How to insert custom value in the script

all,
I have this script: (I’m sorry I’m putting it all here, but I’m not sure what’s important)
[php]

<?php
add_action('the_content','rpf_content_filter');
add_filter('wp_head', 'rpf_init');
$rpf_options = get_option('rpf_options');

function rpf_content_filter($content){
    if(is_admin())
        return $content;

    $id = get_post_meta(get_the_ID(), 'rpf_feed_id', true);

    if(!$id)
        return $content;//might be normal content

    global $rpf_options;
    if($rpf_options['word_limit'] >0 )
        $content = rpf_truncate($content, $rpf_options['word_limit']);


    $sourcelink=get_post_meta(get_the_ID(), 'rpf_sourcepermalink', true);

    if($sourcelink)
        $link='<p>'.rpf_custom_template($sourcelink,$id).'</p>';

    $content=$content.$link;

    return $content;


}

function rpf_custom_template($sourcelink,$feed_id){



    global $rpf_options;
    $custom_template = $rpf_options['custom_template'];

    if( false ===  strpos($custom_template, '%SOURCE_URL%' ) )
        $custom_template .= ' <a href="%SOURCE_URL%">%SOURCE_URL%</a> ';



    $feed = rpf_get_feed($feed_id);

    $user = get_userdata($feed['author']);
    $author = $user->nickname;

    $category = get_cat_name($feed['category']);

    $feed_url = $feed['url'];

    $feed_name = $feed['name'];

    $custom_template = str_replace(
        array('%SOURCE_URL%','%AUTHOR%','%CATEGORY%','%FEED_URL%','%FEED_NAME%'),
        array($sourcelink,$author,$category,$feed_url,$feed_name),
        $custom_template

    );

    return $custom_template;


}
function rpf_truncate($text,$count) { 
    $count=intval($count);
    if(  $count<1 || substr_count($text,' ') < $count )
        return $text;

    $temp = explode(' ', $text);

    $text = implode(' ', array_slice($temp, 0, $count));

    return $text;

}
function rpf_init(){

    global $rpf_options;

    $now_time=time();

    $interval=60*60*3;
    $lastactive=$rpf_options['lastactive'];
    if(!$lastactive){
        $lastactive=$now_time;
        $rpf_options['lastactive']=$lastactive;
        update_option('rpf_options', $rpf_options);

    }

    if ( ($now_time - $lastactive ) >= $interval ) {

        $rpf_options['lastactive'] = $now_time+$interval;
        update_option('rpf_options', $rpf_options);
        rpf_process_feeds();
    }

}



function rpf_process_feeds(){

    @set_time_limit(0);


    $feeds=rpf_get_feeds();
    if($feeds){

        rpf_log("<b>----------Processing all feeds-------------</b>");
        foreach($feeds as $feed){

            rpf_process_feed($feed);

        }
    }else{

        rpf_log("No feeds data found!");
    }


}


function rpf_process_feed($feed){
    @set_time_limit(0);
    if(empty($feed['url'])){

        return false;
    }


    rpf_log("Processing feed <b>{$feed['url']}</b>");

    $lastactive = $feed['lastactive'];

    $now=time();

    $frequency = $feed['frequency']*60*60;

    if( ($now - $lastactive) >= $frequency ){

        rpf_update_feed_lastactive($feed['id'],$now);

    }else{

        rpf_log("It's not the time to update <b>{$feed['url']}</b>. <a href='http://www.wprssposter.com/faq.html#cronjob'>Explanation</a>");
        return false;
    }

    global $rpf_options;

    $max_items=$feed['max_items'];

    if(empty($max_items)||!is_numeric($max_items))

        $max_items=3;

    $simplepie = rpf_fetch_feed($feed['url'],$max_items);
    $error=$simplepie->error();

    if($error){

        rpf_log("Feed Error: <b>$error</b>");
        return false;
    }

        $count = 0;

    foreach($simplepie->get_items() as $item){
        if( rpf_is_duplicate(  $item->get_title() ) ){
                rpf_log('Filtering duplicate post');
                continue;
        }
        if(false == rpf_process_item($item,$feed))
            continue;
        $count++;
        if($count == $max_items)
            break;
        }

        if($count==0)
        rpf_log("No new or qualified post for <b>{$feed['url']}</b> <a href='http://www.wprssposter.com/faq.html#newandqualified'>Explanation</a>");
    else
        rpf_log( "Fetch $count posts from <b>{$feed['url']}</b>" );


        return true;


