image_decoder_no_gl_unittests.cc

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// Copyright 2013 The Flutter 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 "flutter/lib/ui/painting/image_decoder_no_gl_unittests.h"
#include <memory>
 
#include "flutter/fml/endianness.h"
#include "impeller/renderer/capabilities.h"
#include "include/core/SkColorType.h"
#include "third_party/skia/include/codec/SkPngDecoder.h"
 
namespace flutter {
namespace testing {
 
// Tests are disabled for fuchsia.
#if defined(OS_FUCHSIA)
#pragma GCC diagnostic ignored "-Wunreachable-code"
#endif
 
namespace {
 
bool IsPngWithPLTE(const uint8_t* bytes, size_t size) {
  constexpr std::string_view kPngMagic = "\x89PNG\x0d\x0a\x1a\x0a";
  constexpr std::string_view kPngPlte = "PLTE";
  constexpr uint32_t kLengthBytes = 4;
  constexpr uint32_t kTypeBytes = 4;
  constexpr uint32_t kCrcBytes = 4;
 
  if (size < kPngMagic.size()) {
    return false;
  }
 
  if (memcmp(bytes, kPngMagic.data(), kPngMagic.size()) != 0) {
    return false;
  }
 
  const uint8_t* end = bytes + size;
  const uint8_t* loc = bytes + kPngMagic.size();
  while (loc + kLengthBytes + kTypeBytes <= end) {
    uint32_t chunk_length =
        fml::BigEndianToArch(*reinterpret_cast<const uint32_t*>(loc));
 
    if (memcmp(loc + kLengthBytes, kPngPlte.data(), kPngPlte.size()) == 0) {
      return true;
    }
 
    loc += kLengthBytes + kTypeBytes + chunk_length + kCrcBytes;
  }
 
  return false;
}
 
}  // namespace
 
float HalfToFloat(uint16_t half) {
  switch (half) {
    case 0x7c00:
      return std::numeric_limits<float>::infinity();
    case 0xfc00:
      return -std::numeric_limits<float>::infinity();
  }
  bool negative = half >> 15;
  uint16_t exponent = (half >> 10) & 0x1f;
  uint16_t fraction = half & 0x3ff;
  float fExponent = exponent - 15.0f;
  float fFraction = static_cast<float>(fraction) / 1024.f;
  float pow_value = powf(2.0f, fExponent);
  return (negative ? -1.f : 1.f) * pow_value * (1.0f + fFraction);
}
 
float DecodeBGR10(uint32_t x) {
  const float max = 1.25098f;
  const float min = -0.752941f;
  const float intercept = min;
  const float slope = (max - min) / 1024.0f;
  return (x * slope) + intercept;
}
 
TEST(ImageDecoderNoGLTest, ImpellerWideGamutDisplayP3) {
#if defined(OS_FUCHSIA)
  GTEST_SKIP() << "Fuchsia can't load the test fixtures.";
#endif
  SkCodecs::Register(SkPngDecoder::Decoder());
  auto data = flutter::testing::OpenFixtureAsSkData("DisplayP3Logo.png");
  auto image = SkImages::DeferredFromEncodedData(data);
  std::shared_ptr<impeller::Capabilities> capabilities =
      impeller::CapabilitiesBuilder()
          .SetSupportsTextureToTextureBlits(true)
          .Build();
  ASSERT_TRUE(image != nullptr);
  ASSERT_EQ(SkISize::Make(100, 100), image->dimensions());
 
  ImageGeneratorRegistry registry;
  std::shared_ptr<ImageGenerator> generator =
      registry.CreateCompatibleGenerator(data);
  ASSERT_TRUE(generator);
 
  auto descriptor = fml::MakeRefCounted<ImageDescriptor>(std::move(data),
                                                         std::move(generator));
 
  ASSERT_FALSE(
      IsPngWithPLTE(descriptor->data()->bytes(), descriptor->data()->size()));
 
