Source code

Revision control

Line Code
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 161 162 163 164 165 166 167 168 169 170 171 172 173 174 175 176 177 178 179 180 181 182 183 184 185 186 187 188 189 190 191 192 193 194 195 196 197 198 199 200 201 202 203 204 205 206 207 208 209 210 211 212 213 214 215 216 217 218 219 220 221 222 223 224 225 226 227 228 229 230 231 232 233 234 235 236 237 238 239 240 241 242 243 244 245 246 247 248 249 250 251 252 253 254 255 256 257 258 259 260 261 262 263 264 265 266 267 268 269 270 271 272 273 274 275 276 277 278 279 280 281 282 283 284 285 286 287 288 289 290 291 292 293 294 295 296 297 298 299 300 301 302 303 304 305 306 307 308 309 310 311 312 313 314 315 316 317 318 319 320 321 322 323 324 325 326 327 328 329 330 331 332 333 334 335 336 337 338 339 340 341 342 343 344 345 346 347 348 349 350 351 352 353 354 355 356 357 358 359 360 361 362 363 364 365 366 367 368 369 370 371 372 373 374 375 376 377 378 379 380 381 382 383 384 385 386 387 388 389 390 391 392 393 394 395 396 397 398 399 400 401 402 403 404 405 406 407 408 409 410 411 412 413 414 415 416 417 418 419 420 421 422 423 424 425 426 427 428 429 430 431 432 433 434 435 436 437 438 439 440 441 442 443 444 445 446 447 448 449 450 451 452 453 454 455 456 457 458 459 460 461 462 463 464 465 466 467 468 469 470 471 472 473 474 475 476 477 478 479
/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*-
 *
 * This Source Code Form is subject to the terms of the Mozilla Public
 * License, v. 2.0. If a copy of the MPL was not distributed with this
 * file, You can obtain one at http://mozilla.org/MPL/2.0/. */

/** @file
 * This file declares the RasterImage class, which
 * handles static and animated rasterized images.
 *
 * @author  Stuart Parmenter <pavlov@netscape.com>
 * @author  Chris Saari <saari@netscape.com>
 * @author  Arron Mogge <paper@animecity.nu>
 * @author  Andrew Smith <asmith15@learn.senecac.on.ca>
 */

#ifndef mozilla_image_RasterImage_h
#define mozilla_image_RasterImage_h

#include "Image.h"
#include "nsCOMPtr.h"
#include "imgIContainer.h"
#include "nsIProperties.h"
#include "nsTArray.h"
#include "LookupResult.h"
#include "nsThreadUtils.h"
#include "DecoderFactory.h"
#include "FrameAnimator.h"
#include "ImageMetadata.h"
#include "ISurfaceProvider.h"
#include "Orientation.h"
#include "nsIObserver.h"
#include "mozilla/Attributes.h"
#include "mozilla/Maybe.h"
#include "mozilla/MemoryReporting.h"
#include "mozilla/NotNull.h"
#include "mozilla/TimeStamp.h"
#include "mozilla/WeakPtr.h"
#include "mozilla/UniquePtr.h"
#include "ImageContainer.h"
#include "PlaybackType.h"
#ifdef DEBUG
#  include "imgIContainerDebug.h"
#endif

class nsIInputStream;
class nsIRequest;

#define NS_RASTERIMAGE_CID                           \
  { /* 376ff2c1-9bf6-418a-b143-3340c00112f7 */       \
    0x376ff2c1, 0x9bf6, 0x418a, {                    \
      0xb1, 0x43, 0x33, 0x40, 0xc0, 0x01, 0x12, 0xf7 \
    }                                                \
  }

