image/DecoderFactory.h

   1 /* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*-
   2  *
   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_image_DecoderFactory_h
   8 #define mozilla_image_DecoderFactory_h
   9
  10 #include "DecoderFlags.h"
  11 #include "mozilla/Attributes.h"
  12 #include "mozilla/Maybe.h"
  13 #include "mozilla/NotNull.h"
  14 #include "mozilla/gfx/2D.h"
  15 #include "nsCOMPtr.h"
  16 #include "SurfaceFlags.h"
  17
  18 namespace mozilla {
  19 namespace image {
  20
  21 class Decoder;
  22 class IDecodingTask;
  23 class nsICODecoder;
  24 class RasterImage;
  25 class SourceBuffer;
  26 class SourceBufferIterator;
  27
  28 /**
  29  * The type of decoder; this is usually determined from a MIME type using
  30  * DecoderFactory::GetDecoderType().
  31  */
  32 enum class DecoderType {
  33   PNG,
  34   GIF,
  35   JPEG,
  36   BMP,
  37   BMP_CLIPBOARD,
  38   ICO,
  39   ICON,
  40   WEBP,
  41   UNKNOWN
  42 };
  43
  44 class DecoderFactory {
  45  public:
  46   /// @return the type of decoder which is appropriate for @aMimeType.
  47   static DecoderType GetDecoderType(const char* aMimeType);
  48
  49   /**
  50    * Creates and initializes a decoder for non-animated images of type @aType.
  51    * (If the image *is* animated, only the first frame will be decoded.) The
  52    * decoder will send notifications to @aImage.
  53    *
  54    * @param aType Which type of decoder to create - JPEG, PNG, etc.
  55    * @param aImage The image will own the decoder and which should receive
  56    *               notifications as decoding progresses.
  57    * @param aSourceBuffer The SourceBuffer which the decoder will read its data
  58    *                      from.
  59    * @param aIntrinsicSize The intrinsic size of the image, normally obtained
  60    *                       during the metadata decode.
  61    * @param aOutputSize The output size for the decoder. If this is smaller than
  62    *                    the intrinsic size, the decoder will downscale the
  63    *                    image.
  64    * @param aDecoderFlags Flags specifying the behavior of this decoder.
  65    * @param aSurfaceFlags Flags specifying the type of output this decoder
  66    *                      should produce.
  67    * @param aOutTask Task representing the decoder.
  68    * @return NS_OK if the decoder has been created/initialized successfully;
  69    *         NS_ERROR_ALREADY_INITIALIZED if there is already an active decoder
  70    *           for this image;
  71    *         Else some other unrecoverable error occurred.
  72    */
  73   static nsresult CreateDecoder(DecoderType aType, NotNull<RasterImage*> aImage,
  74                                 NotNull<SourceBuffer*> aSourceBuffer,
  75                                 const gfx::IntSize& aIntrinsicSize,
  76                                 const gfx::IntSize& aOutputSize,
  77                                 DecoderFlags aDecoderFlags,
  78                                 SurfaceFlags aSurfaceFlags,
  79                                 IDecodingTask** aOutTask);
  80
  81   /**
  82    * Creates and initializes a decoder for animated images of type @aType.
  83    * The decoder will send notifications to @aImage.
  84    *
  85    * @param aType Which type of decoder to create - JPEG, PNG, etc.
  86    * @param aImage The image will own the decoder and which should receive
  87    *               notifications as decoding progresses.
  88    * @param aSourceBuffer The SourceBuffer which the decoder will read its data
  89    *                      from.
  90    * @param aIntrinsicSize The intrinsic size of the image, normally obtained
  91    *                       during the metadata decode.
  92    * @param aDecoderFlags Flags specifying the behavior of this decoder.
  93    * @param aSurfaceFlags Flags specifying the type of output this decoder
  94    *                      should produce.
  95    * @param aCurrentFrame The current frame the decoder should auto advance to.
  96    * @param aOutTask Task representing the decoder.
  97    * @return NS_OK if the decoder has been created/initialized successfully;
  98    *         NS_ERROR_ALREADY_INITIALIZED if there is already an active decoder
  99    *           for this image;
 100    *         Else some other unrecoverable error occurred.
 101    */
 102   static nsresult CreateAnimationDecoder(
 103       DecoderType aType, NotNull<RasterImage*> aImage,
 104       NotNull<SourceBuffer*> aSourceBuffer, const gfx::IntSize& aIntrinsicSize,
 105       DecoderFlags aDecoderFlags, SurfaceFlags aSurfaceFlags,
 106       size_t aCurrentFrame, IDecodingTask** aOutTask);
 107
 108   /**
 109    * Creates and initializes a decoder for animated images, cloned from the
 110    * given decoder.
