xref: /third_party/skia/tests/ReadPixelsTest.cpp (revision cb93a386) 
1/*
2 * Copyright 2011 Google Inc.
3 *
4 * Use of this source code is governed by a BSD-style license that can be
5 * found in the LICENSE file.
6 */
7
8#include "include/core/SkCanvas.h"
9#include "include/core/SkColorPriv.h"
10#include "include/core/SkImage.h"
11#include "include/core/SkSurface.h"
12#include "include/private/SkColorData.h"
13#include "include/private/SkHalf.h"
14#include "include/private/SkImageInfoPriv.h"
15#include "include/utils/SkNWayCanvas.h"
16#include "src/core/SkMathPriv.h"
17#include "tests/Test.h"
18
19static const int DEV_W = 100, DEV_H = 100;
20static const SkIRect DEV_RECT = SkIRect::MakeWH(DEV_W, DEV_H);
21static const SkRect DEV_RECT_S = SkRect::MakeWH(DEV_W * SK_Scalar1,
22                                                DEV_H * SK_Scalar1);
23
24static SkPMColor get_src_color(int x, int y) {
25    SkASSERT(x >= 0 && x < DEV_W);
26    SkASSERT(y >= 0 && y < DEV_H);
27
28    U8CPU r = x;
29    U8CPU g = y;
30    U8CPU b = 0xc;
31
32    U8CPU a = 0xff;
33    switch ((x+y) % 5) {
34        case 0:
35            a = 0xff;
36            break;
37        case 1:
38            a = 0x80;
39            break;
40        case 2:
41            a = 0xCC;
42            break;
43        case 4:
44            a = 0x01;
45            break;
46        case 3:
47            a = 0x00;
48            break;
49    }
50    return SkPremultiplyARGBInline(a, r, g, b);
51}
52
53static SkPMColor get_dst_bmp_init_color(int x, int y, int w) {
54    int n = y * w + x;
55
56    U8CPU b = n & 0xff;
57    U8CPU g = (n >> 8) & 0xff;
58    U8CPU r = (n >> 16) & 0xff;
59    return SkPackARGB32(0xff, r, g , b);
60}
61
62// TODO: Make this consider both ATs
63static SkPMColor convert_to_pmcolor(SkColorType ct, SkAlphaType at, const uint32_t* addr,
64                                    bool* doUnpremul) {
65    *doUnpremul = (kUnpremul_SkAlphaType == at);
66
67    const uint8_t* c = reinterpret_cast<const uint8_t*>(addr);
68    U8CPU a,r,g,b;
69    switch (ct) {
70        case kBGRA_8888_SkColorType:
71            b = static_cast<U8CPU>(c[0]);
72            g = static_cast<U8CPU>(c[1]);
73            r = static_cast<U8CPU>(c[2]);
74            a = static_cast<U8CPU>(c[3]);
75            break;
76        case kRGB_888x_SkColorType:  // fallthrough
77        case kRGBA_8888_SkColorType:
78            r = static_cast<U8CPU>(c[0]);
79            g = static_cast<U8CPU>(c[1]);
80            b = static_cast<U8CPU>(c[2]);
81            // We set this even when for kRGB_888x because our caller will validate that it is 0xff.
