diff --git a/examples/aom_cx_set_ref.c b/examples/aom_cx_set_ref.c
index d1aec99..ff24fa1 100644
--- a/examples/aom_cx_set_ref.c
+++ b/examples/aom_cx_set_ref.c
@@ -54,7 +54,7 @@
 #include "aom/aomcx.h"
 #include "aom/aom_decoder.h"
 #include "aom/aom_encoder.h"
-
+#include "examples/encoder_util.h"
 #include "./tools_common.h"
 #include "./video_writer.h"
 
@@ -68,128 +68,6 @@
   exit(EXIT_FAILURE);
 }
 
-static int compare_img(const aom_image_t *const img1,
-                       const aom_image_t *const img2) {
-  uint32_t l_w = img1->d_w;
-  uint32_t c_w = (img1->d_w + img1->x_chroma_shift) >> img1->x_chroma_shift;
-  const uint32_t c_h =
-      (img1->d_h + img1->y_chroma_shift) >> img1->y_chroma_shift;
-  uint32_t i;
-  int match = 1;
-
-  match &= (img1->fmt == img2->fmt);
-  match &= (img1->d_w == img2->d_w);
-  match &= (img1->d_h == img2->d_h);
-
-  for (i = 0; i < img1->d_h; ++i)
-    match &= (memcmp(img1->planes[AOM_PLANE_Y] + i * img1->stride[AOM_PLANE_Y],
-                     img2->planes[AOM_PLANE_Y] + i * img2->stride[AOM_PLANE_Y],
-                     l_w) == 0);
-
-  for (i = 0; i < c_h; ++i)
-    match &= (memcmp(img1->planes[AOM_PLANE_U] + i * img1->stride[AOM_PLANE_U],
-                     img2->planes[AOM_PLANE_U] + i * img2->stride[AOM_PLANE_U],
-                     c_w) == 0);
-
-  for (i = 0; i < c_h; ++i)
-    match &= (memcmp(img1->planes[AOM_PLANE_V] + i * img1->stride[AOM_PLANE_V],
-                     img2->planes[AOM_PLANE_V] + i * img2->stride[AOM_PLANE_V],
-                     c_w) == 0);
-
-  return match;
-}
-
-#define mmin(a, b) ((a) < (b) ? (a) : (b))
-static void find_mismatch(const aom_image_t *const img1,
-                          const aom_image_t *const img2, int yloc[4],
-                          int uloc[4], int vloc[4]) {
-  const uint32_t bsize = 64;
-  const uint32_t bsizey = bsize >> img1->y_chroma_shift;
-  const uint32_t bsizex = bsize >> img1->x_chroma_shift;
-  const uint32_t c_w =
-      (img1->d_w + img1->x_chroma_shift) >> img1->x_chroma_shift;
-  const uint32_t c_h =
-      (img1->d_h + img1->y_chroma_shift) >> img1->y_chroma_shift;
-  int match = 1;
-  uint32_t i, j;
-  yloc[0] = yloc[1] = yloc[2] = yloc[3] = -1;
-  for (i = 0, match = 1; match && i < img1->d_h; i += bsize) {
-    for (j = 0; match && j < img1->d_w; j += bsize) {
-      int k, l;
-      const int si = mmin(i + bsize, img1->d_h) - i;
-      const int sj = mmin(j + bsize, img1->d_w) - j;
-      for (k = 0; match && k < si; ++k) {
-        for (l = 0; match && l < sj; ++l) {
-          if (*(img1->planes[AOM_PLANE_Y] +
-                (i + k) * img1->stride[AOM_PLANE_Y] + j + l) !=
-              *(img2->planes[AOM_PLANE_Y] +
-                (i + k) * img2->stride[AOM_PLANE_Y] + j + l)) {
-            yloc[0] = i + k;
-            yloc[1] = j + l;
-            yloc[2] = *(img1->planes[AOM_PLANE_Y] +
-                        (i + k) * img1->stride[AOM_PLANE_Y] + j + l);
-            yloc[3] = *(img2->planes[AOM_PLANE_Y] +
-                        (i + k) * img2->stride[AOM_PLANE_Y] + j + l);
-            match = 0;
-            break;
-          }
-        }
-      }
-    }
-  }
-
-  uloc[0] = uloc[1] = uloc[2] = uloc[3] = -1;
-  for (i = 0, match = 1; match && i < c_h; i += bsizey) {
-    for (j = 0; match && j < c_w; j += bsizex) {
-      int k, l;
-      const int si = mmin(i + bsizey, c_h - i);
-      const int sj = mmin(j + bsizex, c_w - j);
-      for (k = 0; match && k < si; ++k) {
-        for (l = 0; match && l < sj; ++l) {
-          if (*(img1->planes[AOM_PLANE_U] +
-                (i + k) * img1->stride[AOM_PLANE_U] + j + l) !=
-              *(img2->planes[AOM_PLANE_U] +
-                (i + k) * img2->stride[AOM_PLANE_U] + j + l)) {
-            uloc[0] = i + k;
-            uloc[1] = j + l;
-            uloc[2] = *(img1->planes[AOM_PLANE_U] +
-                        (i + k) * img1->stride[AOM_PLANE_U] + j + l);
-            uloc[3] = *(img2->planes[AOM_PLANE_U] +
-                        (i + k) * img2->stride[AOM_PLANE_U] + j + l);
-            match = 0;
-            break;
-          }
-        }
-      }
-    }
-  }
-  vloc[0] = vloc[1] = vloc[2] = vloc[3] = -1;
-  for (i = 0, match = 1; match && i < c_h; i += bsizey) {
-    for (j = 0; match && j < c_w; j += bsizex) {
-      int k, l;
-      const int si = mmin(i + bsizey, c_h - i);
-      const int sj = mmin(j + bsizex, c_w - j);
-      for (k = 0; match && k < si; ++k) {
-        for (l = 0; match && l < sj; ++l) {
-          if (*(img1->planes[AOM_PLANE_V] +
-                (i + k) * img1->stride[AOM_PLANE_V] + j + l) !=
-              *(img2->planes[AOM_PLANE_V] +
-                (i + k) * img2->stride[AOM_PLANE_V] + j + l)) {
-            vloc[0] = i + k;
-            vloc[1] = j + l;
-            vloc[2] = *(img1->planes[AOM_PLANE_V] +
-                        (i + k) * img1->stride[AOM_PLANE_V] + j + l);
-            vloc[3] = *(img2->planes[AOM_PLANE_V] +
-                        (i + k) * img2->stride[AOM_PLANE_V] + j + l);
-            match = 0;
-            break;
-          }
-        }
-      }
-    }
-  }
-}
-
 static void testing_decode(aom_codec_ctx_t *encoder, aom_codec_ctx_t *decoder,
                            unsigned int frame_out, int *mismatch_seen) {
   aom_image_t enc_img, dec_img;
@@ -206,12 +84,12 @@
     die_codec(decoder, "Failed to get decoder reference frame");
   dec_img = ref_dec.img;
 
-  if (!compare_img(&enc_img, &dec_img)) {
+  if (!aom_compare_img(&enc_img, &dec_img)) {
     int y[4], u[4], v[4];
 
     *mismatch_seen = 1;
 
-    find_mismatch(&enc_img, &dec_img, y, u, v);
+    aom_find_mismatch(&enc_img, &dec_img, y, u, v);
     printf(
         "Encode/decode mismatch on frame %d at"
         " Y[%d, %d] {%d/%d},"