dark_mode_image_classifier.cc | Explore in Territory

// Copyright 2019 The Chromium Authors
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.

#ifdef UNSAFE_BUFFERS_BUILD
// TODO(crbug.com/351564777): Remove this and convert code to safer constructs.
#pragma allow_unsafe_buffers
#endif

#include "third_party/blink/renderer/platform/graphics/dark_mode_image_classifier.h"

#include <optional>
#include <set>

#include "base/memory/singleton.h"
#include "third_party/blink/renderer/platform/graphics/dark_mode_settings.h"
#include "third_party/blink/renderer/platform/graphics/darkmode/darkmode_classifier.h"
#include "ui/gfx/geometry/size.h"

namespace blink {
namespace {

// Decision tree lower and upper thresholds for grayscale and color images.
const float kLowColorCountThreshold[2] = …;
const float kHighColorCountThreshold[2] = …;

bool IsColorGray(const SkColor& color) { … }

bool IsColorTransparent(const SkColor& color) { … }

const int kMaxSampledPixels = …;
const int kMaxBlocks = …;
const float kMinOpaquePixelPercentageForForeground = …;

}  // namespace

DarkModeImageClassifier::DarkModeImageClassifier(
    DarkModeImageClassifierPolicy image_classifier_policy)
    : … { … }

DarkModeImageClassifier::~DarkModeImageClassifier() = default;

DarkModeResult DarkModeImageClassifier::Classify(const SkPixmap& pixmap,
                                                 const SkIRect& src) const { … }

std::optional<DarkModeImageClassifier::Features>
DarkModeImageClassifier::GetFeatures(const SkPixmap& pixmap,
                                     const SkIRect& src) const { … }

// Extracts sample pixels from the image. The image is separated into uniformly
// distributed blocks through its width and height, each block is sampled, and
// checked to see if it seems to be background or foreground.
void DarkModeImageClassifier::GetSamples(const SkPixmap& pixmap,
                                         const SkIRect& src,
                                         std::vector<SkColor>* sampled_pixels,
                                         float* transparency_ratio,
                                         float* background_ratio) const { … }

// Selects samples at regular intervals from a block of the image.
// Returns the opaque sampled pixels, and the number of transparent
// sampled pixels.
void DarkModeImageClassifier::GetBlockSamples(
    const SkPixmap& pixmap,
    const SkIRect& block,
    const int required_samples_count,
    std::vector<SkColor>* sampled_pixels,
    int* transparent_pixels_count) const { … }

DarkModeImageClassifier::Features DarkModeImageClassifier::ComputeFeatures(
    const std::vector<SkColor>& sampled_pixels,
    const float transparency_ratio,
    const float background_ratio) const { … }

float DarkModeImageClassifier::ComputeColorBucketsRatio(
    const std::vector<SkColor>& sampled_pixels,
    const ColorMode color_mode) const { … }

DarkModeResult DarkModeImageClassifier::ClassifyWithFeatures(
    const Features& features) const { … }

DarkModeResult DarkModeImageClassifier::ClassifyUsingDecisionTree(
    const DarkModeImageClassifier::Features& features) const { … }

}  // namespace blink
chromium/third_party/blink/renderer/platform/graphics/dark_mode_image_classifier.cc
