this->Streams['tmpfile'],$this->Streams['oggfile'].".r%d.p%d.tmp");	
			}
		}
	}

// Public methods
function GetPicture ($framepos=1,$where=false) //return $path of picture or false; $frame=frame number; $where=path to file to create, if false will be in cache; 
	{
	if (!$this->Streams['picturable'])
		{
		if (!$this->Picturable()) return(false);
		else $this->Streams['picturable']=true;
		}
	if (isset($this->Streams['theora']['pictures']))
		{	
		if (isset($this->Streams['theora']['pictures'][$framepos])) 
			{
			if (file_exists($this->realpath($this->Streams['theora']['pictures'][$framepos]))) return ($this->Streams['theora']['pictures'][$framepos]);
			}
		}	
	if (!$this->cache && !$where) return($this->creturn("If the CACHING is disabled, you got to provide a path to your picture..."));
	$file=$where?$where:substr($this->Streams['cachefile'],0,-6).".f$framepos.jpg";
	if (file_exists($this->realpath($file))) // picture seem to have previously alread been computed, but is not in cache: either cache was relaculated and information was lost, or caching is disabled
		{ // we use the picture we found, avoiding wasting server time to recalculate
		if (!isset($this->Streams['theora']['pictures'])) $this->Streams['theora']['pictures']=array();
		$this->Streams['theora']['pictures'][$framepos]=$file;
		if ($this->cache) $this->CacheUpdate();
		$this->creturn(true);
		return($file);
		}
	$errorreport=error_reporting(0);
	$movie = new ffmpeg_movie($this->Streams['oggfile'],false);
	if (!$movie) { error_reporting($errorreport); return($this->creturn("Unable to extract a picture from ".$this->Streams['oggfile'])); }
	$frame=$movie->getFrame($framepos);
	if (!$frame) { error_reporting($errorreport); return($this->creturn("Unable to extract the frame #".$framepos." from ".$this->Streams['oggfile'])); }
	$image=$frame->toGDImage();
	if (!$image) { error_reporting($errorreport); return($this->creturn("Unable to extract an image in frame #".$framepos." from ".$this->Streams['oggfile'])); }	
	if (!imagejpeg($image,$this->realpath($file))) { error_reporting($errorreport); return($this->creturn("Unable to save a jpeg image from frame #".$framepos." from ".$this->Streams['oggfile'])); }
	if (!isset($this->Streams['theora']['pictures'])) $this->Streams['theora']['pictures']=array();
	$this->Streams['theora']['pictures'][$framepos]=$file;
	if ($this->cache) $this->CacheUpdate();
	error_reporting($errorreport);
	$this->creturn(true);
	return($file);
	}


function WriteNewComments ($refresh=5) 
	{
	if ((strpos($this->Streams['oggfile'],"://")!==false)) return ($this->creturn("It is not possible to change the comment tags on a remote server ! ")); 
	
	$this->InputFile= fopen($this->realpath($this->Streams['oggfile']), "rb");
	if (!is_resource($this->InputFile)) return ($this->creturn("Could not open OGG file ".$this->Streams['oggfile'])); 
	if ($this->Streams['source']=='cache') 
		if (! ($this->Data = fread($this->InputFile, 0xFFFF)) )
			return ($this->creturn("Could not read in OGG file ".$this->Streams['oggfile']));
	
	if (isset($this->Streams['vorbis']['commentpos'])) 
		{
		$vorbispacket=$this->PackComments($this->Streams['vorbis']);
		if (!$vorbispacket) return (false);
		}
	else $vorbispacket=false;
		
	if (isset($this->Streams['theora']['commentpos'])) 
		{
		$theorapacket=$this->PackComments($this->Streams['theora']);
		if (!$theorapacket) return (false);
		}
	else $theorapacket=false;
	
	if (!$vorbispacket && !$theorapacket) return ($this->creturn("Could not find a stream to comment !"));
	
	// Make sure the refresh time will not exceed the script time limit
	if ((get_cfg_var("max_execution_time")>0)&&($refresh>=get_cfg_var("max_execution_time"))) $this->refresh=get_cfg_var("max_execution_time")-2;
	else $this->refresh=$refresh;
		
