C++ SkBitmap::colorType方法代码示例

void copy_to_g8(SkBitmap* dst, const SkBitmap& src) {
    SkASSERT(kBGRA_8888_SkColorType == src.colorType() ||
             kRGBA_8888_SkColorType == src.colorType());

    SkImageInfo grayInfo = src.info().makeColorType(kGray_8_SkColorType);
    dst->allocPixels(grayInfo);
    uint8_t* dst8 = (uint8_t*)dst->getPixels();
    const uint32_t* src32 = (const uint32_t*)src.getPixels();

    const int w = src.width();
    const int h = src.height();
    const bool isBGRA = (kBGRA_8888_SkColorType == src.colorType());
    for (int y = 0; y < h; ++y) {
        if (isBGRA) {
            // BGRA
            for (int x = 0; x < w; ++x) {
                uint32_t s = src32[x];
                dst8[x] = SkComputeLuminance((s >> 16) & 0xFF, (s >> 8) & 0xFF, s & 0xFF);
            }
        } else {
            // RGBA
            for (int x = 0; x < w; ++x) {
                uint32_t s = src32[x];
                dst8[x] = SkComputeLuminance(s & 0xFF, (s >> 8) & 0xFF, (s >> 16) & 0xFF);
            }
        }
        src32 = (const uint32_t*)((const char*)src32 + src.rowBytes());
        dst8 += dst->rowBytes();
    }

// A contructor-type function that returns NULL on failure.  This
// prevents the returned SkImageGenerator from ever being in a bad
// state.  Called by both Create() functions
SkImageGenerator* CreateDecodingImageGenerator(
        SkData* data,
        SkStreamRewindable* stream,
        const SkDecodingImageGenerator::Options& opts) {
    SkASSERT(stream);
    SkAutoTUnref<SkStreamRewindable> autoStream(stream);  // always unref this.
    if (opts.fUseRequestedColorType &&
        (kIndex_8_SkColorType == opts.fRequestedColorType)) {
        // We do not support indexed color with SkImageGenerators,
        return NULL;
    }
    SkAssertResult(autoStream->rewind());
    SkAutoTDelete<SkImageDecoder> decoder(SkImageDecoder::Factory(autoStream));
    if (NULL == decoder.get()) {
        return NULL;
    }
    SkBitmap bitmap;
    decoder->setSampleSize(opts.fSampleSize);
    decoder->setRequireUnpremultipliedColors(opts.fRequireUnpremul);
    if (!decoder->decode(stream, &bitmap,
                         SkImageDecoder::kDecodeBounds_Mode)) {
        return NULL;
    }
    if (bitmap.config() == SkBitmap::kNo_Config) {
        return NULL;
    }

    SkImageInfo info = bitmap.info();

    if (!opts.fUseRequestedColorType) {
        // Use default
        if (kIndex_8_SkColorType == bitmap.colorType()) {
            // We don't support kIndex8 because we don't support
            // colortables in this workflow.
            info.fColorType = kN32_SkColorType;
        }
    } else {
        if (!bitmap.canCopyTo(opts.fRequestedColorType)) {
            SkASSERT(bitmap.colorType() != opts.fRequestedColorType);
            return NULL;  // Can not translate to needed config.
        }
        info.fColorType = opts.fRequestedColorType;
    }

    if (opts.fRequireUnpremul && info.fAlphaType != kOpaque_SkAlphaType) {
        info.fAlphaType = kUnpremul_SkAlphaType;
    }
    return SkNEW_ARGS(DecodingImageGenerator,
                      (data, autoStream.detach(), info,
                       opts.fSampleSize, opts.fDitherImage));
}

    void force_all_opaque(const SkBitmap& bitmap) {
        SkASSERT(NULL == bitmap.getTexture());
        SkASSERT(kN32_SkColorType == bitmap.colorType());
        if (bitmap.getTexture() || kN32_SkColorType == bitmap.colorType()) {
            return;
        }

        SkAutoLockPixels lock(bitmap);
        for (int y = 0; y < bitmap.height(); y++) {
            for (int x = 0; x < bitmap.width(); x++) {
                *bitmap.getAddr32(x, y) |= (SK_A32_MASK << SK_A32_SHIFT);
            }
        }
    }

static void emit_image_xobject(SkWStream* stream,
                               const SkImage* image,
                               bool alpha,
                               const sk_sp<SkPDFObject>& smask,
                               const SkPDFObjNumMap& objNumMap,
                               const SkPDFSubstituteMap& substitutes) {
    SkBitmap bitmap;
    image_get_ro_pixels(image, &bitmap);      // TODO(halcanary): test
    SkAutoLockPixels autoLockPixels(bitmap);  // with malformed images.

