aboutsummaryrefslogtreecommitdiffhomepage
path: root/tests/ImageDecodingTest.cpp
blob: 30665a6f8e57a4dd5c9b3cd6f3129542034fed2a (plain)
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
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612
613
614
615
616
617
618
619
620
621
622
623
624
625
626
627
628
629
630
631
632
633
634
635
636
637
638
639
640
641
642
643
644
645
646
647
648
649
650
651
652
653
654
655
656
657
658
659
660
661
662
663
664
665
666
667
668
669
670
671
672
673
674
675
676
677
678
679
680
681
682
683
684
685
686
687
688
689
690
691
692
693
694
695
696
697
698
699
700
701
702
703
704
705
706
707
708
709
710
711
712
713
714
715
716
717
718
719
720
721
722
723
724
725
726
727
728
729
730
731
732
733
734
735
736
737
738
739
740
741
742
743
744
745
746
747
748
749
750
751
752
753
754
755
756
757
758
759
760
761
762
763
764
765
766
767
768
769
770
771
772
773
774
775
776
777
778
779
780
781
782
783
784
785
786
787
788
789
790
791
792
793
794
795
796
797
798
799
800
801
802
803
804
805
806
807
808
809
810
811
812
813
814
815
816
817
818
819
/*
 * Copyright 2013 Google Inc.
 *
 * Use of this source code is governed by a BSD-style license that can be
 * found in the LICENSE file.
 */

#include "Resources.h"
#include "SkBitmap.h"
#include "SkCanvas.h"
#include "SkColor.h"
#include "SkColorPriv.h"
#include "SkData.h"
#include "SkDecodingImageGenerator.h"
#include "SkDiscardableMemoryPool.h"
#include "SkForceLinking.h"
#include "SkGradientShader.h"
#include "SkImageDecoder.h"
#include "SkImageEncoder.h"
#include "SkImageGeneratorPriv.h"
#include "SkImagePriv.h"
#include "SkOSFile.h"
#include "SkPoint.h"
#include "SkShader.h"
#include "SkStream.h"
#include "SkString.h"
#include "Test.h"

__SK_FORCE_IMAGE_DECODER_LINKING;

/**
 *  Interprets c as an unpremultiplied color, and returns the
 *  premultiplied equivalent.
 */
static SkPMColor premultiply_unpmcolor(SkPMColor c) {
    U8CPU a = SkGetPackedA32(c);
    U8CPU r = SkGetPackedR32(c);
    U8CPU g = SkGetPackedG32(c);
    U8CPU b = SkGetPackedB32(c);
    return SkPreMultiplyARGB(a, r, g, b);
}

/**
 *  Return true if this stream format should be skipped, due
 *  to do being an opaque format or not a valid format.
 */
static bool skip_image_format(SkImageDecoder::Format format) {
    switch (format) {
        case SkImageDecoder::kPNG_Format:
        case SkImageDecoder::kWEBP_Format:
            return false;
        // Skip unknown since it will not be decoded anyway.
        case SkImageDecoder::kUnknown_Format:
        // Technically ICO and BMP supports alpha channels, but our image
        // decoders do not, so skip them as well.
        case SkImageDecoder::kICO_Format:
        case SkImageDecoder::kBMP_Format:
        // KTX and ASTC are texture formats so it's not particularly clear how to 
        // decode the alpha from them.
        case SkImageDecoder::kKTX_Format:
        case SkImageDecoder::kASTC_Format:
        // The rest of these are opaque.
        case SkImageDecoder::kPKM_Format:
        case SkImageDecoder::kWBMP_Format:
        case SkImageDecoder::kGIF_Format:
        case SkImageDecoder::kJPEG_Format:
            return true;
    }
    SkASSERT(false);
    return true;
}

/**
 *  Test decoding an image in premultiplied mode and unpremultiplied mode and compare
 *  them.
 */
static void compare_unpremul(skiatest::Reporter* reporter, const SkString& filename) {
    // Decode a resource:
    SkBitmap bm8888;
    SkBitmap bm8888Unpremul;

    SkFILEStream stream(filename.c_str());

    SkImageDecoder::Format format = SkImageDecoder::GetStreamFormat(&stream);
    if (skip_image_format(format)) {
        return;
    }

