adjust tests

ajust_test.go

@@ -0,0 +1,504 @@
+package imaging
+
+import (
+	"image"
+	"testing"
+)
+
+func TestGrayscale(t *testing.T) {
+	td := []struct {
+		desc string
+		src  image.Image
+		want *image.NRGBA
+	}{
+		{
+			"Grayscale 3x3",
+			&image.NRGBA{
+				Rect:   image.Rect(-1, -1, 2, 2),
+				Stride: 3 * 4,
+				Pix: []uint8{
+					0xcc, 0x00, 0x00, 0x01, 0x00, 0xcc, 0x00, 0x02, 0x00, 0x00, 0xcc, 0x03,
+					0x11, 0x22, 0x33, 0xff, 0x33, 0x22, 0x11, 0xff, 0xaa, 0x33, 0xbb, 0xff,
+					0x00, 0x00, 0x00, 0xff, 0x33, 0x33, 0x33, 0xff, 0xff, 0xff, 0xff, 0xff,
+				},
+			},
+			&image.NRGBA{
+				Rect:   image.Rect(0, 0, 3, 3),
+				Stride: 3 * 4,
+				Pix: []uint8{
+					0x3d, 0x3d, 0x3d, 0x01, 0x78, 0x78, 0x78, 0x02, 0x17, 0x17, 0x17, 0x03,
+					0x1f, 0x1f, 0x1f, 0xff, 0x25, 0x25, 0x25, 0xff, 0x66, 0x66, 0x66, 0xff,
+					0x00, 0x00, 0x00, 0xff, 0x33, 0x33, 0x33, 0xff, 0xff, 0xff, 0xff, 0xff,
+				},
+			},
+		},
+	}
+	for _, d := range td {
+		got := Grayscale(d.src)
+		want := d.want
+		if !compareNRGBA(got, want, 0) {
+			t.Errorf("test [%s] failed: %#v", d.desc, got)
+		}
+	}
+}
+
+func TestInvert(t *testing.T) {
+	td := []struct {
+		desc string
+		src  image.Image
+		want *image.NRGBA
+	}{
+		{
+			"Invert 3x3",
+			&image.NRGBA{
+				Rect:   image.Rect(-1, -1, 2, 2),
+				Stride: 3 * 4,
+				Pix: []uint8{
+					0xcc, 0x00, 0x00, 0x01, 0x00, 0xcc, 0x00, 0x02, 0x00, 0x00, 0xcc, 0x03,
+					0x11, 0x22, 0x33, 0xff, 0x33, 0x22, 0x11, 0xff, 0xaa, 0x33, 0xbb, 0xff,
+					0x00, 0x00, 0x00, 0xff, 0x33, 0x33, 0x33, 0xff, 0xff, 0xff, 0xff, 0xff,
+				},
+			},
+			&image.NRGBA{
+				Rect:   image.Rect(0, 0, 3, 3),
+				Stride: 3 * 4,
+				Pix: []uint8{
+					0x33, 0xff, 0xff, 0x01, 0xff, 0x33, 0xff, 0x02, 0xff, 0xff, 0x33, 0x03,
+					0xee, 0xdd, 0xcc, 0xff, 0xcc, 0xdd, 0xee, 0xff, 0x55, 0xcc, 0x44, 0xff,
+					0xff, 0xff, 0xff, 0xff, 0xcc, 0xcc, 0xcc, 0xff, 0x00, 0x00, 0x00, 0xff,
+				},
+			},
+		},
+	}
+	for _, d := range td {
+		got := Invert(d.src)
+		want := d.want
+		if !compareNRGBA(got, want, 0) {
+			t.Errorf("test [%s] failed: %#v", d.desc, got)
+		}
+	}
+}
+
+func TestAdjustContrast(t *testing.T) {
+	td := []struct {
+		desc string
+		src  image.Image
+		p    float64
+		want *image.NRGBA
+	}{
+		{
+			"AdjustContrast 3x3 10",
+			&image.NRGBA{
+				Rect:   image.Rect(-1, -1, 2, 2),
+				Stride: 3 * 4,
+				Pix: []uint8{
+					0xcc, 0x00, 0x00, 0x01, 0x00, 0xcc, 0x00, 0x02, 0x00, 0x00, 0xcc, 0x03,
+					0x11, 0x22, 0x33, 0xff, 0x33, 0x22, 0x11, 0xff, 0xaa, 0x33, 0xbb, 0xff,