    // Write to a temporary buffer to get the compressed length.
    SkDynamicMemoryWStream buffer;
    SkDeflateWStream deflateWStream(&buffer);
    if (alpha) {
        bitmap_alpha_to_a8(bitmap, &deflateWStream);
    } else {
        bitmap_to_pdf_pixels(bitmap, &deflateWStream);
    }
    deflateWStream.finalize();  // call before detachAsStream().
    std::unique_ptr<SkStreamAsset> asset(buffer.detachAsStream());

    SkPDFDict pdfDict("XObject");
    pdfDict.insertName("Subtype", "Image");
    pdfDict.insertInt("Width", bitmap.width());
    pdfDict.insertInt("Height", bitmap.height());
    if (alpha) {
        pdfDict.insertName("ColorSpace", "DeviceGray");
    } else if (bitmap.colorType() == kIndex_8_SkColorType) {
        SkASSERT(1 == pdf_color_component_count(bitmap.colorType()));
        pdfDict.insertObject("ColorSpace",
                             make_indexed_color_space(bitmap.getColorTable(),
                                                      bitmap.alphaType()));
    } else if (1 == pdf_color_component_count(bitmap.colorType())) {
        pdfDict.insertName("ColorSpace", "DeviceGray");
    } else {
        pdfDict.insertName("ColorSpace", "DeviceRGB");
    }
    if (smask) {
        pdfDict.insertObjRef("SMask", smask);
    }
    pdfDict.insertInt("BitsPerComponent", 8);
    pdfDict.insertName("Filter", "FlateDecode");
    pdfDict.insertInt("Length", asset->getLength());
    pdfDict.emitObject(stream, objNumMap, substitutes);

    pdf_stream_begin(stream);
    stream->writeStream(asset.get(), asset->getLength());
    pdf_stream_end(stream);
}

bool SkBitmapDevice::onReadPixels(const SkBitmap& bitmap,
                                  int x, int y,
                                  SkCanvas::Config8888 config8888) {
    SkASSERT(SkBitmap::kARGB_8888_Config == bitmap.config());
    SkASSERT(!bitmap.isNull());
    SkASSERT(SkIRect::MakeWH(this->width(), this->height()).contains(SkIRect::MakeXYWH(x, y,
                                                                          bitmap.width(),
                                                                          bitmap.height())));

    SkIRect srcRect = SkIRect::MakeXYWH(x, y, bitmap.width(), bitmap.height());
    const SkBitmap& src = this->accessBitmap(false);

    SkBitmap subset;
    if (!src.extractSubset(&subset, srcRect)) {
        return false;
    }
    if (kPMColor_SkColorType != subset.colorType()) {
        // It'd be preferable to do this directly to bitmap.
        subset.copyTo(&subset, kPMColor_SkColorType);
    }
    SkAutoLockPixels alp(bitmap);
    uint32_t* bmpPixels = reinterpret_cast<uint32_t*>(bitmap.getPixels());
    SkCopyBitmapToConfig8888(bmpPixels, bitmap.rowBytes(), config8888, subset);
    return true;
}

// returns true and set color if the bitmap can be drawn as a single color
// (for efficiency)
static bool can_use_color_shader(const SkBitmap& bm, SkColor* color) {
#ifdef SK_BUILD_FOR_ANDROID_FRAMEWORK
    // HWUI does not support color shaders (see b/22390304)
    return false;
#endif

    if (1 != bm.width() || 1 != bm.height()) {
        return false;
    }

    SkAutoLockPixels alp(bm);
    if (!bm.readyToDraw()) {
        return false;
    }

    switch (bm.colorType()) {
        case kN32_SkColorType:
            *color = SkUnPreMultiply::PMColorToColor(*bm.getAddr32(0, 0));
            return true;
        case kRGB_565_SkColorType:
            *color = SkPixel16ToColor(*bm.getAddr16(0, 0));
            return true;
        case kIndex_8_SkColorType:
            *color = SkUnPreMultiply::PMColorToColor(bm.getIndex8Color(0, 0));
            return true;
        default: // just skip the other configs for now
            break;
    }
    return false;
}

