use rounding in scaledown by 2

source/scale.cc

 /*
  *  Copyright 2011 The LibYuv Project Authors. All rights reserved.
  *
  *  Use of this source code is governed by a BSD-style license
  *  that can be found in the LICENSE file in the root of the source
  *  tree. An additional intellectual property rights grant can be found
  *  in the file PATENTS. All contributing project authors may
  *  be found in the AUTHORS file in the root of the source tree.
  */
 
@@ skipping 43 matching lines @@
     ScaleRowDown2 = filtering == kFilterNone ? ScaleRowDown2_Any_NEON :
         (filtering == kFilterLinear ? ScaleRowDown2Linear_Any_NEON :
         ScaleRowDown2Box_Any_NEON);
     if (IS_ALIGNED(dst_width, 16)) {
       ScaleRowDown2 = filtering == kFilterNone ? ScaleRowDown2_NEON :
           (filtering == kFilterLinear ? ScaleRowDown2Linear_NEON :
           ScaleRowDown2Box_NEON);
     }
   }
 #endif
-#if defined(HAS_SCALEROWDOWN2_SSE2)
-  if (TestCpuFlag(kCpuHasSSE2)) {
-    ScaleRowDown2 = filtering == kFilterNone ? ScaleRowDown2_Any_SSE2 :
-        (filtering == kFilterLinear ? ScaleRowDown2Linear_Any_SSE2 :
-        ScaleRowDown2Box_Any_SSE2);
+#if defined(HAS_SCALEROWDOWN2_SSSE3)
+  if (TestCpuFlag(kCpuHasSSSE3)) {
+    ScaleRowDown2 = filtering == kFilterNone ? ScaleRowDown2_Any_SSSE3 :
+        (filtering == kFilterLinear ? ScaleRowDown2Linear_Any_SSSE3 :
+        ScaleRowDown2Box_Any_SSSE3);
     if (IS_ALIGNED(dst_width, 16)) {
-      ScaleRowDown2 = filtering == kFilterNone ? ScaleRowDown2_SSE2 :
-          (filtering == kFilterLinear ? ScaleRowDown2Linear_SSE2 :
-          ScaleRowDown2Box_SSE2);
+      ScaleRowDown2 = filtering == kFilterNone ? ScaleRowDown2_SSSE3 :
+          (filtering == kFilterLinear ? ScaleRowDown2Linear_SSSE3 :
+          ScaleRowDown2Box_SSSE3);
     }
   }
 #endif
 #if defined(HAS_SCALEROWDOWN2_AVX2)
   if (TestCpuFlag(kCpuHasAVX2)) {
     ScaleRowDown2 = filtering == kFilterNone ? ScaleRowDown2_Any_AVX2 :
         (filtering == kFilterLinear ? ScaleRowDown2Linear_Any_AVX2 :
         ScaleRowDown2Box_Any_AVX2);
     if (IS_ALIGNED(dst_width, 32)) {
       ScaleRowDown2 = filtering == kFilterNone ? ScaleRowDown2_AVX2 :
@@ skipping 1597 matching lines @@
                    dst_u, dst_halfwidth,
                    dst_v, dst_halfwidth,
                    dst_width, aheight,
                    interpolate ? kFilterBox : kFilterNone);
 }
 
 #ifdef __cplusplus
 }  // extern "C"
 }  // namespace libyuv
 #endif