	$this->MaxTime=time()+$this->refresh;
	$this->Streams['tmpfile']=$this->Streams['oggfile'].".r".$this->refresh;
	@unlink($this->realpath($this->Streams['tmpfile']));
	$this->OutputFile= fopen($this->realpath($this->Streams['tmpfile']), "wb");
	if (!is_resource($this->OutputFile)) return ($this->creturn("Could not create temp file ".$this->Streams['tmpfile']));
	
	if ($vorbispacket&&$theorapacket)
		{
		if ($this->Streams['vorbis']['commentpos']<$this->Streams['theora']['commentpos'])
			{
			if ($this->Streams['vorbis']['commentpos']>0) fwrite($this->OutputFile,substr($this->Data,0,$this->Streams['vorbis']['commentpos']));
			fwrite($this->OutputFile,$vorbispacket);
			if ($this->Streams['vorbis']['commentnext']<$this->Streams['theora']['commentpos']) 
				fwrite($this->OutputFile,substr($this->Data,$this->Streams['vorbis']['commentnext'],$this->Streams['theora']['commentpos']-$this->Streams['vorbis']['commentnext']));
			fwrite($this->OutputFile,$theorapacket);
			if ($this->Streams['theora']['commentnext']<strlen($this->Data)) fwrite($this->OutputFile,substr($this->Data,$this->Streams['theora']['commentnext']));				
			}
		else
			{
			if ($this->Streams['theora']['commentpos']>0) fwrite($this->OutputFile,substr($this->Data,0,$this->Streams['theora']['commentpos']));
			fwrite($this->OutputFile,$theorapacket);
			if ($this->Streams['theora']['commentnext']<$this->Streams['vorbis']['commentpos']) 
				fwrite($this->OutputFile,substr($this->Data,$this->Streams['theora']['commentnext'],$this->Streams['vorbis']['commentpos']-$this->Streams['theora']['commentnext']));
			fwrite($this->OutputFile,$vorbispacket);
			if ($this->Streams['vorbis']['commentnext']<strlen($this->Data)) fwrite($this->OutputFile,substr($this->Data,$this->Streams['vorbis']['commentnext']));	
			}
		}
	elseif ($vorbispacket)
		{
		if ($this->Streams['vorbis']['commentpos']>0) fwrite($this->OutputFile,substr($this->Data,0,$this->Streams['vorbis']['commentpos']));
		fwrite($this->OutputFile,$vorbispacket);
		if ($this->Streams['vorbis']['commentnext']<strlen($this->Data)) fwrite($this->OutputFile,substr($this->Data,$this->Streams['vorbis']['commentnext']));	
		}
	else {
		if ($this->Streams['theora']['commentpos']>0) fwrite($this->OutputFile,substr($this->Data,0,$this->Streams['theora']['commentpos']));
		fwrite($this->OutputFile,$theorapacket);
		if ($this->Streams['theora']['commentnext']<strlen($this->Data)) fwrite($this->OutputFile,substr($this->Data,$this->Streams['theora']['commentnext']));	
		}

	return($this->ContinueWrite());
	}

	
function ContinueWrite()
	{
	if ($this->MaxTime==0) // not called from WriteNewComments()
		{	
		$this->InputFile=fopen($this->realpath($this->Streams['oggfile']),"rb");
		if (!is_resource($this->InputFile)) return ($this->creturn("Could not open OGG file ".$this->Streams['oggfile'])); 		
		$this->OutputFile=fopen($this->realpath($this->Streams['tmpfile']),"ab");
		if (!is_resource($this->OutputFile)) { fclose($this->InputFile); return ($this->creturn("Could not open tmp file ".$this->Streams['tmpfile'])); }			
		$this->MaxTime=time()+$this->refresh;
		fseek($this->InputFile,$this->Streams['tmpfileptr']); 
		fseek($this->OutputFile,0,SEEK_END);
		}
			
