| /* |
| * Copyright 2015 Google Inc. |
| * |
| * Use of this source code is governed by a BSD-style license that can be |
| * found in the LICENSE file. |
| */ |
| |
| #include "SkAndroidCodec.h" |
| #include "SkCodec.h" |
| #include "SkCodecPriv.h" |
| #include "SkRawAdapterCodec.h" |
| #include "SkSampledCodec.h" |
| #include "SkWebpAdapterCodec.h" |
| |
| static bool is_valid_sample_size(int sampleSize) { |
| // FIXME: As Leon has mentioned elsewhere, surely there is also a maximum sampleSize? |
| return sampleSize > 0; |
| } |
| |
| /** |
| * Loads the gamut as a set of three points (triangle). |
| */ |
| static void load_gamut(SkPoint rgb[], const SkMatrix44& xyz) { |
| // rx = rX / (rX + rY + rZ) |
| // ry = rY / (rX + rY + rZ) |
| // gx, gy, bx, and gy are calulcated similarly. |
| float rSum = xyz.get(0, 0) + xyz.get(1, 0) + xyz.get(2, 0); |
| float gSum = xyz.get(0, 1) + xyz.get(1, 1) + xyz.get(2, 1); |
| float bSum = xyz.get(0, 2) + xyz.get(1, 2) + xyz.get(2, 2); |
| rgb[0].fX = xyz.get(0, 0) / rSum; |
| rgb[0].fY = xyz.get(1, 0) / rSum; |
| rgb[1].fX = xyz.get(0, 1) / gSum; |
| rgb[1].fY = xyz.get(1, 1) / gSum; |
| rgb[2].fX = xyz.get(0, 2) / bSum; |
| rgb[2].fY = xyz.get(1, 2) / bSum; |
| } |
| |
| /** |
| * Calculates the area of the triangular gamut. |
| */ |
| static float calculate_area(SkPoint abc[]) { |
| SkPoint a = abc[0]; |
| SkPoint b = abc[1]; |
| SkPoint c = abc[2]; |
| return 0.5f * SkTAbs(a.fX*b.fY + b.fX*c.fY - a.fX*c.fY - c.fX*b.fY - b.fX*a.fY); |
| } |
| |
| static const float kSRGB_D50_GamutArea = 0.084f; |
| |
| static bool is_wide_gamut(const SkColorSpace* colorSpace) { |
| // Determine if the source image has a gamut that is wider than sRGB. If so, we |
| // will use P3 as the output color space to avoid clipping the gamut. |
| const SkMatrix44* toXYZD50 = as_CSB(colorSpace)->toXYZD50(); |
| if (toXYZD50) { |
| SkPoint rgb[3]; |
| load_gamut(rgb, *toXYZD50); |
| return calculate_area(rgb) > kSRGB_D50_GamutArea; |
| } |
| |
| return false; |
| } |
| |
| SkAndroidCodec::SkAndroidCodec(SkCodec* codec) |
| : fInfo(codec->getInfo()) |
| , fCodec(codec) |
| {} |
| |
| SkAndroidCodec* SkAndroidCodec::NewFromStream(SkStream* stream, SkPngChunkReader* chunkReader) { |
| std::unique_ptr<SkCodec> codec(SkCodec::NewFromStream(stream, nullptr, chunkReader)); |
| if (nullptr == codec) { |
| return nullptr; |
| } |
| |
| switch ((SkEncodedImageFormat)codec->getEncodedFormat()) { |
| #ifdef SK_HAS_PNG_LIBRARY |
| case SkEncodedImageFormat::kPNG: |
| case SkEncodedImageFormat::kICO: |
| #endif |
| #ifdef SK_HAS_JPEG_LIBRARY |
| case SkEncodedImageFormat::kJPEG: |
| #endif |
| case SkEncodedImageFormat::kGIF: |
| case SkEncodedImageFormat::kBMP: |
| case SkEncodedImageFormat::kWBMP: |
| return new SkSampledCodec(codec.release()); |
| #ifdef SK_HAS_WEBP_LIBRARY |
| case SkEncodedImageFormat::kWEBP: |
| return new SkWebpAdapterCodec((SkWebpCodec*) codec.release()); |
| #endif |
| #ifdef SK_CODEC_DECODES_RAW |
| case SkEncodedImageFormat::kDNG: |
| return new SkRawAdapterCodec((SkRawCodec*)codec.release()); |
| #endif |
| default: |
| return nullptr; |
| } |
| } |
| |
| SkAndroidCodec* SkAndroidCodec::NewFromData(sk_sp<SkData> data, SkPngChunkReader* chunkReader) { |
| if (!data) { |
| return nullptr; |
| } |
| |
| return NewFromStream(new SkMemoryStream(data), chunkReader); |
| } |
| |
| SkColorType SkAndroidCodec::computeOutputColorType(SkColorType requestedColorType) { |
| bool highPrecision = fCodec->getEncodedInfo().bitsPerComponent() > 8; |
| switch (requestedColorType) { |
| case kARGB_4444_SkColorType: |
| return kN32_SkColorType; |
| case kN32_SkColorType: |
| break; |
| case kAlpha_8_SkColorType: |
| // Fall through to kGray_8. Before kGray_8_SkColorType existed, |
| // we allowed clients to request kAlpha_8 when they wanted a |
| // grayscale decode. |
| case kGray_8_SkColorType: |
| if (kGray_8_SkColorType == this->getInfo().colorType()) { |
| return kGray_8_SkColorType; |
| } |
| break; |
| case kRGB_565_SkColorType: |
| if (kOpaque_SkAlphaType == this->getInfo().alphaType()) { |
| return kRGB_565_SkColorType; |
| } |
| break; |
| case kRGBA_F16_SkColorType: |
| return kRGBA_F16_SkColorType; |
| default: |
| break; |
| } |
| |
| // F16 is the Android default for high precision images. |