/**
 * Handles static and animated image containers.
 *
 *
 * @par A Quick Walk Through
 * The decoder initializes this class and calls AppendFrame() to add a frame.
 * Once RasterImage detects more than one frame, it starts the animation
 * with StartAnimation(). Note that the invalidation events for RasterImage are
 * generated automatically using nsRefreshDriver.
 *
 * @par
 * StartAnimation() initializes the animation helper object and sets the time
 * the first frame was displayed to the current clock time.
 *
 * @par
 * When the refresh driver corresponding to the imgIContainer that this image is
 * a part of notifies the RasterImage that it's time to invalidate,
 * RequestRefresh() is called with a given TimeStamp to advance to. As long as
 * the timeout of the given frame (the frame's "delay") plus the time that frame
 * was first displayed is less than or equal to the TimeStamp given,
 * RequestRefresh() calls AdvanceFrame().
 *
 * @par
 * AdvanceFrame() is responsible for advancing a single frame of the animation.
 * It can return true, meaning that the frame advanced, or false, meaning that
 * the frame failed to advance (usually because the next frame hasn't been
 * decoded yet). It is also responsible for performing the final animation stop
 * procedure if the final frame of a non-looping animation is reached.
 *
 * @par
 * Each frame can have a different method of removing itself. These are
 * listed as imgIContainer::cDispose... constants.  Notify() calls
 * DoComposite() to handle any special frame destruction.
 *
 * @par
 * The basic path through DoComposite() is:
 * 1) Calculate Area that needs updating, which is at least the area of
 *    aNextFrame.
 * 2) Dispose of previous frame.
 * 3) Draw new image onto compositingFrame.
 * See comments in DoComposite() for more information and optimizations.
 *
 * @par
 * The rest of the RasterImage specific functions are used by DoComposite to
 * destroy the old frame and build the new one.
 *
 * @note
 * <li> "Mask", "Alpha", and "Alpha Level" are interchangeable phrases in
 * respects to RasterImage.
 *
 * @par
 * <li> GIFs never have more than a 1 bit alpha.
 * <li> APNGs may have a full alpha channel.
 *
 * @par
 * <li> Background color specified in GIF is ignored by web browsers.
 *
 * @par
 * <li> If Frame 3 wants to dispose by restoring previous, what it wants is to
 * restore the composition up to and including Frame 2, as well as Frame 2s
 * disposal.  So, in the middle of DoComposite when composing Frame 3, right
 * after destroying Frame 2's area, we copy compositingFrame to
 * prevCompositingFrame.  When DoComposite gets called to do Frame 4, we
 * copy prevCompositingFrame back, and then draw Frame 4 on top.
 *
 * @par
 * The mAnim structure has members only needed for animated images, so
 * it's not allocated until the second frame is added.
 */

namespace mozilla {

namespace layers {
class ImageContainer;
class Image;
class LayersManager;
}  // namespace layers

namespace image {

class Decoder;
struct DecoderFinalStatus;
struct DecoderTelemetry;
class ImageMetadata;
class SourceBuffer;

class RasterImage final : public ImageResource,
                          public nsIProperties,
                          public SupportsWeakPtr<RasterImage>
#ifdef DEBUG
    ,
                          public imgIContainerDebug
#endif
{
  // (no public constructor - use ImageFactory)
  virtual ~RasterImage();

 public:
  MOZ_DECLARE_WEAKREFERENCE_TYPENAME(RasterImage)
  NS_DECL_THREADSAFE_ISUPPORTS
  NS_DECL_NSIPROPERTIES
  NS_DECL_IMGICONTAINER
#ifdef DEBUG
  NS_DECL_IMGICONTAINERDEBUG
#endif

  nsresult GetNativeSizes(nsTArray<gfx::IntSize>& aNativeSizes) const override;
  size_t GetNativeSizesLength() const override;
  virtual nsresult StartAnimation() override;
  virtual nsresult StopAnimation() override;

  // Methods inherited from Image
  virtual void OnSurfaceDiscarded(const SurfaceKey& aSurfaceKey) override;

  virtual size_t SizeOfSourceWithComputedFallback(
      SizeOfState& aState) const override;
  virtual void CollectSizeOfSurfaces(nsTArray<SurfaceMemoryCounter>& aCounters,
                                     MallocSizeOf aMallocSizeOf) const override;