}
function rpf_process_item($item,$feed){


    global $wpdb;

    $title = $item->get_title();

    $link = $item->get_permalink();

    if(false !== strpos($link,'news.google.com')){
        $link=urldecode(substr($link,strpos($link,'url=')+4));
    }elseif(false !== strpos($link,'/**')){
        $link=urldecode(substr($link,strpos($link,'/**')+3));

    }   

    $content = rpf_full_feed($link);

    if(!$content ){
        //rpf_log("Cannot grab full content from <b>$link</b>");
        return false;
    }
    $title=rpf_title_fix($title);

    $content=rpf_content_fix($content);

    if(empty($title)||empty($content)){

        return false;
    }

    $content=rpf_parse_images($content,$item->get_base());
    $meta = array(
         'rpf_feed_id' => $feed['id'],
         'rpf_sourcepermalink' => $link,

        );

    $rpf_date = date("Y-m-d H:i:s", time());
    if($feed['publish_date'] === 'Publish Immediately'){

    }elseif($feed['publish_date'] === 'RSS Publication Date'){

        $rpf_date = $item->get_date("Y-m-d H:i:s");
    }



    rpf_insert_post( $title,$content,$feed['category'],$feed['tags'],$meta,$feed['post_status'],$rpf_date,$feed['author']);
    rpf_log("<b>{$title}</b> added");
    global $wpdb;
    global $rpf_options;
    $hash=rpf_item_hash($item->get_title());
    $sql="insert into {$rpf_options['db']['post']} (hash) values ('{$hash}')";
    $wpdb->query($sql);

    return true;


}
function rpf_title_fix($title){
    if($title && strpos($title,' - ')){

        $backup=$title;
        $backup=preg_replace('/([-])/','$1[D]',$backup);

        $backup=explode('[D]',$backup);

        if( strlen($backup[0])>10 || count($backup)>=2 )
            unset($backup[count($backup)-1]);
        else
            return $title;

        $title=trim(implode('',$backup),' - ');
    }
    return $title;

}

function rpf_content_fix($text){
    preg_match_all('@(<a.+?href=".+?">)(.*?</a>)@',$text,$m);
    $urls = $m[1];
    if(count($urls)){
        foreach($urls as $pos => $link){
            if(false === stripos($link,'http://') && false === stripos($link,'https://')){

                $text=str_replace($link,'',$text);

                $text=str_replace($m[2][$pos],str_replace('</a>','',$m[2][$pos]),$text);
            }
        }
    }
    $text=preg_replace("/[&|#|&#]+[a-z0-9]+;/i","",$text);
    $text=preg_replace('@<[dtrx][^>]*>@','',$text);
    $text=preg_replace('@</[dtrx][^>]*>@','',$text);
    return $text;

}
function rpf_parse_images($content,$link){

    preg_match_all('/<img(.+?)src="(.+?)"(.*?)>/', $content, $images);
    $urls = $images[2];

        if(count($urls)){

        foreach($urls as $pos => $url){
            $oldurl=$url;
            $meta=parse_url($url);

            if(!isset($meta['host'])){

                $meta=parse_url($link);
                $url=$meta['scheme'].'://'.$meta['host'].'/'.$url;

            }

                $newurl = rpf_cache_image($url);
                if($newurl)
                        $content = str_replace($oldurl, $newurl, $content);
            else
                $content = str_replace($images[0][$pos],'',$content);
            } 
        }
    return $content;



}
function rpf_cache_image($url){
    if( strpos($url, "icon_") !== FALSE)
          return false;
    global $rpf_options;
    $contents = rpf_get_file($url);

    if( !$contents )
        return false;
    $basename = basename($url);
    $paresed_url = parse_url($basename);