 111    *
 112    * @param aDecoder Decoder to clone.
 113    */
 114   static already_AddRefed<Decoder> CloneAnimationDecoder(Decoder* aDecoder);
 115
 116   /**
 117    * Creates and initializes a metadata decoder of type @aType. This decoder
 118    * will only decode the image's header, extracting metadata like the size of
 119    * the image. No actual image data will be decoded and no surfaces will be
 120    * allocated. The decoder will send notifications to @aImage.
 121    *
 122    * @param aType Which type of decoder to create - JPEG, PNG, etc.
 123    * @param aImage The image will own the decoder and which should receive
 124    *               notifications as decoding progresses.
 125    * @param aSourceBuffer The SourceBuffer which the decoder will read its data
 126    *                      from.
 127    */
 128   static already_AddRefed<IDecodingTask> CreateMetadataDecoder(
 129       DecoderType aType, NotNull<RasterImage*> aImage,
 130       NotNull<SourceBuffer*> aSourceBuffer);
 131
 132   /**
 133    * Creates and initializes a decoder for an ICO resource, which may be either
 134    * a BMP or PNG image.
 135    *
 136    * @param aType Which type of decoder to create. This must be either BMP or
 137    *              PNG.
 138    * @param aIterator The SourceBufferIterator which the decoder will read its
 139    *                  data from.
 140    * @param aICODecoder The ICO decoder which is controlling this resource
 141    *                    decoder. @aICODecoder's settings will be copied to the
 142    *                    resource decoder, so the two decoders will have the
 143    *                    same decoder flags, surface flags, target size, and
 144    *                    other parameters.
 145    * @param aIsMetadataDecode Indicates whether or not this decoder is for
 146    *                          metadata or not. Independent of the state of the
 147    *                          parent decoder.
 148    * @param aExpectedSize The expected size of the resource from the ICO header.
 149    * @param aDataOffset If @aType is BMP, specifies the offset at which data
 150    *                    begins in the BMP resource. Must be Some() if and only
 151    *                    if @aType is BMP.
 152    */
 153   static already_AddRefed<Decoder> CreateDecoderForICOResource(
 154       DecoderType aType, SourceBufferIterator&& aIterator,
 155       NotNull<nsICODecoder*> aICODecoder, bool aIsMetadataDecode,
 156       const Maybe<gfx::IntSize>& aExpectedSize,
 157       const Maybe<uint32_t>& aDataOffset = Nothing());
 158
 159   /**
 160    * Creates and initializes an anonymous decoder (one which isn't associated
 161    * with an Image object). Only the first frame of the image will be decoded.
 162    *
 163    * @param aType Which type of decoder to create - JPEG, PNG, etc.
 164    * @param aSourceBuffer The SourceBuffer which the decoder will read its data
 165    *                      from.
 166    * @param aOutputSize If Some(), the output size for the decoder. If this is
 167    *                    smaller than the intrinsic size, the decoder will
 168    *                    downscale the image. If Nothing(), the output size will
 169    *                    be the intrinsic size.
 170    * @param aDecoderFlags Flags specifying the behavior of this decoder.
 171    * @param aSurfaceFlags Flags specifying the type of output this decoder
 172    *                      should produce.
 173    */
 174   static already_AddRefed<Decoder> CreateAnonymousDecoder(
 175       DecoderType aType, NotNull<SourceBuffer*> aSourceBuffer,
 176       const Maybe<gfx::IntSize>& aOutputSize, DecoderFlags aDecoderFlags,
 177       SurfaceFlags aSurfaceFlags);
 178
 179   /**
 180    * Creates and initializes an anonymous metadata decoder (one which isn't
 181    * associated with an Image object). This decoder will only decode the image's
 182    * header, extracting metadata like the size of the image. No actual image
 183    * data will be decoded and no surfaces will be allocated.
 184    *
 185    * @param aType Which type of decoder to create - JPEG, PNG, etc.
 186    * @param aSourceBuffer The SourceBuffer which the decoder will read its data
 187    *                      from.
 188    */
 189   static already_AddRefed<Decoder> CreateAnonymousMetadataDecoder(
 190       DecoderType aType, NotNull<SourceBuffer*> aSourceBuffer);
 191
 192  private:
 193   virtual ~DecoderFactory() = 0;
 194
 195   /**
 196    * An internal method which allocates a new decoder of the requested @aType.
 197    */
 198   static already_AddRefed<Decoder> GetDecoder(DecoderType aType,
 199                                               RasterImage* aImage,
 200                                               bool aIsRedecode);
 201 };
 202
 203 }  // namespace image
 204 }  // namespace mozilla
 205
 206 #endif  // mozilla_image_DecoderFactory_h