#if IMPELLER_SUPPORTS_RENDERING
  std::shared_ptr<impeller::Allocator> allocator =
      std::make_shared<impeller::TestImpellerAllocator>();
  absl::StatusOr<ImageDecoderImpeller::DecompressResult> wide_result =
      ImageDecoderImpeller::DecompressTexture(
          descriptor.get(), {.target_width = 100, .target_height = 100},
          {100, 100},
          /*supports_wide_gamut=*/true, capabilities, allocator);
  ASSERT_TRUE(wide_result.ok());
  ASSERT_EQ(wide_result->image_info.format,
            impeller::PixelFormat::kR16G16B16A16Float);
 
  const uint16_t* half_ptr = reinterpret_cast<const uint16_t*>(
      wide_result->device_buffer->OnGetContents());
  bool found_deep_red = false;
  for (int i = 0; i < wide_result->image_info.size.width *
                          wide_result->image_info.size.height;
       ++i) {
    float red = HalfToFloat(*half_ptr++);
    float green = HalfToFloat(*half_ptr++);
    float blue = HalfToFloat(*half_ptr++);
    half_ptr++;  // alpha
    if (fabsf(red - 1.0931f) < 0.01f && fabsf(green - -0.2268f) < 0.01f &&
        fabsf(blue - -0.1501f) < 0.01f) {
      found_deep_red = true;
      break;
    }
  }
 
  ASSERT_TRUE(found_deep_red);
  absl::StatusOr<ImageDecoderImpeller::DecompressResult> narrow_result =
      ImageDecoderImpeller::DecompressTexture(
          descriptor.get(), {.target_width = 100, .target_height = 100},
          {100, 100},
          /*supports_wide_gamut=*/false, capabilities, allocator);
 
  ASSERT_TRUE(narrow_result.ok());
  ASSERT_EQ(narrow_result->image_info.format,
            impeller::PixelFormat::kR8G8B8A8UNormInt);
#endif  // IMPELLER_SUPPORTS_RENDERING
}
 
TEST(ImageDecoderNoGLTest, ImpellerWideGamutIndexedPng) {
#if defined(OS_FUCHSIA)
  GTEST_SKIP() << "Fuchsia can't load the test fixtures.";
#endif
  SkCodecs::Register(SkPngDecoder::Decoder());
  auto data = flutter::testing::OpenFixtureAsSkData("WideGamutIndexed.png");
  auto image = SkImages::DeferredFromEncodedData(data);
  std::shared_ptr<impeller::Capabilities> capabilities =
      impeller::CapabilitiesBuilder()
          .SetSupportsTextureToTextureBlits(true)
          .Build();
  ASSERT_TRUE(image != nullptr);
  ASSERT_EQ(SkISize::Make(100, 100), image->dimensions());
 
  ImageGeneratorRegistry registry;
  std::shared_ptr<ImageGenerator> generator =
      registry.CreateCompatibleGenerator(data);
  ASSERT_TRUE(generator);
 
  auto descriptor = fml::MakeRefCounted<ImageDescriptor>(std::move(data),
                                                         std::move(generator));
 
  ASSERT_TRUE(
      IsPngWithPLTE(descriptor->data()->bytes(), descriptor->data()->size()));
 
#if IMPELLER_SUPPORTS_RENDERING
  std::shared_ptr<impeller::Allocator> allocator =
      std::make_shared<impeller::TestImpellerAllocator>();
  absl::StatusOr<ImageDecoderImpeller::DecompressResult> wide_result =
      ImageDecoderImpeller::DecompressTexture(
          descriptor.get(), {.target_width = 100, .target_height = 100},
          {100, 100},
          /*supports_wide_gamut=*/true, capabilities, allocator);
  ASSERT_TRUE(wide_result.ok());
  ASSERT_EQ(wide_result->image_info.format,
            impeller::PixelFormat::kB10G10R10XR);
 
  const uint32_t* pixel_ptr = reinterpret_cast<const uint32_t*>(
      wide_result->device_buffer->OnGetContents());
  bool found_deep_red = false;
  for (int i = 0; i < wide_result->image_info.size.width *
                          wide_result->image_info.size.height;
       ++i) {
    uint32_t pixel = *pixel_ptr++;
    float blue = DecodeBGR10((pixel >> 0) & 0x3ff);
    float green = DecodeBGR10((pixel >> 10) & 0x3ff);
    float red = DecodeBGR10((pixel >> 20) & 0x3ff);
    if (fabsf(red - 1.0931f) < 0.01f && fabsf(green - -0.2268f) < 0.01f &&
        fabsf(blue - -0.1501f) < 0.01f) {
      found_deep_red = true;
      break;
    }
  }
 
