디자인원엑스 썸네일 오류

Fatal error: Call to undefined function thumbnail() in C:\APM_Setup\htdocs\gnuboard3\skin\latest\8\latest.skin.php on line 122
디자인 원엑스의 최신글 스킨을 사용중에 위와같은 오류가 발생하면 어떻게 고쳐줘야하나요?
필요한 파일이나 찾지 못한 부분이 있다면 가르쳐주세요
<?
if (!defined("_GNUBOARD_")) exit; // 개별 페이지 접근 불가

/*
* ez_cineV_Gallery Gnuboard4
*
* latest.skin.php
*
* Copyright 2011 Man Hyung, cho
*
* File encoding: Korean(Euc-kr)
*
*/



$is_crop = 1;
// $is_crop : 세로 높이가 $height를 넘을 때 crop 할 것인지를 결정
// 0 : crop 하지 않습니다
// 1 : 기본 crop
// 2 : 중간을 기준으로 crop


//불당썸---------------------------------------------------------------//
$img_width = 189; //표시할 이미지의 가로사이즈
$img_height = 189; //표시할 이미지의 세로사이즈




//언샾마스트 퀄리티(썸 노이즈바지)
$filter[type] = 99;
$filter[arg1] = 100;
$filter[arg2] = 1;
$filter[arg3] = 2;


$data_path = $g4[path]."/data/file/$bo_table";
$thumb_path = $data_path.'/thumb';
$no_img = $latest_skin_path."/img/no_img.gif";

// 불당썸을 include
include_once("$g4[path]/lib/thumb.lib.php");
//불당썸---------------------------------------------------------------//

//$list_content = "450"; //내용길이
$cols = 6;


?>
<? include_once("$g4[path]/YouChangWha.lib.php"); ?>
<style type="text/css" media="screen">

.thumbnailWrapper { width:100%; margin:0px auto; } /* not important */

.thumbnailWrapper ul {
list-style-type: none; /* remove the default style for list items (the circles) */
margin:0px; /* remove default margin */
padding:0px; /* remove default padding */
}
.thumbnailWrapper ul li {
float:left; /* important: left float */
position:relative; /* so we can use top and left positioning */
overflow:hidden; /* hide the content outside the boundaries (ZOOM) */
}
.thumbnailWrapper ul li a img {
width:200px; /* not important, the pics we use here are too big */
position:relative; /* so we can use top and left positioning */
border:none; /* remove the default blue border */
}
.caption{
position:absolute; /* needed for positioning */
bottom:0px; /* bottom of the list item (container) */
left:0px; /* start from left of the list item (container) */
width:100%; /* stretch to the whole width of container */
display:none; /* hide by default */
/* styling bellow */
background:#0c4b62;
color:white;
opacity:0.9;
}
.caption .captionInside{
/* just styling */
padding:10px;
margin:0px;
color:#FFF;
}
.clear { clear:both; } /* to clear the float after the last item */a{ color:#FFCC00;}
</style>




<? /*
<table width="100%" border="0" cellspacing="0" cellpadding="8" style="border-bottom:1px solid #999; border-top:1px solid #999;">
<tr>
<td><strong><a href='<?=$g4[bbs_path]?>/board.php?bo_table=<?=$bo_table?>'><?=$board[bo_subject]?></a></strong></td>
<td align="right"><a href='<?=$g4[bbs_path]?>/board.php?bo_table=<?=$bo_table?>'>+ 더보기</a></td>
</tr>
</table>

<br />

*/ ?>
<div class='thumbnailWrapper'>
<!-- start unordered list -->
<ul>
<?
$ch_num = "0";
for ($i=0; $i<count($list); $i++) { ?>

<? //리스트 페이지 이미지 출력

//썸네일 생성
$thumfile = "";
$thumb = $thumb_path.'/'.$list[$i][wr_id];

$file = $list[$i][file][0][path] .'/'. $list[$i][file][0][file];