  /* Triggers discarding. */
  void Discard();

  //////////////////////////////////////////////////////////////////////////////
  // Decoder callbacks.
  //////////////////////////////////////////////////////////////////////////////

  /**
   * Sends the provided progress notifications to ProgressTracker.
   *
   * Main-thread only.
   *
   * @param aProgress    The progress notifications to send.
   * @param aInvalidRect An invalidation rect to send.
   * @param aFrameCount  If Some(), an updated count of the number of frames of
   *                     animation the decoder has finished decoding so far.
   *                     This is a lower bound for the total number of
   *                     animation frames this image has.
   * @param aDecoderFlags The decoder flags used by the decoder that generated
   *                      these notifications, or DefaultDecoderFlags() if the
   *                      notifications don't come from a decoder.
   * @param aSurfaceFlags The surface flags used by the decoder that generated
   *                      these notifications, or DefaultSurfaceFlags() if the
   *                      notifications don't come from a decoder.
   */
  void NotifyProgress(Progress aProgress,
                      const gfx::IntRect& aInvalidRect = nsIntRect(),
                      const Maybe<uint32_t>& aFrameCount = Nothing(),
                      DecoderFlags aDecoderFlags = DefaultDecoderFlags(),
                      SurfaceFlags aSurfaceFlags = DefaultSurfaceFlags());

  /**
   * Records decoding results, sends out any final notifications, updates the
   * state of this image, and records telemetry.
   *
   * Main-thread only.
   *
   * @param aStatus       Final status information about the decoder. (Whether
   * it encountered an error, etc.)
   * @param aMetadata     Metadata about this image that the decoder gathered.
   * @param aTelemetry    Telemetry data about the decoder.
   * @param aProgress     Any final progress notifications to send.
   * @param aInvalidRect  Any final invalidation rect to send.
   * @param aFrameCount   If Some(), a final updated count of the number of
   * frames of animation the decoder has finished decoding so far. This is a
   * lower bound for the total number of animation frames this image has.
   * @param aDecoderFlags The decoder flags used by the decoder.
   * @param aSurfaceFlags The surface flags used by the decoder.
   */
  void NotifyDecodeComplete(
      const DecoderFinalStatus& aStatus, const ImageMetadata& aMetadata,
      const DecoderTelemetry& aTelemetry, Progress aProgress,
      const gfx::IntRect& aInvalidRect, const Maybe<uint32_t>& aFrameCount,
      DecoderFlags aDecoderFlags, SurfaceFlags aSurfaceFlags);

  // Helper method for NotifyDecodeComplete.
  void ReportDecoderError();

  //////////////////////////////////////////////////////////////////////////////
  // Network callbacks.
  //////////////////////////////////////////////////////////////////////////////

  virtual nsresult OnImageDataAvailable(nsIRequest* aRequest,
                                        nsISupports* aContext,
                                        nsIInputStream* aInStr,
                                        uint64_t aSourceOffset,
                                        uint32_t aCount) override;
  virtual nsresult OnImageDataComplete(nsIRequest* aRequest,
                                       nsISupports* aContext, nsresult aStatus,
                                       bool aLastPart) override;

  void NotifyForLoadEvent(Progress aProgress);

  /**
   * A hint of the number of bytes of source data that the image contains. If
   * called early on, this can help reduce copying and reallocations by
   * appropriately preallocating the source data buffer.
   *
   * We take this approach rather than having the source data management code do
   * something more complicated (like chunklisting) because HTTP is by far the
   * dominant source of images, and the Content-Length header is quite reliable.
   * Thus, pre-allocation simplifies code and reduces the total number of
   * allocations.
   */
  nsresult SetSourceSizeHint(uint32_t aSizeHint);

  nsCString GetURIString() {
    nsCString spec;
    if (GetURI()) {
      GetURI()->GetSpec(spec);
    }
    return spec;
  }

 private:
  nsresult Init(const char* aMimeType, uint32_t aFlags);

