Add ARGBExtractAlpha function

unit_test/planar_test.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 2372 matching lines @@
   }
   for (int i = 0; i < kSize; ++i) {
     EXPECT_EQ(dst_pixels_c[i], dst_pixels_opt[i]);
   }
 
   free_aligned_buffer_64(dst_pixels_c);
   free_aligned_buffer_64(dst_pixels_opt);
   free_aligned_buffer_64(orig_pixels);
 }
 
+TEST_F(LibYUVPlanarTest, TestARGBExtractAlpha) {
+  const int kPixels = benchmark_width_ * benchmark_height_;
+  align_buffer_64(src_pixels, kPixels * 4);
+  align_buffer_64(dst_pixels_opt, kPixels);
+  align_buffer_64(dst_pixels_c, kPixels);
+
+  MemRandomize(src_pixels, kPixels * 4);
+  MemRandomize(dst_pixels_opt, kPixels);
+  memcpy(dst_pixels_c, dst_pixels_opt, kPixels);
+
+  MaskCpuFlags(disable_cpu_flags_);
+  ARGBExtractAlpha(src_pixels, benchmark_width_ * 4,
+                   dst_pixels_c, benchmark_width_,
+                   benchmark_width_, benchmark_height_);
+  MaskCpuFlags(benchmark_cpu_info_);
+
+  for (int i = 0; i < benchmark_iterations_; ++i) {
+    ARGBExtractAlpha(src_pixels, benchmark_width_ * 4,
+                     dst_pixels_opt, benchmark_width_,
+                     benchmark_width_, benchmark_height_);
+  }
+  for (int i = 0; i < kPixels; ++i) {
+    EXPECT_EQ(dst_pixels_c[i], dst_pixels_opt[i]);
+  }
+
+  free_aligned_buffer_64(dst_pixels_c);
+  free_aligned_buffer_64(dst_pixels_opt);
+  free_aligned_buffer_64(src_pixels);
+}
+
 TEST_F(LibYUVPlanarTest, TestARGBCopyYToAlpha) {
   const int kPixels = benchmark_width_ * benchmark_height_;
   align_buffer_64(orig_pixels, kPixels);
   align_buffer_64(dst_pixels_opt, kPixels * 4);
   align_buffer_64(dst_pixels_c, kPixels * 4);
 
   MemRandomize(orig_pixels, kPixels);
   MemRandomize(dst_pixels_opt, kPixels * 4);
   memcpy(dst_pixels_c, dst_pixels_opt, kPixels * 4);
 
@@ skipping 120 matching lines @@
 
 TEST_F(LibYUVPlanarTest, SetPlane_Opt) {
   int max_diff = TestARGBRect(benchmark_width_, benchmark_height_,
                               benchmark_iterations_,
                               disable_cpu_flags_, benchmark_cpu_info_,
                               +1, 0, 1);
   EXPECT_EQ(0, max_diff);
 }
 
 }  // namespace libyuv