	$interupted=false;
	while (!feof($this->InputFile)) 
		{
		fwrite($this->OutputFile,fread($this->InputFile,0xFFFF));
		if (time()>=$this->MaxTime) { $interupted=ftell($this->InputFile); break; }
		}
	fclose($this->InputFile);
	fclose($this->OutputFile);	
	$this->MaxTime=0;	//timer reset
	if ($interupted)
		{	
		@rename($this->realpath($this->Streams['tmpfile']),$this->realpath($this->Streams['oggfile'].".r".$this->refresh.".p".$interupted.".tmp"));
		$this->Streams['tmpfile']=$this->Streams['oggfile'].".r".$this->refresh.".p".$interupted.".tmp";
		return($this->Streams['tmpfileptr']=$interupted);
		}

	unlink($this->realpath($this->Streams['oggfile']));
	rename($this->realpath($this->Streams['tmpfile']),$this->realpath($this->Streams['oggfile']));
	$this->analyze(); // update cache 
	return($this->Streams['size']);
	}
	
function CacheUpdate() // update cache file
	{
	if (!$this->cache) return($this->creturn("CACHING disabled, therefore updating cache is not possible..."));
	if (is_resource($cachefile = fopen($this->realpath($this->Streams['cachefile']), "w")))
		{
		$src=$this->Streams['source'];
		$cache=$this->Streams['cachefile'];
		$this->Streams['source']="cache";
		unset ($this->Streams['cachefile']);
		fputs($cachefile, serialize($this->Streams));
		$this->Streams['source']=$src;
		$this->Streams['cachefile']=$cache;
		fclose($cachefile);
		return($this->creturn(true));
		}
	else return($this->creturn("Writting cache file unsuccessfull"));
	}
	
// Private methods
function creturn($error=false)	{ if (is_string($error)) { $this->LastError="OGG Error: $error"; return(false); } else { $this->LastError=false; return($error); } }
function Decode($string) 	
	{
	if ($this->StreamsUTF8) return((utf8_encode(utf8_decode($string)) == $string)?$string:utf8_encode($string)); // if string utf8, return it, or encode it in utf8
	else return((utf8_encode(utf8_decode($string)) == $string)?utf8_decode($string):$string); // return ansi
	} 
function EncodeUTF8($string) 	{ return((utf8_encode(utf8_decode($string)) == $string)?$string:utf8_encode($string)); } 
function Read32LE(&$buffer,$pos) { return(ord($buffer[$pos+0])+(ord($buffer[$pos+1])<<8)+(ord($buffer[$pos+2])<<16)+(ord($buffer[$pos+3])<<24)); } // Read 32 bits little endian from buffer from index $pos	
function readBits ($nb,&$buffer,&$bitptr) //read and decodes an integer up to 32 bits from the buffer
	{
	if ($nb>32) $nb=32;
	if ($nb==0) return(0);		
	for ($bit=$nb,$r=0;$bit>0;$bit--,$bitptr++) $r+=(ord(substr($buffer,$bitptr>>3,1))&pow(2,7-$bitptr%8))>0?pow(2,$bit-1):0;			
	return ($r);	
	}
function realpath($path) // if a path to a file is absolute, add document_root
	{ 
	if ((strpos($path,$_SERVER['DOCUMENT_ROOT'])!==false)||(strpos($path,"://")!==false)) return($path); // path already absolute or remote
	elseif ($path[0]=='/') return str_replace("//","/",$_SERVER['DOCUMENT_ROOT'].$path); 
	else return($path); // relative path
	} 
function Picturable() //boolean, says if this server/library is able to extract a picture from movie
	{
	if (!isset($this->Streams['theora'])) return($this->creturn("Only for video streams..."));
	if ((strpos($this->Streams['oggfile'],"://")!==false)) return ($this->creturn("Picture extraction not possible on a remote server ! ")); 
	$extensions=get_loaded_extensions();
	if  (!in_array("ffmpeg",$extensions)) return($this->creturn("Module ffmpeg not found on this PHP server !"));
	if ($gd=in_array("gd",$extensions))
		{
		$GDArray=gd_info();
		if (intval(ereg_replace('[[:alpha:][:space:]()]+', '', $GDArray['GD Version'])) < 2) $gd=false;
		}
	if (!gd) return($this->creturn("Module gd2 not found on this PHP server !"));
	return($this->creturn(true));
	}

