0d75524d1ee634f760791f08e4ca0ef488768848
[WebKit-https.git] / Source / WebCore / platform / graphics / cg / ImageSourceCG.cpp
1 /*
2  * Copyright (C) 2004, 2005, 2006, 2008 Apple Inc. All rights reserved.
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5  * modification, are permitted provided that the following conditions
6  * are met:
7  * 1. Redistributions of source code must retain the above copyright
8  *    notice, this list of conditions and the following disclaimer.
9  * 2. Redistributions in binary form must reproduce the above copyright
10  *    notice, this list of conditions and the following disclaimer in the
11  *    documentation and/or other materials provided with the distribution.
12  *
13  * THIS SOFTWARE IS PROVIDED BY APPLE INC. ``AS IS'' AND ANY
14  * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
15  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
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24  */
25
26 #include "config.h"
27 #include "ImageSource.h"
28
29 #if USE(CG)
30 #include "ImageSourceCG.h"
31
32 #include "ImageOrientation.h"
33 #include "IntPoint.h"
34 #include "IntSize.h"
35 #include "MIMETypeRegistry.h"
36 #include "SharedBuffer.h"
37 #if !PLATFORM(IOS)
38 #include <ApplicationServices/ApplicationServices.h>
39 #else
40 #include <CoreGraphics/CGImagePrivate.h>
41 #include <CoreGraphics/CoreGraphics.h>
42 #include <ImageIO/CGImageSourcePrivate.h>
43 #include <ImageIO/ImageIO.h>
44 #include <wtf/RetainPtr.h>
45 #endif
46
47 namespace WebCore {
48
49 const CFStringRef WebCoreCGImagePropertyAPNGUnclampedDelayTime = CFSTR("UnclampedDelayTime");
50 const CFStringRef WebCoreCGImagePropertyAPNGDelayTime = CFSTR("DelayTime");
51 const CFStringRef WebCoreCGImagePropertyAPNGLoopCount = CFSTR("LoopCount");
52
53 const CFStringRef kCGImageSourceShouldPreferRGB32 = CFSTR("kCGImageSourceShouldPreferRGB32");
54 const CFStringRef kCGImageSourceSkipMetadata = CFSTR("kCGImageSourceSkipMetadata");
55
56 #if !PLATFORM(COCOA)
57 size_t sharedBufferGetBytesAtPosition(void* info, void* buffer, off_t position, size_t count)
58 {
59     SharedBuffer* sharedBuffer = static_cast<SharedBuffer*>(info);
60     size_t sourceSize = sharedBuffer->size();
61     if (position >= sourceSize)
62         return 0;
63
64     const char* source = sharedBuffer->data() + position;
65     size_t amount = std::min<size_t>(count, sourceSize - position);
66     memcpy(buffer, source, amount);
67     return amount;
68 }
69
70 void sharedBufferRelease(void* info)
71 {
72     SharedBuffer* sharedBuffer = static_cast<SharedBuffer*>(info);
73     sharedBuffer->deref();
74 }
75 #endif
76
77 ImageSource::ImageSource(ImageSource::AlphaOption, ImageSource::GammaAndColorProfileOption)
78     : m_decoder(0)
79 #if PLATFORM(IOS)
80     , m_baseSubsampling(0)
81     , m_isProgressive(false)
82 #endif
83 {
84     // FIXME: AlphaOption and GammaAndColorProfileOption are ignored.
85 }
86
87 ImageSource::~ImageSource()
88 {
89     clear(true);
90 }
91
92 void ImageSource::clear(bool destroyAllFrames, size_t, SharedBuffer* data, bool allDataReceived)
93 {
94     // Recent versions of ImageIO discard previously decoded image frames if the client
95     // application no longer holds references to them, so there's no need to throw away
96     // the decoder unless we're explicitly asked to destroy all of the frames.
