将两个自定义过滤器组合成一个自定义过滤器的好方法是什么？

I've made two custom filters that are very similar. The only thing that's different between these two filters is the array that is being used. I thus want to make one custom filter and give it an array as a parameter. The arrays I'd then pass into the function would be $rootScope.selectedCategories and $rootScope.selectedBrands. Now my problem is that I don't know where to declare a variable that I can give as argument to the filter, as seen below.I've made two custom filters that are very simi