User-agent: * 
Disallow: /themes/
Disallow: /images/

User-agent: LinkChecker/4.9
Disallow: /images/

User-agent: Googlebot-Image
Disallow: /images/

User-agent: Googlebot
Disallow: /*.gif$
Disallow: /*.png$
Disallow: /*.ai$
Disallow: /*.jpg$
Disallow: /*.psd$
Disallow: /*.eps$