Converting htaccess to nginx

Trying to setting an image server, I put them on nginx for speed. I'm rewriting a lot of the code but the previous developer left it in shambles. Can someone g开发者_运维技巧ive me a nudge in the right direction on converting this to nginx?

<IfModule mod_rewrite.c>
    RewriteEngine On
    RewriteBase /art_preview/
    RewriteCond %{REQUEST_FILENAME} !-f
    RewriteCond %{REQUEST_FILENAME} !-d
    RewriteRule ^art_preview/(.*)_(.*)_(.*)_(.*)_(.*)_(.*).jpg$ /imagetest.php?image_code=$1&frame_code=$2&matte_code=$3&style=$4&width=$5&max_size=$6 [L]
    RewriteRule ^art_preview/([a-zA-Z0-9]{1,})_(\d{1,}).jpg$ /imagetest.php?image_code=$1&max_size=$2 [L]
</IfModule>

You can try this Online Converter. It seems to be in beta, but it might get you on the right track.