97     if (!destroyAllFrames)
98         return;
99
100     if (m_decoder) {
101         CFRelease(m_decoder);
102         m_decoder = 0;
103     }
104     if (data)
105         setData(data, allDataReceived);
106 }
107
108 #if !PLATFORM(IOS)
109 static CFDictionaryRef imageSourceOptions(ImageSource::ShouldSkipMetadata skipMetaData)
110 {
111     static CFDictionaryRef options;
112
113     if (!options) {
114         const unsigned numOptions = 3;
115         const CFBooleanRef imageSourceSkipMetadata = (skipMetaData == ImageSource::SkipMetadata) ? kCFBooleanTrue : kCFBooleanFalse;
116         const void* keys[numOptions] = { kCGImageSourceShouldCache, kCGImageSourceShouldPreferRGB32, kCGImageSourceSkipMetadata };
117         const void* values[numOptions] = { kCFBooleanTrue, kCFBooleanTrue, imageSourceSkipMetadata };
118         options = CFDictionaryCreate(NULL, keys, values, numOptions, 
119             &kCFTypeDictionaryKeyCallBacks, &kCFTypeDictionaryValueCallBacks);
120     }
121     return options;
122 }
123 #else
124 CFDictionaryRef ImageSource::imageSourceOptions(ShouldSkipMetadata skipMetaData, int requestedSubsampling) const
125 {
126     static CFDictionaryRef options[4] = {nullptr, nullptr, nullptr, nullptr};
127     int subsampling = std::min(3, m_isProgressive || requestedSubsampling < 0 ? 0 : (requestedSubsampling + m_baseSubsampling));
128
129     if (!options[subsampling]) {
130         int subsampleInt = 1 << subsampling; // [0..3] => [1, 2, 4, 8]
131         RetainPtr<CFNumberRef> subsampleNumber = adoptCF(CFNumberCreate(nullptr,  kCFNumberIntType,  &subsampleInt));
132         const CFIndex numOptions = 4;
133         const CFBooleanRef imageSourceSkipMetaData = (skipMetaData == ImageSource::SkipMetadata) ? kCFBooleanTrue : kCFBooleanFalse;
134         const void* keys[numOptions] = { kCGImageSourceShouldCache, kCGImageSourceShouldPreferRGB32, kCGImageSourceSubsampleFactor, kCGImageSourceSkipMetadata };
135         const void* values[numOptions] = { kCFBooleanTrue, kCFBooleanTrue, subsampleNumber.get(), imageSourceSkipMetaData };
136         options[subsampling] = CFDictionaryCreate(nullptr, keys, values, numOptions, &kCFTypeDictionaryKeyCallBacks, &kCFTypeDictionaryValueCallBacks);
137     }
138     return options[subsampling];
139 }
140 #endif
141
142 bool ImageSource::initialized() const
143 {
144     return m_decoder;
145 }
146
147 void ImageSource::setData(SharedBuffer* data, bool allDataReceived)
148 {
149 #if PLATFORM(COCOA)
150     if (!m_decoder)
151         m_decoder = CGImageSourceCreateIncremental(0);
152     // On Mac the NSData inside the SharedBuffer can be secretly appended to without the SharedBuffer's knowledge.  We use SharedBuffer's ability
153     // to wrap itself inside CFData to get around this, ensuring that ImageIO is really looking at the SharedBuffer.
154     CGImageSourceUpdateData(m_decoder, data->createCFData().get(), allDataReceived);
155 #else
156     if (!m_decoder) {
157         m_decoder = CGImageSourceCreateIncremental(0);
158     } else if (allDataReceived) {
159 #if !PLATFORM(WIN)
160         // 10.6 bug workaround: image sources with final=false fail to draw into PDF contexts, so re-create image source
161         // when data is complete. <rdar://problem/7874035> (<http://openradar.appspot.com/7874035>)
162         CFRelease(m_decoder);
163         m_decoder = CGImageSourceCreateIncremental(0);
164 #endif
165     }
166     // Create a CGDataProvider to wrap the SharedBuffer.
167     data->ref();
168     // We use the GetBytesAtPosition callback rather than the GetBytePointer one because SharedBuffer
169     // does not provide a way to lock down the byte pointer and guarantee that it won't move, which
170     // is a requirement for using the GetBytePointer callback.
171     CGDataProviderDirectCallbacks providerCallbacks = { 0, 0, 0, sharedBufferGetBytesAtPosition, sharedBufferRelease };
172     RetainPtr<CGDataProviderRef> dataProvider = adoptCF(CGDataProviderCreateDirect(data, data->size(), &providerCallbacks));
173     CGImageSourceUpdateDataProvider(m_decoder, dataProvider.get(), allDataReceived);
174 #endif
175 }
176
177 String ImageSource::filenameExtension() const
178 {
179     if (!m_decoder)
180         return String();
181     CFStringRef imageSourceType = CGImageSourceGetType(m_decoder);
182     return WebCore::preferredExtensionForImageSourceType(imageSourceType);
183 }
184
185 bool ImageSource::isSizeAvailable()
186 {
187     bool result = false;
188     CGImageSourceStatus imageSourceStatus = CGImageSourceGetStatus(m_decoder);
189
190     // Ragnaros yells: TOO SOON! You have awakened me TOO SOON, Executus!
