The techniques of this disclosure apply to loop filtering across slice or tile boundaries in a video coding process. In one example, a method for performing loop filtering in a video coding process includes determining that pixels corresponding to filter coefficients of a filter mask for a loop filter are across a slice or tile boundary, removing filter coefficients corresponding to the pixels across the slice or tile boundary from the filter mask, renormalizing the filter mask without the removed filter coefficients, performing loop filtering using the renormalized filter mask.