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// Copyright (c) 2012 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 "ui/gfx/skbitmap_operations.h"
#include <stdint.h>
#include "testing/gtest/include/gtest/gtest.h"
#include "third_party/skia/include/core/SkBitmap.h"
#include "third_party/skia/include/core/SkCanvas.h"
#include "third_party/skia/include/core/SkColorPriv.h"
#include "third_party/skia/include/core/SkRect.h"
#include "third_party/skia/include/core/SkRegion.h"
#include "third_party/skia/include/core/SkUnPreMultiply.h"
namespace {
// Returns true if each channel of the given two colors are "close." This is
// used for comparing colors where rounding errors may cause off-by-one.
inline bool ColorsClose(uint32_t a, uint32_t b) {
return abs(static_cast<int>(SkColorGetB(a) - SkColorGetB(b))) <= 2 &&
abs(static_cast<int>(SkColorGetG(a) - SkColorGetG(b))) <= 2 &&
abs(static_cast<int>(SkColorGetR(a) - SkColorGetR(b))) <= 2 &&
abs(static_cast<int>(SkColorGetA(a) - SkColorGetA(b))) <= 2;
}
inline bool MultipliedColorsClose(uint32_t a, uint32_t b) {
return ColorsClose(SkUnPreMultiply::PMColorToColor(a),
SkUnPreMultiply::PMColorToColor(b));
}
bool BitmapsClose(const SkBitmap& a, const SkBitmap& b) {
for (int y = 0; y < a.height(); y++) {
for (int x = 0; x < a.width(); x++) {
SkColor a_pixel = *a.getAddr32(x, y);
SkColor b_pixel = *b.getAddr32(x, y);
if (!ColorsClose(a_pixel, b_pixel))
return false;
}
}
return true;
}
void FillDataToBitmap(int w, int h, SkBitmap* bmp) {
bmp->allocN32Pixels(w, h);
unsigned char* src_data =
reinterpret_cast<unsigned char*>(bmp->getAddr32(0, 0));
for (int i = 0; i < w * h; i++) {
const int alpha = i % 256;
src_data[i * 4 + 0] = static_cast<unsigned char>(alpha);
src_data[i * 4 + 1] = static_cast<unsigned char>((i + 16) % (alpha + 1));
src_data[i * 4 + 2] = static_cast<unsigned char>((i + 32) % (alpha + 1));
src_data[i * 4 + 3] = static_cast<unsigned char>((i + 64) % (alpha + 1));
}
}
// The reference (i.e., old) implementation of |CreateHSLShiftedBitmap()|.
SkBitmap ReferenceCreateHSLShiftedBitmap(
const SkBitmap& bitmap,
color_utils::HSL hsl_shift) {
SkBitmap shifted;
shifted.allocN32Pixels(bitmap.width(), bitmap.height());
shifted.eraseARGB(0, 0, 0, 0);
// Loop through the pixels of the original bitmap.
for (int y = 0; y < bitmap.height(); ++y) {
SkPMColor* pixels = bitmap.getAddr32(0, y);
SkPMColor* tinted_pixels = shifted.getAddr32(0, y);
for (int x = 0; x < bitmap.width(); ++x) {
tinted_pixels[x] = SkPreMultiplyColor(color_utils::HSLShift(
SkUnPreMultiply::PMColorToColor(pixels[x]), hsl_shift));
}
}
return shifted;
}
} // namespace
// Invert bitmap and verify the each pixel is inverted and the alpha value is
// not changed.
