Speed up vertical filtering using v = a+(b-a)*x formula...

media/tools/scaler_bench/scaler_bench.cc

 // Copyright (c) 2010 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 // This tool can be used to measure performace of video frame scaling
 // code. It times performance of the scaler with and without filtering.
 // It also measures performance of the Skia scaler for comparison.
 
 #include <iostream>
 #include <vector>
@@ skipping 182 matching lines @@
             << "x" << source_height << std::endl;
   std::cout << "Destination image size: " << dest_width
             << "x" << dest_height << std::endl;
   std::cout << "Number of frames: " << num_frames << std::endl;
   std::cout << "Number of buffers: " << num_buffers << std::endl;
 
   std::cout << "Skia: " << BenchmarkSkia()
             << "ms/frame" << std::endl;
   std::cout << "No filtering: " << BenchmarkFilter(media::FILTER_NONE)
             << "ms/frame" << std::endl;
+  std::cout << "Bilinear Vertical: "
+            << BenchmarkFilter(media::FILTER_BILINEAR_V)
+            << "ms/frame" << std::endl;
+  std::cout << "Bilinear Horizontal: "
+            << BenchmarkFilter(media::FILTER_BILINEAR_H)
+            << "ms/frame" << std::endl;
   std::cout << "Bilinear: " << BenchmarkFilter(media::FILTER_BILINEAR)
             << "ms/frame" << std::endl;
 
   return 0;
 }