  ASSERT_TRUE(found_deep_red);
  absl::StatusOr<ImageDecoderImpeller::DecompressResult> narrow_result =
      ImageDecoderImpeller::DecompressTexture(
          descriptor.get(), {.target_width = 100, .target_height = 100},
          {100, 100},
          /*supports_wide_gamut=*/false, capabilities, allocator);
 
  ASSERT_TRUE(narrow_result.ok());
  ASSERT_EQ(narrow_result->image_info.format,
            impeller::PixelFormat::kR8G8B8A8UNormInt);
#endif  // IMPELLER_SUPPORTS_RENDERING
}
 
TEST(ImageDecoderNoGLTest, ImpellerRGBA32FDecode) {
#if defined(OS_FUCHSIA)
  GTEST_SKIP() << "Fuchsia can't load the test fixtures.";
#endif
 
#if IMPELLER_SUPPORTS_RENDERING
  // 1. Create a 1x1 pixel with float RGBA values.
  float pixel_data[] = {1.0f, 0.5f, 0.25f, 1.0f};  // R, G, B, A
  sk_sp<SkData> sk_data = SkData::MakeWithCopy(pixel_data, sizeof(pixel_data));
  auto immutable_buffer =
      fml::MakeRefCounted<ImmutableBuffer>(std::move(sk_data));
 
  // 2. Create an ImageDescriptor using the private constructor.
  ImageDescriptor::ImageInfo image_info = {
      .width = 1,
      .height = 1,
      .format = ImageDescriptor::PixelFormat::kRGBAFloat32,
      .alpha_type = kUnpremul_SkAlphaType,
  };
  auto descriptor = fml::MakeRefCounted<ImageDescriptor>(
      immutable_buffer->data(), image_info, sizeof(pixel_data));
 
  // Set up Impeller capabilities and allocator.
  std::shared_ptr<impeller::Capabilities> capabilities =
      impeller::CapabilitiesBuilder()
          .SetSupportsTextureToTextureBlits(true)
          .Build();
  std::shared_ptr<impeller::Allocator> allocator =
      std::make_shared<impeller::TestImpellerAllocator>();
 
  // 3. Call ImageDecoderImpeller::DecompressTexture with this ImageDescriptor.
  absl::StatusOr<ImageDecoderImpeller::DecompressResult> result =
      ImageDecoderImpeller::DecompressTexture(
          descriptor.get(),
          /*options=*/
          {.target_width = 1,
           .target_height = 1,
           .target_format =
               ImageDecoder::TargetPixelFormat::kR32G32B32A32Float},
          /*max_texture_size=*/{1, 1},
          /*supports_wide_gamut=*/true, capabilities, allocator);
 
  // 4. Assert that wide_result->image_info.format is
  // impeller::PixelFormat::kR32G32B32A32Float.
  ASSERT_TRUE(result.ok());
  ASSERT_EQ(result->image_info.format,
            impeller::PixelFormat::kR32G32B32A32Float);
 
  // Optionally, verify the pixel data if needed.
  const float* decompressed_pixel_ptr =
      reinterpret_cast<const float*>(result->device_buffer->OnGetContents());
  ASSERT_NE(decompressed_pixel_ptr, nullptr);
  EXPECT_EQ(decompressed_pixel_ptr[0], 1.0f);   // R
  EXPECT_EQ(decompressed_pixel_ptr[1], 0.5f);   // G
  EXPECT_EQ(decompressed_pixel_ptr[2], 0.25f);  // B
  EXPECT_EQ(decompressed_pixel_ptr[3], 1.0f);   // A
 
#endif  // IMPELLER_SUPPORTS_RENDERING
}
 
TEST(ImageDecoderNoGLTest, ImpellerR32FDecode) {
#if defined(OS_FUCHSIA)
  GTEST_SKIP() << "Fuchsia can't load the test fixtures.";
#endif
 
#if !IMPELLER_SUPPORTS_RENDERING
  GTEST_SKIP() << "test only supported on impeller";
#else
  // 1. Create a 1x1 pixel with float RGBA values.
  float pixel_data[] = {1.0f};
  sk_sp<SkData> sk_data = SkData::MakeWithCopy(pixel_data, sizeof(pixel_data));
  auto immutable_buffer =
      fml::MakeRefCounted<ImmutableBuffer>(std::move(sk_data));
 