82            a = static_cast<U8CPU>(c[3]);
83            break;
84        default:
85            SkDEBUGFAIL("Unexpected colortype");
86            return 0;
87    }
88
89    if (*doUnpremul) {
90        r = SkMulDiv255Ceiling(r, a);
91        g = SkMulDiv255Ceiling(g, a);
92        b = SkMulDiv255Ceiling(b, a);
93    }
94    return SkPackARGB32(a, r, g, b);
95}
96
97static sk_sp<SkImage> make_src_image() {
98    static SkBitmap bmp;
99    if (bmp.isNull()) {
100        bmp.allocN32Pixels(DEV_W, DEV_H);
101        intptr_t pixels = reinterpret_cast<intptr_t>(bmp.getPixels());
102        for (int y = 0; y < DEV_H; ++y) {
103            for (int x = 0; x < DEV_W; ++x) {
104                SkPMColor* pixel = reinterpret_cast<SkPMColor*>(pixels + y * bmp.rowBytes() + x * bmp.bytesPerPixel());
105                *pixel = get_src_color(x, y);
106            }
107        }
108        bmp.setImmutable();
109    }
110    return bmp.asImage();
111}
112
113static void fill_src_canvas(SkCanvas* canvas) {
114    canvas->save();
115    canvas->setMatrix(SkMatrix::I());
116    canvas->clipRect(DEV_RECT_S, SkClipOp::kIntersect);
117    SkPaint paint;
118    paint.setBlendMode(SkBlendMode::kSrc);
119    canvas->drawImage(make_src_image(), 0, 0, SkSamplingOptions(), &paint);
120    canvas->restore();
121}
122
123static void fill_dst_bmp_with_init_data(SkBitmap* bitmap) {
124    int w = bitmap->width();
125    int h = bitmap->height();
126    intptr_t pixels = reinterpret_cast<intptr_t>(bitmap->getPixels());
127    for (int y = 0; y < h; ++y) {
128        for (int x = 0; x < w; ++x) {
129            SkPMColor initColor = get_dst_bmp_init_color(x, y, w);
130            if (kAlpha_8_SkColorType == bitmap->colorType()) {
131                uint8_t* alpha = reinterpret_cast<uint8_t*>(pixels + y * bitmap->rowBytes() + x);
132                *alpha = SkGetPackedA32(initColor);
133            } else {
134                SkPMColor* pixel = reinterpret_cast<SkPMColor*>(pixels + y * bitmap->rowBytes() + x * bitmap->bytesPerPixel());
135                *pixel = initColor;
136            }
137        }
138    }
139}
140
141static bool check_read_pixel(SkPMColor a, SkPMColor b, bool didPremulConversion) {
142    if (!didPremulConversion) {
143        return a == b;
144    }
145    int32_t aA = static_cast<int32_t>(SkGetPackedA32(a));
146    int32_t aR = static_cast<int32_t>(SkGetPackedR32(a));
147    int32_t aG = static_cast<int32_t>(SkGetPackedG32(a));
148    int32_t aB = SkGetPackedB32(a);
149
150    int32_t bA = static_cast<int32_t>(SkGetPackedA32(b));
151    int32_t bR = static_cast<int32_t>(SkGetPackedR32(b));
152    int32_t bG = static_cast<int32_t>(SkGetPackedG32(b));
153    int32_t bB = static_cast<int32_t>(SkGetPackedB32(b));
154
155    return aA == bA &&
156           SkAbs32(aR - bR) <= 1 &&
157           SkAbs32(aG - bG) <= 1 &&
158           SkAbs32(aB - bB) <= 1;
159}
160
161// checks the bitmap contains correct pixels after the readPixels
162// if the bitmap was prefilled with pixels it checks that these weren't
163// overwritten in the area outside the readPixels.
164static bool check_read(skiatest::Reporter* reporter, const SkBitmap& bitmap, int x, int y,
165                       bool checkSurfacePixels, bool checkBitmapPixels,
166                       SkImageInfo surfaceInfo) {
167    SkAlphaType bmpAT = bitmap.alphaType();
168    SkColorType bmpCT = bitmap.colorType();
169    SkASSERT(!bitmap.isNull());
170    SkASSERT(checkSurfacePixels || checkBitmapPixels);
171
172    int bw = bitmap.width();
173    int bh = bitmap.height();
174
175    SkIRect srcRect = SkIRect::MakeXYWH(x, y, bw, bh);
176    SkIRect clippedSrcRect = DEV_RECT;
177    if (!clippedSrcRect.intersect(srcRect)) {
178        clippedSrcRect.setEmpty();
179    }
180    if (kAlpha_8_SkColorType == bmpCT) {
181        for (int by = 0; by < bh; ++by) {
182            for (int bx = 0; bx < bw; ++bx) {
183                int devx = bx + srcRect.fLeft;
184                int devy = by + srcRect.fTop;