    SkAutoTDelete<SkImageDecoder> decoder(SkImageDecoder::Factory(&stream));
    if (NULL == decoder.get()) {
        SkDebugf("couldn't decode %s\n", filename.c_str());
        return;
    }

    bool success = decoder->decode(&stream, &bm8888, kN32_SkColorType,
                                   SkImageDecoder::kDecodePixels_Mode);
    if (!success) {
        return;
    }

    success = stream.rewind();
    REPORTER_ASSERT(reporter, success);
    if (!success) {
        return;
    }

    decoder->setRequireUnpremultipliedColors(true);
    success = decoder->decode(&stream, &bm8888Unpremul, kN32_SkColorType,
                              SkImageDecoder::kDecodePixels_Mode);
    if (!success) {
        return;
    }

    bool dimensionsMatch = bm8888.width() == bm8888Unpremul.width()
                           && bm8888.height() == bm8888Unpremul.height();
    REPORTER_ASSERT(reporter, dimensionsMatch);
    if (!dimensionsMatch) {
        return;
    }

    // Only do the comparison if the two bitmaps are both 8888.
    if (bm8888.colorType() != kN32_SkColorType || bm8888Unpremul.colorType() != kN32_SkColorType) {
        return;
    }

    // Now compare the two bitmaps.
    for (int i = 0; i < bm8888.width(); ++i) {
        for (int j = 0; j < bm8888.height(); ++j) {
            // "c0" is the color of the premultiplied bitmap at (i, j).
            const SkPMColor c0 = *bm8888.getAddr32(i, j);
            // "c1" is the result of premultiplying the color of the unpremultiplied
            // bitmap at (i, j).
            const SkPMColor c1 = premultiply_unpmcolor(*bm8888Unpremul.getAddr32(i, j));
            // Compute the difference for each component.
            int da = SkAbs32(SkGetPackedA32(c0) - SkGetPackedA32(c1));
            int dr = SkAbs32(SkGetPackedR32(c0) - SkGetPackedR32(c1));
            int dg = SkAbs32(SkGetPackedG32(c0) - SkGetPackedG32(c1));
            int db = SkAbs32(SkGetPackedB32(c0) - SkGetPackedB32(c1));

            // Alpha component must be exactly the same.
            REPORTER_ASSERT(reporter, 0 == da);

            // Color components may not match exactly due to rounding error.
            REPORTER_ASSERT(reporter, dr <= 1);
            REPORTER_ASSERT(reporter, dg <= 1);
            REPORTER_ASSERT(reporter, db <= 1);
        }
    }
}

static void test_unpremul(skiatest::Reporter* reporter) {
    // This test cannot run if there is no resource path.
    SkString resourcePath = GetResourcePath();
    if (resourcePath.isEmpty()) {
        SkDebugf("Could not run unpremul test because resourcePath not specified.");
        return;
    }
    SkOSFile::Iter iter(resourcePath.c_str());
    SkString basename;
    if (iter.next(&basename)) {
        do {
            SkString filename = SkOSPath::Join(resourcePath.c_str(), basename.c_str());
            // SkDebugf("about to decode \"%s\"\n", filename.c_str());
            compare_unpremul(reporter, filename);
        } while (iter.next(&basename));
    } else {
        SkDebugf("Failed to find any files :(\n");
    }
}

#if defined(SK_BUILD_FOR_ANDROID) || defined(SK_BUILD_FOR_UNIX)
// Test that the alpha type is what we expect.
static void test_alphaType(skiatest::Reporter* reporter, const SkString& filename,
                           bool requireUnpremul) {
    SkBitmap bm;
    SkFILEStream stream(filename.c_str());

    SkAutoTDelete<SkImageDecoder> decoder(SkImageDecoder::Factory(&stream));
    if (NULL == decoder.get()) {
        return;
    }

    decoder->setRequireUnpremultipliedColors(requireUnpremul);

    // Decode just the bounds. This should always succeed.
    bool success = decoder->decode(&stream, &bm, kN32_SkColorType,
                                   SkImageDecoder::kDecodeBounds_Mode);
    REPORTER_ASSERT(reporter, success);
    if (!success) {
        return;
    }

    // Keep track of the alpha type for testing later. If the full decode
    // succeeds, the alpha type should be the same, unless the full decode
    // determined that the alpha type should actually be opaque, which may
    // not be known when only decoding the bounds.
    const SkAlphaType boundsAlphaType = bm.alphaType();

    // rewind should always succeed on SkFILEStream.
    success = stream.rewind();
    REPORTER_ASSERT(reporter, success);
    if (!success) {
        return;
    }

    success = decoder->decode(&stream, &bm, kN32_SkColorType, SkImageDecoder::kDecodePixels_Mode);

    if (!success) {
        // When the decoder is set to require unpremul, if it does not support
        // unpremul it will fail. This is the only reason the decode should
        // fail (since we know the files we are using to test can be decoded).
        REPORTER_ASSERT(reporter, requireUnpremul);
        return;
    }