/* It is necessary to average the color component of transparent
   pixels with their surrounding neighbors since the PDF renderer may
   separately re-sample the alpha and color channels when the image is
   not displayed at its native resolution. Since an alpha of zero
   gives no information about the color component, the pathological
   case is a white image with sharp transparency bounds - the color
   channel goes to black, and the should-be-transparent pixels are
   rendered as grey because of the separate soft mask and color
   resizing. e.g.: gm/bitmappremul.cpp */
static void get_neighbor_avg_color(const SkBitmap& bm,
                                   int xOrig,
                                   int yOrig,
                                   uint8_t rgb[3]) {
    SkASSERT(kN32_SkColorType == bm.colorType());
    unsigned a = 0, r = 0, g = 0, b = 0;
    // Clamp the range to the edge of the bitmap.
    int ymin = SkTMax(0, yOrig - 1);
    int ymax = SkTMin(yOrig + 1, bm.height() - 1);
    int xmin = SkTMax(0, xOrig - 1);
    int xmax = SkTMin(xOrig + 1, bm.width() - 1);
    for (int y = ymin; y <= ymax; ++y) {
        SkPMColor* scanline = bm.getAddr32(0, y);
        for (int x = xmin; x <= xmax; ++x) {
            SkPMColor pmColor = scanline[x];
            a += SkGetPackedA32(pmColor);
            r += SkGetPackedR32(pmColor);
            g += SkGetPackedG32(pmColor);
            b += SkGetPackedB32(pmColor);
        }
    }
    if (a > 0) {
        rgb[0] = SkToU8(255 * r / a);
        rgb[1] = SkToU8(255 * g / a);
        rgb[2] = SkToU8(255 * b / a);
    } else {
        rgb[0] = rgb[1] = rgb[2] = 0;
    }
}

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");
    }
}

// returns true and set color if the bitmap can be drawn as a single color
// (for efficiency)
static bool canUseColorShader(const SkBitmap& bm, SkColor* color) {
    if (1 != bm.width() || 1 != bm.height()) {
        return false;
    }

    SkAutoLockPixels alp(bm);
    if (!bm.readyToDraw()) {
        return false;
    }

    switch (bm.colorType()) {
        case kN32_SkColorType:
            *color = SkUnPreMultiply::PMColorToColor(*bm.getAddr32(0, 0));
            return true;
        case kRGB_565_SkColorType:
            *color = SkPixel16ToColor(*bm.getAddr16(0, 0));
            return true;
        case kIndex_8_SkColorType:
            *color = SkUnPreMultiply::PMColorToColor(bm.getIndex8Color(0, 0));
            return true;
        default: // just skip the other configs for now
            break;
    }
    return false;
}

static SkBitmap deepSkBitmapCopy(const SkBitmap& bitmap)
{
    SkBitmap tmp;
    if (!bitmap.deepCopyTo(&tmp))
        bitmap.copyTo(&tmp, bitmap.colorType());

    return tmp;
}

void draw(SkCanvas* canvas) {
    const char* colors[] = {"Unknown", "Alpha_8", "RGB_565", "ARGB_4444", "RGBA_8888", "RGB_888x",
                            "BGRA_8888", "RGBA_1010102", "RGB_101010x", "Gray_8", "RGBA_F16Norm",
                            "RGBA_F16"};
    SkBitmap bitmap;
    bitmap.setInfo(SkImageInfo::MakeA8(16, 32));
    SkDebugf("color type: k" "%s" "_SkColorType\n", colors[bitmap.colorType()]);
}