	
function crcOgg (&$str) 			// add a CRC to an ogg page $str (including headers, crc set to 0)
	{
	$crc=0;
	$polynom=0x04C11DB7;
	for ($i=0; $i<strlen($str); $i++)
		{
		$c = ord($str[$i]);
		for ($j=0; $j<8; $j++)
			{
			$bit=0;
			if ($crc&0x80000000) $bit=1;
			if ($c&0x80) $bit^=1;
			$c<<=1;	$crc<<=1;
			if ($bit) $crc^=$polynom;
			}
		}
	$str[22]=chr($crc&0xFF); $str[23]=chr(($crc>>8)&0xFF); $str[24]=chr(($crc>>16)&0xFF); $str[25]=chr(($crc>>24)&0xFF); 
	}
		
function PackComments ($stream)
	{
	if ($this->tagvendor && (strpos($stream['vendor'],OGGCLASSVERSION)===false)) $stream['vendor'].=OGGCLASSVERSION;
	// check that no empty comments or array
	if (isset($stream['comments'])) { foreach ($stream['comments'] as $key=>$comment) if (!strlen($comment)) unset($stream['comments'][$key]); }
	else $stream['comments']=array();			
	$data=(isset($stream['channels'])?chr(0x03)."vorbis":chr(0x81)."theora").pack("V",strlen($this->EncodeUTF8($stream['vendor']))).$this->EncodeUTF8($stream['vendor']).pack("V",count($stream['comments']));
	foreach ($stream['comments'] as $comment) 
		{
		if (!preg_match("`\A[A-Za-z]*=.+`",$comment)) return($this->creturn("Invalid comment format : ".$comment)); 
		$data.=pack("V",strlen($this->EncodeUTF8(($comment)))).$this->EncodeUTF8($comment); 
		}
	if (isset($stream['channels'])) $data.=chr(0x01);		// vorbis stream adds this
	$segments=1+(strlen($data)>>8); 
	$packet="OggS".pack("CCVVVVVC",0,0,0,0,$stream['serial'],1,0,$segments+strlen($stream['commentleftSegments']));
	for ($i=0;$i<($segments-1);$i++) $packet.=chr(0xFF);
	$packet.=chr(strlen($data)%0xFF);
	if (strlen($stream['commentleftSegments'])>0) $packet.=$stream['commentleftSegments'];	
	$packet.=$data;	
	if (($stream['commentpos']+$stream['commentlen'])<$stream['commentnext']) $packet.=substr($this->Data,$stream['commentpos']+ord($this->Data[$stream['commentpos']+26])+27+$stream['commentlen'],$stream['commentnext']-$stream['commentpos']-$stream['commentlen']-27-ord($this->Data[$stream['commentpos']+26]));	
	$this->crcOgg($packet);
	return($packet);
	}

function analyze() // Parse headers to retrieve identification and comments infos
	{	
	clearstatcache();
	
	unset($this->Streams['vorbis']); unset($this->Streams['theora']); 
	unset($this->Streams['tmpfile']); unset($this->Streams['tmpfileptr']); 
	unset($this->Streams['size']); unset($this->Streams['duration']);

	$this->Streams['source']="file";
	$this->Streams['encoding']=$this->StreamsUTF8?"utf-8":"ansi";
	$this->Data="";
	
	if (strpos($this->Streams['oggfile'],"http://")!==false) // If remote file
		{
		$url = parse_url($this->Streams['oggfile']);
		$port = isset($url['port']) ? $url['port'] : 80;
		$inputfile = @fsockopen($url['host'], $port,$errno,$errstr,5);
		if ($inputfile)
			{
			stream_set_timeout($inputfile, 2);
			$query=isset($url['query'])?"?".$url['query']:"";
			@fwrite($inputfile, "GET ".$url['path'].$query." HTTP/1.1\r\nHost: ".$url['host']."\r\nUser-Agent:".OGGCLASSVERSION."\r\nConnection: close\r\n\r\n");
			for ($i=0;$i<66;$i++) if (!feof($inputfile)) $this->Data.=@fread($inputfile, 1024);	else break;
			preg_match('/Content-Length: ([0-9]+)/', $this->Data, $length);
			if (isset($length[1])) $this->Streams['size']=$length[1];
			fclose($inputfile);
			}
		}
		
