| Index: base/gfx/convolver_unittest.cc
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| ===================================================================
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| --- base/gfx/convolver_unittest.cc	(revision 6142)
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| +++ base/gfx/convolver_unittest.cc	(working copy)
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| @@ -1,127 +0,0 @@
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| -// Copyright (c) 2006-2008 The Chromium Authors. All rights reserved.
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| -// Use of this source code is governed by a BSD-style license that can be
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| -// found in the LICENSE file.
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| -
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| -#include <string.h>
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| -#include <time.h>
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| -#include <vector>
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| -
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| -#include "base/gfx/convolver.h"
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| -#include "testing/gtest/include/gtest/gtest.h"
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| -
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| -namespace gfx {
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| -
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| -namespace {
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| -
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| -// Fills the given filter with impulse functions for the range 0->num_entries.
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| -  void FillImpulseFilter(int num_entries, ConvolusionFilter1D* filter) {
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| -  float one = 1.0f;
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| -  for (int i = 0; i < num_entries; i++)
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| -    filter->AddFilter(i, &one, 1);
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| -}
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| -
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| -// Filters the given input with the impulse function, and verifies that it
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| -// does not change.
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| -void TestImpulseConvolusion(const unsigned char* data, int width, int height) {
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| -  int byte_count = width * height * 4;
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| -
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| -  ConvolusionFilter1D filter_x;
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| -  FillImpulseFilter(width, &filter_x);
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| -
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| -  ConvolusionFilter1D filter_y;
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| -  FillImpulseFilter(height, &filter_y);
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| -
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| -  std::vector<unsigned char> output;
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| -  output.resize(byte_count);
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| -  BGRAConvolve2D(data, width * 4, true, filter_x, filter_y, &output[0]);
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| -
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| -  // Output should exactly match input.
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| -  EXPECT_EQ(0, memcmp(data, &output[0], byte_count));
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| -}
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| -
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| -// Fills the destination filter with a box filter averaging every two pixels
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| -// to produce the output.
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| -void FillBoxFilter(int size, ConvolusionFilter1D* filter) {
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| -  const float box[2] = { 0.5, 0.5 };
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| -  for (int i = 0; i < size; i++)
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| -    filter->AddFilter(i * 2, box, 2);
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| -}
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| -
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| -}  // namespace
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| -
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| -// Tests that each pixel, when set and run through the impulse filter, does
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| -// not change.
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| -TEST(Convolver, Impulse) {
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| -  // We pick an "odd" size that is not likely to fit on any boundaries so that
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| -  // we can see if all the widths and paddings are handled properly.
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| -  int width = 15;
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| -  int height = 31;
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| -  int byte_count = width * height * 4;
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| -  std::vector<unsigned char> input;
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| -  input.resize(byte_count);
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| -
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| -  unsigned char* input_ptr = &input[0];
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| -  for (int y = 0; y < height; y++) {
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| -    for (int x = 0; x < width; x++) {
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| -      for (int channel = 0; channel < 3; channel++) {
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| -        memset(input_ptr, 0, byte_count);
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| -        input_ptr[(y * width + x) * 4 + channel] = 0xff;
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| -        // Always set the alpha channel or it will attempt to "fix" it for us.
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| -        input_ptr[(y * width + x) * 4 + 3] = 0xff;
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| -        TestImpulseConvolusion(input_ptr, width, height);
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| -      }
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| -    }
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| -  }
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| -}
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| -
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| -// Tests that using a box filter to halve an image results in every square of 4
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| -// pixels in the original get averaged to a pixel in the output.
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| -TEST(Convolver, Halve) {
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| -  static const int kSize = 16;
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| -
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| -  int src_width = kSize;
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| -  int src_height = kSize;
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| -  int src_row_stride = src_width * 4;
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| -  int src_byte_count = src_row_stride * src_height;
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| -  std::vector<unsigned char> input;
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| -  input.resize(src_byte_count);
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| -
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| -  int dest_width = src_width / 2;
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| -  int dest_height = src_height / 2;
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| -  int dest_byte_count = dest_width * dest_height * 4;
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| -  std::vector<unsigned char> output;
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| -  output.resize(dest_byte_count);
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| -
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| -  // First fill the array with a bunch of random data.
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| -  srand(static_cast<unsigned>(time(NULL)));
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| -  for (int i = 0; i < src_byte_count; i++)
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| -    input[i] = rand() * 255 / RAND_MAX;
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| -
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| -  // Compute the filters.
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| -  ConvolusionFilter1D filter_x, filter_y;
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| -  FillBoxFilter(dest_width, &filter_x);
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| -  FillBoxFilter(dest_height, &filter_y);
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| -
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| -  // Do the convolusion.
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| -  BGRAConvolve2D(&input[0], src_width, true, filter_x, filter_y, &output[0]);
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| -
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| -  // Compute the expected results and check, allowing for a small difference
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| -  // to account for rounding errors.
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| -  for (int y = 0; y < dest_height; y++) {
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| -    for (int x = 0; x < dest_width; x++) {
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| -      for (int channel = 0; channel < 4; channel++) {
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| -        int src_offset = (y * 2 * src_row_stride + x * 2 * 4) + channel;
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| -        int value = input[src_offset] +  // Top left source pixel.
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| -                    input[src_offset + 4] +  // Top right source pixel.
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| -                    input[src_offset + src_row_stride] +  // Lower left.
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| -                    input[src_offset + src_row_stride + 4];  // Lower right.
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| -        value /= 4;  // Average.
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| -        int difference = value - output[(y * dest_width + x) * 4 + channel];
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| -        EXPECT_TRUE(difference >= -1 || difference <= 1);
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| -      }
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| -    }
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| -  }
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| -}
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| -
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| -}  // namespace gfx
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| -
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| 
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