    // The bounds decode should return with either the requested
    // premul/unpremul or opaque, if that value could be determined when only
    // decoding the bounds.
    if (requireUnpremul) {
        REPORTER_ASSERT(reporter, kUnpremul_SkAlphaType == boundsAlphaType
                                  || kOpaque_SkAlphaType == boundsAlphaType);
    } else {
        REPORTER_ASSERT(reporter, kPremul_SkAlphaType == boundsAlphaType
                                  || kOpaque_SkAlphaType == boundsAlphaType);
    }

    // When decoding the full image, the alpha type should match the one
    // returned by the bounds decode, unless the full decode determined that
    // the alpha type is actually opaque.
    REPORTER_ASSERT(reporter, bm.alphaType() == boundsAlphaType
                              || bm.alphaType() == kOpaque_SkAlphaType);
}

DEF_TEST(ImageDecoding_alphaType, reporter) {
    SkString resourcePath = GetResourcePath();
    if (resourcePath.isEmpty()) {
        SkDebugf("Could not run alphaType test because resourcePath not specified.");
        return;
    }

    SkOSFile::Iter iter(resourcePath.c_str());
    SkString basename;
    if (iter.next(&basename)) {
        do {
            SkString filename = SkOSPath::Join(resourcePath.c_str(), basename.c_str());
            for (int truth = 0; truth <= 1; ++truth) {
                test_alphaType(reporter, filename, SkToBool(truth));
            }
        } while (iter.next(&basename));
    } else {
        SkDebugf("Failed to find any files :(\n");
    }

}

// Using known images, test that decoding into unpremul and premul behave as expected.
DEF_TEST(ImageDecoding_unpremul, reporter) {
    SkString resourcePath = GetResourcePath();
    if (resourcePath.isEmpty()) {
        SkDebugf("Could not run unpremul test because resourcePath not specified.");
        return;
    }
    const char* root = "half-transparent-white-pixel";
    const char* suffixes[] = { ".png", ".webp" };

    for (size_t i = 0; i < SK_ARRAY_COUNT(suffixes); ++i) {
        SkString basename = SkStringPrintf("%s%s", root, suffixes[i]);
        SkString fullName = SkOSPath::Join(resourcePath.c_str(), basename.c_str());

        SkBitmap bm;
        SkFILEStream stream(fullName.c_str());

        if (!stream.isValid()) {
            SkDebugf("file %s missing from resource directoy %s\n",
                     basename.c_str(), resourcePath.c_str());
            continue;
        }

        // This should never fail since we know the images we're decoding.
        SkAutoTDelete<SkImageDecoder> decoder(SkImageDecoder::Factory(&stream));
        REPORTER_ASSERT(reporter, decoder.get());
        if (NULL == decoder.get()) {
            continue;
        }

        // Test unpremultiplied. We know what color this should result in.
        decoder->setRequireUnpremultipliedColors(true);
        bool success = decoder->decode(&stream, &bm, kN32_SkColorType,
                                       SkImageDecoder::kDecodePixels_Mode);
        REPORTER_ASSERT(reporter, success);
        if (!success) {
            continue;
        }

        REPORTER_ASSERT(reporter, bm.width() == 1 && bm.height() == 1);
        {
            SkAutoLockPixels alp(bm);
            REPORTER_ASSERT(reporter, bm.getAddr32(0, 0)[0] == 0x7fffffff);
        }

        success = stream.rewind();
        REPORTER_ASSERT(reporter, success);
        if (!success) {
            continue;
        }

        // Test premultiplied. Once again, we know which color this should
        // result in.
        decoder->setRequireUnpremultipliedColors(false);
        success = decoder->decode(&stream, &bm, kN32_SkColorType,
                                  SkImageDecoder::kDecodePixels_Mode);
        REPORTER_ASSERT(reporter, success);
        if (!success) {
            continue;
        }

        REPORTER_ASSERT(reporter, bm.width() == 1 && bm.height() == 1);
        {
            SkAutoLockPixels alp(bm);
            REPORTER_ASSERT(reporter, bm.getAddr32(0, 0)[0] == 0x7f7f7f7f);
        }
    }
}
#endif // SK_BUILD_FOR_UNIX/ANDROID skbug.com/2388

#ifdef SK_DEBUG
// Create a stream containing a bitmap encoded to Type type.
static SkMemoryStream* create_image_stream(SkImageEncoder::Type type) {
    SkBitmap bm;
    const int size = 50;
    bm.allocN32Pixels(size, size);
    SkCanvas canvas(bm);
    SkPoint points[2] = {
        { SkIntToScalar(0), SkIntToScalar(0) },
        { SkIntToScalar(size), SkIntToScalar(size) }
    };
    SkColor colors[2] = { SK_ColorWHITE, SK_ColorBLUE };
    SkShader* shader = SkGradientShader::CreateLinear(points, colors, NULL,
                                                      SK_ARRAY_COUNT(colors),
                                                      SkShader::kClamp_TileMode);
    SkPaint paint;
    paint.setShader(shader)->unref();
    canvas.drawPaint(paint);
    // Now encode it to a stream.
    SkAutoTUnref<SkData> data(SkImageEncoder::EncodeData(bm, type, 100));
    if (NULL == data.get()) {
        return NULL;
    }
    return SkNEW_ARGS(SkMemoryStream, (data.get()));
}

