PHP VideoStream class for HTML5 video streaming

VideoStream.php

<?php
/**
 * Description of VideoStream
 *
 * @author Rana 
 * Customized by Daym for remote videos 
 * @link http://codesamplez.com/programming/php-html5-video-streaming-tutorial
 */
class VideoStream
{
    private $path = "";
    private $stream = "";
    private $buffer = 102400;
    private $start  = -1;
    private $end    = -1;
    private $size   = 0;
 
    function __construct($filePath) 
    {
        $this->path = $filePath;
    }
     
    /**
    * Remote file size
    */
    public function getFileSize($file){
        if(!empty($file)){
            $this->path = $file;
            foreach(get_headers($file) as $head){
                if(strpos($head, 'Content-Length:') === 0){
                    return str_replace('Content-Length: ', '', $head);
                }
            }
        }
        return 0;
    }

    /**
    * Fetches the remote partial content
    */
    public function getRange($url,$start,$end){
        $ch = curl_init();
        curl_setopt($ch, CURLOPT_URL, $url);
        curl_setopt($ch, CURLOPT_HTTPHEADER, array(
        'Range: bytes=' . $start . '-' . $end,
        ));
        $content = curl_exec($ch);
        curl_close($ch); 
        return $content;
    }
    /**
     * Set proper header to serve the video content
     */
    private function setHeader()
    {
        ob_get_clean();
        header("Content-Type: video/mp4");
        header("Cache-Control: max-age=2592000, public");
        header("Expires: ".gmdate('D, d M Y H:i:s', time()+2592000) . ' GMT');
        header("Last-Modified: ".gmdate('D, d M Y H:i:s', @filemtime($this->path)) . ' GMT' );
        $this->start = 0;
        $this->size  = $this->getFileSize($this->path);
        $this->end   = $this->size - 1;
        header("Accept-Ranges: 0-".$this->end);
         
        if (isset($_SERVER['HTTP_RANGE'])) {
  
            $c_start = $this->start;
            $c_end = $this->end;
 
            list(, $range) = explode('=', $_SERVER['HTTP_RANGE'], 2);
            if (strpos($range, ',') !== false) {
                header('HTTP/1.1 416 Requested Range Not Satisfiable');
                header("Content-Range: bytes $this->start-$this->end/$this->size");
                exit;
            }
            if ($range == '-') {
                $c_start = $this->size - substr($range, 1);
            }else{
                $range = explode('-', $range);
                $c_start = $range[0];
                 
                $c_end = (isset($range[1]) && is_numeric($range[1])) ? $range[1] : $c_end;
            }
            $c_end = ($c_end > $this->end) ? $this->end : $c_end;
            if ($c_start > $c_end || $c_start > $this->size - 1 || $c_end >= $this->size) {
                header('HTTP/1.1 416 Requested Range Not Satisfiable');
                header("Content-Range: bytes $this->start-$this->end/$this->size");
                exit;
            }
            $this->start = $c_start;
            $this->end = $c_end;
            $length = $this->end - $this->start + 1;
            header('HTTP/1.1 206 Partial Content');
            header("Content-Length: ".$length);
            header("Content-Range: bytes $this->start-$this->end/".$this->size);
        }
        else
        {
            header("Content-Length: ".$this->size);
        }  
         
    }
    
     
    /**
     * perform the streaming of calculated range
     */
    private function stream()
    {
       echo $this->getRange($this->path,$this->start,$this->end);
    }

    /**
     * Start streaming video content
     */
    function start()
    {
        $this->setHeader();
        $this->stream();
    }
}