TEST(SkBitmapOperationsTest, CreateInvertedBitmap) {
int src_w = 16, src_h = 16;
SkBitmap src;
src.allocN32Pixels(src_w, src_h);
for (int y = 0; y < src_h; y++) {
for (int x = 0; x < src_w; x++) {
int i = y * src_w + x;
*src.getAddr32(x, y) =
SkColorSetARGB((255 - i) % 255, i % 255, i * 4 % 255, 0);
}
}
SkBitmap inverted = SkBitmapOperations::CreateInvertedBitmap(src);
for (int y = 0; y < src_h; y++) {
for (int x = 0; x < src_w; x++) {
int i = y * src_w + x;
EXPECT_EQ(static_cast<unsigned int>((255 - i) % 255),
SkColorGetA(*inverted.getAddr32(x, y)));
EXPECT_EQ(static_cast<unsigned int>(255 - (i % 255)),
SkColorGetR(*inverted.getAddr32(x, y)));
EXPECT_EQ(static_cast<unsigned int>(255 - (i * 4 % 255)),
SkColorGetG(*inverted.getAddr32(x, y)));
EXPECT_EQ(static_cast<unsigned int>(255),
SkColorGetB(*inverted.getAddr32(x, y)));
}
}
}
// Blend two bitmaps together at 50% alpha and verify that the result
// is the middle-blend of the two.
TEST(SkBitmapOperationsTest, CreateBlendedBitmap) {
int src_w = 16, src_h = 16;
SkBitmap src_a;
src_a.allocN32Pixels(src_w, src_h);
SkBitmap src_b;
src_b.allocN32Pixels(src_w, src_h);
for (int y = 0, i = 0; y < src_h; y++) {
for (int x = 0; x < src_w; x++) {
*src_a.getAddr32(x, y) = SkColorSetARGB(255, 0, i * 2 % 255, i % 255);
*src_b.getAddr32(x, y) =
SkColorSetARGB((255 - i) % 255, i % 255, i * 4 % 255, 0);
i++;
}
}
// Shift to red.
SkBitmap blended = SkBitmapOperations::CreateBlendedBitmap(
src_a, src_b, 0.5);
for (int y = 0; y < src_h; y++) {
for (int x = 0; x < src_w; x++) {
int i = y * src_w + x;
EXPECT_EQ(static_cast<unsigned int>((255 + ((255 - i) % 255)) / 2),
SkColorGetA(*blended.getAddr32(x, y)));
EXPECT_EQ(static_cast<unsigned int>(i % 255 / 2),
SkColorGetR(*blended.getAddr32(x, y)));
EXPECT_EQ((static_cast<unsigned int>((i * 2) % 255 + (i * 4) % 255) / 2),
SkColorGetG(*blended.getAddr32(x, y)));
EXPECT_EQ(static_cast<unsigned int>(i % 255 / 2),
SkColorGetB(*blended.getAddr32(x, y)));
}
}
}
// Test our masking functions.
TEST(SkBitmapOperationsTest, CreateMaskedBitmap) {
const int src_w = 16, src_h = 16;
SkBitmap src;
FillDataToBitmap(src_w, src_h, &src);
SkBitmap alpha;
alpha.allocN32Pixels(src_w, src_h);
for (int y = 0, i = 0; y < src_h; y++) {
for (int x = 0; x < src_w; x++) {
*alpha.getAddr32(x, y) = SkPackARGB32(i % 256, 0, 0, 0);
i++;
}
}
SkBitmap masked = SkBitmapOperations::CreateMaskedBitmap(src, alpha);
for (int y = 0; y < src_h; y++) {
for (int x = 0; x < src_w; x++) {
int alpha_pixel = *alpha.getAddr32(x, y);
int src_pixel = *src.getAddr32(x, y);
int masked_pixel = *masked.getAddr32(x, y);
int scale = SkAlpha255To256(SkGetPackedA32(alpha_pixel));
int src_a = (src_pixel >> SK_A32_SHIFT) & 0xFF;
int src_r = (src_pixel >> SK_R32_SHIFT) & 0xFF;
int src_g = (src_pixel >> SK_G32_SHIFT) & 0xFF;
int src_b = (src_pixel >> SK_B32_SHIFT) & 0xFF;
int masked_a = (masked_pixel >> SK_A32_SHIFT) & 0xFF;
int masked_r = (masked_pixel >> SK_R32_SHIFT) & 0xFF;
int masked_g = (masked_pixel >> SK_G32_SHIFT) & 0xFF;
int masked_b = (masked_pixel >> SK_B32_SHIFT) & 0xFF;
EXPECT_EQ((src_a * scale) >> 8, masked_a);
EXPECT_EQ((src_r * scale) >> 8, masked_r);
EXPECT_EQ((src_g * scale) >> 8, masked_g);
EXPECT_EQ((src_b * scale) >> 8, masked_b);
}
}
}
// Make sure that when shifting a bitmap without any shift parameters,
// the end result is close enough to the original (rounding errors
// notwithstanding).