| return highPrecision ? kRGBA_F16_SkColorType : kN32_SkColorType; |
| } |
| |
| SkAlphaType SkAndroidCodec::computeOutputAlphaType(bool requestedUnpremul) { |
| if (kOpaque_SkAlphaType == this->getInfo().alphaType()) { |
| return kOpaque_SkAlphaType; |
| } |
| return requestedUnpremul ? kUnpremul_SkAlphaType : kPremul_SkAlphaType; |
| } |
| |
| sk_sp<SkColorSpace> SkAndroidCodec::computeOutputColorSpace(SkColorType outputColorType, |
| sk_sp<SkColorSpace> prefColorSpace) { |
| switch (outputColorType) { |
| case kRGBA_8888_SkColorType: |
| case kBGRA_8888_SkColorType: { |
| // If |prefColorSpace| is supported, choose it. |
| SkColorSpaceTransferFn fn; |
| if (prefColorSpace && prefColorSpace->isNumericalTransferFn(&fn)) { |
| return prefColorSpace; |
| } |
| |
| SkColorSpace* encodedSpace = fCodec->getInfo().colorSpace(); |
| if (encodedSpace->isNumericalTransferFn(&fn)) { |
| // Leave the pixels in the encoded color space. Color space conversion |
| // will be handled after decode time. |
| return sk_ref_sp(encodedSpace); |
| } |
| |
| if (is_wide_gamut(encodedSpace)) { |
| return SkColorSpace::MakeRGB(SkColorSpace::kSRGB_RenderTargetGamma, |
| SkColorSpace::kDCIP3_D65_Gamut); |
| } |
| |
| return SkColorSpace::MakeSRGB(); |
| } |
| case kRGBA_F16_SkColorType: |
| // Note that |prefColorSpace| is ignored, F16 is always linear sRGB. |
| return SkColorSpace::MakeSRGBLinear(); |
| case kRGB_565_SkColorType: |
| // Note that |prefColorSpace| is ignored, 565 is always sRGB. |
| return SkColorSpace::MakeSRGB(); |
| default: |
| // Color correction not supported for kGray. |
| return nullptr; |
| } |
| } |
| |
| SkISize SkAndroidCodec::getSampledDimensions(int sampleSize) const { |
| if (!is_valid_sample_size(sampleSize)) { |
| return {0, 0}; |
| } |
| |
| // Fast path for when we are not scaling. |
| if (1 == sampleSize) { |
| return fInfo.dimensions(); |
| } |
| |
| return this->onGetSampledDimensions(sampleSize); |
| } |
| |
| bool SkAndroidCodec::getSupportedSubset(SkIRect* desiredSubset) const { |
| if (!desiredSubset || !is_valid_subset(*desiredSubset, fInfo.dimensions())) { |
| return false; |
| } |
| |
| return this->onGetSupportedSubset(desiredSubset); |
| } |
| |
| SkISize SkAndroidCodec::getSampledSubsetDimensions(int sampleSize, const SkIRect& subset) const { |
| if (!is_valid_sample_size(sampleSize)) { |
| return {0, 0}; |
| } |
| |
| // We require that the input subset is a subset that is supported by SkAndroidCodec. |
| // We test this by calling getSupportedSubset() and verifying that no modifications |
| // are made to the subset. |
| SkIRect copySubset = subset; |
| if (!this->getSupportedSubset(©Subset) || copySubset != subset) { |
| return {0, 0}; |
| } |
| |
| // If the subset is the entire image, for consistency, use getSampledDimensions(). |
| if (fInfo.dimensions() == subset.size()) { |
| return this->getSampledDimensions(sampleSize); |
| } |
| |
| // This should perhaps call a virtual function, but currently both of our subclasses |
| // want the same implementation. |
| return {get_scaled_dimension(subset.width(), sampleSize), |
| get_scaled_dimension(subset.height(), sampleSize)}; |
| } |
| |
| SkCodec::Result SkAndroidCodec::getAndroidPixels(const SkImageInfo& info, void* pixels, |
| size_t rowBytes, const AndroidOptions* options) { |
| if (!pixels) { |
| return SkCodec::kInvalidParameters; |
| } |
| if (rowBytes < info.minRowBytes()) { |
| return SkCodec::kInvalidParameters; |
| } |
| |
| AndroidOptions defaultOptions; |
| if (!options) { |
| options = &defaultOptions; |
| } else if (options->fSubset) { |
| if (!is_valid_subset(*options->fSubset, fInfo.dimensions())) { |
| return SkCodec::kInvalidParameters; |
| } |
| |
| if (SkIRect::MakeSize(fInfo.dimensions()) == *options->fSubset) { |
| // The caller wants the whole thing, rather than a subset. Modify |
| // the AndroidOptions passed to onGetAndroidPixels to not specify |
| // a subset. |
| defaultOptions = *options; |
| defaultOptions.fSubset = nullptr; |
| options = &defaultOptions; |
| } |
| } |
| |
| return this->onGetAndroidPixels(info, pixels, rowBytes, *options); |
| } |
| |
| SkCodec::Result SkAndroidCodec::getAndroidPixels(const SkImageInfo& info, void* pixels, |
| size_t rowBytes) { |
| return this->getAndroidPixels(info, pixels, rowBytes, nullptr); |
| } |