| // Copyright 2018 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 "chrome/browser/download/thumbnail_util.h" |
| |
| #include "base/bind.h" |
| #include "base/logging.h" |
| #include "base/task/post_task.h" |
| #include "content/public/browser/browser_thread.h" |
| #include "skia/ext/image_operations.h" |
| |
| namespace { |
| |
| SkBitmap ScaleDownBitmapOnIOThread(int icon_size, SkBitmap bitmap) { |
| DCHECK(!content::BrowserThread::CurrentlyOn(content::BrowserThread::UI)); |
| |
| if (bitmap.drawsNothing()) |
| return bitmap; |
| |
| // Shrink the image down so that its smallest dimension is equal to or |
| // smaller than the requested size. |
| int min_dimension = std::min(bitmap.width(), bitmap.height()); |
| |
| if (min_dimension <= icon_size) |
| return bitmap; |
| |
| uint64_t width = static_cast<uint64_t>(bitmap.width()); |
| uint64_t height = static_cast<uint64_t>(bitmap.height()); |
| return skia::ImageOperations::Resize( |
| bitmap, skia::ImageOperations::RESIZE_BEST, |
| width * icon_size / min_dimension, height * icon_size / min_dimension); |
| } |
| |
| } // namespace |
| |
| void ScaleDownBitmap(int icon_size, |
| const SkBitmap& bitmap, |
| base::OnceCallback<void(SkBitmap)> callback) { |
| DCHECK(callback); |
| DCHECK(content::BrowserThread::CurrentlyOn(content::BrowserThread::UI)); |
| |
| // Scale down bitmap on another thread. |
| base::PostTaskWithTraitsAndReplyWithResult( |
| FROM_HERE, {base::MayBlock(), base::TaskPriority::USER_BLOCKING}, |
| base::BindOnce(&ScaleDownBitmapOnIOThread, icon_size, std::move(bitmap)), |
| std::move(callback)); |
| } |