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Side by Side Diff: src/images/SkImageDecoder_libwebp.cpp

Issue 12604006: Upstream Android modifications to the image encoders/decoders. (Closed) Base URL: https://skia.googlecode.com/svn/trunk
Patch Set: addressing robert's comments Created 7 years, 9 months ago
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1 /*
2 * Copyright 2010, The Android Open Source Project
3 *
4 * Licensed under the Apache License, Version 2.0 (the "License");
5 * you may not use this file except in compliance with the License.
6 * You may obtain a copy of the License at
7 *
8 * http://www.apache.org/licenses/LICENSE-2.0
9 *
10 * Unless required by applicable law or agreed to in writing, software
11 * distributed under the License is distributed on an "AS IS" BASIS,
12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13 * See the License for the specific language governing permissions and
14 * limitations under the License.
15 */
16
17 #include "SkImageDecoder.h"
18 #include "SkImageEncoder.h"
19 #include "SkColorPriv.h"
20 #include "SkScaledBitmapSampler.h"
21 #include "SkStream.h"
22 #include "SkTemplates.h"
23 #include "SkUtils.h"
24 #include "SkTScopedPtr.h"
25
26 // A WebP decoder only, on top of (subset of) libwebp
27 // For more information on WebP image format, and libwebp library, see:
28 // http://code.google.com/speed/webp/
29 // http://www.webmproject.org/code/#libwebp_webp_image_decoder_library
30 // http://review.webmproject.org/gitweb?p=libwebp.git
31
32 #include <stdio.h>
33 extern "C" {
34 // If moving libwebp out of skia source tree, path for webp headers must be
35 // updated accordingly. Here, we enforce using local copy in webp sub-directory.
36 #include "webp/decode.h"
37 #include "webp/encode.h"
38 }
39
40 #ifdef ANDROID
41 #include <cutils/properties.h>
42
43 // Key to lookup the size of memory buffer set in system property
44 static const char KEY_MEM_CAP[] = "ro.media.dec.webp.memcap";
45 #endif
46
47 // this enables timing code to report milliseconds for a decode
48 //#define TIME_DECODE
49
50 //////////////////////////////////////////////////////////////////////////
51 //////////////////////////////////////////////////////////////////////////
52
53 // Define VP8 I/O on top of Skia stream
54
55 //////////////////////////////////////////////////////////////////////////
56 //////////////////////////////////////////////////////////////////////////
57
58 static const size_t WEBP_VP8_HEADER_SIZE = 64;
59 static const size_t WEBP_IDECODE_BUFFER_SZ = (1 << 16);
60
61 // Parse headers of RIFF container, and check for valid Webp (VP8) content.
robertphillips 2013/03/11 20:10:16 // Return false if file ...
62 static bool webp_parse_header(SkStream* stream, int* width, int* height,
robertphillips 2013/03/11 20:10:16 move to prior line?
djsollen 2013/03/12 15:52:32 Done.
63 int* alpha) {
64 unsigned char buffer[WEBP_VP8_HEADER_SIZE];
65 const uint32_t contentSize = stream->getLength();
66 const size_t len = stream->read(buffer, WEBP_VP8_HEADER_SIZE);
67 const uint32_t read_bytes = (contentSize < WEBP_VP8_HEADER_SIZE) ?
robertphillips 2013/03/11 20:10:16 tab the next line over?
djsollen 2013/03/12 15:52:32 Done.
68 contentSize : WEBP_VP8_HEADER_SIZE;
69 if (len != read_bytes) {
70 return false; // can't read enough
71 }
72
73 WebPBitstreamFeatures features;
74 VP8StatusCode status = WebPGetFeatures(buffer, read_bytes, &features);
robertphillips 2013/03/11 20:10:16 reverse order to have constant on lhs?
djsollen 2013/03/12 15:52:32 Done.
75 if (status != VP8_STATUS_OK) {
76 return false; // Invalid WebP file.
77 }
78 *width = features.width;
79 *height = features.height;
80 *alpha = features.has_alpha;
81
82 // sanity check for image size that's about to be decoded.