TEST(SkBitmapOperationsTest, CreateHSLShiftedBitmapToSame) {
int src_w = 16, src_h = 16;
SkBitmap src;
src.allocN32Pixels(src_w, src_h);
for (int y = 0, i = 0; y < src_h; y++) {
for (int x = 0; x < src_w; x++) {
*src.getAddr32(x, y) = SkPreMultiplyColor(SkColorSetARGB((i + 128) % 255,
(i + 128) % 255, (i + 64) % 255, (i + 0) % 255));
i++;
}
}
color_utils::HSL hsl = { -1, -1, -1 };
SkBitmap shifted = ReferenceCreateHSLShiftedBitmap(src, hsl);
for (int y = 0; y < src_h; y++) {
for (int x = 0; x < src_w; x++) {
SkColor src_pixel = *src.getAddr32(x, y);
SkColor shifted_pixel = *shifted.getAddr32(x, y);
EXPECT_TRUE(MultipliedColorsClose(src_pixel, shifted_pixel)) <<
"source: (a,r,g,b) = (" << SkColorGetA(src_pixel) << "," <<
SkColorGetR(src_pixel) << "," <<
SkColorGetG(src_pixel) << "," <<
SkColorGetB(src_pixel) << "); " <<
"shifted: (a,r,g,b) = (" << SkColorGetA(shifted_pixel) << "," <<
SkColorGetR(shifted_pixel) << "," <<
SkColorGetG(shifted_pixel) << "," <<
SkColorGetB(shifted_pixel) << ")";
}
}
}
// Shift a blue bitmap to red.
TEST(SkBitmapOperationsTest, CreateHSLShiftedBitmapHueOnly) {
int src_w = 16, src_h = 16;
SkBitmap src;
src.allocN32Pixels(src_w, src_h);
for (int y = 0, i = 0; y < src_h; y++) {
for (int x = 0; x < src_w; x++) {
*src.getAddr32(x, y) = SkColorSetARGB(255, 0, 0, i % 255);
i++;
}
}
// Shift to red.
color_utils::HSL hsl = { 0, -1, -1 };
SkBitmap shifted = SkBitmapOperations::CreateHSLShiftedBitmap(src, hsl);
for (int y = 0, i = 0; y < src_h; y++) {
for (int x = 0; x < src_w; x++) {
EXPECT_TRUE(ColorsClose(shifted.getColor(x, y),
SkColorSetARGB(255, i % 255, 0, 0)));
i++;
}
}
}
// Validate HSL shift.
TEST(SkBitmapOperationsTest, ValidateHSLShift) {
// Note: 255/51 = 5 (exactly) => 6 including 0!
const int inc = 51;
const int dim = 255 / inc + 1;
SkBitmap src;
src.allocN32Pixels(dim*dim, dim*dim);
for (int a = 0, y = 0; a <= 255; a += inc) {
for (int r = 0; r <= 255; r += inc, y++) {
for (int g = 0, x = 0; g <= 255; g += inc) {
for (int b = 0; b <= 255; b+= inc, x++) {
*src.getAddr32(x, y) =
SkPreMultiplyColor(SkColorSetARGB(a, r, g, b));
}
}
}
}
// Shhhh. The spec says I should set things to -1 for "no change", but
// actually -0.1 will do. Don't tell anyone I did this.
for (double h = -0.1; h <= 1.0001; h += 0.1) {
for (double s = -0.1; s <= 1.0001; s += 0.1) {
for (double l = -0.1; l <= 1.0001; l += 0.1) {
color_utils::HSL hsl = { h, s, l };
SkBitmap ref_shifted = ReferenceCreateHSLShiftedBitmap(src, hsl);
SkBitmap shifted = SkBitmapOperations::CreateHSLShiftedBitmap(src, hsl);
EXPECT_TRUE(BitmapsClose(ref_shifted, shifted))
<< "h = " << h << ", s = " << s << ", l = " << l;
}
}
}
}
// Test our cropping.
