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Diffstat (limited to 'skia/ext/convolver_unittest.cc')
-rw-r--r-- | skia/ext/convolver_unittest.cc | 128 |
1 files changed, 0 insertions, 128 deletions
diff --git a/skia/ext/convolver_unittest.cc b/skia/ext/convolver_unittest.cc deleted file mode 100644 index c0ae734..0000000 --- a/skia/ext/convolver_unittest.cc +++ /dev/null @@ -1,128 +0,0 @@ -// Copyright (c) 2006-2008 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. - -#include <string.h> -#include <time.h> -#include <vector> - -#include "skia/ext/convolver.h" - -#include "testing/gtest/include/gtest/gtest.h" - -namespace skia { - -namespace { - -// Fills the given filter with impulse functions for the range 0->num_entries. - void FillImpulseFilter(int num_entries, ConvolusionFilter1D* filter) { - float one = 1.0f; - for (int i = 0; i < num_entries; i++) - filter->AddFilter(i, &one, 1); -} - -// Filters the given input with the impulse function, and verifies that it -// does not change. -void TestImpulseConvolusion(const unsigned char* data, int width, int height) { - int byte_count = width * height * 4; - - ConvolusionFilter1D filter_x; - FillImpulseFilter(width, &filter_x); - - ConvolusionFilter1D filter_y; - FillImpulseFilter(height, &filter_y); - - std::vector<unsigned char> output; - output.resize(byte_count); - BGRAConvolve2D(data, width * 4, true, filter_x, filter_y, &output[0]); - - // Output should exactly match input. - EXPECT_EQ(0, memcmp(data, &output[0], byte_count)); -} - -// Fills the destination filter with a box filter averaging every two pixels -// to produce the output. -void FillBoxFilter(int size, ConvolusionFilter1D* filter) { - const float box[2] = { 0.5, 0.5 }; - for (int i = 0; i < size; i++) - filter->AddFilter(i * 2, box, 2); -} - -} // namespace - -// Tests that each pixel, when set and run through the impulse filter, does -// not change. -TEST(Convolver, Impulse) { - // We pick an "odd" size that is not likely to fit on any boundaries so that - // we can see if all the widths and paddings are handled properly. - int width = 15; - int height = 31; - int byte_count = width * height * 4; - std::vector<unsigned char> input; - input.resize(byte_count); - - unsigned char* input_ptr = &input[0]; - for (int y = 0; y < height; y++) { - for (int x = 0; x < width; x++) { - for (int channel = 0; channel < 3; channel++) { - memset(input_ptr, 0, byte_count); - input_ptr[(y * width + x) * 4 + channel] = 0xff; - // Always set the alpha channel or it will attempt to "fix" it for us. - input_ptr[(y * width + x) * 4 + 3] = 0xff; - TestImpulseConvolusion(input_ptr, width, height); - } - } - } -} - -// Tests that using a box filter to halve an image results in every square of 4 -// pixels in the original get averaged to a pixel in the output. -TEST(Convolver, Halve) { - static const int kSize = 16; - - int src_width = kSize; - int src_height = kSize; - int src_row_stride = src_width * 4; - int src_byte_count = src_row_stride * src_height; - std::vector<unsigned char> input; - input.resize(src_byte_count); - - int dest_width = src_width / 2; - int dest_height = src_height / 2; - int dest_byte_count = dest_width * dest_height * 4; - std::vector<unsigned char> output; - output.resize(dest_byte_count); - - // First fill the array with a bunch of random data. - srand(static_cast<unsigned>(time(NULL))); - for (int i = 0; i < src_byte_count; i++) - input[i] = rand() * 255 / RAND_MAX; - - // Compute the filters. - ConvolusionFilter1D filter_x, filter_y; - FillBoxFilter(dest_width, &filter_x); - FillBoxFilter(dest_height, &filter_y); - - // Do the convolusion. - BGRAConvolve2D(&input[0], src_width, true, filter_x, filter_y, &output[0]); - - // Compute the expected results and check, allowing for a small difference - // to account for rounding errors. - for (int y = 0; y < dest_height; y++) { - for (int x = 0; x < dest_width; x++) { - for (int channel = 0; channel < 4; channel++) { - int src_offset = (y * 2 * src_row_stride + x * 2 * 4) + channel; - int value = input[src_offset] + // Top left source pixel. - input[src_offset + 4] + // Top right source pixel. - input[src_offset + src_row_stride] + // Lower left. - input[src_offset + src_row_stride + 4]; // Lower right. - value /= 4; // Average. - int difference = value - output[(y * dest_width + x) * 4 + channel]; - EXPECT_TRUE(difference >= -1 || difference <= 1); - } - } - } -} - -} // namespace skia - |