83 {
84 Sk64 size;
85 size.setMul(*width, *height);
86 if (size.isNeg() || !size.is32()) {
87 return false;
88 }
89 // now check that if we are 4-bytes per pixel, we also don't overflow
90 if (size.get32() > (0x7FFFFFFF >> 2)) {
91 return false;
92 }
93 }
94 return true;
95 }
96
97 class SkWEBPImageDecoder: public SkImageDecoder {
98 public:
robertphillips 2013/03/11 20:10:16 override?
djsollen 2013/03/12 15:52:32 Done.
99 virtual Format getFormat() const {
100 return kWEBP_Format;
101 }
102
robertphillips 2013/03/11 20:10:16 ctor to init inputStream?
djsollen 2013/03/12 15:52:32 Done.
103 protected:
104 virtual bool onBuildTileIndex(SkStream *stream, int *width, int *height) SK_ OVERRIDE;
105 virtual bool onDecodeRegion(SkBitmap* bitmap, const SkIRect& rect) SK_OVERRI DE;
106 virtual bool onDecode(SkStream* stream, SkBitmap* bm, Mode) SK_OVERRIDE;
107
108 private:
109 bool setDecodeConfig(SkBitmap* decodedBitmap, int width, int height);
robertphillips 2013/03/11 20:10:16 f prefix on all variables?
djsollen 2013/03/12 15:52:32 Done.
110 SkStream *inputStream;
111 int origWidth;
112 int origHeight;
113 int hasAlpha;
robertphillips 2013/03/11 20:10:16 inherited?
114 };
115
116 //////////////////////////////////////////////////////////////////////////
117
robertphillips 2013/03/11 20:10:16 wrap this guy in "#ifdef TIME_DECODE"?
djsollen 2013/03/12 15:52:32 Done.
118 #include "SkTime.h"
119
robertphillips 2013/03/11 20:10:16 Do we not have this guy somewhere else? It seems l
120 class AutoTimeMillis {
121 public:
122 AutoTimeMillis(const char label[]) :
123 fLabel(label) {
robertphillips 2013/03/11 20:10:16 NULL ==
djsollen 2013/03/12 15:52:32 Done.
124 if (!fLabel) {
125 fLabel = "";
126 }
127 fNow = SkTime::GetMSecs();
128 }
129 ~AutoTimeMillis() {
130 SkDebugf("---- Time (ms): %s %d\n", fLabel, SkTime::GetMSecs() - fNow);
131 }
132 private:
133 const char* fLabel;
134 SkMSec fNow;
135 };
136
137 ///////////////////////////////////////////////////////////////////////////////
138
139 // This guy exists just to aid in debugging, as it allows debuggers to just
140 // set a break-point in one place to see all error exists.
141 static bool return_false(const SkBitmap& bm, const char msg[]) {
142 #if SK_DEBUG
143 SkDebugf("libwebp error %s [%d %d]", msg, bm.width(), bm.height());
144 #endif
145 return false; // must always return false
146 }
147
148 static WEBP_CSP_MODE webp_decode_mode(SkBitmap* decodedBitmap, int hasAlpha) {
149 WEBP_CSP_MODE mode = MODE_LAST;
150 SkBitmap::Config config = decodedBitmap->config();
151 // For images that have alpha, choose appropriate color mode (MODE_rgbA,
152 // MODE_rgbA_4444) that pre-multiplies RGB pixel values with transparency
153 // factor (alpha).
154 if (config == SkBitmap::kARGB_8888_Config) {
155 mode = hasAlpha ? MODE_rgbA : MODE_RGBA;
156 } else if (config == SkBitmap::kARGB_4444_Config) {
157 mode = hasAlpha ? MODE_rgbA_4444 : MODE_RGBA_4444;
158 } else if (config == SkBitmap::kRGB_565_Config) {
159 mode = MODE_RGB_565;
160 }
161 SkASSERT(mode != MODE_LAST);
162 return mode;
163 }
164
165 // Incremental WebP image decoding. Reads input buffer of 64K size iteratively
166 // and decodes this block to appropriate color-space as per config object.
robertphillips 2013/03/11 20:10:16 _const_ WebPDecoderConfig? It actually looks like
167 static bool webp_idecode(SkStream* stream, WebPDecoderConfig& config) {
168 WebPIDecoder* idec = WebPIDecode(NULL, 0, &config);
robertphillips 2013/03/11 20:10:16 NULL on lhs
djsollen 2013/03/12 15:52:32 Done.