    $filename = substr(md5(time()), 0, 5) . '_' . $paresed_url['path'];

    $cachepath = RPF_CACHE;
    $pluginpath = RPF_URL_ROOT;
        $real_cachepath=dirname(__FILE__).'/'.$cachepath;
    if(is_writable( $real_cachepath ) ){

        if($contents){

            file_put_contents($real_cachepath . $filename, $contents);
            $i=@exif_imagetype($real_cachepath . $filename);
            if($i)
                return $pluginpath . $cachepath . rawurlencode($filename);
        }
    }else{

        rpf_log($real_cachepath . " directory is not writable" );

    }

    return false;

}
function rpf_insert_post($title,$content,$category=array(1),$tags_input='',$meta='',$post_status='publish',$rpf_date,$post_author=1){


    $category=(array)$category;

    if(!$rpf_date)
        $rpf_date = time();


    $postid = wp_insert_post(array(
            'post_title'              => $title,
        'post_content'        => $content,
        'post_category'           => $category,
        'tags_input'          => $tags_input,
        'post_status'         => $post_status,
        'post_author'             => $post_author,
        "post_date"           => get_date_from_gmt($rpf_date),
        ));
    if($meta)
        foreach($meta as $key => $value) 
            rpf_insert_post_meta($postid, $key, $value);


    return $postid;

}

function rpf_full_feed($permalink){

    require_once(RPFINC.'readability.php');

    if ($permalink && $html = rpf_get_file($permalink)) {

        $html = rpf_convert_to_utf8($html);

        $content = grabArticleHtml($html);


    }else
        return false;

    if( false !== stripos($content,'readability was unable to parse this page for content') )
        return false;
    if( false !== stripos($content, 'return go_back();') )
        return false;

    return $content;

}
function rpf_insert_post_meta($postid, $key, $value) {
    global $wpdb;

    $result = $wpdb->query( "INSERT INTO $wpdb->postmeta (post_id,meta_key,meta_value ) " 
                                    . " VALUES ('$postid','$key','$value') ");

    return $wpdb->insert_id;        
}

function rpf_is_duplicate($title){

    global $wpdb;
    global $rpf_options;

    $hash = rpf_item_hash($title);

    $row = $wpdb->get_row("SELECT * FROM {$rpf_options['db']['post']} "
                          . "WHERE hash = '{$hash}'");  
    if($row)
        return true;
    return false;


}

function rpf_item_hash($data){

    return sha1($data);
}
function rpf_get_file($url){

    if(ini_get('allow_url_fopen') != 1) {
        @ini_set('allow_url_fopen', '1');
    }

    if(ini_get('allow_url_fopen') != 1) {

        $ch = curl_init();

        curl_setopt($ch, CURLOPT_FOLLOWLOCATION, true);
        curl_setopt($ch, CURLOPT_RETURNTRANSFER, true); //Set curl to return the data instead of printing it to the browser.
        curl_setopt($ch, CURLOPT_URL, $url);

        $data = curl_exec($ch);
        curl_close($ch);

        return $data;


    } else {
        return @file_get_contents($url);
    }

    return false;


}
function rpf_fetch_feed($url,$max_items){

    $url=str_replace(' ','+',$url);

     # SimplePie
    if(! class_exists('SimplePie'))
      require_once( RPFINC . 'simplepie.class.php' );

    $feed = new SimplePie();
    $feed->enable_order_by_date(false); 
    $feed->set_feed_url($url);
    $feed->set_item_limit($max_items);
    $feed->set_stupidly_fast(true);
    $feed->enable_cache(false);    
    $feed->init();
    $feed->handle_content_type(); 

    return $feed;

}

function rpf_get_feeds(){

    $rtn_feeds=array();
    global $rpf_options;

    $feeds=$rpf_options['feed'];

    foreach($feeds as $feed){


        $rtn_feeds[]=$feed;

    }
    return $rtn_feeds;


}

function rpf_get_feed($id){

    $feeds=rpf_get_feeds();

    foreach($feeds as $feed){

        if($feed['id'] == $id)      
            return $feed;

