diff --git a/libavfilter/vf_convolution.c b/libavfilter/vf_convolution.c
index 0b7356b320..3092c23402 100644
--- a/libavfilter/vf_convolution.c
+++ b/libavfilter/vf_convolution.c
@@ -628,10 +628,12 @@ static int filter_slice(AVFilterContext *ctx, void *arg, int jobnr, int nb_jobs)
             continue;
         }
         for (y = slice_start; y < slice_end; y += step) {
-            const int xoff = mode == MATRIX_COLUMN ? (y - slice_start) * bpc : radius * bpc;
-            const int yoff = mode == MATRIX_COLUMN ? radius * dstride : 0;
+            const int left = FFMIN(radius, sizew);
+            const int right = FFMAX(left, sizew - radius);
+            const int xoff = mode == MATRIX_COLUMN ? (y - slice_start) * bpc : left * bpc;
+            const int yoff = mode == MATRIX_COLUMN ? left * dstride : 0;
 
-            for (x = 0; x < radius; x++) {
+            for (x = 0; x < left; x++) {
                 const int xoff = mode == MATRIX_COLUMN ? (y - slice_start) * bpc : x * bpc;
                 const int yoff = mode == MATRIX_COLUMN ? x * dstride : 0;
 
@@ -640,11 +642,11 @@ static int filter_slice(AVFilterContext *ctx, void *arg, int jobnr, int nb_jobs)
                                  bias, matrix, c, s->max, radius,
                                  dstride, stride, slice_end - step);
             }
-            s->setup[plane](radius, c, src, stride, radius, width, y, height, bpc);
-            s->filter[plane](dst + yoff + xoff, sizew - 2 * radius,
+            s->setup[plane](radius, c, src, stride, left, width, y, height, bpc);
+            s->filter[plane](dst + yoff + xoff, right - left,
                              rdiv, bias, matrix, c, s->max, radius,
                              dstride, stride, slice_end - step);
-            for (x = sizew - radius; x < sizew; x++) {
+            for (x = right; x < sizew; x++) {
                 const int xoff = mode == MATRIX_COLUMN ? (y - slice_start) * bpc : x * bpc;
                 const int yoff = mode == MATRIX_COLUMN ? x * dstride : 0;