video-001.cmyk.jpeg...

video-001.cmyk.png...

pkg image, func NewCMYK(Rectangle) *CMYK
pkg image, method (*CMYK) At(int, int) color.Color
pkg image, method (*CMYK) Bounds() Rectangle
pkg image, method (*CMYK) CMYKAt(int, int) color.CMYK
pkg image, method (*CMYK) ColorModel() color.Model
pkg image, method (*CMYK) Opaque() bool
pkg image, method (*CMYK) PixOffset(int, int) int
pkg image, method (*CMYK) Set(int, int, color.Color)

}

// CMYKToRGB converts a [CMYK] quadruple to an RGB triple.
func CMYKToRGB(c, m, y, k uint8) (uint8, uint8, uint8) {
	w := 0xffff - uint32(k)*0x101
	r := (0xffff - uint32(c)*0x101) * w / 0xffff
	g := (0xffff - uint32(m)*0x101) * w / 0xffff
	b := (0xffff - uint32(y)*0x101) * w / 0xffff
	return uint8(r >> 8), uint8(g >> 8), uint8(b >> 8)
}

// CMYK represents a fully opaque CMYK color, having 8 bits for each of cyan,

}

func (p *CMYK) CMYKAt(x, y int) color.CMYK {
	if !(Point{x, y}.In(p.Rect)) {
		return color.CMYK{}
	}
	i := p.PixOffset(x, y)
	s := p.Pix[i : i+4 : i+4] // Small cap improves performance, see https://golang.org/issue/27857
	return color.CMYK{s[0], s[1], s[2], s[3]}
}

// PixOffset returns the index of the first element of Pix that corresponds to
// the pixel at (x, y).
func (p *CMYK) PixOffset(x, y int) int {

	{"testdata/video-001.png", "testdata/video-001.progressive.jpeg", 8 << 8},
	{"testdata/video-001.221212.png", "testdata/video-001.221212.jpeg", 8 << 8},
	{"testdata/video-001.cmyk.png", "testdata/video-001.cmyk.jpeg", 8 << 8},
	{"testdata/video-001.rgb.png", "testdata/video-001.rgb.jpeg", 8 << 8},
	{"testdata/video-001.progressive.truncated.png", "testdata/video-001.progressive.truncated.jpeg", 8 << 8},
	// Grayscale images.

		}
		return d.img3, nil
	}
	return nil, FormatError("missing SOS marker")
}

// applyBlack combines d.img3 and d.blackPix into a CMYK image. The formula
// used depends on whether the JPEG image is stored as CMYK or YCbCrK,
// indicated by the APP14 (Adobe) metadata.
//
// Adobe CMYK JPEG images are inverted, where 255 means no ink instead of full
// ink, so we apply "v = 255 - v" at various points. Note that a double

var unkeyedLiteral = map[string]bool{
	// These image and image/color struct types are frozen. We will never add fields to them.
	"image/color.Alpha16": true,
	"image/color.Alpha":   true,
	"image/color.CMYK":    true,
	"image/color.Gray16":  true,
	"image/color.Gray":    true,
	"image/color.NRGBA64": true,
	"image/color.NRGBA":   true,
	"image/color.NYCbCrA": true,
	"image/color.RGBA64":  true,

							c, m, y, k, r1, g1, b1, r2, g2, b2)
					}
				}
			}
		}
	}
}

// TestCMYKGray tests that CMYK colors are a superset of Gray colors.
func TestCMYKGray(t *testing.T) {
	for i := 0; i < 256; i++ {
		if err := eq(CMYK{0x00, 0x00, 0x00, uint8(255 - i)}, Gray{uint8(i)}); err != nil {
			t.Errorf("i=0x%02x:\n%v", i, err)
		}
	}
}

func TestPalette(t *testing.T) {

	case color.CMYKModel:
		src1 := image.NewCMYK(image.Rect(0, 0, srcw, srch))
		for y := 0; y < srch; y++ {
			for x := 0; x < srcw; x++ {
				src1.SetCMYK(x, y, color.CMYK{
					uint8(13 * x % 0x100),
					uint8(11 * y % 0x100),
					uint8((11*x + 13*y) % 0x100),
					uint8((31*x + 37*y) % 0x100),
				})
			}
		}
		src = src1
	case color.GrayModel: