Install opencv-2.4.9 + opencl1.2 AMD Radeon

gentoo

manual install

rm /usr/lib64/OpenCL/vendors/amd/* /usr/lib32/OpenCL/vendors/amd/* /usr/include/CL/* 
rm /usr/lib/libOpenCL.so* /usr/lib64/libOpenCL.so*  /usr/lib32/libOpenCL.so*
tar zxf AMD-APP-SDK-v2.9-lnx64.tgz
sh Install-AMD-APP.sh
tar zxf clAmdFft-1.10.321.tar.gz
sh install-clAmdFft-1.10.321.sh
tar zxf clAmdBlas-1.10.321.tar.gz
sh install-clAmdBlas-1.10.321.sh
ln -s /opt/AMDAPP/include/CL/* /usr/include/CL/
echo "media-libs/opencv opencl" >> /etc/portage/package.use
echo "media-libs/opencv ~amd64" >> /etc/portage/package.keywords

Install opencv using ebuild https://github.com/niitsuma/niitsuma-overlay/tree/master/media-libs/opencv

emerge -av ati-drivers
rm /usr/include/CL/*
ln -s /opt/AMDAPP/include/CL/* /usr/include/CL/
ln -s /opt/AMDAPP/include/CL /usr/local/include/
memo

most inportant part is https://github.com/niitsuma/niitsuma-overlay/blob/master/media-libs/opencv/files/opencv-2.4.9-detectopencl.patch
Maybe this patch works for other linux dist

install using ebuild https://github.com/niitsuma/niitsuma-overlay

echo ">=media-libs/opencv-2.4.10" >> /etc/portage/package.mask
echo ">=x11-drivers/ati-drivers-14.12:1" >> /etc/portage/package.mask
echo ">=sys-devel/gcc-4.8" >> /etc/portage/package.mask

emergs -av x11-drivers/ati-drivers
emerge -av dev-util/amdapp dev-util/clamdblas  dev-util/clamdfft
emerge -av opencv
etc-update
emergs -av x11-drivers/ati-drivers

Ref