  // 2. Create an ImageDescriptor using the private constructor.
  ImageDescriptor::ImageInfo image_info = {
      .width = 1,
      .height = 1,
      .format = ImageDescriptor::PixelFormat::kR32Float,
      .alpha_type = kUnpremul_SkAlphaType,
  };
  auto descriptor = fml::MakeRefCounted<ImageDescriptor>(
      immutable_buffer->data(), image_info, sizeof(pixel_data));
 
  // Set up Impeller capabilities and allocator.
  std::shared_ptr<impeller::Capabilities> capabilities =
      impeller::CapabilitiesBuilder()
          .SetSupportsTextureToTextureBlits(true)
          .Build();
  std::shared_ptr<impeller::Allocator> allocator =
      std::make_shared<impeller::TestImpellerAllocator>();
 
  // 3. Call ImageDecoderImpeller::DecompressTexture with this ImageDescriptor.
  absl::StatusOr<ImageDecoderImpeller::DecompressResult> result =
      ImageDecoderImpeller::DecompressTexture(
          descriptor.get(),
          /*options=*/
          {.target_width = 1,
           .target_height = 1,
           .target_format = ImageDecoder::TargetPixelFormat::kR32Float},
          /*max_texture_size=*/{1, 1},
          /*supports_wide_gamut=*/true, capabilities, allocator);
 
  // 4. Assert that wide_result->image_info.format is
  // impeller::PixelFormat::kR32G32B32A32Float.
  ASSERT_TRUE(result.ok());
  ASSERT_EQ(result->image_info.format, impeller::PixelFormat::kR32Float);
 
  // Optionally, verify the pixel data if needed.
  const float* decompressed_pixel_ptr =
      reinterpret_cast<const float*>(result->device_buffer->OnGetContents());
  ASSERT_NE(decompressed_pixel_ptr, nullptr);
  EXPECT_EQ(decompressed_pixel_ptr[0], 1.0f);
 
#endif  // IMPELLER_SUPPORTS_RENDERING
}
 
TEST(ImageDecoderNoGLTest, ImpellerUnmultipliedAlphaPng) {
#if defined(OS_FUCHSIA)
  GTEST_SKIP() << "Fuchsia can't load the test fixtures.";
#endif
  SkCodecs::Register(SkPngDecoder::Decoder());
  auto data = flutter::testing::OpenFixtureAsSkData("unmultiplied_alpha.png");
  auto image = SkImages::DeferredFromEncodedData(data);
  std::shared_ptr<impeller::Capabilities> capabilities =
      impeller::CapabilitiesBuilder()
          .SetSupportsTextureToTextureBlits(true)
          .Build();
  ASSERT_TRUE(image != nullptr);
  ASSERT_EQ(SkISize::Make(11, 11), image->dimensions());
 
  ImageGeneratorRegistry registry;
  std::shared_ptr<ImageGenerator> generator =
      registry.CreateCompatibleGenerator(data);
  ASSERT_TRUE(generator);
 
  auto descriptor = fml::MakeRefCounted<ImageDescriptor>(std::move(data),
                                                         std::move(generator));
 
#if IMPELLER_SUPPORTS_RENDERING
  std::shared_ptr<impeller::Allocator> allocator =
      std::make_shared<impeller::TestImpellerAllocator>();
  absl::StatusOr<ImageDecoderImpeller::DecompressResult> result =
      ImageDecoderImpeller::DecompressTexture(
          descriptor.get(), {.target_width = 11, .target_height = 11}, {11, 11},
          /*supports_wide_gamut=*/true, capabilities, allocator);
  ASSERT_TRUE(result.ok());
  ASSERT_EQ(result->image_info.format,
            impeller::PixelFormat::kR8G8B8A8UNormInt);
 
  const uint32_t* pixel_ptr =
      reinterpret_cast<const uint32_t*>(result->device_buffer->OnGetContents());
  // Test the upper left pixel is premultiplied and not solid red.
  ASSERT_EQ(*pixel_ptr, (uint32_t)0x1000001);
  // Test a pixel in the green box is still green.
  ASSERT_EQ(*(pixel_ptr + 11 * 4 + 4), (uint32_t)0xFF00FF00);
 
#endif  // IMPELLER_SUPPORTS_RENDERING
}
 
}  // namespace testing
}  // namespace flutter