tor-browser

The Tor Browser
git clone https://git.dasho.dev/tor-browser.git
Log | Files | Refs | README | LICENSE

ImageUtils.h (1869B)


      1 /* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
      2 /* vim:set ts=2 sw=2 sts=2 et cindent: */
      3 /* This Source Code Form is subject to the terms of the Mozilla Public
      4 * License, v. 2.0. If a copy of the MPL was not distributed with this
      5 * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
      6 
      7 #ifndef mozilla_dom_ImageBitmapFormatUtils_h
      8 #define mozilla_dom_ImageBitmapFormatUtils_h
      9 
     10 #include <cstdint>
     11 
     12 #include "nsTArrayForwardDeclare.h"
     13 
     14 namespace mozilla {
     15 
     16 template <typename T>
     17 class Maybe;
     18 
     19 namespace layers {
     20 class Image;
     21 }
     22 
     23 class ErrorResult;
     24 
     25 namespace dom {
     26 
     27 struct ChannelPixelLayout;
     28 enum class ImageBitmapFormat : uint8_t;
     29 
     30 typedef nsTArray<ChannelPixelLayout> ImagePixelLayout;
     31 
     32 /*
     33 * ImageUtils is a wrapper around layers::Image. It provides three unified
     34 * methods to all sub-classes of layers::Image, which are:
     35 *
     36 * (1) GetFormat() converts the image's format into ImageBitmapFormat enum.
     37 * (2) GetBufferLength() returns the number of bytes that are used to store
     38 *     the image's underlying raw data.
     39 *
     40 * In theory, the functionalities of this class could be merged into the
     41 * interface of layers::Image. However, this is designed as a isolated wrapper
     42 * because we don't want to pollute the layers::Image's interface with methods
     43 * that are only meaningful to the ImageBitmap.
     44 */
     45 class ImageUtils {
     46 public:
     47  class Impl;
     48  ImageUtils() = delete;
     49  ImageUtils(const ImageUtils&) = delete;
     50  ImageUtils(ImageUtils&&) = delete;
     51  ImageUtils& operator=(const ImageUtils&) = delete;
     52  ImageUtils& operator=(ImageUtils&&) = delete;
     53 
     54  explicit ImageUtils(layers::Image* aImage);
     55  ~ImageUtils();
     56 
     57  Maybe<ImageBitmapFormat> GetFormat() const;
     58 
     59  uint32_t GetBufferLength() const;
     60 
     61 protected:
     62  Impl* mImpl;
     63 };
     64 
     65 }  // namespace dom
     66 }  // namespace mozilla
     67 
     68 #endif /* mozilla_dom_ImageBitmapFormatUtils_h */