// For every format that supports tile based decoding, ensure that
// calling decodeSubset will not fail if the caller has unreffed the
// stream provided in buildTileIndex.
// Only runs in debug mode since we are testing for a crash.
static void test_stream_life() {
    const SkImageEncoder::Type gTypes[] = {
#ifdef SK_BUILD_FOR_ANDROID
        SkImageEncoder::kJPEG_Type,
        SkImageEncoder::kPNG_Type,
#endif
        SkImageEncoder::kWEBP_Type,
    };
    for (size_t i = 0; i < SK_ARRAY_COUNT(gTypes); ++i) {
        // SkDebugf("encoding to %i\n", i);
        SkAutoTUnref<SkMemoryStream> stream(create_image_stream(gTypes[i]));
        if (NULL == stream.get()) {
            SkDebugf("no stream\n");
            continue;
        }
        SkAutoTDelete<SkImageDecoder> decoder(SkImageDecoder::Factory(stream));
        if (NULL == decoder.get()) {
            SkDebugf("no decoder\n");
            continue;
        }
        int width, height;
        if (!decoder->buildTileIndex(stream.get(), &width, &height)) {
            SkDebugf("could not build a tile index\n");
            continue;
        }
        // Now unref the stream to make sure it survives
        stream.reset(NULL);
        SkBitmap bm;
        decoder->decodeSubset(&bm, SkIRect::MakeWH(width, height), kN32_SkColorType);
    }
}

// Test inside SkScaledBitmapSampler.cpp
extern void test_row_proc_choice();

#endif  // SK_DEBUG

DEF_TEST(ImageDecoding, reporter) {
    test_unpremul(reporter);
#ifdef SK_DEBUG
    test_stream_life();
    test_row_proc_choice();
#endif
}

// expected output for 8x8 bitmap
static const int kExpectedWidth = 8;
static const int kExpectedHeight = 8;
static const SkColor kExpectedPixels[] = {
    0xffbba570, 0xff395f5d, 0xffe25c39, 0xff197666,
    0xff3cba27, 0xffdefcb0, 0xffc13874, 0xfffa0093,
    0xffbda60e, 0xffc01db6, 0xff2bd688, 0xff9362d4,
    0xffc641b2, 0xffa5cede, 0xff606eba, 0xff8f4bf3,
    0xff3bf742, 0xff8f02a8, 0xff5509df, 0xffc7027e,
    0xff24aa8a, 0xff886c96, 0xff625481, 0xff403689,
    0xffc52152, 0xff78ccd6, 0xffdcb4ab, 0xff09d27d,
    0xffca00f3, 0xff605d47, 0xff446fb2, 0xff576e46,
    0xff273df9, 0xffb41a83, 0xfff812c3, 0xffccab67,
    0xff034218, 0xff7db9a7, 0xff821048, 0xfffe4ab4,
    0xff6fac98, 0xff941d27, 0xff5fe411, 0xfffbb283,
    0xffd86e99, 0xff169162, 0xff71128c, 0xff39cab4,
    0xffa7fe63, 0xff4c956b, 0xffbc22e0, 0xffb272e4,
    0xff129f4a, 0xffe34513, 0xff3d3742, 0xffbd190a,
    0xffb07222, 0xff2e23f8, 0xfff089d9, 0xffb35738,
    0xffa86022, 0xff3340fe, 0xff95fe71, 0xff6a71df
};
SK_COMPILE_ASSERT((kExpectedWidth * kExpectedHeight)
                  == SK_ARRAY_COUNT(kExpectedPixels), array_size_mismatch);