TEST(SkBitmapOperationsTest, CreateCroppedBitmap) {
int src_w = 16, src_h = 16;
SkBitmap src;
FillDataToBitmap(src_w, src_h, &src);
SkBitmap cropped = SkBitmapOperations::CreateTiledBitmap(src, 4, 4,
8, 8);
ASSERT_EQ(8, cropped.width());
ASSERT_EQ(8, cropped.height());
for (int y = 4; y < 12; y++) {
for (int x = 4; x < 12; x++) {
EXPECT_EQ(*src.getAddr32(x, y),
*cropped.getAddr32(x - 4, y - 4));
}
}
}
// Test whether our cropping correctly wraps across image boundaries.
TEST(SkBitmapOperationsTest, CreateCroppedBitmapWrapping) {
int src_w = 16, src_h = 16;
SkBitmap src;
FillDataToBitmap(src_w, src_h, &src);
SkBitmap cropped = SkBitmapOperations::CreateTiledBitmap(
src, src_w / 2, src_h / 2, src_w, src_h);
ASSERT_EQ(src_w, cropped.width());
ASSERT_EQ(src_h, cropped.height());
for (int y = 0; y < src_h; y++) {
for (int x = 0; x < src_w; x++) {
EXPECT_EQ(*src.getAddr32(x, y),
*cropped.getAddr32((x + src_w / 2) % src_w,
(y + src_h / 2) % src_h));
}
}
}
TEST(SkBitmapOperationsTest, DownsampleByTwo) {
// Use an odd-sized bitmap to make sure the edge cases where there isn't a
// 2x2 block of pixels is handled correctly.
// Here's the ARGB example
//
// 50% transparent green opaque 50% blue white
// 80008000 FF000080 FFFFFFFF
//
// 50% transparent red opaque 50% gray black
// 80800000 80808080 FF000000
//
// black white 50% gray
// FF000000 FFFFFFFF FF808080
//
// The result of this computation should be:
// A0404040 FF808080
// FF808080 FF808080
SkBitmap input;
input.allocN32Pixels(3, 3);
// The color order may be different, but we don't care (the channels are
// trated the same).
*input.getAddr32(0, 0) = 0x80008000;
*input.getAddr32(1, 0) = 0xFF000080;
*input.getAddr32(2, 0) = 0xFFFFFFFF;
*input.getAddr32(0, 1) = 0x80800000;
*input.getAddr32(1, 1) = 0x80808080;
*input.getAddr32(2, 1) = 0xFF000000;
*input.getAddr32(0, 2) = 0xFF000000;
*input.getAddr32(1, 2) = 0xFFFFFFFF;
*input.getAddr32(2, 2) = 0xFF808080;
SkBitmap result = SkBitmapOperations::DownsampleByTwo(input);
EXPECT_EQ(2, result.width());
EXPECT_EQ(2, result.height());
// Some of the values are off-by-one due to rounding.
EXPECT_EQ(0x9f404040, *result.getAddr32(0, 0));
EXPECT_EQ(0xFF7f7f7f, *result.getAddr32(1, 0));
EXPECT_EQ(0xFF7f7f7f, *result.getAddr32(0, 1));
EXPECT_EQ(0xFF808080, *result.getAddr32(1, 1));
}
// Test edge cases for DownsampleByTwo.
TEST(SkBitmapOperationsTest, DownsampleByTwoSmall) {
SkPMColor reference = 0xFF4080FF;
// Test a 1x1 bitmap.