169 if (idec == NULL) {
170 WebPFreeDecBuffer(&config.output);
171 return false;
172 }
173
174 stream->rewind();
175 const uint32_t contentSize = stream->getLength();
176 const uint32_t read_buffer_size = (contentSize < WEBP_IDECODE_BUFFER_SZ) ?
robertphillips 2013/03/11 20:10:16 indent?
djsollen 2013/03/12 15:52:32 Done.
177 contentSize : WEBP_IDECODE_BUFFER_SZ;
178 SkAutoMalloc srcStorage(read_buffer_size);
179 unsigned char* input = (uint8_t*)srcStorage.get();
robertphillips 2013/03/11 20:10:16 NULL on left?
djsollen 2013/03/12 15:52:32 Done.
180 if (input == NULL) {
181 WebPIDelete(idec);
182 WebPFreeDecBuffer(&config.output);
183 return false;
184 }
185
robertphillips 2013/03/11 20:10:16 bytesRemaining
djsollen 2013/03/12 15:52:32 Done.
186 uint32_t bytes_remaining = contentSize;
187 while (bytes_remaining > 0) {
robertphillips 2013/03/11 20:10:16 bytesToRead
188 const uint32_t bytes_to_read =
189 (bytes_remaining < WEBP_IDECODE_BUFFER_SZ) ?
190 bytes_remaining : WEBP_IDECODE_BUFFER_SZ;
191
robertphillips 2013/03/11 20:10:16 bytesRead
192 const size_t bytes_read = stream->read(input, bytes_to_read);
robertphillips 2013/03/11 20:10:16 0 on LHS
193 if (bytes_read == 0) {
194 break;
195 }
196
197 VP8StatusCode status = WebPIAppend(idec, input, bytes_read);
robertphillips 2013/03/11 20:10:16 constants on LHS
djsollen 2013/03/12 15:52:32 Done.
198 if (status == VP8_STATUS_OK || status == VP8_STATUS_SUSPENDED) {
199 bytes_remaining -= bytes_read;
200 } else {
201 break;
202 }
203 }
204 srcStorage.free();
205 WebPIDelete(idec);
206 WebPFreeDecBuffer(&config.output);
207
208 if (bytes_remaining > 0) {
209 return false;
210 } else {
211 return true;
212 }
213 }
214
215 static bool webp_get_config_resize(WebPDecoderConfig& config,
216 SkBitmap* decodedBitmap,
217 int width, int height, int hasAlpha) {
218 WEBP_CSP_MODE mode = webp_decode_mode(decodedBitmap, hasAlpha);
robertphillips 2013/03/11 20:10:16 constant on LHS
djsollen 2013/03/12 15:52:32 Done.
219 if (mode == MODE_LAST) {
220 return false;
221 }
222
223 if (WebPInitDecoderConfig(&config) == 0) {
224 return false;
225 }
226
227 config.output.colorspace = mode;
228 config.output.u.RGBA.rgba = (uint8_t*)decodedBitmap->getPixels();
229 config.output.u.RGBA.stride = decodedBitmap->rowBytes();
230 config.output.u.RGBA.size = decodedBitmap->getSize();
231 config.output.is_external_memory = 1;
232
233 if (width != decodedBitmap->width() ||
robertphillips 2013/03/11 20:10:16 move to prior line
djsollen 2013/03/12 15:52:32 Done.
234 height != decodedBitmap->height()) {
235 config.options.use_scaling = 1;
236 config.options.scaled_width = decodedBitmap->width();
237 config.options.scaled_height = decodedBitmap->height();
238 }
239
240 return true;
241 }
242
243 static bool webp_get_config_resize_crop(WebPDecoderConfig& config,
244 SkBitmap* decodedBitmap,
245 SkIRect region, int hasAlpha) {
246
247 if (!webp_get_config_resize(
robertphillips 2013/03/11 20:10:16 indentation
djsollen 2013/03/12 15:52:32 Done.
248 config, decodedBitmap, region.width(), region.height(), hasAlpha)) {
249 return false;
250 }
251
252 config.options.use_cropping = 1;
253 config.options.crop_left = region.fLeft;
254 config.options.crop_top = region.fTop;
255 config.options.crop_width = region.width();
256 config.options.crop_height = region.height();
257
258 return true;
259 }
260
261 bool SkWEBPImageDecoder::setDecodeConfig(SkBitmap* decodedBitmap,
262 int width, int height) {
263 SkBitmap::Config config = this->getPrefConfig(k32Bit_SrcDepth, hasAlpha);
264
265 // YUV converter supports output in RGB565, RGBA4444 and RGBA8888 formats.