DEF_TEST(WebP, reporter) {
    const unsigned char encodedWebP[] = {
        0x52, 0x49, 0x46, 0x46, 0x2c, 0x01, 0x00, 0x00, 0x57, 0x45, 0x42, 0x50,
        0x56, 0x50, 0x38, 0x4c, 0x20, 0x01, 0x00, 0x00, 0x2f, 0x07, 0xc0, 0x01,
        0x00, 0xff, 0x01, 0x45, 0x03, 0x00, 0xe2, 0xd5, 0xae, 0x60, 0x2b, 0xad,
        0xd9, 0x68, 0x76, 0xb6, 0x8d, 0x6a, 0x1d, 0xc0, 0xe6, 0x19, 0xd6, 0x16,
        0xb7, 0xb4, 0xef, 0xcf, 0xc3, 0x15, 0x6c, 0xb3, 0xbd, 0x77, 0x0d, 0x85,
        0x6d, 0x1b, 0xa9, 0xb1, 0x2b, 0xdc, 0x3d, 0x83, 0xdb, 0x00, 0x00, 0xc8,
        0x26, 0xe5, 0x01, 0x99, 0x8a, 0xd5, 0xdd, 0xfc, 0x82, 0xcd, 0xcd, 0x9a,
        0x8c, 0x13, 0xcc, 0x1b, 0xba, 0xf5, 0x05, 0xdb, 0xee, 0x6a, 0xdb, 0x38,
        0x60, 0xfe, 0x43, 0x2c, 0xd4, 0x6a, 0x99, 0x4d, 0xc6, 0xc0, 0xd3, 0x28,
        0x1b, 0xc1, 0xb1, 0x17, 0x4e, 0x43, 0x0e, 0x3d, 0x27, 0xe9, 0xe4, 0x84,
        0x4f, 0x24, 0x62, 0x69, 0x85, 0x43, 0x8d, 0xc2, 0x04, 0x00, 0x07, 0x59,
        0x60, 0xfd, 0x8b, 0x4d, 0x60, 0x32, 0x72, 0xcf, 0x88, 0x0c, 0x2f, 0x2f,
        0xad, 0x62, 0xbd, 0x27, 0x09, 0x16, 0x70, 0x78, 0x6c, 0xd9, 0x82, 0xef,
        0x1a, 0xa2, 0xcc, 0xf0, 0xf1, 0x6f, 0xd8, 0x78, 0x2e, 0x39, 0xa1, 0xcf,
        0x14, 0x4b, 0x89, 0xb4, 0x1b, 0x48, 0x15, 0x7c, 0x48, 0x6f, 0x8c, 0x20,
        0xb7, 0x00, 0xcf, 0xfc, 0xdb, 0xd0, 0xe9, 0xe7, 0x42, 0x09, 0xa4, 0x03,
        0x40, 0xac, 0xda, 0x40, 0x01, 0x00, 0x5f, 0xa1, 0x3d, 0x64, 0xe1, 0xf4,
        0x03, 0x45, 0x29, 0xe0, 0xe2, 0x4a, 0xc3, 0xa2, 0xe8, 0xe0, 0x25, 0x12,
        0x74, 0xc6, 0xe8, 0xfb, 0x93, 0x4f, 0x9f, 0x5e, 0xc0, 0xa6, 0x91, 0x1b,
        0xa4, 0x24, 0x82, 0xc3, 0x61, 0x07, 0x4c, 0x49, 0x4f, 0x53, 0xae, 0x5f,
        0x5d, 0x39, 0x36, 0xc0, 0x5b, 0x57, 0x54, 0x60, 0x10, 0x00, 0x00, 0xd1,
        0x68, 0xb6, 0x6d, 0xdb, 0x36, 0x22, 0xfa, 0x1f, 0x35, 0x75, 0x22, 0xec,
        0x31, 0xbc, 0x5d, 0x8f, 0x87, 0x53, 0xa2, 0x05, 0x8c, 0x2f, 0xcd, 0xa8,
        0xa7, 0xf3, 0xa3, 0xbd, 0x83, 0x8b, 0x2a, 0xc8, 0x58, 0xf5, 0xac, 0x80,
        0xe3, 0xfe, 0x66, 0xa4, 0x7c, 0x1b, 0x6c, 0xd1, 0xa9, 0xd8, 0x14, 0xd0,
        0xc5, 0xb5, 0x39, 0x71, 0x97, 0x19, 0x19, 0x1b
    };
    SkAutoDataUnref encoded(SkData::NewWithCopy(encodedWebP,
                                                sizeof(encodedWebP)));
    SkBitmap bm;

    bool success = SkInstallDiscardablePixelRef(
        SkDecodingImageGenerator::Create(encoded,
            SkDecodingImageGenerator::Options()), &bm);

    REPORTER_ASSERT(reporter, success);
    if (!success) {
        return;
    }
    SkAutoLockPixels alp(bm);

    bool rightSize = ((kExpectedWidth == bm.width())
                      && (kExpectedHeight == bm.height()));
    REPORTER_ASSERT(reporter, rightSize);
    if (rightSize) {
        bool error = false;
        const SkColor* correctPixel = kExpectedPixels;
        for (int y = 0; y < bm.height(); ++y) {
            for (int x = 0; x < bm.width(); ++x) {
                error |= (*correctPixel != bm.getColor(x, y));
                ++correctPixel;
            }
        }
        REPORTER_ASSERT(reporter, !error);
    }
}

