libavfilter/vf_sab.c: In function 'open_filter_param':
libavfilter/vf_sab.c:154:11: error: implicit declaration of function 'sws_get_gaussian_vec'; did you mean 'sws_getGaussianVec'? [-Werror=implicit-function-declaration]
     ret = sws_get_gaussian_vec(&vec, f->pre_filter_radius, f->quality);
           ^~~~~~~~~~~~~~~~~~~~
           sws_getGaussianVec
cc1: some warnings being treated as errors
make: *** [ffbuild/common.mak:81: libavfilter/vf_sab.o] Error 1
make: *** Waiting for unfinished jobs....