So I found this beautifull script for FLV video format Http Pseudo Streaming but in is in PHP ( found on http://stream.xmoov.com/ )

So does any one know opensource translations or can translate such PHP code into C#?

<?php
    /*

        xmoov-php 1.0
        Development version 0.9.3 beta

        by: Eric Lorenzo Benjamin jr. webmaster (AT) xmoov (DOT) com
        originally inspired by Stefan Richter at flashcomguru.com
        bandwidth limiting by Terry streamingflvcom (AT) dedicatedmanagers (DOT) com

        This work is licensed under the Creative Commons Attribution-NonCommercial-ShareAlike 3.0 License.
        For more information, visit http://creativecommons.org/licenses/by-nc-sa/3.0/
        For the full license, visit http://creativecommons.org/licenses/by-nc-sa/3.0/legalcode 
        or send a letter to Creative Commons, 543 Howard Street, 5th Floor, San Francisco, California, 94105, USA.


    */






    //  SCRIPT CONFIGURATION

    //------------------------------------------------------------------------------------------
    //  MEDIA PATH
    //
    //  you can configure these settings to point to video files outside the public html folder.
    //------------------------------------------------------------------------------------------

    // points to server root
    define('XMOOV_PATH_ROOT', '');

    // points to the folder containing the video files.
    define('XMOOV_PATH_FILES', 'video/');



    //------------------------------------------------------------------------------------------
    //  SCRIPT BEHAVIOR
    //------------------------------------------------------------------------------------------

    //set to TRUE to use bandwidth limiting.
    define('XMOOV_CONF_LIMIT_BANDWIDTH', TRUE);

    //set to FALSE to prohibit caching of video files.
    define('XMOOV_CONF_ALLOW_FILE_CACHE', FALSE);



    //------------------------------------------------------------------------------------------
    //  BANDWIDTH SETTINGS
    //
    //  these settings are only needed when using bandwidth limiting.
    //  
    //  bandwidth is limited my sending a limited amount of video data(XMOOV_BW_PACKET_SIZE),
    //  in specified time intervals(XMOOV_BW_PACKET_INTERVAL). 
    //  avoid time intervals over 1.5 seconds for best results.
    //  
    //  you can also control bandwidth limiting via http command using your video player.
    //  the function getBandwidthLimit($part) holds three preconfigured presets(low, mid, high),
    //  which can be changed to meet your needs
    //------------------------------------------------------------------------------------------    

    //set how many kilobytes will be sent per time interval
    define('XMOOV_BW_PACKET_SIZE', 90);

    //set the time interval in which data packets will be sent in seconds.
    define('XMOOV_BW_PACKET_INTERVAL', 0.3);

    //set to TRUE to control bandwidth externally via http.
    define('XMOOV_CONF_ALLOW_DYNAMIC_BANDWIDTH', TRUE);



    //------------------------------------------------------------------------------------------
    //  DYNAMIC BANDWIDTH CONTROL
    //------------------------------------------------------------------------------------------

    function getBandwidthLimit($part)
    {
        switch($part)
        {
            case 'interval' :
                switch($_GET[XMOOV_GET_BANDWIDTH])
                {
                    case 'low' :
                        return 1;
                    break;
                    case 'mid' :
                        return 0.5;
                    break;
                    case 'high' :
                        return 0.3;
                    break;
                    default :
                        return XMOOV_BW_PACKET_INTERVAL;
                    break;
                }
            break;
            case 'size' :
                switch($_GET[XMOOV_GET_BANDWIDTH])
                {
                    case 'low' :
                        return 10;
                    break;
                    case 'mid' :
                        return 40;
                    break;
                    case 'high' :
                        return 90;
                    break;
                    default :
                        return XMOOV_BW_PACKET_SIZE;
                    break;
                }
            break;
        }
    }



    //------------------------------------------------------------------------------------------
    //  INCOMING GET VARIABLES CONFIGURATION
    //  
    //  use these settings to configure how video files, seek position and bandwidth settings are accessed by your player
    //------------------------------------------------------------------------------------------

    define('XMOOV_GET_FILE', 'file');
    define('XMOOV_GET_POSITION', 'position');
    define('XMOOV_GET_AUTHENTICATION', 'key');
    define('XMOOV_GET_BANDWIDTH', 'bw');