191     if (imageSourceStatus >= kCGImageStatusIncomplete) {
192         RetainPtr<CFDictionaryRef> image0Properties = adoptCF(CGImageSourceCopyPropertiesAtIndex(m_decoder, 0, imageSourceOptions(SkipMetadata)));
193         if (image0Properties) {
194             CFNumberRef widthNumber = (CFNumberRef)CFDictionaryGetValue(image0Properties.get(), kCGImagePropertyPixelWidth);
195             CFNumberRef heightNumber = (CFNumberRef)CFDictionaryGetValue(image0Properties.get(), kCGImagePropertyPixelHeight);
196             result = widthNumber && heightNumber;
197         }
198     }
199     
200     return result;
201 }
202
203 static ImageOrientation orientationFromProperties(CFDictionaryRef imageProperties)
204 {
205     ASSERT(imageProperties);
206     CFNumberRef orientationProperty = (CFNumberRef)CFDictionaryGetValue(imageProperties, kCGImagePropertyOrientation);
207     if (!orientationProperty)
208         return DefaultImageOrientation;
209
210     int exifValue;
211     CFNumberGetValue(orientationProperty, kCFNumberIntType, &exifValue);
212     return ImageOrientation::fromEXIFValue(exifValue);
213 }
214
215 IntSize ImageSource::frameSizeAtIndex(size_t index, ImageOrientationDescription description) const
216 {
217     RetainPtr<CFDictionaryRef> properties = adoptCF(CGImageSourceCopyPropertiesAtIndex(m_decoder, index, imageSourceOptions(SkipMetadata)));
218
219     if (!properties)
220         return IntSize();
221
222     int w = 0, h = 0;
223     CFNumberRef num = (CFNumberRef)CFDictionaryGetValue(properties.get(), kCGImagePropertyPixelWidth);
224     if (num)
225         CFNumberGetValue(num, kCFNumberIntType, &w);
226     num = (CFNumberRef)CFDictionaryGetValue(properties.get(), kCGImagePropertyPixelHeight);
227     if (num)
228         CFNumberGetValue(num, kCFNumberIntType, &h);
229
230 #if PLATFORM(IOS)
231     if (!m_isProgressive) {
232         CFDictionaryRef jfifProperties = static_cast<CFDictionaryRef>(CFDictionaryGetValue(properties.get(), kCGImagePropertyJFIFDictionary));
233         if (jfifProperties) {
234             CFBooleanRef isProgCFBool = static_cast<CFBooleanRef>(CFDictionaryGetValue(jfifProperties, kCGImagePropertyJFIFIsProgressive));
235             if (isProgCFBool)
236                 m_isProgressive = CFBooleanGetValue(isProgCFBool);
237             // Workaround for <rdar://problem/5184655> - Hang rendering very large progressive JPEG. Decoding progressive
238             // images hangs for a very long time right now. Until this is fixed, don't sub-sample progressive images. This
239             // will cause them to fail our large image check and they won't be decoded.
240             // FIXME: Remove once underlying issue is fixed (<rdar://problem/5191418>)
241         }
242     }
243
244     if ((m_baseSubsampling == 0) && !m_isProgressive) {
245         IntSize subsampledSize(w, h);
246         const int cMaximumImageSizeBeforeSubsampling = 5 * 1024 * 1024;
247         while ((m_baseSubsampling < 3) && subsampledSize.width() * subsampledSize.height() > cMaximumImageSizeBeforeSubsampling) {
248             // We know the size, but the actual image is very large and should be sub-sampled.
249             // Increase the base subsampling and ask for the size again. If the image can be subsampled, the size will be
250             // greatly reduced. 4x sub-sampling will make us support up to 320MP (5MP * 4^3) images, which should be plenty.
251             // There's no callback from ImageIO when the size is available, so we do the check when we happen
252             // to check the size and its non - zero.