	if (strpos($this->Data,"OggS")===false) // not a remote file or could cold read inside it
		{
		$inputfile = @fopen($this->realpath($this->Streams['oggfile']), "rb");
		if ($s=@filesize($this->realpath($this->Streams['oggfile']))) $this->Streams['size']=$s;
		if (!is_resource($inputfile)) return ($this->creturn("Could not open OGG file ".$this->Streams['oggfile']));
		// First read the first 65536 bytes of the file to parse identification and comments headers
		if (! ($this->Data = fread($inputfile, 0xFFFF))) return ($this->creturn("Could not read in OGG file ".$this->Streams['oggfile']));
		}
	
	$this->Streams['summary']=basename($this->Streams['oggfile'])." (".floor($this->Streams['size']/1024)." kB)\n\n";		
	for ($pos=0;($pos=strpos($this->Data,"OggS",$pos))!==false;$pos++) // parse OGG pages to retrieve interresting data
		{
		if (ord($this->Data[$pos+4])!=0) continue; // unknown stream structure version. We continue parsing, but don't analyse this one which might be a sync problem
		$packet=$pos+27+ord($this->Data[$pos+26]); // offset of the packet after header
		if (isset($this->Streams['cmml']) && $this->Read32LE($this->Data,$pos+14)==$this->Streams['cmml']['serial']) // read CMML data
			{
			$nextogg=strpos($this->Data,"OggS",$pos+1);
			if (isset($this->Streams['cmml']['text'])) $this->Streams['cmml']['text'].="\n";
			$this->Streams['cmml']['text'].=substr($this->Data,$packet,$nextogg-$packet);
			}
		if ($this->Read32LE($this->Data,$pos+18)==0) // Page Count = 0 : we can find the stream type and read identification headers
			{				
			if ((substr($this->Data,$packet+1,6)=="vorbis") && !isset($this->Streams['vorbis'])) // decode vorbis identification header
				{
				$this->Streams['vorbis']=array(); 
				$vorbis=&$this->Streams['vorbis'];
				$vorbis['serial']=$this->Read32LE($this->Data,$pos+14);   
		        if (ord($this->Data[$packet]) != 0x01) return($this->creturn(sprintf("Incorrect Vorbis Identification Header(0x%x)",ord($this->Data[$packet]))));
		        if ($this->Read32LE($this->Data,$packet+7)!=0) return($this->creturn("Incorrect Vorbis stream version = ".$this->Read32LE($this->Data,$packet+7)));	  
		        if (($vorbis['channels'] = ord($this->Data[$packet+11])) == 0) return($this->creturn("Incorrect Vorbis channels number = ".ord($this->Data[$packet+11])));
		        if (($vorbis['samplerate']= $this->Read32LE($this->Data,$packet+12)) == 0) return($this->creturn("Incorrect Vorbis sample rate = ".$this->Read32LE($this->Data,$packet+12))); 
		        $vorbis['maxbitrate'] = $this->Read32LE($this->Data,$packet+16);
		        $vorbis['nombitrate'] = $this->Read32LE($this->Data,$packet+20);
				$vorbis['minbitrate'] = $this->Read32LE($this->Data,$packet+24);
				$vorbis['bitrate']=($vorbis['nombitrate'] != 0)?$vorbis['nombitrate']:($vorbis['minbitrate'] + $vorbis['maxbitrate']) / 2;
				}				
			elseif ((substr($this->Data,$packet+1,6)=="theora") && !isset($this->Streams['theora'])) // decode theora identification header
				{
				$this->Streams['theora']=array(); 
				$theora=&$this->Streams['theora'];
				$theora['serial']=$this->Read32LE($this->Data,$pos+14);  			
				if (ord($this->Data[$packet]) != 0x80) return($this->creturn(sprintf("Incorrect Theora Identification Header(0x%x)",ord($this->Data[$packet])))); 
				if ((($theora['vmaj']=ord($this->Data[$packet+7]))!=3) || (($theora['vmin']=ord($this->Data[$packet+8]))!=2)) return($this->creturn("Incorrect Theora stream version"));
				$bitptr=($packet+9)*8; 	
				$theora['vrev']=$this->readBits(8,$this->Data,$bitptr); 
				$theora['fmbw']=$this->readBits(16,$this->Data,$bitptr); $theora['fmbh']=$this->readBits(16,$this->Data,$bitptr);
				$theora['picw']=$this->readBits(24,$this->Data,$bitptr); $theora['pich']=$this->readBits(24,$this->Data,$bitptr);
				$theora['picx']=$this->readBits(8,$this->Data,$bitptr); $theora['picy']=$this->readBits(8,$this->Data,$bitptr);
