DIRECTION_45UP    222 libavfilter/vf_edgedetect.c         if (gy > -tan3pi8gx && gy < -tanpi8gx)  return DIRECTION_45UP;
DIRECTION_45UP    275 libavfilter/vf_edgedetect.c             case DIRECTION_45UP:        COPY_MAXIMA( 1, -1, -1,  1); break;