Add rounding to InterpolateRow for improved quality and consistency.

source/scale_common.cc

 /*
  *  Copyright 2013 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 858 matching lines @@
   void (*InterpolateRow)(uint8* dst_argb, const uint8* src_argb,
       ptrdiff_t src_stride, int dst_width, int source_y_fraction) =
       InterpolateRow_C;
   const int max_y = (src_height > 1) ? ((src_height - 1) << 16) - 1 : 0;
   int j;
   assert(bpp >= 1 && bpp <= 4);
   assert(src_height != 0);
   assert(dst_width > 0);
   assert(dst_height > 0);
   src_argb += (x >> 16) * bpp;
-#if defined(HAS_INTERPOLATEROW_SSE2)
-  if (TestCpuFlag(kCpuHasSSE2)) {
-    InterpolateRow = InterpolateRow_Any_SSE2;
-    if (IS_ALIGNED(dst_width_bytes, 16)) {
-      InterpolateRow = InterpolateRow_SSE2;
-    }
-  }
-#endif
 #if defined(HAS_INTERPOLATEROW_SSSE3)
   if (TestCpuFlag(kCpuHasSSSE3)) {
     InterpolateRow = InterpolateRow_Any_SSSE3;
     if (IS_ALIGNED(dst_width_bytes, 16)) {
       InterpolateRow = InterpolateRow_SSSE3;
     }
   }
 #endif
 #if defined(HAS_INTERPOLATEROW_AVX2)
   if (TestCpuFlag(kCpuHasAVX2)) {
@@ skipping 231 matching lines @@
     *dx = -*dx;
     // src_width = -src_width;   // Caller must do this.
   }
 }
 #undef CENTERSTART
 
 #ifdef __cplusplus
 }  // extern "C"
 }  // namespace libyuv
 #endif