185                const uint8_t* alpha = bitmap.getAddr8(bx, by);
186
187                if (clippedSrcRect.contains(devx, devy)) {
188                    if (checkSurfacePixels) {
189                        uint8_t surfaceAlpha = (surfaceInfo.alphaType() == kOpaque_SkAlphaType)
190                                                       ? 0xFF
191                                                       : SkGetPackedA32(get_src_color(devx, devy));
192                        if (surfaceAlpha != *alpha) {
193                            ERRORF(reporter,
194                                   "Expected readback alpha (%d, %d) value 0x%02x, got 0x%02x. ",
195                                   bx, by, surfaceAlpha, *alpha);
196                            return false;
197                        }
198                    }
199                } else if (checkBitmapPixels) {
200                    uint32_t origDstAlpha = SkGetPackedA32(get_dst_bmp_init_color(bx, by, bw));
201                    if (origDstAlpha != *alpha) {
202                        ERRORF(reporter, "Expected clipped out area of readback to be unchanged. "
203                            "Expected 0x%02x, got 0x%02x", origDstAlpha, *alpha);
204                        return false;
205                    }
206                }
207            }
208        }
209        return true;
210    }
211    for (int by = 0; by < bh; ++by) {
212        for (int bx = 0; bx < bw; ++bx) {
213            int devx = bx + srcRect.fLeft;
214            int devy = by + srcRect.fTop;
215
216            const uint32_t* pixel = bitmap.getAddr32(bx, by);
217
218            if (clippedSrcRect.contains(devx, devy)) {
219                if (checkSurfacePixels) {
220                    SkPMColor surfacePMColor = get_src_color(devx, devy);
221                    if (SkColorTypeIsAlphaOnly(surfaceInfo.colorType())) {
222                        surfacePMColor &= 0xFF000000;
223                    }
224                    if (kOpaque_SkAlphaType == surfaceInfo.alphaType() || kOpaque_SkAlphaType == bmpAT) {
225                        surfacePMColor |= 0xFF000000;
226                    }
227                    bool didPremul;
228                    SkPMColor pmPixel = convert_to_pmcolor(bmpCT, bmpAT, pixel, &didPremul);
229                    if (!check_read_pixel(pmPixel, surfacePMColor, didPremul)) {
230                        ERRORF(reporter,
231                               "Expected readback pixel (%d, %d) value 0x%08x, got 0x%08x. "
232                               "Readback was unpremul: %d",
233                               bx, by, surfacePMColor, pmPixel, didPremul);
234                        return false;
235                    }
236                }
237            } else if (checkBitmapPixels) {
238                uint32_t origDstPixel = get_dst_bmp_init_color(bx, by, bw);
239                if (origDstPixel != *pixel) {
240                    ERRORF(reporter, "Expected clipped out area of readback to be unchanged. "
241                           "Expected 0x%08x, got 0x%08x", origDstPixel, *pixel);
242                    return false;
243                }
244            }
245        }
246    }
247    return true;
248}
249
250enum class TightRowBytes : bool { kNo, kYes };
251
252static void init_bitmap(SkBitmap* bitmap, const SkIRect& rect, TightRowBytes tightRB,
253                        SkColorType ct, SkAlphaType at) {
254    SkImageInfo info = SkImageInfo::Make(rect.size(), ct, at);
255    size_t rowBytes = 0;
256    if (tightRB == TightRowBytes::kNo) {
257        rowBytes = SkAlign4((info.width() + 16) * info.bytesPerPixel());
258    }
259    bitmap->allocPixels(info, rowBytes);
260}
261
262static const struct {
263    SkColorType fColorType;
264    SkAlphaType fAlphaType;
265} gReadPixelsConfigs[] = {
266        {kRGBA_8888_SkColorType, kPremul_SkAlphaType},
267        {kRGBA_8888_SkColorType, kUnpremul_SkAlphaType},
268        {kRGB_888x_SkColorType, kOpaque_SkAlphaType},
269        {kBGRA_8888_SkColorType, kPremul_SkAlphaType},