////////////////////////////////////////////////////////////////////////////////

// example of how Android will do this inside their BitmapFactory
static SkPixelRef* install_pixel_ref(SkBitmap* bitmap,
                                     SkStreamRewindable* stream,
                                     int sampleSize, bool ditherImage) {
    SkASSERT(bitmap != NULL);
    SkASSERT(stream != NULL);
    SkASSERT(stream->rewind());
    SkASSERT(stream->unique());
    SkColorType colorType = bitmap->colorType();
    SkDecodingImageGenerator::Options opts(sampleSize, ditherImage, colorType);
    if (SkInstallDiscardablePixelRef(
                SkDecodingImageGenerator::Create(stream, opts), bitmap)) {
        return bitmap->pixelRef();
    }
    return NULL;
}
/**
 *  A test for the SkDecodingImageGenerator::Create and
 *  SkInstallDiscardablePixelRef functions.
 */
DEF_TEST(ImprovedBitmapFactory, reporter) {
    SkString pngFilename = GetResourcePath("randPixels.png");
    SkAutoTUnref<SkStreamRewindable> stream(SkStream::NewFromFile(pngFilename.c_str()));
    if (sk_exists(pngFilename.c_str())) {
        SkBitmap bm;
        SkAssertResult(bm.setInfo(SkImageInfo::MakeN32Premul(1, 1)));
        REPORTER_ASSERT(reporter,
            install_pixel_ref(&bm, stream.detach(), 1, true));
        SkAutoLockPixels alp(bm);
        REPORTER_ASSERT(reporter, bm.getPixels());
    }
}


////////////////////////////////////////////////////////////////////////////////

#if defined(SK_BUILD_FOR_ANDROID) || defined(SK_BUILD_FOR_UNIX)
static inline bool check_rounding(int value, int dividend, int divisor) {
    // returns true if the value is greater than floor(dividend/divisor)
    // and less than SkNextPow2(ceil(dividend - divisor))
    return (((divisor * value) > (dividend - divisor))
            && value <= SkNextPow2(((dividend - 1) / divisor) + 1));
}
#endif  // SK_BUILD_FOR_ANDROID || SK_BUILD_FOR_UNIX


#if SK_PMCOLOR_BYTE_ORDER(B,G,R,A)
    #define kBackwards_SkColorType kRGBA_8888_SkColorType
#elif SK_PMCOLOR_BYTE_ORDER(R,G,B,A)
    #define kBackwards_SkColorType kBGRA_8888_SkColorType
#else
    #error "SK_*32_SHFIT values must correspond to BGRA or RGBA byte order"
#endif

static inline const char* SkColorType_to_string(SkColorType colorType) {
    switch(colorType) {
        case kAlpha_8_SkColorType:   return "Alpha_8";
        case kRGB_565_SkColorType:   return "RGB_565";
        case kARGB_4444_SkColorType: return "ARGB_4444";
        case kN32_SkColorType:       return "N32";
        case kBackwards_SkColorType: return "Backwards";
        case kIndex_8_SkColorType:   return "Index_8";
        default:                     return "ERROR";
    }
}

static inline const char* options_colorType(
        const SkDecodingImageGenerator::Options& opts) {
    if (opts.fUseRequestedColorType) {
        return SkColorType_to_string(opts.fRequestedColorType);
    } else {
        return "(none)";
    }
}

static inline const char* yn(bool value) {
    if (value) {
        return "yes";
    } else {
        return "no";
    }
}