				$theora['width']=$theora['picw']; $theora['height']=$theora['pich']; 
				$theora['frn']=$this->readBits(32,$this->Data,$bitptr); $theora['frd']=$this->readBits(32,$this->Data,$bitptr); $theora['frate']=round($theora['frn']/$theora['frd'],2);
				$theora['parn']=$this->readBits(24,$this->Data,$bitptr); $theora['pard']=$this->readBits(24,$this->Data,$bitptr); if ($theora['parn']*$theora['pard']!=0) $theora['pixelaspectratio']=$theora['parn'].":".$theora['pard']; else $theora['pixelaspectratio']="1:1";
				$theora['cs']=$this->readBits(8,$this->Data,$bitptr); if ($theora['cs']==1) $theora['colorspace']="Rec. 470M"; elseif ($theora['cs']==2) $theora['colorspace']="Rec. 470BG";
				$theora['nombr']=$this->readBits(24,$this->Data,$bitptr);
				$theora['qual']=$this->readBits(6,$this->Data,$bitptr);
				$theora['kfgshift']=$this->readBits(5,$this->Data,$bitptr);
				$theora['pf']=$this->readBits(2,$this->Data,$bitptr); if ($theora['pf']==0) $theora['pixelformat']="4:2:0"; elseif ($theora['pf']==2) $theora['pixelformat']="4:2:2"; elseif ($theora['pf']==3) $theora['pixelformat']="4:4:4";				
				}
			elseif ((substr($this->Data,$packet,8)=="fishead\0")&& !isset($this->Streams['skeleton'])) //decode ogg skeleton primary header
				{
				$this->Streams['skeleton']=array();
				$this->Streams['skeleton']['version']=(ord($this->Data[$packet+8])+(ord($this->Data[$packet+9])<<8)).".".(ord($this->Data[$packet+10])+(ord($this->Data[$packet+11])<<8));
				if (ord($this->Data[$packet+44])>0) $this->Streams['skeleton']['utc']=substr($this->Data,$packet+44,20);
				}
			elseif ((substr($this->Data,$packet,8)=="CMML\0\0\0\0")&& !isset($this->Streams['cmml'])) //decode ogg CMML primary header
				{
				$this->Streams['cmml']=array();
				$this->Streams['cmml']['serial']=$this->Read32LE($this->Data,$pos+14);
				$this->Streams['cmml']['version']=(ord($this->Data[$packet+8])+(ord($this->Data[$packet+9])<<8)).".".(ord($this->Data[$packet+10])+(ord($this->Data[$packet+11])<<8));
				}
			}
		elseif ($this->Read32LE($this->Data,$pos+18)==1) // Page Count = 1 : we can read comments headers
			{
			$type=substr($this->Data,$packet+1,6);
			if ($type=="vorbis") 
				{
				if (ord($this->Data[$packet])!=0x03) return($this->creturn(sprintf("Incorrect Vorbis Comment Header(0x%x)",ord($this->Data[$packet])))); 
				$table=&$this->Streams['vorbis'];
				}
			elseif ($type=="theora") 
				{
				if (ord($this->Data[$packet])!=0x81) return($this->creturn(sprintf("Incorrect Theora Comment Header(0x%x)",ord($this->Data[$packet])))); 
				$table=&$this->Streams['theora'];
				}
			else continue; // unknown page 1, neither theora nor vorbis comments
			$offset=$packet;
			$lenv=$this->Read32LE($this->Data,$offset+7);
			$table['vendor']=$this->Decode(substr($this->Data,$offset+11,$lenv));
			$offset+=11+$lenv;
			$ncomments=$this->Read32LE($this->Data,$offset);
			$offset+=4;
			$table['comments']=array();		
			for ($i=0; $i<$ncomments; $i++)
				{
				$lcomment=$this->Read32LE($this->Data,$offset);
				$table['comments'][$i]=$this->Decode(substr($this->Data,$offset+4,$lcomment));
				$offset+=4+$lcomment;
				}	
			if ($type=="vorbis") $offset++; //vorbis format adds a "0x01" at the end, which theora doesn't
			$table['commentlen']=$offset-$packet; 
			// This last part only to get necessary information to change the comments tags 
			$table['commentpos']=$pos;	//page position in file
			$table['commentnext']=strpos($this->Data,"OggS",$pos+1); //next page position in file
			$lseg=ord($this->Data[$pos+26])-($table['commentlen']>>8)-1; 
			$table['commentleftSegments']=substr($this->Data,$pos+27+($table['commentlen']>>8)+1,$lseg);		
			}
		if (isset($this->Streams['vorbis']['vendor'])&&isset($this->Streams['theora']['vendor'])&&!isset($this->Streams['cmml'])) break; // we already have what we need, we can stop parsing
		}
			