  /**
   * Tries to retrieve a surface for this image with size @aSize, surface flags
   * matching @aFlags, and a playback type of @aPlaybackType.
   *
   * If @aFlags specifies FLAG_SYNC_DECODE and we already have all the image
   * data, we'll attempt a sync decode if no matching surface is found. If
   * FLAG_SYNC_DECODE was not specified and no matching surface was found, we'll
   * kick off an async decode so that the surface is (hopefully) available next
   * time it's requested. aMarkUsed determines if we mark the surface used in
   * the surface cache or not.
   *
   * @return a drawable surface, which may be empty if the requested surface
   *         could not be found.
   */
  LookupResult LookupFrame(const gfx::IntSize& aSize, uint32_t aFlags,
                           PlaybackType aPlaybackType, bool aMarkUsed);

  /// Helper method for LookupFrame().
  LookupResult LookupFrameInternal(const gfx::IntSize& aSize, uint32_t aFlags,
                                   PlaybackType aPlaybackType, bool aMarkUsed);

  ImgDrawResult DrawInternal(DrawableSurface&& aFrameRef, gfxContext* aContext,
                             const nsIntSize& aSize, const ImageRegion& aRegion,
                             gfx::SamplingFilter aSamplingFilter,
                             uint32_t aFlags, float aOpacity);

  Tuple<ImgDrawResult, gfx::IntSize, RefPtr<gfx::SourceSurface>>
  GetFrameInternal(const gfx::IntSize& aSize,
                   const Maybe<SVGImageContext>& aSVGContext,
                   uint32_t aWhichFrame, uint32_t aFlags) override;

  Tuple<ImgDrawResult, gfx::IntSize> GetImageContainerSize(
      layers::LayerManager* aManager, const gfx::IntSize& aSize,
      uint32_t aFlags) override;

  //////////////////////////////////////////////////////////////////////////////
  // Decoding.
  //////////////////////////////////////////////////////////////////////////////

  /**
   * Creates and runs a decoder, either synchronously or asynchronously
   * according to @aFlags. Decodes at the provided target size @aSize, using
   * decode flags @aFlags. Performs a single-frame decode of this image unless
   * we know the image is animated *and* @aPlaybackType is
   * PlaybackType::eAnimated.
   *
   * It's an error to call Decode() before this image's intrinsic size is
   * available. A metadata decode must successfully complete first.
   *
   * Returns true of the decode was run synchronously.
   */
  bool Decode(const gfx::IntSize& aSize, uint32_t aFlags,
              PlaybackType aPlaybackType);

  /**
   * Creates and runs a metadata decoder, either synchronously or
   * asynchronously according to @aFlags.
   */
  NS_IMETHOD DecodeMetadata(uint32_t aFlags);

  /**
   * Sets the size, inherent orientation, animation metadata, and other
   * information about the image gathered during decoding.
   *
   * This function may be called multiple times, but will throw an error if
   * subsequent calls do not match the first.
   *
   * @param aMetadata The metadata to set on this image.
   * @param aFromMetadataDecode True if this metadata came from a metadata
   *                            decode; false if it came from a full decode.
   * @return |true| unless a catastrophic failure was discovered. If |false| is
   * returned, it indicates that the image is corrupt in a way that requires all
   * surfaces to be discarded to recover.
   */
  bool SetMetadata(const ImageMetadata& aMetadata, bool aFromMetadataDecode);

  /**
   * In catastrophic circumstances like a GPU driver crash, the contents of our
   * frames may become invalid.  If the information we gathered during the
   * metadata decode proves to be wrong due to image corruption, the frames we
   * have may violate this class's invariants. Either way, we need to
   * immediately discard the invalid frames and redecode so that callers don't
   * perceive that we've entered an invalid state.
   *
   * RecoverFromInvalidFrames discards all existing frames and redecodes using
   * the provided @aSize and @aFlags.
   */
  void RecoverFromInvalidFrames(const nsIntSize& aSize, uint32_t aFlags);

  void OnSurfaceDiscardedInternal(bool aAnimatedFramesDiscarded);

 private:  // data
  nsIntSize mSize;
  nsTArray<nsIntSize> mNativeSizes;
  Orientation mOrientation;