270        {kBGRA_8888_SkColorType, kUnpremul_SkAlphaType},
271        {kAlpha_8_SkColorType, kPremul_SkAlphaType},
272};
273const SkIRect gReadPixelsTestRects[] = {
274    // entire thing
275    DEV_RECT,
276    // larger on all sides
277    SkIRect::MakeLTRB(-10, -10, DEV_W + 10, DEV_H + 10),
278    // fully contained
279    SkIRect::MakeLTRB(DEV_W / 4, DEV_H / 4, 3 * DEV_W / 4, 3 * DEV_H / 4),
280    // outside top left
281    SkIRect::MakeLTRB(-10, -10, -1, -1),
282    // touching top left corner
283    SkIRect::MakeLTRB(-10, -10, 0, 0),
284    // overlapping top left corner
285    SkIRect::MakeLTRB(-10, -10, DEV_W / 4, DEV_H / 4),
286    // overlapping top left and top right corners
287    SkIRect::MakeLTRB(-10, -10, DEV_W  + 10, DEV_H / 4),
288    // touching entire top edge
289    SkIRect::MakeLTRB(-10, -10, DEV_W  + 10, 0),
290    // overlapping top right corner
291    SkIRect::MakeLTRB(3 * DEV_W / 4, -10, DEV_W  + 10, DEV_H / 4),
292    // contained in x, overlapping top edge
293    SkIRect::MakeLTRB(DEV_W / 4, -10, 3 * DEV_W  / 4, DEV_H / 4),
294    // outside top right corner
295    SkIRect::MakeLTRB(DEV_W + 1, -10, DEV_W + 10, -1),
296    // touching top right corner
297    SkIRect::MakeLTRB(DEV_W, -10, DEV_W + 10, 0),
298    // overlapping top left and bottom left corners
299    SkIRect::MakeLTRB(-10, -10, DEV_W / 4, DEV_H + 10),
300    // touching entire left edge
301    SkIRect::MakeLTRB(-10, -10, 0, DEV_H + 10),
302    // overlapping bottom left corner
303    SkIRect::MakeLTRB(-10, 3 * DEV_H / 4, DEV_W / 4, DEV_H + 10),
304    // contained in y, overlapping left edge
305    SkIRect::MakeLTRB(-10, DEV_H / 4, DEV_W / 4, 3 * DEV_H / 4),
306    // outside bottom left corner
307    SkIRect::MakeLTRB(-10, DEV_H + 1, -1, DEV_H + 10),
308    // touching bottom left corner
309    SkIRect::MakeLTRB(-10, DEV_H, 0, DEV_H + 10),
310    // overlapping bottom left and bottom right corners
311    SkIRect::MakeLTRB(-10, 3 * DEV_H / 4, DEV_W + 10, DEV_H + 10),
312    // touching entire left edge
313    SkIRect::MakeLTRB(0, DEV_H, DEV_W, DEV_H + 10),
314    // overlapping bottom right corner
315    SkIRect::MakeLTRB(3 * DEV_W / 4, 3 * DEV_H / 4, DEV_W + 10, DEV_H + 10),
316    // overlapping top right and bottom right corners
317    SkIRect::MakeLTRB(3 * DEV_W / 4, -10, DEV_W + 10, DEV_H + 10),
318};
319
320bool read_should_succeed(const SkIRect& srcRect, const SkImageInfo& dstInfo,
321                         const SkImageInfo& srcInfo) {
322    return SkIRect::Intersects(srcRect, DEV_RECT) && SkImageInfoValidConversion(dstInfo, srcInfo);
323}
324
325static void test_readpixels(skiatest::Reporter* reporter, const sk_sp<SkSurface>& surface,
326                            const SkImageInfo& surfaceInfo) {
327    SkCanvas* canvas = surface->getCanvas();
328    fill_src_canvas(canvas);
329    for (size_t rect = 0; rect < SK_ARRAY_COUNT(gReadPixelsTestRects); ++rect) {
330        const SkIRect& srcRect = gReadPixelsTestRects[rect];
331        for (auto tightRB : {TightRowBytes::kYes, TightRowBytes::kNo}) {
332            for (size_t c = 0; c < SK_ARRAY_COUNT(gReadPixelsConfigs); ++c) {
333                SkBitmap bmp;
334                init_bitmap(&bmp, srcRect, tightRB, gReadPixelsConfigs[c].fColorType,
335                            gReadPixelsConfigs[c].fAlphaType);
336
337                // if the bitmap has pixels allocated before the readPixels,
338                // note that and fill them with pattern
339                bool startsWithPixels = !bmp.isNull();
340                if (startsWithPixels) {
341                    fill_dst_bmp_with_init_data(&bmp);
342                }
343                uint32_t idBefore = surface->generationID();
344                bool success = surface->readPixels(bmp, srcRect.fLeft, srcRect.fTop);
345                uint32_t idAfter = surface->generationID();
346
347                // we expect to succeed when the read isn't fully clipped out and the infos are
348                // compatible.