/**
 * Given either a SkStream or a SkData, try to decode the encoded
 * image using the specified options and report errors.
 */
static void test_options(skiatest::Reporter* reporter,
                         const SkDecodingImageGenerator::Options& opts,
                         SkStreamRewindable* encodedStream,
                         SkData* encodedData,
                         bool useData,
                         const SkString& path) {
    SkBitmap bm;
    bool success = false;
    if (useData) {
        if (NULL == encodedData) {
            return;
        }
        success = SkInstallDiscardablePixelRef(
            SkDecodingImageGenerator::Create(encodedData, opts), &bm);
    } else {
        if (NULL == encodedStream) {
            return;
        }
        success = SkInstallDiscardablePixelRef(
            SkDecodingImageGenerator::Create(encodedStream->duplicate(), opts), &bm);
    }
    if (!success) {
        if (opts.fUseRequestedColorType
            && (kARGB_4444_SkColorType == opts.fRequestedColorType)) {
            return;  // Ignore known conversion inabilities.
        }
        // If we get here, it's a failure and we will need more
        // information about why it failed.
        ERRORF(reporter, "Bounds decode failed [sampleSize=%d dither=%s "
               "colorType=%s %s]", opts.fSampleSize, yn(opts.fDitherImage),
               options_colorType(opts), path.c_str());
        return;
    }
    #if defined(SK_BUILD_FOR_ANDROID) || defined(SK_BUILD_FOR_UNIX)
    // Android is the only system that use Skia's image decoders in
    // production.  For now, we'll only verify that samplesize works
    // on systems where it already is known to work.
    REPORTER_ASSERT(reporter, check_rounding(bm.height(), kExpectedHeight,
                                             opts.fSampleSize));
    REPORTER_ASSERT(reporter, check_rounding(bm.width(), kExpectedWidth,
                                             opts.fSampleSize));
    // The ImageDecoder API doesn't guarantee that SampleSize does
    // anything at all, but the decoders that this test excercises all
    // produce an output size in the following range:
    //    (((sample_size * out_size) > (in_size - sample_size))
    //     && out_size <= SkNextPow2(((in_size - 1) / sample_size) + 1));
    #endif  // SK_BUILD_FOR_ANDROID || SK_BUILD_FOR_UNIX
    SkAutoLockPixels alp(bm);
    if (bm.getPixels() == NULL) {
        ERRORF(reporter, "Pixel decode failed [sampleSize=%d dither=%s "
               "colorType=%s %s]", opts.fSampleSize, yn(opts.fDitherImage),
               options_colorType(opts), path.c_str());
        return;
    }

    SkColorType requestedColorType = opts.fRequestedColorType;
    REPORTER_ASSERT(reporter,
                    (!opts.fUseRequestedColorType)
                    || (bm.colorType() == requestedColorType));

    // Condition under which we should check the decoding results:
    if ((kN32_SkColorType == bm.colorType())
        && (!path.endsWith(".jpg"))  // lossy
        && (opts.fSampleSize == 1)) {  // scaled
        const SkColor* correctPixels = kExpectedPixels;
        SkASSERT(bm.height() == kExpectedHeight);
        SkASSERT(bm.width() == kExpectedWidth);
        int pixelErrors = 0;
        for (int y = 0; y < bm.height(); ++y) {
            for (int x = 0; x < bm.width(); ++x) {
                if (*correctPixels != bm.getColor(x, y)) {
                    ++pixelErrors;
                }
                ++correctPixels;
            }
        }
        if (pixelErrors != 0) {
            ERRORF(reporter, "Pixel-level mismatch (%d of %d) "
                   "[sampleSize=%d dither=%s colorType=%s %s]",
                   pixelErrors, kExpectedHeight * kExpectedWidth,
                   opts.fSampleSize, yn(opts.fDitherImage),
                   options_colorType(opts), path.c_str());
        }
    }
}

/**
 *  SkDecodingImageGenerator has an Options struct which lets the
 *  client of the generator set sample size, dithering, and bitmap
 *  config.  This test loops through many possible options and tries
 *  them on a set of 5 small encoded images (each in a different
 *  format).  We test both SkData and SkStreamRewindable decoding.
 */
DEF_TEST(ImageDecoderOptions, reporter) {
    const char* files[]  = {
        "randPixels.bmp",
        "randPixels.jpg",
        "randPixels.png",
        "randPixels.webp",
        #if !defined(SK_BUILD_FOR_WIN)
        // TODO(halcanary): Find out why this fails sometimes.
        "randPixels.gif",
        #endif
    };

    SkString resourceDir = GetResourcePath();
    if (!sk_exists(resourceDir.c_str())) {
        return;
    }

    int scaleList[] = {1, 2, 3, 4};
    bool ditherList[] = {true, false};
    SkColorType colorList[] = {
        kAlpha_8_SkColorType,
        kRGB_565_SkColorType,
        kARGB_4444_SkColorType,  // Most decoders will fail on 4444.
        kN32_SkColorType
        // Note that indexed color is left out of the list.  Lazy
        // decoding doesn't do indexed color.
    };
    const bool useDataList[] = {true, false};

    for (size_t fidx = 0; fidx < SK_ARRAY_COUNT(files); ++fidx) {
        SkString path = SkOSPath::Join(resourceDir.c_str(), files[fidx]);
        if (!sk_exists(path.c_str())) {
            continue;
        }

