Fatal error: Uncaught Error: Call to undefined function imagecreatefrompng() in /home/public_html/www/bgsseye/lib/thumbnail.lib.php:303 Stack trace: #0 /home/public_html/www/bgsseye/lib/thumbnail.lib.php(190): thumbnail('237252212_YkKfA...', '/home/public_ht...', '/home/public_ht...', '835', 597, false) #1 /home/public_html/www/bgsseye/lib/thumbnail.lib.php(91): get_view_thumbnail('<a href="http:/...') #2 /home/public_html/www/bgsseye/skin/board/basic/view.skin.php(97): get_file_thumbnail(Array) #3 /home/public_html/www/bgsseye/bbs/view.php(143): include_once('/home/public_ht...') #4 /home/public_html/www/bgsseye/bbs/board.php(236): include_once('/home/public_ht...') #5 {main} thrown in /home/public_html/www/bgsseye/lib/thumbnail.lib.php on line 303

게시판에 820px 이미지를 올리면 괜찮은데.. 850px 이미지를 올리면 위와 같은 에러가 발생합니다.

http://133.186.222.135/bgsseye/bbs/board.php?bo_table=NoticeTeam02&wr_id=3

해당 오류가 신버전에서 발생하는 에러인지 궁금합니다.