/*
 *  High quality is implemented by performing up-right scale-only filtering and then
 *  using bilerp for any remaining transformations.
 */
bool SkDefaultBitmapControllerState::processHQRequest(const SkBitmap& origBitmap) {
    if (fQuality != kHigh_SkFilterQuality) {
        return false;
    }
    
    // Our default return state is to downgrade the request to Medium, w/ or w/o setting fBitmap
    // to a valid bitmap. If we succeed, we will set this to Low instead.
    fQuality = kMedium_SkFilterQuality;
    
    if (kN32_SkColorType != origBitmap.colorType() || !cache_size_okay(origBitmap, fInvMatrix) ||
        fInvMatrix.hasPerspective())
    {
        return false; // can't handle the reqeust
    }
    
    SkScalar invScaleX = fInvMatrix.getScaleX();
    SkScalar invScaleY = fInvMatrix.getScaleY();
    if (fInvMatrix.getType() & SkMatrix::kAffine_Mask) {
        SkSize scale;
        if (!fInvMatrix.decomposeScale(&scale)) {
            return false;
        }
        invScaleX = scale.width();
        invScaleY = scale.height();
    }
    if (SkScalarNearlyEqual(invScaleX, 1) && SkScalarNearlyEqual(invScaleY, 1)) {
        return false; // no need for HQ
    }
    
    SkScalar trueDestWidth  = origBitmap.width() / invScaleX;
    SkScalar trueDestHeight = origBitmap.height() / invScaleY;
    SkScalar roundedDestWidth = SkScalarRoundToScalar(trueDestWidth);
    SkScalar roundedDestHeight = SkScalarRoundToScalar(trueDestHeight);
    
    if (!SkBitmapCache::Find(origBitmap, roundedDestWidth, roundedDestHeight, &fResultBitmap)) {
        SkAutoPixmapUnlock src;
        if (!origBitmap.requestLock(&src)) {
            return false;
        }
        if (!SkBitmapScaler::Resize(&fResultBitmap, src.pixmap(), SkBitmapScaler::RESIZE_BEST,
                                    roundedDestWidth, roundedDestHeight,
                                    SkResourceCache::GetAllocator())) {
            return false; // we failed to create fScaledBitmap
        }
        
        SkASSERT(fResultBitmap.getPixels());
        fResultBitmap.setImmutable();
        SkBitmapCache::Add(origBitmap, roundedDestWidth, roundedDestHeight, fResultBitmap);
    }
    
    SkASSERT(fResultBitmap.getPixels());
    
    fInvMatrix.postScale(roundedDestWidth / origBitmap.width(),
                         roundedDestHeight / origBitmap.height());
    fQuality = kLow_SkFilterQuality;
    return true;
}

/**
 * First, make sure that writing an 8-bit RGBA KTX file and then
 * reading it produces the same bitmap.
 */
DEF_TEST(KtxReadWrite, reporter) {

    // Random number generator with explicit seed for reproducibility
    SkRandom rand(0x1005cbad);

    SkBitmap bm8888;
    bool pixelsAllocated = bm8888.allocN32Pixels(128, 128);
    REPORTER_ASSERT(reporter, pixelsAllocated);

    uint8_t *pixels = reinterpret_cast<uint8_t*>(bm8888.getPixels());
    REPORTER_ASSERT(reporter, NULL != pixels);

    if (NULL == pixels) {
        return;
    }
    
    uint8_t *row = pixels;
    for (int y = 0; y < bm8888.height(); ++y) {        
        for (int x = 0; x < bm8888.width(); ++x) {
            uint8_t a = rand.nextRangeU(0, 255);
            uint8_t r = rand.nextRangeU(0, 255);
            uint8_t g = rand.nextRangeU(0, 255);
            uint8_t b = rand.nextRangeU(0, 255);

            SkPMColor &pixel = *(reinterpret_cast<SkPMColor*>(row + x*sizeof(SkPMColor)));
            pixel = SkPreMultiplyARGB(a, r, g, b);
        }
        row += bm8888.rowBytes();
    }
    REPORTER_ASSERT(reporter, !(bm8888.empty()));

    SkAutoDataUnref encodedData(SkImageEncoder::EncodeData(bm8888, SkImageEncoder::kKTX_Type, 0));
    REPORTER_ASSERT(reporter, NULL != encodedData);