  /// If this has a value, we're waiting for SetSize() to send the load event.
  Maybe<Progress> mLoadProgress;

  nsCOMPtr<nsIProperties> mProperties;

  /// If this image is animated, a FrameAnimator which manages its animation.
  UniquePtr<FrameAnimator> mFrameAnimator;

  /// Animation timeline and other state for animation images.
  Maybe<AnimationState> mAnimationState;

  // Image locking.
  uint32_t mLockCount;

  // The type of decoder this image needs. Computed from the MIME type in
  // Init().
  DecoderType mDecoderType;

  // How many times we've decoded this image.
  // This is currently only used for statistics
  int32_t mDecodeCount;

#ifdef DEBUG
  uint32_t mFramesNotified;
#endif

  // The source data for this image.
  NotNull<RefPtr<SourceBuffer>> mSourceBuffer;

  // Boolean flags (clustered together to conserve space):
  bool mHasSize : 1;         // Has SetSize() been called?
  bool mTransient : 1;       // Is the image short-lived?
  bool mSyncLoad : 1;        // Are we loading synchronously?
  bool mDiscardable : 1;     // Is container discardable?
  bool mSomeSourceData : 1;  // Do we have some source data?
  bool mAllSourceData : 1;   // Do we have all the source data?
  bool mHasBeenDecoded : 1;  // Decoded at least once?

  // Whether we're waiting to start animation. If we get a StartAnimation() call
  // but we don't yet have more than one frame, mPendingAnimation is set so that
  // we know to start animation later if/when we have more frames.
  bool mPendingAnimation : 1;

  // Whether the animation can stop, due to running out
  // of frames, or no more owning request
  bool mAnimationFinished : 1;

  // Whether, once we are done doing a metadata decode, we should immediately
  // kick off a full decode.
  bool mWantFullDecode : 1;

  TimeStamp mDrawStartTime;

  //////////////////////////////////////////////////////////////////////////////
  // Scaling.
  //////////////////////////////////////////////////////////////////////////////

  // Determines whether we can downscale during decode with the given
  // parameters.
  bool CanDownscaleDuringDecode(const nsIntSize& aSize, uint32_t aFlags);

  // Error handling.
  void DoError();

  class HandleErrorWorker : public Runnable {
   public:
    /**
     * Called from decoder threads when DoError() is called, since errors can't
     * be handled safely off-main-thread. Dispatches an event which reinvokes
     * DoError on the main thread if there isn't one already pending.
     */
    static void DispatchIfNeeded(RasterImage* aImage);

    NS_IMETHOD Run() override;

   private:
    explicit HandleErrorWorker(RasterImage* aImage);

    RefPtr<RasterImage> mImage;
  };

  // Helpers
  bool CanDiscard();

  bool IsOpaque();

  DrawableSurface RequestDecodeForSizeInternal(const gfx::IntSize& aSize,
                                               uint32_t aFlags);

 protected:
  explicit RasterImage(nsIURI* aURI = nullptr);

  bool ShouldAnimate() override;

  friend class ImageFactory;
};

inline NS_IMETHODIMP RasterImage::GetAnimationMode(uint16_t* aAnimationMode) {
  return GetAnimationModeInternal(aAnimationMode);
}

}  // namespace image
}  // namespace mozilla

/**
 * Casting RasterImage to nsISupports is ambiguous. This method handles that.
 */
inline nsISupports* ToSupports(mozilla::image::RasterImage* p) {
  return NS_ISUPPORTS_CAST(mozilla::image::ImageResource*, p);
}

#endif /* mozilla_image_RasterImage_h */