content/browser/background_fetch/storage/image_helpers.cc

// Copyright 2018 The Chromium Authors
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.

#include "content/browser/background_fetch/storage/image_helpers.h"

#include "base/functional/bind.h"
#include "base/memory/ref_counted_memory.h"
#include "base/strings/string_view_util.h"
#include "base/task/sequenced_task_runner.h"
#include "base/task/task_traits.h"
#include "base/task/thread_pool.h"
#include "ui/gfx/image/image.h"

namespace content {
namespace background_fetch {

namespace {

// The max icon resolution, this is used as a threshold to decide
// whether the icon should be persisted.
constexpr int kMaxIconResolution = 256 * 256;

std::string ConvertAndSerializeIcon(const SkBitmap& icon) {
  auto icon_bytes = gfx::Image::CreateFrom1xBitmap(icon).As1xPNGBytes();
  return std::string(base::as_string_view(*icon_bytes));
}

SkBitmap DeserializeAndConvertIcon(
    std::unique_ptr<std::string> serialized_icon) {
  return gfx::Image::CreateFrom1xPNGBytes(base::as_byte_span(*serialized_icon))
      .AsBitmap();
}

}  // namespace

bool ShouldPersistIcon(const SkBitmap& icon) {
  return !icon.isNull() && (icon.height() * icon.width() <= kMaxIconResolution);
}

void SerializeIcon(const SkBitmap& icon, SerializeIconCallback callback) {
  DCHECK(!icon.isNull());
  // Do the serialization on a seperate thread to avoid blocking on
  // expensive operations (image conversions), then post back to current
  // thread and continue normally.
  base::ThreadPool::PostTaskAndReplyWithResult(
      FROM_HERE,
      {base::MayBlock(), base::TaskShutdownBehavior::SKIP_ON_SHUTDOWN,
       base::TaskPriority::BEST_EFFORT},
      base::BindOnce(&ConvertAndSerializeIcon, icon), std::move(callback));
}

void DeserializeIcon(std::unique_ptr<std::string> serialized_icon,
                     DeserializeIconCallback callback) {
  DCHECK(serialized_icon);
  // Do the deserialization on a seperate thread to avoid blocking on
  // expensive operations (image conversions), then post back to current
  // thread and continue normally.
  base::ThreadPool::PostTaskAndReplyWithResult(
      FROM_HERE,
      {base::MayBlock(), base::TaskShutdownBehavior::SKIP_ON_SHUTDOWN,
       base::TaskPriority::BEST_EFFORT},
      base::BindOnce(&DeserializeAndConvertIcon, std::move(serialized_icon)),
      std::move(callback));
}

}  // namespace background_fetch
}  // namespace content