    //  END SCRIPT CONFIGURATION - do not change anything beyond this point if you do not know what you are doing



    //------------------------------------------------------------------------------------------
    //  PROCESS FILE REQUEST
    //------------------------------------------------------------------------------------------

    if(isset($_GET[XMOOV_GET_FILE]) && isset($_GET[XMOOV_GET_POSITION]))
    {
        //  PROCESS VARIABLES

        # get seek position
        $seekPos = intval($_GET[XMOOV_GET_POSITION]);
        # get file name
        $fileName = htmlspecialchars($_GET[XMOOV_GET_FILE]);
        # assemble file path
        $file = XMOOV_PATH_ROOT . XMOOV_PATH_FILES . $fileName;

        # assemble packet interval
        $packet_interval = (XMOOV_CONF_ALLOW_DYNAMIC_BANDWIDTH && isset($_GET[XMOOV_GET_BANDWIDTH])) ? getBandwidthLimit('interval') : XMOOV_BW_PACKET_INTERVAL;
        # assemble packet size
        $packet_size = ((XMOOV_CONF_ALLOW_DYNAMIC_BANDWIDTH && isset($_GET[XMOOV_GET_BANDWIDTH])) ? getBandwidthLimit('size') : XMOOV_BW_PACKET_SIZE) * 1042;

        # security improved by by TRUI www.trui.net
        if (!file_exists($file))
        {
            print('<b>ERROR:</b> xmoov-php could not find (' . $fileName . ') please check your settings.'); 
            exit();
        }
        if(file_exists($file) && strrchr($fileName, '.') == '.flv' && strlen($fileName) > 2 && !eregi(basename($_SERVER['PHP_SELF']), $fileName) && ereg('^[^./][^/]*$', $fileName))
        {
            # stay clean
            @ob_end_clean();
            @set_time_limit(0);

            # keep binary data safe
            set_magic_quotes_runtime(0);

            $fh = fopen($file, 'rb') or die ('<b>ERROR:</b> xmoov-php could not open (' . $fileName . ')');

            $fileSize = filesize($file) - (($seekPos > 0) ? $seekPos  + 1 : 0);

            //  SEND HEADERS
            if(!XMOOV_CONF_ALLOW_FILE_CACHE)
            {
                # prohibit caching (different methods for different clients)
                session_cache_limiter("nocache");
                header("Expires: Thu, 19 Nov 1981 08:52:00 GMT");
                header("Last-Modified: " . gmdate("D, d M Y H:i:s") . " GMT");
                header("Cache-Control: no-store, no-cache, must-revalidate, post-check=0, pre-check=0");
                header("Pragma: no-cache");
            }

            # content headers
            header("Content-Type: video/x-flv");
            header("Content-Disposition: attachment; filename=\"" . $fileName . "\"");
            header("Content-Length: " . $fileSize);

            # FLV file format header
            if($seekPos != 0) 
            {
                print('FLV');
                print(pack('C', 1));
                print(pack('C', 1));
                print(pack('N', 9));
                print(pack('N', 9));
            }

            # seek to requested file position
            fseek($fh, $seekPos);

            # output file
            while(!feof($fh)) 
            {
                # use bandwidth limiting - by Terry
                if(XMOOV_CONF_LIMIT_BANDWIDTH)
                {
                    # get start time
                    list($usec, $sec) = explode(' ', microtime());
                    $time_start = ((float)$usec + (float)$sec);
                    # output packet
                    print(fread($fh, $packet_size));
                    # get end time
                    list($usec, $sec) = explode(' ', microtime());
                    $time_stop = ((float)$usec + (float)$sec);
                    # wait if output is slower than $packet_interval
                    $time_difference = $time_stop - $time_start;

                    # clean up
                    @flush();
                    @ob_flush();

                    if($time_difference < (float)$packet_interval)
                    {
                        usleep((float)$packet_interval * 1000000 - (float)$time_difference * 1000000);
                    }
                }
                else
                {
                    # output file without bandwidth limiting
                    print(fread($fh, filesize($file))); 
                }
            }

        }

    }
?>