diff --git a/libavcodec/vc2enc.c b/libavcodec/vc2enc.c
index fa4ff54a3c..0a8c3633ef 100644
--- a/libavcodec/vc2enc.c
+++ b/libavcodec/vc2enc.c
@@ -1192,7 +1192,8 @@ static av_cold int vc2_encode_init(AVCodecContext *avctx)
         /* DWT init */
         if (ff_vc2enc_init_transforms(&s->transform_args[i].t,
                                       s->plane[i].coef_stride,
-                                      s->plane[i].dwt_height))
+                                      s->plane[i].dwt_height,
+                                      s->slice_width, s->slice_height))
             goto alloc_fail;
     }
 
diff --git a/libavcodec/vc2enc_dwt.c b/libavcodec/vc2enc_dwt.c
index c60b003a31..d22af8a313 100644
--- a/libavcodec/vc2enc_dwt.c
+++ b/libavcodec/vc2enc_dwt.c
@@ -255,21 +255,27 @@ static void vc2_subband_dwt_haar_shift(VC2TransformContext *t, dwtcoef *data,
     dwt_haar(t, data, stride, width, height, 1);
 }
 
-av_cold int ff_vc2enc_init_transforms(VC2TransformContext *s, int p_width, int p_height)
+av_cold int ff_vc2enc_init_transforms(VC2TransformContext *s, int p_stride,
+                                      int p_height, int slice_w, int slice_h)
 {
     s->vc2_subband_dwt[VC2_TRANSFORM_9_7]    = vc2_subband_dwt_97;
     s->vc2_subband_dwt[VC2_TRANSFORM_5_3]    = vc2_subband_dwt_53;
     s->vc2_subband_dwt[VC2_TRANSFORM_HAAR]   = vc2_subband_dwt_haar;
     s->vc2_subband_dwt[VC2_TRANSFORM_HAAR_S] = vc2_subband_dwt_haar_shift;
 
-    s->buffer = av_malloc(2*p_width*p_height*sizeof(dwtcoef));
+    /* Pad by the slice size, only matters for non-Haar wavelets */
+    s->buffer = av_calloc((p_stride + slice_w)*(p_height + slice_h), sizeof(dwtcoef));
     if (!s->buffer)
         return 1;
 
+    s->padding = (slice_h >> 1)*p_stride + (slice_w >> 1);
+    s->buffer += s->padding;
+
     return 0;
 }
 
 av_cold void ff_vc2enc_free_transforms(VC2TransformContext *s)
 {
-    av_freep(&s->buffer);
+    av_free(s->buffer - s->padding);
+    s->buffer = NULL;
 }
diff --git a/libavcodec/vc2enc_dwt.h b/libavcodec/vc2enc_dwt.h
index 7fbbfbe0ed..a6932bcdaf 100644
--- a/libavcodec/vc2enc_dwt.h
+++ b/libavcodec/vc2enc_dwt.h
@@ -41,12 +41,14 @@ enum VC2TransformType {
 
 typedef struct VC2TransformContext {
     dwtcoef *buffer;
+    int padding;
     void (*vc2_subband_dwt[VC2_TRANSFORMS_NB])(struct VC2TransformContext *t,
                                                dwtcoef *data, ptrdiff_t stride,
                                                int width, int height);
 } VC2TransformContext;
 
-int  ff_vc2enc_init_transforms(VC2TransformContext *t, int p_width, int p_height);
+int  ff_vc2enc_init_transforms(VC2TransformContext *t, int p_stride, int p_height,
+                               int slice_w, int slice_h);
 void ff_vc2enc_free_transforms(VC2TransformContext *t);
 
 #endif /* AVCODEC_VC2ENC_DWT_H */