253             // Note: Some clients of this class don't call isSizeAvailable() so we can't rely on that.
254             ++m_baseSubsampling;
255             subsampledSize = frameSizeAtIndex(index, description.respectImageOrientation());
256         }
257         w = subsampledSize.width();
258         h = subsampledSize.height();
259     }
260 #endif
261
262     if ((description.respectImageOrientation() == RespectImageOrientation) && orientationFromProperties(properties.get()).usesWidthAsHeight())
263         return IntSize(h, w);
264
265     return IntSize(w, h);
266 }
267
268 ImageOrientation ImageSource::orientationAtIndex(size_t index) const
269 {
270     RetainPtr<CFDictionaryRef> properties = adoptCF(CGImageSourceCopyPropertiesAtIndex(m_decoder, index, imageSourceOptions(SkipMetadata)));
271     if (!properties)
272         return DefaultImageOrientation;
273
274     return orientationFromProperties(properties.get());
275 }
276
277 #if PLATFORM(IOS)
278 IntSize ImageSource::originalSize(RespectImageOrientationEnum shouldRespectOrientation) const
279 {
280     frameSizeAtIndex(0, shouldRespectOrientation);
281     RetainPtr<CFDictionaryRef> properties = adoptCF(CGImageSourceCopyPropertiesAtIndex(m_decoder, 0, imageSourceOptions(SkipMetadata, -1)));
282
283     if (!properties)
284         return IntSize();
285
286     int width = 0;
287     int height = 0;
288     CFNumberRef number = (CFNumberRef)CFDictionaryGetValue(properties.get(), kCGImagePropertyPixelWidth);
289     if (number)
290         CFNumberGetValue(number, kCFNumberIntType, &width);
291     number = static_cast<CFNumberRef>(CFDictionaryGetValue(properties.get(), kCGImagePropertyPixelHeight));
292     if (number)
293         CFNumberGetValue(number, kCFNumberIntType, &height);
294
295     if ((shouldRespectOrientation == RespectImageOrientation) && orientationFromProperties(properties.get()).usesWidthAsHeight())
296         return IntSize(height, width);
297
298     return IntSize(width, height);
299 }
300 #endif
301
302 IntSize ImageSource::size(ImageOrientationDescription description) const
303 {
304     return frameSizeAtIndex(0, description);
305 }
306
307 bool ImageSource::getHotSpot(IntPoint& hotSpot) const
308 {
309     RetainPtr<CFDictionaryRef> properties = adoptCF(CGImageSourceCopyPropertiesAtIndex(m_decoder, 0, imageSourceOptions(SkipMetadata)));
310     if (!properties)
311         return false;
312
313     int x = -1, y = -1;
314     CFNumberRef num = (CFNumberRef)CFDictionaryGetValue(properties.get(), CFSTR("hotspotX"));
315     if (!num || !CFNumberGetValue(num, kCFNumberIntType, &x))
316         return false;
317
318     num = (CFNumberRef)CFDictionaryGetValue(properties.get(), CFSTR("hotspotY"));
319     if (!num || !CFNumberGetValue(num, kCFNumberIntType, &y))
320         return false;
321
322     if (x < 0 || y < 0)
323         return false;
324
325     hotSpot = IntPoint(x, y);
326     return true;
327 }
328
329 size_t ImageSource::bytesDecodedToDetermineProperties() const
330 {
331     // Measured by tracing malloc/calloc calls on Mac OS 10.6.6, x86_64.
332     // A non-zero value ensures cached images with no decoded frames still enter
333     // the live decoded resources list when the CGImageSource decodes image
334     // properties, allowing the cache to prune the partially decoded image.
335     // This value is likely to be inaccurate on other platforms, but the overall
336     // behavior is unchanged.
337     return 13088;
338 }
339     
340 int ImageSource::repetitionCount()
341 {
342     if (!initialized())
343         return cAnimationLoopOnce;
344
345     RetainPtr<CFDictionaryRef> properties = adoptCF(CGImageSourceCopyProperties(m_decoder, imageSourceOptions(SkipMetadata)));
346     if (!properties)
347         return cAnimationLoopOnce;
348
349     CFDictionaryRef gifProperties = (CFDictionaryRef)CFDictionaryGetValue(properties.get(), kCGImagePropertyGIFDictionary);
350     if (gifProperties) {
351         CFNumberRef num = (CFNumberRef)CFDictionaryGetValue(gifProperties, kCGImagePropertyGIFLoopCount);
352
353         // No property means loop once.
