Added CMYK support for ICC profiles.
Changed ICC parsing/SkGammas/SkColorLookUpTable to handle non-3-channel
inputs. Parsed CMYK A2B ICC profiles. Integrated this with SkJpegCodec
(the only file that supports CMYK) and SkColorSpaceXform_A2B to allow
parsing and color xforming of ICC CMYK images.
CQ_INCLUDE_TRYBOTS=skia.primary:Test-Ubuntu-GCC-GCE-CPU-AVX2-x86_64-Release-SKNX_NO_SIMD
Change-Id: I11e3d17180244281be3eb43fd608609925a7f71e
Reviewed-on: https://skia-review.googlesource.com/5444
Reviewed-by: Matt Sarett <msarett@google.com>
Commit-Queue: Matt Sarett <msarett@google.com>
diff --git a/src/core/SkColorSpace_A2B.h b/src/core/SkColorSpace_A2B.h
index 2fb7a83..b42de77 100644
--- a/src/core/SkColorSpace_A2B.h
+++ b/src/core/SkColorSpace_A2B.h
@@ -16,14 +16,15 @@
// is stored in an A2B0 ICC tag. This allows us to use alternative profile
// connection spaces (CIELAB instead of just CIEXYZ), use color-lookup-tables
// to do color space transformations not representable as TRC functions or
-// matrix operations, as well as have multiple TRC functions. The CLUT also has
-// the potential to allow conversion from input color spaces with a different
-// number of channels such as CMYK (4) or GRAY (1), but that is not supported yet.
+// matrix operations, as well as have multiple TRC functions. The CLUT also
+// allows conversion between non-3-channel input color spaces ie CMYK(4) to
+// a workable PCS (ie XYZ).
//
-// Currently AtoBType A2B0 tag types are supported. There are also lut8Type,
-// lut16Type and MPET (multi-processing-elements) A2B0 tags which allow you to
-// combine these 3 primitives (TRC, CLUT, matrix) in any order/quantitiy,
-// but support for that is not implemented.
+// AtoBType, lut8Type and lut16Type A2B0 tag types are supported. There are
+// also MPET (multi-processing-elements) A2B0 tags in the standard which allow
+// you to combine these 3 primitives (TRC, CLUT, matrix) in any order/quantity.
+// MPET tags are currently unsupported by the MakeICC parser, could be supported
+// here by the nature of the design.
class SkColorSpace_A2B : public SkColorSpace_Base {
public:
const SkMatrix44* toXYZD50() const override {
@@ -45,12 +46,12 @@
// as destination color spaces, so an inverse matrix is never wanted.
return nullptr;
}
-
+
bool onGammaCloseToSRGB() const override {
// There is no single gamma curve in an A2B0 profile
return false;
}
-
+
bool onGammaIsLinear() const override {
// There is no single gamma curve in an A2B0 profile
return false;
@@ -71,29 +72,37 @@
class Element {
public:
- explicit Element(SkGammaNamed gammaNamed)
+ Element(SkGammaNamed gammaNamed, int channelCount)
: fType(Type::kGammaNamed)
, fGammaNamed(gammaNamed)
, fMatrix(SkMatrix44::kUninitialized_Constructor)
+ , fInputChannels(channelCount)
+ , fOutputChannels(channelCount)
{}
explicit Element(sk_sp<SkGammas> gammas)
: fType(Type::kGammas)
, fGammas(std::move(gammas))
- , fMatrix(SkMatrix44::kUninitialized_Constructor)
+ , fMatrix(SkMatrix44::kUninitialized_Constructor)
+ , fInputChannels(fGammas->channels())
+ , fOutputChannels(fGammas->channels())
{}
explicit Element(sk_sp<SkColorLookUpTable> colorLUT)
: fType(Type::kCLUT)
, fCLUT(std::move(colorLUT))
, fMatrix(SkMatrix44::kUninitialized_Constructor)
+ , fInputChannels(fCLUT->inputChannels())
+ , fOutputChannels(fCLUT->outputChannels())
{}
explicit Element(const SkMatrix44& matrix)
: fType(Type::kMatrix)
, fMatrix(matrix)
+ , fInputChannels(3)
+ , fOutputChannels(3)
{}
-
+
enum class Type {
kGammaNamed,
kGammas,
@@ -123,15 +132,21 @@
return fMatrix;
}
+ int inputChannels() const { return fInputChannels; }
+
+ int outputChannels() const { return fOutputChannels; }
+
private:
Type fType;
SkGammaNamed fGammaNamed;
sk_sp<SkGammas> fGammas;
sk_sp<SkColorLookUpTable> fCLUT;
SkMatrix44 fMatrix;
+ int fInputChannels;
+ int fOutputChannels;
};
- const Element& element(size_t i) const { return fElements[i]; }
-
+ const Element& element(int i) const { return fElements[i]; }
+
int count() const { return (int)fElements.size(); }
// the intermediate profile connection space that this color space
@@ -140,16 +155,20 @@
kLAB, // CIELAB
kXYZ // CIEXYZ
};
-
+
PCS pcs() const { return fPCS; }
+ InputColorFormat inputColorFormat() const { return fInputColorFormat; }
+
private:
- SkColorSpace_A2B(PCS pcs, sk_sp<SkData> profileData, std::vector<Element> elements);
+ SkColorSpace_A2B(InputColorFormat inputColorFormat, std::vector<Element> elements, PCS pcs,
+ sk_sp<SkData> profileData);
- PCS fPCS;
+ InputColorFormat fInputColorFormat;
std::vector<Element> fElements;
+ PCS fPCS;
- friend class SkColorSpace;
+ friend class SkColorSpace_Base;
friend class ColorSpaceXformTest;
typedef SkColorSpace_Base INHERITED;
};