SkBitmap one_by_one;
one_by_one.allocN32Pixels(1, 1);
*one_by_one.getAddr32(0, 0) = reference;
SkBitmap result = SkBitmapOperations::DownsampleByTwo(one_by_one);
EXPECT_EQ(1, result.width());
EXPECT_EQ(1, result.height());
EXPECT_EQ(reference, *result.getAddr32(0, 0));
// Test an n by 1 bitmap.
SkBitmap one_by_n;
one_by_n.allocN32Pixels(300, 1);
result = SkBitmapOperations::DownsampleByTwo(one_by_n);
EXPECT_EQ(300, result.width());
EXPECT_EQ(1, result.height());
// Test a 1 by n bitmap.
SkBitmap n_by_one;
n_by_one.allocN32Pixels(1, 300);
result = SkBitmapOperations::DownsampleByTwo(n_by_one);
EXPECT_EQ(1, result.width());
EXPECT_EQ(300, result.height());
// Test an empty bitmap
SkBitmap empty;
result = SkBitmapOperations::DownsampleByTwo(empty);
EXPECT_TRUE(result.isNull());
EXPECT_EQ(0, result.width());
EXPECT_EQ(0, result.height());
}
// Here we assume DownsampleByTwo works correctly (it's tested above) and
// just make sure that the wrapper function does the right thing.
TEST(SkBitmapOperationsTest, DownsampleByTwoUntilSize) {
// First make sure a "too small" bitmap doesn't get modified at all.
SkBitmap too_small;
too_small.allocN32Pixels(10, 10);
SkBitmap result = SkBitmapOperations::DownsampleByTwoUntilSize(
too_small, 16, 16);
EXPECT_EQ(10, result.width());
EXPECT_EQ(10, result.height());
// Now make sure giving it a 0x0 target returns something reasonable.
result = SkBitmapOperations::DownsampleByTwoUntilSize(too_small, 0, 0);
EXPECT_EQ(1, result.width());
EXPECT_EQ(1, result.height());
// Test multiple steps of downsampling.
SkBitmap large;
large.allocN32Pixels(100, 43);
result = SkBitmapOperations::DownsampleByTwoUntilSize(large, 6, 6);
// The result should be divided in half 100x43 -> 50x22 -> 25x11
EXPECT_EQ(25, result.width());
EXPECT_EQ(11, result.height());
}
TEST(SkBitmapOperationsTest, UnPreMultiply) {
SkBitmap input;
input.allocN32Pixels(2, 2);
EXPECT_EQ(input.alphaType(), kPremul_SkAlphaType);
// Set PMColors into the bitmap
*input.getAddr32(0, 0) = SkPackARGB32NoCheck(0x80, 0x00, 0x00, 0x00);
*input.getAddr32(1, 0) = SkPackARGB32NoCheck(0x80, 0x80, 0x80, 0x80);
*input.getAddr32(0, 1) = SkPackARGB32NoCheck(0xFF, 0x00, 0xCC, 0x88);
*input.getAddr32(1, 1) = SkPackARGB32NoCheck(0x00, 0x00, 0xCC, 0x88);
SkBitmap result = SkBitmapOperations::UnPreMultiply(input);
EXPECT_EQ(result.alphaType(), kUnpremul_SkAlphaType);
EXPECT_EQ(2, result.width());
EXPECT_EQ(2, result.height());
EXPECT_NE(result.getPixels(), input.getPixels());
EXPECT_EQ(0x80000000, *result.getAddr32(0, 0));
EXPECT_EQ(0x80FFFFFF, *result.getAddr32(1, 0));
EXPECT_EQ(0xFF00CC88, *result.getAddr32(0, 1));
EXPECT_EQ(0x00000000u, *result.getAddr32(1, 1)); // "Division by zero".