266 if (hasAlpha) {
267 if (config != SkBitmap::kARGB_4444_Config) {
268 config = SkBitmap::kARGB_8888_Config;
269 }
270 } else {
271 if (config != SkBitmap::kRGB_565_Config &&
272 config != SkBitmap::kARGB_4444_Config) {
273 config = SkBitmap::kARGB_8888_Config;
274 }
275 }
276
277 if (!this->chooseFromOneChoice(config, width, height)) {
278 return false;
279 }
280
281 decodedBitmap->setConfig(config, width, height, 0);
282
283 decodedBitmap->setIsOpaque(!hasAlpha);
284
285 return true;
286 }
287
288 bool SkWEBPImageDecoder::onBuildTileIndex(SkStream* stream,
289 int *width, int *height) {
290 int origWidth, origHeight, hasAlpha;
291 if (!webp_parse_header(stream, &origWidth, &origHeight, &hasAlpha)) {
292 return false;
293 }
294
295 stream->rewind();
296 *width = origWidth;
297 *height = origHeight;
298
299 this->inputStream = stream;
300 this->origWidth = origWidth;
301 this->origHeight = origHeight;
302 this->hasAlpha = hasAlpha;
303
304 return true;
305 }
306
robertphillips 2013/03/11 20:10:16 is_config_compatible
djsollen 2013/03/12 15:52:32 Done.
307 static bool isConfigCompatible(SkBitmap* bitmap) {
308 SkBitmap::Config config = bitmap->config();
309 return config == SkBitmap::kARGB_4444_Config ||
310 config == SkBitmap::kRGB_565_Config ||
311 config == SkBitmap::kARGB_8888_Config;
312 }
313
314 bool SkWEBPImageDecoder::onDecodeRegion(SkBitmap* decodedBitmap,
315 const SkIRect& region) {
316 SkIRect rect = SkIRect::MakeWH(origWidth, origHeight);
317
318 if (!rect.intersect(region)) {
319 // If the requested region is entirely outsides the image, just
320 // returns false
321 return false;
322 }
323
324 const int sampleSize = this->getSampleSize();
325 SkScaledBitmapSampler sampler(rect.width(), rect.height(), sampleSize);
326 const int width = sampler.scaledWidth();
327 const int height = sampler.scaledHeight();
328
329 // The image can be decoded directly to decodedBitmap if
330 // 1. the region is within the image range
331 // 2. bitmap's config is compatible
332 // 3. bitmap's size is same as the required region (after sampled)
333 bool directDecode = (rect == region) &&
334 (decodedBitmap->isNull() ||
335 (isConfigCompatible(decodedBitmap) &&
336 (decodedBitmap->width() == width) &&
337 (decodedBitmap->height() == height)));
338 SkTScopedPtr<SkBitmap> adb;
339 SkBitmap *bitmap = decodedBitmap;
340
341 if (!directDecode) {
342 // allocates a temp bitmap
343 bitmap = new SkBitmap;
344 adb.reset(bitmap);
345 }
346
347 if (bitmap->isNull()) {
348 if (!setDecodeConfig(bitmap, width, height)) {
349 return false;
350 }
351 // alloc from native heap if it is a temp bitmap. (prevent GC)
352 bool allocResult = (bitmap == decodedBitmap)
353 ? allocPixelRef(bitmap, NULL)
354 : bitmap->allocPixels();
355 if (!allocResult) {
356 return return_false(*decodedBitmap, "allocPixelRef");
357 }
358 } else {
359 // This is also called in setDecodeConfig in above block.
360 // i.e., when bitmap->isNull() is true.
361 if (!chooseFromOneChoice(bitmap->config(), width, height)) {
362 return false;
363 }
364 }
365
366 SkAutoLockPixels alp(*bitmap);
367 WebPDecoderConfig config;
368 if (!webp_get_config_resize_crop(config, bitmap, rect, hasAlpha)) {
369 return false;
370 }
371
372 // Decode the WebP image data stream using WebP incremental decoding for
373 // the specified cropped image-region.