        SkAutoDataUnref encodedData(SkData::NewFromFileName(path.c_str()));
        REPORTER_ASSERT(reporter, encodedData.get() != NULL);
        SkAutoTUnref<SkStreamRewindable> encodedStream(
            SkStream::NewFromFile(path.c_str()));
        REPORTER_ASSERT(reporter, encodedStream.get() != NULL);

        for (size_t i = 0; i < SK_ARRAY_COUNT(scaleList); ++i) {
            for (size_t j = 0; j < SK_ARRAY_COUNT(ditherList); ++j) {
                for (size_t m = 0; m < SK_ARRAY_COUNT(useDataList); ++m) {
                    for (size_t k = 0; k < SK_ARRAY_COUNT(colorList); ++k) {
                        SkDecodingImageGenerator::Options opts(scaleList[i],
                                                               ditherList[j],
                                                               colorList[k]);
                        test_options(reporter, opts, encodedStream, encodedData,
                                     useDataList[m], path);

                    }
                    SkDecodingImageGenerator::Options options(scaleList[i],
                                                              ditherList[j]);
                    test_options(reporter, options, encodedStream, encodedData,
                                 useDataList[m], path);
                }
            }
        }
    }
}

DEF_TEST(DiscardablePixelRef_SecondLockColorTableCheck, r) {
    SkString resourceDir = GetResourcePath();
    SkString path = SkOSPath::Join(resourceDir.c_str(), "randPixels.gif");
    if (!sk_exists(path.c_str())) {
        return;
    }
    SkAutoDataUnref encoded(SkData::NewFromFileName(path.c_str()));
    SkBitmap bitmap;
    if (!SkInstallDiscardablePixelRef(
            SkDecodingImageGenerator::Create(
                    encoded, SkDecodingImageGenerator::Options()), &bitmap)) {
        #ifndef SK_BUILD_FOR_WIN
        ERRORF(r, "SkInstallDiscardablePixelRef [randPixels.gif] failed.");
        #endif
        return;
    }
    if (kIndex_8_SkColorType != bitmap.colorType()) {
        return;
    }
    {
        SkAutoLockPixels alp(bitmap);
        REPORTER_ASSERT(r, bitmap.getColorTable() && "first pass");
    }
    {
        SkAutoLockPixels alp(bitmap);
        REPORTER_ASSERT(r, bitmap.getColorTable() && "second pass");
    }
}


////////////////////////////////////////////////////////////////////////////////
namespace {
class SingleAllocator : public SkBitmap::Allocator {
public:
    SingleAllocator(void* p, size_t s) : fPixels(p), fSize(s) { }
    ~SingleAllocator() {}
    // If the pixels in fPixels are big enough, use them.
    virtual bool allocPixelRef(SkBitmap* bm, SkColorTable* ct) SK_OVERRIDE {
        SkASSERT(bm);
        if (bm->info().getSafeSize(bm->rowBytes()) <= fSize) {
            bm->setPixels(fPixels, ct);
            fPixels = NULL;
            fSize = 0;
            return true;
        }
        return bm->tryAllocPixels(NULL, ct);
    }
    bool ready() { return fPixels != NULL; }
private:
    void* fPixels;
    size_t fSize;
};
}  // namespace

/*  This tests for a bug in libjpeg where INT32 is typedefed to long
    and memory can be written to outside of the array. */
DEF_TEST(ImageDecoding_JpegOverwrite, r) {
    SkString resourceDir = GetResourcePath();
    SkString path = SkOSPath::Join(resourceDir.c_str(), "randPixels.jpg");
    SkAutoTUnref<SkStreamAsset> stream(
            SkStream::NewFromFile(path.c_str()));
    if (!stream.get()) {
        SkDebugf("\nPath '%s' missing.\n", path.c_str());
        return;
    }
    SkAutoTDelete<SkImageDecoder> decoder(SkImageDecoder::Factory(stream));
    if (NULL == decoder.get()) {
        ERRORF(r, "\nSkImageDecoder::Factory failed.\n");
        return;
    }
    SkAssertResult(stream->rewind());

    static const uint16_t sentinal = 0xBEEF;
    static const int pixelCount = 16;
    SkAutoTMalloc<uint16_t> pixels(pixelCount + 1);
    // pixels.get() should be 4-byte aligned.
    // This is necessary to reproduce the bug.

    pixels[pixelCount] = sentinal;  // This value should not be changed.

    SkAutoTUnref<SingleAllocator> allocator(
            SkNEW_ARGS(SingleAllocator,
                       ((void*)pixels.get(), sizeof(uint16_t) * pixelCount)));
    decoder->setAllocator(allocator);
    decoder->setSampleSize(2);
    SkBitmap bitmap;
    bool success = decoder->decode(stream, &bitmap, kRGB_565_SkColorType,
                                   SkImageDecoder::kDecodePixels_Mode);
    REPORTER_ASSERT(r, success);
    REPORTER_ASSERT(r, !allocator->ready());  // Decoder used correct memory
    REPORTER_ASSERT(r, sentinal == pixels[pixelCount]);
}