}
TEST(SkBitmapOperationsTest, UnPreMultiplyOpaque) {
SkBitmap input;
input.allocN32Pixels(2, 2, true);
EXPECT_EQ(input.alphaType(), kOpaque_SkAlphaType);
SkBitmap result = SkBitmapOperations::UnPreMultiply(input);
EXPECT_EQ(result.alphaType(), kOpaque_SkAlphaType);
EXPECT_EQ(result.getPixels(), input.getPixels());
}
TEST(SkBitmapOperationsTest, UnPreMultiplyAlreadyUnPreMultiplied) {
SkBitmap input;
input.allocN32Pixels(2, 2);
input.setAlphaType(kUnpremul_SkAlphaType);
EXPECT_EQ(input.alphaType(), kUnpremul_SkAlphaType);
SkBitmap result = SkBitmapOperations::UnPreMultiply(input);
EXPECT_EQ(result.alphaType(), kUnpremul_SkAlphaType);
EXPECT_EQ(result.getPixels(), input.getPixels());
}
TEST(SkBitmapOperationsTest, CreateTransposedBitmap) {
SkBitmap input;
input.allocN32Pixels(2, 3);
for (int x = 0; x < input.width(); ++x) {
for (int y = 0; y < input.height(); ++y) {
*input.getAddr32(x, y) = x * input.width() + y;
}
}
SkBitmap result = SkBitmapOperations::CreateTransposedBitmap(input);
EXPECT_EQ(3, result.width());
EXPECT_EQ(2, result.height());
for (int x = 0; x < input.width(); ++x) {
for (int y = 0; y < input.height(); ++y) {
EXPECT_EQ(*input.getAddr32(x, y), *result.getAddr32(y, x));
}
}
}
void DrawRectWithColor(SkCanvas* canvas,
int left,
int top,
int right,
int bottom,
SkColor color) {
SkPaint paint;
paint.setColor(color);
paint.setBlendMode(SkBlendMode::kSrc);
canvas->drawRect(
SkRect::MakeLTRB(SkIntToScalar(left), SkIntToScalar(top),
SkIntToScalar(right), SkIntToScalar(bottom)),
paint);
}
// Check that Rotate provides the desired results
TEST(SkBitmapOperationsTest, RotateImage) {
const int src_w = 6, src_h = 4;
SkBitmap src;
// Create a simple 4 color bitmap:
// RRRBBB
// RRRBBB
// GGGYYY
// GGGYYY
src.allocN32Pixels(src_w, src_h);
SkCanvas canvas(src, SkSurfaceProps{});
src.eraseARGB(0, 0, 0, 0);
// This region is a semi-transparent red to test non-opaque pixels.
DrawRectWithColor(&canvas, 0, 0, src_w / 2, src_h / 2, 0x1FFF0000);
DrawRectWithColor(&canvas, src_w / 2, 0, src_w, src_h / 2, SK_ColorBLUE);
DrawRectWithColor(&canvas, 0, src_h / 2, src_w / 2, src_h, SK_ColorGREEN);
DrawRectWithColor(&canvas, src_w / 2, src_h / 2, src_w, src_h,
SK_ColorYELLOW);
SkBitmap rotate90, rotate180, rotate270;
rotate90 = SkBitmapOperations::Rotate(src,
SkBitmapOperations::ROTATION_90_CW);
rotate180 = SkBitmapOperations::Rotate(src,
SkBitmapOperations::ROTATION_180_CW);
rotate270 = SkBitmapOperations::Rotate(src,
SkBitmapOperations::ROTATION_270_CW);
ASSERT_EQ(rotate90.width(), src.height());
ASSERT_EQ(rotate90.height(), src.width());
ASSERT_EQ(rotate180.width(), src.width());
ASSERT_EQ(rotate180.height(), src.height());
ASSERT_EQ(rotate270.width(), src.height());
ASSERT_EQ(rotate270.height(), src.width());
for (int x=0; x < src_w; ++x) {
for (int y=0; y < src_h; ++y) {
ASSERT_EQ(*src.getAddr32(x,y), *rotate90.getAddr32(src_h - (y+1),x));
ASSERT_EQ(*src.getAddr32(x,y), *rotate270.getAddr32(y, src_w - (x+1)));
ASSERT_EQ(*src.getAddr32(x,y),
*rotate180.getAddr32(src_w - (x+1), src_h - (y+1)));
}
}
}