    SkAutoTUnref<SkMemoryStream> stream(SkNEW_ARGS(SkMemoryStream, (encodedData)));
    REPORTER_ASSERT(reporter, NULL != stream);

    SkBitmap decodedBitmap;
    bool imageDecodeSuccess = SkImageDecoder::DecodeStream(stream, &decodedBitmap);
    REPORTER_ASSERT(reporter, imageDecodeSuccess);

    REPORTER_ASSERT(reporter, decodedBitmap.colorType() == bm8888.colorType());
    REPORTER_ASSERT(reporter, decodedBitmap.alphaType() == bm8888.alphaType());
    REPORTER_ASSERT(reporter, decodedBitmap.width() == bm8888.width());
    REPORTER_ASSERT(reporter, decodedBitmap.height() == bm8888.height());
    REPORTER_ASSERT(reporter, !(decodedBitmap.empty()));

    uint8_t *decodedPixels = reinterpret_cast<uint8_t*>(decodedBitmap.getPixels());
    REPORTER_ASSERT(reporter, NULL != decodedPixels);
    REPORTER_ASSERT(reporter, decodedBitmap.getSize() == bm8888.getSize());

    if (NULL == decodedPixels) {
        return;
    }

    REPORTER_ASSERT(reporter, memcmp(decodedPixels, pixels, decodedBitmap.getSize()) == 0);
}

static void draw(SkCanvas* canvas,
                 const SkPaint& p,
                 const SkBitmap& src,
                 SkColorType colorType,
                 const char text[]) {
    SkASSERT(src.colorType() == colorType);
    canvas->drawBitmap(src, 0.0f, 0.0f);
    canvas->drawText(text, strlen(text), 0.0f, 12.0f, p);
}

bool SkMatrixConvolutionImageFilter::onFilterImage(Proxy* proxy,
                                                   const SkBitmap& source,
                                                   const Context& ctx,
                                                   SkBitmap* result,
                                                   SkIPoint* offset) const {
    SkBitmap src = source;
    SkIPoint srcOffset = SkIPoint::Make(0, 0);
    if (!this->filterInput(0, proxy, source, ctx, &src, &srcOffset)) {
        return false;
    }

    if (src.colorType() != kN32_SkColorType) {
        return false;
    }

    SkIRect bounds;
    if (!this->applyCropRect(ctx, proxy, src, &srcOffset, &bounds, &src)) {
        return false;
    }

    if (!fConvolveAlpha && !src.isOpaque()) {
        src = unpremultiplyBitmap(proxy, src);
    }

    SkAutoLockPixels alp(src);
    if (!src.getPixels()) {
        return false;
    }

    SkAutoTUnref<SkBaseDevice> device(proxy->createDevice(bounds.width(), bounds.height()));
    if (!device) {
        return false;
    }
    *result = device->accessBitmap(false);
    SkAutoLockPixels alp_result(*result);

    offset->fX = bounds.fLeft;
    offset->fY = bounds.fTop;
    bounds.offset(-srcOffset);
    SkIRect interior = SkIRect::MakeXYWH(bounds.left() + fKernelOffset.fX,
                                         bounds.top() + fKernelOffset.fY,
                                         bounds.width() - fKernelSize.fWidth + 1,
                                         bounds.height() - fKernelSize.fHeight + 1);
    SkIRect top = SkIRect::MakeLTRB(bounds.left(), bounds.top(), bounds.right(), interior.top());
    SkIRect bottom = SkIRect::MakeLTRB(bounds.left(), interior.bottom(),
                                       bounds.right(), bounds.bottom());
    SkIRect left = SkIRect::MakeLTRB(bounds.left(), interior.top(),
                                     interior.left(), interior.bottom());
    SkIRect right = SkIRect::MakeLTRB(interior.right(), interior.top(),
                                      bounds.right(), interior.bottom());
    filterBorderPixels(src, result, top, bounds);
    filterBorderPixels(src, result, left, bounds);
    filterInteriorPixels(src, result, interior, bounds);
    filterBorderPixels(src, result, right, bounds);
    filterBorderPixels(src, result, bottom, bounds);
    return true;
}