diff --git a/test/dct16x16_test.cc b/test/dct16x16_test.cc
index 64f912a538ed5e09b7fcbad0978000068c63ffeb..57cc9176fc49c71d8999decd37bf7a66db8421f3 100644
--- a/test/dct16x16_test.cc
+++ b/test/dct16x16_test.cc
@@ -368,10 +368,10 @@ class Trans16x16TestBase {
 
       for (int j = 0; j < kNumCoeffs; ++j) {
 #if CONFIG_AOM_HIGHBITDEPTH
-        const uint32_t diff =
+        const int32_t diff =
             bit_depth_ == AOM_BITS_8 ? dst[j] - src[j] : dst16[j] - src16[j];
 #else
-        const uint32_t diff = dst[j] - src[j];
+        const int32_t diff = dst[j] - src[j];
 #endif
         const uint32_t error = diff * diff;
         if (max_error < error) max_error = error;
diff --git a/test/dct32x32_test.cc b/test/dct32x32_test.cc
index e2ca5c7724ca81a8cd870a68034e6d81c5d2a949..2cf047187a037567a06d38aaa55c1b596a1daaef 100644
--- a/test/dct32x32_test.cc
+++ b/test/dct32x32_test.cc
@@ -154,10 +154,10 @@ TEST_P(Trans32x32Test, AccuracyCheck) {
 
     for (int j = 0; j < kNumCoeffs; ++j) {
 #if CONFIG_AOM_HIGHBITDEPTH
-      const uint32_t diff =
+      const int32_t diff =
           bit_depth_ == AOM_BITS_8 ? dst[j] - src[j] : dst16[j] - src16[j];
 #else
-      const uint32_t diff = dst[j] - src[j];
+      const int32_t diff = dst[j] - src[j];
 #endif
       const uint32_t error = diff * diff;
       if (max_error < error) max_error = error;