+					0x00, 0x00, 0x00, 0xff, 0x33, 0x33, 0x33, 0xff, 0xff, 0xff, 0xff, 0xff,
+				},
+			},
+			10,
+			&image.NRGBA{
+				Rect:   image.Rect(0, 0, 3, 3),
+				Stride: 3 * 4,
+				Pix: []uint8{
+					0xd5, 0x00, 0x00, 0x01, 0x00, 0xd5, 0x00, 0x02, 0x00, 0x00, 0xd5, 0x03,
+					0x05, 0x18, 0x2b, 0xff, 0x2b, 0x18, 0x05, 0xff, 0xaf, 0x2b, 0xc2, 0xff,
+					0x00, 0x00, 0x00, 0xff, 0x2b, 0x2b, 0x2b, 0xff, 0xff, 0xff, 0xff, 0xff,
+				},
+			},
+		},
+		{
+			"AdjustContrast 3x3 100",
+			&image.NRGBA{
+				Rect:   image.Rect(-1, -1, 2, 2),
+				Stride: 3 * 4,
+				Pix: []uint8{
+					0xcc, 0x00, 0x00, 0x01, 0x00, 0xcc, 0x00, 0x02, 0x00, 0x00, 0xcc, 0x03,
+					0x11, 0x22, 0x33, 0xff, 0x33, 0x22, 0x11, 0xff, 0xaa, 0x33, 0xbb, 0xff,
+					0x00, 0x00, 0x00, 0xff, 0x33, 0x33, 0x33, 0xff, 0xff, 0xff, 0xff, 0xff,
+				},
+			},
+			100,
+			&image.NRGBA{
+				Rect:   image.Rect(0, 0, 3, 3),
+				Stride: 3 * 4,
+				Pix: []uint8{
+					0xff, 0x00, 0x00, 0x01, 0x00, 0xff, 0x00, 0x02, 0x00, 0x00, 0xff, 0x03,
+					0x00, 0x00, 0x00, 0xff, 0x00, 0x00, 0x00, 0xff, 0xff, 0x00, 0xff, 0xff,
+					0x00, 0x00, 0x00, 0xff, 0x00, 0x00, 0x00, 0xff, 0xff, 0xff, 0xff, 0xff,
+				},
+			},
+		},
+		{
+			"AdjustContrast 3x3 -10",
+			&image.NRGBA{
+				Rect:   image.Rect(-1, -1, 2, 2),
+				Stride: 3 * 4,
+				Pix: []uint8{
+					0xcc, 0x00, 0x00, 0x01, 0x00, 0xcc, 0x00, 0x02, 0x00, 0x00, 0xcc, 0x03,
+					0x11, 0x22, 0x33, 0xff, 0x33, 0x22, 0x11, 0xff, 0xaa, 0x33, 0xbb, 0xff,
+					0x00, 0x00, 0x00, 0xff, 0x33, 0x33, 0x33, 0xff, 0xff, 0xff, 0xff, 0xff,
+				},
+			},
+			-10,
+			&image.NRGBA{
+				Rect:   image.Rect(0, 0, 3, 3),
+				Stride: 3 * 4,
+				Pix: []uint8{
+					0xc4, 0x0d, 0x0d, 0x01, 0x0d, 0xc4, 0x0d, 0x02, 0x0d, 0x0d, 0xc4, 0x03,
+					0x1c, 0x2b, 0x3b, 0xff, 0x3b, 0x2b, 0x1c, 0xff, 0xa6, 0x3b, 0xb5, 0xff,
+					0x0d, 0x0d, 0x0d, 0xff, 0x3b, 0x3b, 0x3b, 0xff, 0xf2, 0xf2, 0xf2, 0xff,
+				},
+			},
+		},
+		{
+			"AdjustContrast 3x3 -100",
+			&image.NRGBA{
+				Rect:   image.Rect(-1, -1, 2, 2),
+				Stride: 3 * 4,
+				Pix: []uint8{
+					0xcc, 0x00, 0x00, 0x01, 0x00, 0xcc, 0x00, 0x02, 0x00, 0x00, 0xcc, 0x03,
+					0x11, 0x22, 0x33, 0xff, 0x33, 0x22, 0x11, 0xff, 0xaa, 0x33, 0xbb, 0xff,
+					0x00, 0x00, 0x00, 0xff, 0x33, 0x33, 0x33, 0xff, 0xff, 0xff, 0xff, 0xff,
+				},
+			},
+			-100,
+			&image.NRGBA{
+				Rect:   image.Rect(0, 0, 3, 3),
+				Stride: 3 * 4,
+				Pix: []uint8{
+					0x80, 0x80, 0x80, 0x01, 0x80, 0x80, 0x80, 0x02, 0x80, 0x80, 0x80, 0x03,