    }
    return false;


}

function rpf_update_feed($_feed){

    global $rpf_options;

    $feeds=$rpf_options['feed'];


    foreach($_feed as $k => $v)
        $_feed[$k]=str_replace('','',$v);

    foreach($feeds as $key => $feed){

        if($feed['id'] == $_feed['id']){

            if(empty($_feed['name'])||empty($_feed['url'])){

                unset($feeds[$key]);
                $feeds[]=array(
                'id' => $_feed['id'],
                'name' => '',
                'url' => '',
                'category' => 1,
                'tags' =>'',
                'frequency' => 8,
                'max_items' => 3,
                'lastactive' =>'0',
                'post_status' => 'publish',
                'publish_date' => 'Publish Immediately',
                'author' => 1
                );
                break;      

            }else{
                if($_feed['url'] == $feed['url'] && $_feed['name'] == $feed['name'])
                    $_feed['lastactive']=$feed['lastactive'];
                else
                    $_feed['lastactive']='0';

                unset($feeds[$key]);
                $feeds[$key]=$_feed;
                break;
            }

        }   


    }
    $rpf_options['feed']=$feeds;
    update_option('rpf_options',$rpf_options);

}
function rpf_update_feed_lastactive($id,$lastactive){

    global $rpf_options;

    $feeds=$rpf_options['feed'];

    foreach($feeds as $key => $feed){

        if($feed['id'] == $id){
            $backup=$feed;
            unset($feeds[$key]);
            $backup['lastactive']=$lastactive;
            $feeds[$key]=$backup;
            break;

        }   


    }
    $rpf_options['feed']=$feeds;
    update_option('rpf_options',$rpf_options);

}


function rpf_log($message){
    global $wpdb;
        global $rpf_options;
        $message = $wpdb->escape($message);
        $time = current_time('mysql', true);
        $wpdb->query("INSERT INTO {$rpf_options['db']['log']} (message, created_on) VALUES ('{$message}', '{$time}') "); 

}
function rpf_get_logs($page,$logs_per_page){
    global $wpdb;
    global $rpf_options;


    if($page == 0) $page = 1;
    $page--;
    $orderby = "created_on";
    $ordertype = 'ASC';
    $start = $page * $logs_per_page;
    $end = $start + $logs_per_page;
    $limit = "LIMIT {$start}, {$end}";