354         if (!num)
355             return cAnimationLoopOnce;
356
357         int loopCount;
358         CFNumberGetValue(num, kCFNumberIntType, &loopCount);
359
360         // A property with value 0 means loop forever.
361         return loopCount ? loopCount : cAnimationLoopInfinite;
362     }
363
364     CFDictionaryRef pngProperties = (CFDictionaryRef)CFDictionaryGetValue(properties.get(), kCGImagePropertyPNGDictionary);
365     if (pngProperties) {
366         CFNumberRef num = (CFNumberRef)CFDictionaryGetValue(pngProperties, WebCoreCGImagePropertyAPNGLoopCount);
367         if (!num)
368             return cAnimationLoopOnce;
369
370         int loopCount;
371         CFNumberGetValue(num, kCFNumberIntType, &loopCount);
372         return loopCount ? loopCount : cAnimationLoopInfinite;
373     }
374
375     // Turns out we're not an animated image after all, so we don't animate.
376     return cAnimationNone;
377 }
378
379 size_t ImageSource::frameCount() const
380 {
381     return m_decoder ? CGImageSourceGetCount(m_decoder) : 0;
382 }
383
384 CGImageRef ImageSource::createFrameAtIndex(size_t index, float* scale)
385 {
386     UNUSED_PARAM(scale);
387
388     if (!initialized())
389         return 0;
390
391 #if !PLATFORM(IOS)
392     UNUSED_PARAM(scale);
393     RetainPtr<CGImageRef> image = adoptCF(CGImageSourceCreateImageAtIndex(m_decoder, index, imageSourceOptions(SkipMetadata)));
394 #else
395     // Subsampling can be 1, 2 or 3, which means quarter-, sixteenth- and sixty-fourth-size, respectively.
396     // A zero or negative value means no subsampling.
397     int subsampling = scale ? static_cast<int>(log2f(1.0f / std::max(0.1f, std::min(1.0f, *scale)))) : -1;
398     RetainPtr<CGImageRef> image = adoptCF(CGImageSourceCreateImageAtIndex(m_decoder, index, imageSourceOptions(SkipMetadata, subsampling)));
399
400     // <rdar://problem/7371198> - CoreGraphics changed the default caching behaviour in iOS 4.0 to kCGImageCachingTransient
401     // which caused a performance regression for us since the images had to be resampled/recreated every time we called
402     // CGContextDrawImage. We now tell CG to cache the drawn images. See also <rdar://problem/14366755> -
403     // CoreGraphics needs to un-deprecate kCGImageCachingTemporary since it's still not the default.
404 #if COMPILER(CLANG)
405 #pragma clang diagnostic push
406 #pragma clang diagnostic ignored "-Wdeprecated-declarations"
407 #endif
408     CGImageSetCachingFlags(image.get(), kCGImageCachingTemporary);
409 #if COMPILER(CLANG)
410 #pragma clang diagnostic pop
411 #endif
412     if (scale) {
413         if (subsampling > 0)
414             *scale = static_cast<float>(CGImageGetWidth(image.get())) / size(DoNotRespectImageOrientation).width();
415         else {
416             ASSERT(static_cast<int>(CGImageGetWidth(image.get())) == size(DoNotRespectImageOrientation).width());
417             *scale = 1;
418         }
419     }
420 #endif // !PLATFORM(IOS)
421     CFStringRef imageUTI = CGImageSourceGetType(m_decoder);
422     static const CFStringRef xbmUTI = CFSTR("public.xbitmap-image");
423     if (!imageUTI || !CFEqual(imageUTI, xbmUTI))
424         return image.leakRef();
425     
426     // If it is an xbm image, mask out all the white areas to render them transparent.
