[CentOS] Custom ISO based on kickstart

Hello!

I would like to shrink my installation media restricted only to
necessary packages based on my kickstart file. So I am looking for an
application/script which select rpms and those dependencies based on a
kickstart file. If just display them that is ok does not need to
copy/download anything else. Is there any such utility?

I've found a site which helps to select rpms based on my comps.xml
(mandatory, default) but I do not want to change my comps.xml but want
to create a kickstart file and create a media based on that.

Thanks,
a