349                bool expectSuccess = read_should_succeed(srcRect, bmp.info(), surfaceInfo);
350                // determine whether we expected the read to succeed.
351                REPORTER_ASSERT(reporter, expectSuccess == success,
352                                "Read succeed=%d unexpectedly, src ct/at: %d/%d, dst ct/at: %d/%d",
353                                success, surfaceInfo.colorType(), surfaceInfo.alphaType(),
354                                bmp.info().colorType(), bmp.info().alphaType());
355                // read pixels should never change the gen id
356                REPORTER_ASSERT(reporter, idBefore == idAfter);
357
358                if (success || startsWithPixels) {
359                    check_read(reporter, bmp, srcRect.fLeft, srcRect.fTop, success,
360                               startsWithPixels, surfaceInfo);
361                } else {
362                    // if we had no pixels beforehand and the readPixels
363                    // failed then our bitmap should still not have pixels
364                    REPORTER_ASSERT(reporter, bmp.isNull());
365                }
366            }
367        }
368    }
369}
370
371DEF_TEST(ReadPixels, reporter) {
372    const SkImageInfo info = SkImageInfo::MakeN32Premul(DEV_W, DEV_H);
373    auto surface(SkSurface::MakeRaster(info));
374    test_readpixels(reporter, surface, info);
375}
376
377///////////////////////////////////////////////////////////////////////////////////////////////////
378
379static const uint32_t kNumPixels = 5;
380
381// The five reference pixels are: red, green, blue, white, black.
382// Five is an interesting number to test because we'll exercise a full 4-wide SIMD vector
383// plus a tail pixel.
384static const uint32_t rgba[kNumPixels] = {
385        0xFF0000FF, 0xFF00FF00, 0xFFFF0000, 0xFFFFFFFF, 0xFF000000
386};
387static const uint32_t bgra[kNumPixels] = {
388        0xFFFF0000, 0xFF00FF00, 0xFF0000FF, 0xFFFFFFFF, 0xFF000000
389};
390static const uint16_t rgb565[kNumPixels] = {
391        SK_R16_MASK_IN_PLACE, SK_G16_MASK_IN_PLACE, SK_B16_MASK_IN_PLACE, 0xFFFF, 0x0
392};
393
394static const uint16_t rgba4444[kNumPixels] = { 0xF00F, 0x0F0F, 0x00FF, 0xFFFF, 0x000F };
395
396static const uint64_t kRed      = (uint64_t) SK_Half1 <<  0;
397static const uint64_t kGreen    = (uint64_t) SK_Half1 << 16;
398static const uint64_t kBlue     = (uint64_t) SK_Half1 << 32;
399static const uint64_t kAlpha    = (uint64_t) SK_Half1 << 48;
400static const uint64_t f16[kNumPixels] = {
401        kAlpha | kRed, kAlpha | kGreen, kAlpha | kBlue, kAlpha | kBlue | kGreen | kRed, kAlpha
402};
403
404static const uint8_t alpha8[kNumPixels] = { 0xFF, 0xFF, 0xFF, 0xFF, 0xFF };
405static const uint8_t gray8[kNumPixels] = { 0xFF, 0xFF, 0xFF, 0xFF, 0xFF };
406
407static const void* five_reference_pixels(SkColorType colorType) {
408    switch (colorType) {
409        case kUnknown_SkColorType:
410            return nullptr;
411        case kAlpha_8_SkColorType:
412            return alpha8;
413        case kRGB_565_SkColorType:
414            return rgb565;
415        case kARGB_4444_SkColorType:
416            return rgba4444;
417        case kRGBA_8888_SkColorType:
418            return rgba;
419        case kBGRA_8888_SkColorType:
420            return bgra;
421        case kGray_8_SkColorType:
422            return gray8;
423        case kRGBA_F16_SkColorType:
424            return f16;
425        default:
426            return nullptr;
427    }
428
429    SkASSERT(false);
430    return nullptr;
431}
432
433static void test_conversion(skiatest::Reporter* r, const SkImageInfo& dstInfo,
434                            const SkImageInfo& srcInfo) {
435    if (!SkImageInfoIsValid(srcInfo)) {
436        return;
437    }
438
439    const void* srcPixels = five_reference_pixels(srcInfo.colorType());
440    SkPixmap srcPixmap(srcInfo, srcPixels, srcInfo.minRowBytes());
441    sk_sp<SkImage> src = SkImage::MakeFromRaster(srcPixmap, nullptr, nullptr);
442    REPORTER_ASSERT(r, src);
443
444    // Enough space for 5 pixels when color type is F16, more than enough space in other cases.
