For openSUSE Tumbleweed run the following as root:
zypper addrepo https://download.opensuse.org/repositories/home:Aikhjarto:branches:openSUSE:Factory/openSUSE_Tumbleweed/home:Aikhjarto:branches:openSUSE:Factory.repo
zypper refresh
zypper install libraw
For 16.0 run the following as root:
zypper addrepo https://download.opensuse.org/repositories/home:Aikhjarto:branches:openSUSE:Factory/16.0/home:Aikhjarto:branches:openSUSE:Factory.repo
zypper refresh
zypper install libraw
For 15.6 run the following as root:
zypper addrepo https://download.opensuse.org/repositories/home:Aikhjarto:branches:openSUSE:Factory/15.6/home:Aikhjarto:branches:openSUSE:Factory.repo
zypper refresh
zypper install libraw