427     const CGFloat maskingColors[6] = {255, 255,  255, 255, 255, 255};
428     RetainPtr<CGImageRef> maskedImage = adoptCF(CGImageCreateWithMaskingColors(image.get(), maskingColors));
429     if (!maskedImage)
430         return image.leakRef();
431
432     return maskedImage.leakRef();
433 }
434
435 bool ImageSource::frameIsCompleteAtIndex(size_t index)
436 {
437     ASSERT(frameCount());
438
439     // CGImageSourceGetStatusAtIndex claims that all frames of a multi-frame image are incomplete
440     // when we've not yet received the complete data for an image that is using an incremental data
441     // source (<rdar://problem/7679174>). We work around this by special-casing all frames except the
442     // last in an image and treating them as complete if they are present and reported as being
443     // incomplete. We do this on the assumption that loading new data can only modify the existing last
444     // frame or append new frames. The last frame is only treated as being complete if the image source
445     // reports it as such. This ensures that it is truly the last frame of the image rather than just
446     // the last that we currently have data for.
447
448     CGImageSourceStatus frameStatus = CGImageSourceGetStatusAtIndex(m_decoder, index);
449     if (index < frameCount() - 1)
450         return frameStatus >= kCGImageStatusIncomplete;
451
452     return frameStatus == kCGImageStatusComplete;
453 }
454
455 float ImageSource::frameDurationAtIndex(size_t index)
456 {
457     if (!initialized())
458         return 0;
459
460     float duration = 0;
461     RetainPtr<CFDictionaryRef> properties = adoptCF(CGImageSourceCopyPropertiesAtIndex(m_decoder, index, imageSourceOptions(SkipMetadata)));
462     if (properties) {
463         CFDictionaryRef gifProperties = (CFDictionaryRef)CFDictionaryGetValue(properties.get(), kCGImagePropertyGIFDictionary);
464         if (gifProperties) {
465             if (CFNumberRef num = (CFNumberRef)CFDictionaryGetValue(gifProperties, kCGImagePropertyGIFUnclampedDelayTime)) {
466                 // Use the unclamped frame delay if it exists.
467                 CFNumberGetValue(num, kCFNumberFloatType, &duration);
468             } else if (CFNumberRef num = (CFNumberRef)CFDictionaryGetValue(gifProperties, kCGImagePropertyGIFDelayTime)) {
469                 // Fall back to the clamped frame delay if the unclamped frame delay does not exist.
470                 CFNumberGetValue(num, kCFNumberFloatType, &duration);
471             }
472         }
473
474         CFDictionaryRef pngProperties = (CFDictionaryRef)CFDictionaryGetValue(properties.get(), kCGImagePropertyPNGDictionary);
475         if (pngProperties) {
476             if (CFNumberRef num = (CFNumberRef)CFDictionaryGetValue(pngProperties, WebCoreCGImagePropertyAPNGUnclampedDelayTime))
477                 CFNumberGetValue(num, kCFNumberFloatType, &duration);
478             else if (CFNumberRef num = (CFNumberRef)CFDictionaryGetValue(pngProperties, WebCoreCGImagePropertyAPNGDelayTime))
479                 CFNumberGetValue(num, kCFNumberFloatType, &duration);
480         }
481     }
482
483     // Many annoying ads specify a 0 duration to make an image flash as quickly as possible.
484     // We follow Firefox's behavior and use a duration of 100 ms for any frames that specify
485     // a duration of <= 10 ms. See <rdar://problem/7689300> and <http://webkit.org/b/36082>
486     // for more information.
487     if (duration < 0.011f)
488         return 0.100f;
489     return duration;
490 }
491
492 bool ImageSource::frameHasAlphaAtIndex(size_t index)
493 {
494     if (!m_decoder)
495         return false; // FIXME: why doesn't this return true?
496
497     if (!frameIsCompleteAtIndex(index))
498         return true;
499
500     CFStringRef imageType = CGImageSourceGetType(m_decoder);
501
502     // Return false if there is no image type or the image type is JPEG, because
503     // JPEG does not support alpha transparency.
504     if (!imageType || CFEqual(imageType, CFSTR("public.jpeg")))
505         return false;
506
507     // FIXME: Could return false for other non-transparent image formats.
508     // FIXME: Could maybe return false for a GIF Frame if we have enough info in the GIF properties dictionary
509     // to determine whether or not a transparent color was defined.
510     return true;
511 }
512
513 unsigned ImageSource::frameBytesAtIndex(size_t index) const
514 {
515     IntSize frameSize = frameSizeAtIndex(index, ImageOrientationDescription(RespectImageOrientation));
516     return frameSize.width() * frameSize.height() * 4;
517 }
518
519 }
520
521 #endif // USE(CG)