374 if (!webp_idecode(this->inputStream, config)) {
375 return false;
376 }
377
378 if (!directDecode) {
379 cropBitmap(decodedBitmap, bitmap, sampleSize, region.x(), region.y(),
robertphillips 2013/03/11 20:10:16 add 1 space
djsollen 2013/03/12 15:52:32 Done.
380 region.width(), region.height(), rect.x(), rect.y());
381 }
382 return true;
383 }
384
385 bool SkWEBPImageDecoder::onDecode(SkStream* stream, SkBitmap* decodedBitmap,
386 Mode mode) {
387 #ifdef TIME_DECODE
388 AutoTimeMillis atm("WEBP Decode");
389 #endif
390
391 int origWidth, origHeight, hasAlpha;
392 if (!webp_parse_header(stream, &origWidth, &origHeight, &hasAlpha)) {
393 return false;
394 }
395 this->hasAlpha = hasAlpha;
396
397 const int sampleSize = this->getSampleSize();
398 SkScaledBitmapSampler sampler(origWidth, origHeight, sampleSize);
399
400 // If only bounds are requested, done
401 if (SkImageDecoder::kDecodeBounds_Mode == mode) {
402 if (!setDecodeConfig(decodedBitmap, sampler.scaledWidth(),
403 sampler.scaledHeight())) {
404 return false;
405 }
406 return true;
407 }
408
409 // No Bitmap reuse supported for this format
410 if (!decodedBitmap->isNull()) {
411 return false;
412 }
413 if (!setDecodeConfig(decodedBitmap, sampler.scaledWidth(),
414 sampler.scaledHeight())) {
415 return false;
416 }
417
418 if (!this->allocPixelRef(decodedBitmap, NULL)) {
419 return return_false(*decodedBitmap, "allocPixelRef");
420 }
421
422 SkAutoLockPixels alp(*decodedBitmap);
423
424 WebPDecoderConfig config;
425 if (!webp_get_config_resize(config, decodedBitmap, origWidth, origHeight,
426 hasAlpha)) {
427 return false;
428 }
429
430 // Decode the WebP image data stream using WebP incremental decoding.
431 return webp_idecode(stream, config);
432 }
433
434 ///////////////////////////////////////////////////////////////////////////////
435
436 typedef void (*ScanlineImporter)(const uint8_t* in, uint8_t* out, int width,
437 const SkPMColor* SK_RESTRICT ctable);
438
439 static void ARGB_8888_To_RGB(const uint8_t* in, uint8_t* rgb, int width,
440 const SkPMColor*) {
441 const uint32_t* SK_RESTRICT src = (const uint32_t*)in;
442 for (int i = 0; i < width; ++i) {
443 const uint32_t c = *src++;
444 rgb[0] = SkGetPackedR32(c);
445 rgb[1] = SkGetPackedG32(c);
446 rgb[2] = SkGetPackedB32(c);
447 rgb += 3;
448 }
449 }
450
451 static void RGB_565_To_RGB(const uint8_t* in, uint8_t* rgb, int width,
452 const SkPMColor*) {
453 const uint16_t* SK_RESTRICT src = (const uint16_t*)in;
454 for (int i = 0; i < width; ++i) {
455 const uint16_t c = *src++;
456 rgb[0] = SkPacked16ToR32(c);
457 rgb[1] = SkPacked16ToG32(c);
458 rgb[2] = SkPacked16ToB32(c);
459 rgb += 3;
460 }
461 }
462
463 static void ARGB_4444_To_RGB(const uint8_t* in, uint8_t* rgb, int width,
464 const SkPMColor*) {
465 const SkPMColor16* SK_RESTRICT src = (const SkPMColor16*)in;
466 for (int i = 0; i < width; ++i) {
467 const SkPMColor16 c = *src++;
468 rgb[0] = SkPacked4444ToR32(c);
469 rgb[1] = SkPacked4444ToG32(c);
470 rgb[2] = SkPacked4444ToB32(c);
471 rgb += 3;
472 }
473 }
474
475 static void Index8_To_RGB(const uint8_t* in, uint8_t* rgb, int width,
476 const SkPMColor* SK_RESTRICT ctable) {
477 const uint8_t* SK_RESTRICT src = (const uint8_t*)in;
478 for (int i = 0; i < width; ++i) {
479 const uint32_t c = ctable[*src++];
480 rgb[0] = SkGetPackedR32(c);
481 rgb[1] = SkGetPackedG32(c);
482 rgb[2] = SkGetPackedB32(c);
483 rgb += 3;
484 }
485 }
486
487 static ScanlineImporter ChooseImporter(const SkBitmap::Config& config) {
488 switch (config) {
489 case SkBitmap::kARGB_8888_Config:
490 return ARGB_8888_To_RGB;
491 case SkBitmap::kRGB_565_Config:
492 return RGB_565_To_RGB;
493 case SkBitmap::kARGB_4444_Config:
494 return ARGB_4444_To_RGB;
495 case SkBitmap::kIndex8_Config:
496 return Index8_To_RGB;
497 default:
498 return NULL;
499 }
500 }
501
robertphillips 2013/03/11 20:10:16 should this return a bool?