445    uint64_t dstPixels[kNumPixels];
446    SkPixmap dstPixmap(dstInfo, dstPixels, dstInfo.minRowBytes());
447    bool success = src->readPixels(nullptr, dstPixmap, 0, 0);
448    REPORTER_ASSERT(r, success == SkImageInfoValidConversion(dstInfo, srcInfo));
449
450    if (success) {
451        if (kGray_8_SkColorType == srcInfo.colorType() &&
452            kGray_8_SkColorType != dstInfo.colorType()) {
453            // TODO: test (r,g,b) == (gray,gray,gray)?
454            return;
455        }
456
457        if (kGray_8_SkColorType == dstInfo.colorType() &&
458            kGray_8_SkColorType != srcInfo.colorType()) {
459            // TODO: test gray = luminance?
460            return;
461        }
462
463        if (kAlpha_8_SkColorType == srcInfo.colorType() &&
464            kAlpha_8_SkColorType != dstInfo.colorType()) {
465            // TODO: test output = black with this alpha?
466            return;
467        }
468
469        REPORTER_ASSERT(r, 0 == memcmp(dstPixels, five_reference_pixels(dstInfo.colorType()),
470                                       kNumPixels * SkColorTypeBytesPerPixel(dstInfo.colorType())));
471    }
472}
473
474DEF_TEST(ReadPixels_ValidConversion, reporter) {
475    const SkColorType kColorTypes[] = {
476            kUnknown_SkColorType,
477            kAlpha_8_SkColorType,
478            kRGB_565_SkColorType,
479            kARGB_4444_SkColorType,
480            kRGBA_8888_SkColorType,
481            kBGRA_8888_SkColorType,
482            kGray_8_SkColorType,
483            kRGBA_F16_SkColorType,
484    };
485
486    const SkAlphaType kAlphaTypes[] = {
487            kUnknown_SkAlphaType,
488            kOpaque_SkAlphaType,
489            kPremul_SkAlphaType,
490            kUnpremul_SkAlphaType,
491    };
492
493    const sk_sp<SkColorSpace> kColorSpaces[] = {
494            nullptr,
495            SkColorSpace::MakeSRGB(),
496    };
497
498    for (SkColorType dstCT : kColorTypes) {
499        for (SkAlphaType dstAT : kAlphaTypes) {
500            for (const sk_sp<SkColorSpace>& dstCS : kColorSpaces) {
501                for (SkColorType srcCT : kColorTypes) {
502                    for (SkAlphaType srcAT : kAlphaTypes) {
503                        for (const sk_sp<SkColorSpace>& srcCS : kColorSpaces) {
504                            test_conversion(reporter,
505                                            SkImageInfo::Make(kNumPixels, 1, dstCT, dstAT, dstCS),
506                                            SkImageInfo::Make(kNumPixels, 1, srcCT, srcAT, srcCS));
507                        }
508                    }
509                }
510            }
511        }
512    }
513}
514
515DEF_TEST(ReadPixels_InvalidRowBytes, reporter) {
516    auto srcII = SkImageInfo::Make({10, 10}, kRGBA_8888_SkColorType, kPremul_SkAlphaType);
517    auto surf = SkSurface::MakeRaster(srcII);
518    for (int ct = 0; ct < kLastEnum_SkColorType + 1; ++ct) {
519        auto colorType = static_cast<SkColorType>(ct);
520        size_t bpp = SkColorTypeBytesPerPixel(colorType);
521        if (bpp <= 1) {
522            continue;
523        }
524        auto dstII = srcII.makeColorType(colorType);
525        size_t badRowBytes = (surf->width() + 1)*bpp - 1;
526        auto storage = std::make_unique<char[]>(badRowBytes*surf->height());
527        REPORTER_ASSERT(reporter, !surf->readPixels(dstII, storage.get(), badRowBytes, 0, 0));
528    }
529}
530