// 업로드된 파일이 이미지라면
if (preg_match("/\.(jpg|gif|png|bmp)$/i", $file) && file_exists($file)) {
/*여기 122줄*/ $thumb = thumbnail($file, $img_width, $img_height, 0, 1, 90, 0, "", $filter, $noimg); //첨부파일 언샾마스크추가

} else { //에디터에서 삽입한 이미지
$edit_img = $list[$i]['wr_content'];
if (eregi("data/cheditor4[^<>]*\.(gif|jp[e]?g|png|bmp)", $edit_img, $tmp)) { // data/cheditor------
$file = $g4[path].'/' . $tmp[0]; // 파일명

$thumb=thumbnail($file, $img_width, $img_height, 0, $is_crop, 90, 0, "", $filter, $noimg); //언샾마스크추가

}
}
if ($i>0 && $i%$cols==0) {
//echo "<tr><td colspan='$cols'></td><tr>";
}

$wr_content = preg_replace("/<(.*?)\>/"," ",$list[$i][wr_content]);
$wr_content = preg_replace("/&nbsp;/"," ",$wr_content);
$wr_content = str_replace("//##", " ", $wr_content);
$wr_content1 = cut_str(get_text($wr_content), 100, '…');

$wr_subject = $list[$i][wr_subject];
$wr_subject1 = cut_str(get_text($wr_content), 30, '…');



if (preg_match("/\.(jpg|gif|png|bmp)$/i", $thumb) && file_exists($thumb)) {
$ch_num++;
//echo '<div class="item">';
echo "<li>";
echo "<a href='{$list[$i]['href']}' class='pos$ch_num'>";
echo "<img src='$thumb' border='0'>";
echo "</a>";
echo "<div class='caption'>
<p class='captionInside'>".$list[$i][wr_subject]."</p>
</div>";
echo "</li>";
//echo "<div class='caption'> <a href='$list[$i]['href']}'>$wr_subject1</a>
//<p>$wr_content1</p>
//</div>";
//echo "</div>";




}


} ?>
<? if (count($list) == 0) { echo "<table width='100%' border='0' cellpadding='0' cellspacing='0'><tr><td colspan=3 align=center height=100>자료가 없습니다.</td></tr></table>"; } ?>

</ul>
</div>
<!-- The JavaScript -->

<script type="text/javascript" charset="euc-kr">
$(window).load(function(){

//set and get some variables
var thumbnail = {
imgIncrease : 100, /* the image increase in pixels (for zoom) */
effectDuration : 400, /* the duration of the effect (zoom and caption) */
/*
get the width and height of the images. Going to use those
for 2 things:
make the list items same size
get the images back to normal after the zoom
*/
imgWidth : $('.thumbnailWrapper ul li').find('img').width(),
imgHeight : $('.thumbnailWrapper ul li').find('img').height()

};

//make the list items same size as the images
$('.thumbnailWrapper ul li').css({

'width' : thumbnail.imgWidth,
'height' : thumbnail.imgHeight

});

//when mouse over the list item...
$('.thumbnailWrapper ul li').hover(function(){

$(this).find('img').stop().animate({

/* increase the image width for the zoom effect*/
width: parseInt(thumbnail.imgWidth) + thumbnail.imgIncrease,
/* we need to change the left and top position in order to
have the zoom effect, so we are moving them to a negative
position of the half of the imgIncrease */
left: thumbnail.imgIncrease/2*(-1),
top: thumbnail.imgIncrease/2*(-1)

},{

"duration": thumbnail.effectDuration,
"queue": false

});

//show the caption using slideDown event
$(this).find('.caption:not(:animated)').slideDown(thumbnail.effectDuration);

//when mouse leave...
}, function(){

//find the image and animate it...
$(this).find('img').animate({

/* get it back to original size (zoom out) */
width: thumbnail.imgWidth,
/* get left and top positions back to normal */
left: 0,
top: 0

}, thumbnail.effectDuration);

//hide the caption using slideUp event
$(this).find('.caption').slideUp(thumbnail.effectDuration);

});

});
</script>