	if (isset($this->Streams['skeleton'])) // read ogg skeleton secondary headers
		{
		for ($pos=0;($pos=strpos($this->Data,"fisbone\0",$pos))!==false;$pos++) // parse fisbone pages to retrieve interresting data
			{
			$serial=$this->Read32LE($this->Data,$pos+12);
			$nextfis=strpos($this->Data,"fisbone\0",$pos+1);
			$nextogg=strpos($this->Data,"OggS",$pos+1);
			$endfis=($nextfis>0 && $nextfis<$nextogg)?$nextfis:$nextogg;
			$posmessage=$pos+8+$this->Read32LE($this->Data,$pos+8);
			$lenmessage=$endfis-$posmessage;
			$message=trim(substr($this->Data,$posmessage,$lenmessage));
			if (strlen($message)>0)
				{
				if (isset($this->Streams['theora']) && $this->Streams['theora']['serial']==$serial) $this->Streams['theora']['skeleton']=$message;
				if (isset($this->Streams['vorbis']) && $this->Streams['vorbis']['serial']==$serial) $this->Streams['vorbis']['skeleton']=$message;
				}
			}
		}
		
	// Then read the last 65536 bytes of the file to get last granular pos to calculate streams duration
	$endbuffer="";
	if (isset($this->Streams['size'])&&($this->Streams['size']>0xFFFF))
		{
		if (is_resource($inputfile)) // still open: so this is local file
			{
			@fseek($inputfile,-1*0xFFFF,SEEK_END);
			if (! ($endbuffer = fread($inputfile, 0xFFFF))) return ($this->creturn("Could not read in OGG file ".$this->Streams['oggfile']));
			fclose($inputfile);
			}
		else {
			$url = parse_url($this->Streams['oggfile']);
			$port = isset($url['port']) ? $url['port'] : 80;
			$inputfile = @fsockopen($url['host'], $port,$errno,$errstr,5);
			if ($inputfile)
				{			
				stream_set_timeout($inputfile, 2);
				$query=isset($url['query'])?"?".$url['query']:"";
				@fwrite($inputfile, "GET ".$url['path'].$query." HTTP/1.1\r\nHost: ".$url['host']."\r\nUser-Agent:".OGGCLASSVERSION."\r\nAccept-Ranges: bytes\r\nRange: bytes=".($this->Streams['size']-0xFFFF)."-\r\nConnection: close\r\n\r\n");
				for ($i=0;$i<70;$i++) if (!feof($inputfile)) $endbuffer.=@fread($inputfile, 1024);	else break;
				fclose($inputfile);
				}
			}
		}
	else $endbuffer=&$this->Data;	
	for ($pos=0;($pos=strpos($endbuffer,"OggS",$pos))!==false;$pos++) // parse OGG pages to retrieve interesting data
		{
		if (isset($this->Streams['vorbis'])&&($this->Read32LE($endbuffer,$pos+6)!=-1)&&($this->Read32LE($endbuffer,$pos+14)==$this->Streams['vorbis']['serial'])&&(ord($endbuffer[$pos+5])&0x4))
			$this->Streams['vorbis']['duration']=round($this->Read32LE($endbuffer,$pos+6) / $this->Streams['vorbis']['samplerate']);