    return $wpdb->get_results("SELECT * FROM {$rpf_options['db']['log']} ORDER BY $orderby $ordertype $limit");
}
function rpf_timezone_mysql($format, $time){
    return mysql2date($format, $time);    
}
//////////////////////////////////////////////
// Convert $html to UTF8
// (uses HTTP headers and HTML to find encoding)
// adapted from http://stackoverflow.com/questions/910793/php-detect-encoding-and-make-everything-utf-8
//////////////////////////////////////////////
function rpf_convert_to_utf8($html, $header=null)
{
    $accept = array(
        'type' => array('application/rss+xml', 'application/xml', 'application/rdf+xml', 'text/xml', 'text/html'),
        'charset' => array_diff(mb_list_encodings(), array('pass', 'auto', 'wchar', 'byte2be', 'byte2le', 'byte4be', 'byte4le', 'BASE64', 'UUENCODE', 'HTML-ENTITIES', 'Quoted-Printable', '7bit', '8bit'))
    );
    $encoding = null;
    if ($html || $header) {
        if (is_array($header)) $header = implode("n", $header);
        if (!$header || !preg_match_all('/^Content-Type:s+([^;]+)(?:;s*charset=([^;"'n]*))?/im', $header, $match, PREG_SET_ORDER)) {
            // error parsing the response
        } else {
            $match = end($match); // get last matched element (in case of redirects)
            if (!in_array(strtolower($match[1]), $accept['type'])) {
                // type not accepted
                // TODO: avoid conversion
            }
            if (isset($match[2])) $encoding = trim($match[2], '"'');
        }
        if (!$encoding) {
            if (preg_match('/^<?xmls+version=(?:"[^"]*"|'[^']*')s+encoding=("[^"]*"|'[^']*')/s', $html, $match)) {
                $encoding = trim($match[1], '"'');
            } elseif(preg_match('/<metas+http-equiv=["']Content-Type["'] content=["'][^;]+;s*charset=([^;"'>]+)/i', $html, $match)) {
                if (isset($match[1])) $encoding = trim($match[1]);
            }
        }
        if (!$encoding) {
            $encoding = 'utf-8';
        } else {
            if (!in_array($encoding, array_map('strtolower', $accept['charset']))) {
                // encoding not accepted
                // TODO: avoid conversion
            }
            if (strtolower($encoding) != 'utf-8') {
                if (strtolower($encoding) == 'iso-8859-1') {
                    // replace MS Word smart qutoes
                    $trans = array();
                    $trans[chr(130)] = '&sbquo;';    // Single Low-9 Quotation Mark
                    $trans[chr(131)] = '&fnof;';    // Latin Small Letter F With Hook
                    $trans[chr(132)] = '&bdquo;';    // Double Low-9 Quotation Mark
                    $trans[chr(133)] = '&hellip;';    // Horizontal Ellipsis
                    $trans[chr(134)] = '&dagger;';    // Dagger
                    $trans[chr(135)] = '&Dagger;';    // Double Dagger
                    $trans[chr(136)] = '&circ;';    // Modifier Letter Circumflex Accent
                    $trans[chr(137)] = '&permil;';    // Per Mille Sign
                    $trans[chr(138)] = '&Scaron;';    // Latin Capital Letter S With Caron
                    $trans[chr(139)] = '&lsaquo;';    // Single Left-Pointing Angle Quotation Mark
                    $trans[chr(140)] = '&OElig;';    // Latin Capital Ligature OE
                    $trans[chr(145)] = '&lsquo;';    // Left Single Quotation Mark
                    $trans[chr(146)] = '&rsquo;';    // Right Single Quotation Mark
                    $trans[chr(147)] = '&ldquo;';    // Left Double Quotation Mark
                    $trans[chr(148)] = '&rdquo;';    // Right Double Quotation Mark
                    $trans[chr(149)] = '&bull;';    // Bullet
                    $trans[chr(150)] = '&ndash;';    // En Dash
                    $trans[chr(151)] = '&mdash;';    // Em Dash
                    $trans[chr(152)] = '&tilde;';    // Small Tilde
                    $trans[chr(153)] = '&trade;';    // Trade Mark Sign
                    $trans[chr(154)] = '&scaron;';    // Latin Small Letter S With Caron
                    $trans[chr(155)] = '&rsaquo;';    // Single Right-Pointing Angle Quotation Mark
                    $trans[chr(156)] = '&oelig;';    // Latin Small Ligature OE
                    $trans[chr(159)] = '&Yuml;';    // Latin Capital Letter Y With Diaeresis
                    $html = strtr($html, $trans);
                }
                if(!class_exists('SimplePie_Misc'))
                    require_once(RPFINC.'simplepie.class.php');

                $html = SimplePie_Misc::change_encoding($html, $encoding, 'utf-8');

                /*
                if (function_exists('iconv')) {
                    // iconv appears to handle certain character encodings better than mb_convert_encoding
                    $html = iconv($encoding, 'utf-8', $html);
                } else {
                    $html = mb_convert_encoding($html, 'utf-8', $encoding);
                }
                */
            }
        }
    }
    return $html;
}
if ( ! function_exists( 'exif_imagetype' ) ) {
    function exif_imagetype ( $filename ) {
        return @getimagesize( $filename );
    }
}
?>

[/php]
So in line 229 I want to define one more value like this:
[php]

$content=rpf_parse_images($content,$item->get_base());
    $meta = array(
         'rpf_feed_id' => $feed['id'],
         'rpf_sourcepermalink' => $link,
         [u][b]'preview'[/b][/u] =>

[/php]
I did it and it works, but the problem is that I want to insert here an already existing value – from line 337 – variable $real_cachepath from function rpf_cache_image. I have tried to define it directly, but it doesn’t work.
Can you help me, please