I want to use opencv in webOS but I don't know how to install. is it same as other raspberry pi OS???
What do you mean the installation.
as following a path below:
opencv is already ready to use.
To build opencv in webOS OSE, you need to change somethings like "remove blacklist in meta-webos/conf/distro/include/webos-recipe-blacklist-world.inc". I will share the change in my github soon.
Please see https://github.com/chbae/meta-webosose/commit/28303f9b4ffe47f84630d6cff2f39ccccbd0fdcf and if you would like to install more opencv package, please add those in WEBOS_PACKAGESET_OPENCV variable of meta-webos/recipes-core/packagegroups/packagegroup-webos-extended.bb