		elseif (isset($this->Streams['theora'])&&($this->Read32LE($endbuffer,$pos+6)!=-1)&&($this->Read32LE($endbuffer,$pos+14)==$this->Streams['theora']['serial'])&&(ord($endbuffer[$pos+5])&0x4))
			{
			$this->Streams['theora']['framecount']=($this->Read32LE($endbuffer,$pos+6)>>$this->Streams['theora']['kfgshift']) + ($this->Read32LE($endbuffer,$pos+6)&(pow(2,$this->Streams['theora']['kfgshift'])-1));
			$this->Streams['theora']['duration']=round( $this->Streams['theora']['framecount'] * $this->Streams['theora']['frd'] / $this->Streams['theora']['frn']); 
			}
		if (isset($this->Streams['vorbis']['duration'])&&isset($this->Streams['theora']['duration'])) break; // we alread have what we need, we can stop parsing	
		}
			
	// update summary 
	if (isset($this->Streams['theora']))
		{
		$this->Streams['summary'].="Video (theora): ";
		if (isset($this->Streams['theora']['duration'])) $this->Streams['summary'].=$this->Streams['theora']['duration']."s ";
		$this->Streams['summary'].=$this->Streams['theora']['width']."x".$this->Streams['theora']['height']; 
		$this->Streams['summary'].=" ".$this->Streams['theora']['frate']."fps";
		if ($q=$this->Streams['theora']['qual']) $this->Streams['summary'].=" Q=$q";
		$this->Streams['summary'].="\n";
		if (isset($this->Streams['theora']['comments'])) foreach ($this->Streams['theora']['comments'] as $value) $this->Streams['summary'].="$value\n";
		$this->Streams['summary'].="\n";
		}
	if (isset($this->Streams['vorbis']))
		{
		$this->Streams['summary'].="Audio (Vorbis";
		$this->Streams['summary'].=" ".floor($this->Streams['vorbis']['bitrate']/1000)."kb/s";
		$this->Streams['summary'].="): ";
		if (isset($this->Streams['vorbis']['duration'])) $this->Streams['summary'].=$this->Streams['vorbis']['duration']."s ";
		$this->Streams['summary'].=($this->Streams['vorbis']['channels']>1)?"stereo":"mono";
		$this->Streams['summary'].=" ".floor($this->Streams['vorbis']['samplerate']/1000)."kB/s\n";
		if (isset($this->Streams['vorbis']['comments'])) foreach ($this->Streams['vorbis']['comments'] as $value) $this->Streams['summary'].="$value\n";
		}
		
	//global duration is the biggest of each
	if (isset($this->Streams['vorbis']['duration'])&&isset($this->Streams['theora']['duration'])) $this->Streams['duration']=$this->Streams['vorbis']['duration']>$this->Streams['theora']['duration']?$this->Streams['vorbis']['duration']:$this->Streams['theora']['duration'];
	elseif (isset($this->Streams['vorbis']['duration'])) $this->Streams['duration']=$this->Streams['vorbis']['duration'];
	elseif (isset($this->Streams['theora']['duration'])) $this->Streams['duration']=$this->Streams['theora']['duration'];

	$this->Streams['picturable']=$this->Picturable(); // Can the server extract a picture ?
	if ($this->cache) $this->CacheUpdate();
	return($this->creturn(true));	
	}
}
?>