502 static int StreamWriter(const uint8_t* data, size_t data_size,
503 const WebPPicture* const picture) {
504 SkWStream* const stream = (SkWStream*)picture->custom_ptr;
505 return stream->write(data, data_size) ? 1 : 0;
506 }
507
508 class SkWEBPImageEncoder : public SkImageEncoder {
509 protected:
robertphillips 2013/03/11 20:10:16 override
510 virtual bool onEncode(SkWStream* stream, const SkBitmap& bm, int quality);
robertphillips 2013/03/11 20:10:16 private: inherited
511 };
512
513 bool SkWEBPImageEncoder::onEncode(SkWStream* stream, const SkBitmap& bm,
514 int quality) {
515 const SkBitmap::Config config = bm.getConfig();
516 const ScanlineImporter scanline_import = ChooseImporter(config);
517 if (NULL == scanline_import) {
518 return false;
519 }
520
521 SkAutoLockPixels alp(bm);
522 SkAutoLockColors ctLocker;
523 if (NULL == bm.getPixels()) {
524 return false;
525 }
526
527 WebPConfig webp_config;
528 if (!WebPConfigPreset(&webp_config, WEBP_PRESET_DEFAULT, quality)) {
529 return false;
530 }
531
532 WebPPicture pic;
533 WebPPictureInit(&pic);
534 pic.width = bm.width();
535 pic.height = bm.height();
536 pic.writer = StreamWriter;
537 pic.custom_ptr = (void*)stream;
538
539 const SkPMColor* colors = ctLocker.lockColors(bm);
540 const uint8_t* src = (uint8_t*)bm.getPixels();
robertphillips 2013/03/11 20:10:16 rgbStride
541 const int rgb_stride = pic.width * 3;
542
543 // Import (for each scanline) the bit-map image (in appropriate color-space)
544 // to RGB color space.
robertphillips 2013/03/11 20:10:16 SkNew
545 uint8_t* rgb = new uint8_t[rgb_stride * pic.height];
546 for (int y = 0; y < pic.height; ++y) {
547 scanline_import(src + y * bm.rowBytes(), rgb + y * rgb_stride,
548 pic.width, colors);
549 }
550
551 bool ok = WebPPictureImportRGB(&pic, rgb, rgb_stride);
552 delete[] rgb;
553
554 ok = ok && WebPEncode(&webp_config, &pic);
555 WebPPictureFree(&pic);
556
557 return ok;
558 }
559
560
561 ///////////////////////////////////////////////////////////////////////////////
562 DEFINE_DECODER_CREATOR(WEBPImageDecoder);
563 DEFINE_ENCODER_CREATOR(WEBPImageEncoder);
564 ///////////////////////////////////////////////////////////////////////////////
565
566 #include "SkTRegistry.h"
567
568 static SkImageDecoder* sk_libwebp_dfactory(SkStream* stream) {
569 int width, height, hasAlpha;
570 if (!webp_parse_header(stream, &width, &height, &hasAlpha)) {
571 return NULL;
572 }
573
574 // Magic matches, call decoder
575 return SkNEW(SkWEBPImageDecoder);
576 }
577
578 static SkImageEncoder* sk_libwebp_efactory(SkImageEncoder::Type t) {
579 return (SkImageEncoder::kWEBP_Type == t) ? SkNEW(SkWEBPImageEncoder) : NUL L;
580 }
581
582 static SkTRegistry<SkImageDecoder*, SkStream*> gDReg(sk_libwebp_dfactory);
583 static SkTRegistry<SkImageEncoder*, SkImageEncoder::Type> gEReg(sk_libwebp_efact ory);
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