}

// Models for the standard color types.
var (
	RGBAModel    Model = ModelFunc(rgbaModel)
	RGBA64Model  Model = ModelFunc(rgba64Model)
	NRGBAModel   Model = ModelFunc(nrgbaModel)
	NRGBA64Model Model = ModelFunc(nrgba64Model)
	AlphaModel   Model = ModelFunc(alphaModel)
	Alpha16Model Model = ModelFunc(alpha16Model)
	GrayModel    Model = ModelFunc(grayModel)
	Gray16Model  Model = ModelFunc(gray16Model)
)

				t.Errorf("New%s: overflow: got ok, want !ok", tc.name)
			}
		}
	}
}

func Test16BitsPerColorChannel(t *testing.T) {
	testColorModel := []color.Model{
		color.RGBA64Model,
		color.NRGBA64Model,
		color.Alpha16Model,
		color.Gray16Model,
	}
	for _, cm := range testColorModel {
		c := cm.Convert(color.RGBA64{0x1234, 0x1234, 0x1234, 0x1234}) // Premultiplied alpha.
		r, _, _, _ := c.RGBA()

	case cbP1, cbP2, cbP4, cbP8:
		cm = d.palette
	case cbTCA8:
		cm = color.NRGBAModel
	case cbG16:
		cm = color.Gray16Model
	case cbGA16:
		cm = color.NRGBA64Model
	case cbTC16:
		cm = color.RGBA64Model
	case cbTCA16:
		cm = color.NRGBA64Model
	}
	return image.Config{
		ColorModel: cm,
		Width:      d.width,
		Height:     d.height,
	}, nil
}

func init() {

				cr[0][i+5] = uint8(b)
				i += 6
			}
		case cbTCA16:
			// Convert from image.Image (which is alpha-premultiplied) to PNG's non-alpha-premultiplied.
			for x := b.Min.X; x < b.Max.X; x++ {
				c := color.NRGBA64Model.Convert(m.At(x, y)).(color.NRGBA64)
				cr[0][i+0] = uint8(c.R >> 8)
				cr[0][i+1] = uint8(c.R)
				cr[0][i+2] = uint8(c.G >> 8)
				cr[0][i+3] = uint8(c.G)
				cr[0][i+4] = uint8(c.B >> 8)

		io.WriteString(w, s)
	} else {
		switch {
		case cm == color.RGBAModel, cm == color.RGBA64Model:
			io.WriteString(w, "    using color;\n")
		case cm == color.NRGBAModel, cm == color.NRGBA64Model:
			io.WriteString(w, "    using color alpha;\n")
		case cm == color.GrayModel, cm == color.Gray16Model:
			io.WriteString(w, "    using grayscale;\n")
		case cpm != nil:

	// Stride is the Pix stride (in bytes) between vertically adjacent pixels.
	Stride int
	// Rect is the image's bounds.
	Rect Rectangle
}

func (p *NRGBA64) ColorModel() color.Model { return color.NRGBA64Model }

func (p *NRGBA64) Bounds() Rectangle { return p.Rect }

func (p *NRGBA64) At(x, y int) color.Color {
	return p.NRGBA64At(x, y)
}

func (p *NRGBA64) RGBA64At(x, y int) color.RGBA64 {

		{"NRGBA.G", Field, 0},
		{"NRGBA.R", Field, 0},
		{"NRGBA64", Type, 0},
		{"NRGBA64.A", Field, 0},
		{"NRGBA64.B", Field, 0},
		{"NRGBA64.G", Field, 0},
		{"NRGBA64.R", Field, 0},
		{"NRGBA64Model", Var, 0},
		{"NRGBAModel", Var, 0},
		{"NYCbCrA", Type, 6},
		{"NYCbCrA.A", Field, 6},
		{"NYCbCrA.YCbCr", Field, 6},
		{"NYCbCrAModel", Var, 6},
		{"Opaque", Var, 0},
		{"Palette", Type, 0},

pkg image/color, var Alpha16Model Model
pkg image/color, var AlphaModel Model
pkg image/color, var Black Gray16
pkg image/color, var Gray16Model Model
pkg image/color, var GrayModel Model
pkg image/color, var NRGBA64Model Model
pkg image/color, var NRGBAModel Model
pkg image/color, var Opaque Alpha16
pkg image/color, var RGBA64Model Model
pkg image/color, var RGBAModel Model
pkg image/color, var Transparent Alpha16