+					0x80, 0x80, 0x80, 0xff, 0x80, 0x80, 0x80, 0xff, 0x80, 0x80, 0x80, 0xff,
+					0x80, 0x80, 0x80, 0xff, 0x80, 0x80, 0x80, 0xff, 0x80, 0x80, 0x80, 0xff,
+				},
+			},
+		},
+		{
+			"AdjustContrast 3x3 0",
+			&image.NRGBA{
+				Rect:   image.Rect(-1, -1, 2, 2),
+				Stride: 3 * 4,
+				Pix: []uint8{
+					0xcc, 0x00, 0x00, 0x01, 0x00, 0xcc, 0x00, 0x02, 0x00, 0x00, 0xcc, 0x03,
+					0x11, 0x22, 0x33, 0xff, 0x33, 0x22, 0x11, 0xff, 0xaa, 0x33, 0xbb, 0xff,
+					0x00, 0x00, 0x00, 0xff, 0x33, 0x33, 0x33, 0xff, 0xff, 0xff, 0xff, 0xff,
+				},
+			},
+			0,
+			&image.NRGBA{
+				Rect:   image.Rect(0, 0, 3, 3),
+				Stride: 3 * 4,
+				Pix: []uint8{
+					0xcc, 0x00, 0x00, 0x01, 0x00, 0xcc, 0x00, 0x02, 0x00, 0x00, 0xcc, 0x03,
+					0x11, 0x22, 0x33, 0xff, 0x33, 0x22, 0x11, 0xff, 0xaa, 0x33, 0xbb, 0xff,
+					0x00, 0x00, 0x00, 0xff, 0x33, 0x33, 0x33, 0xff, 0xff, 0xff, 0xff, 0xff,
+				},
+			},
+		},
+	}
+	for _, d := range td {
+		got := AdjustContrast(d.src, d.p)
+		want := d.want
+		if !compareNRGBA(got, want, 0) {
+			t.Errorf("test [%s] failed: %#v", d.desc, got)
+		}
+	}
+}
+
+func TestAdjustBrightness(t *testing.T) {
+	td := []struct {
+		desc string
+		src  image.Image
+		p    float64
+		want *image.NRGBA
+	}{
+		{
+			"AdjustBrightness 3x3 10",
+			&image.NRGBA{
+				Rect:   image.Rect(-1, -1, 2, 2),
+				Stride: 3 * 4,
+				Pix: []uint8{
+					0xcc, 0x00, 0x00, 0x01, 0x00, 0xcc, 0x00, 0x02, 0x00, 0x00, 0xcc, 0x03,
+					0x11, 0x22, 0x33, 0xff, 0x33, 0x22, 0x11, 0xff, 0xaa, 0x33, 0xbb, 0xff,
+					0x00, 0x00, 0x00, 0xff, 0x33, 0x33, 0x33, 0xff, 0xff, 0xff, 0xff, 0xff,
+				},
+			},
+			10,
+			&image.NRGBA{
+				Rect:   image.Rect(0, 0, 3, 3),
+				Stride: 3 * 4,
+				Pix: []uint8{
+					0xe6, 0x1a, 0x1a, 0x01, 0x1a, 0xe6, 0x1a, 0x02, 0x1a, 0x1a, 0xe6, 0x03,
+					0x2b, 0x3c, 0x4d, 0xff, 0x4d, 0x3c, 0x2b, 0xff, 0xc4, 0x4d, 0xd5, 0xff,
+					0x1a, 0x1a, 0x1a, 0xff, 0x4d, 0x4d, 0x4d, 0xff, 0xff, 0xff, 0xff, 0xff,
+				},
+			},
+		},
+		{
+			"AdjustBrightness 3x3 100",
+			&image.NRGBA{
+				Rect:   image.Rect(-1, -1, 2, 2),
+				Stride: 3 * 4,
+				Pix: []uint8{
+					0xcc, 0x00, 0x00, 0x01, 0x00, 0xcc, 0x00, 0x02, 0x00, 0x00, 0xcc, 0x03,
+					0x11, 0x22, 0x33, 0xff, 0x33, 0x22, 0x11, 0xff, 0xaa, 0x33, 0xbb, 0xff,
+					0x00, 0x00, 0x00, 0xff, 0x33, 0x33, 0x33, 0xff, 0xff, 0xff, 0xff, 0xff,
+				},
+			},
+			100,
+			&image.NRGBA{
+				Rect:   image.Rect(0, 0, 3, 3),
+				Stride: 3 * 4,
+				Pix: []uint8{
+					0xff, 0xff, 0xff, 0x01, 0xff, 0xff, 0xff, 0x02, 0xff, 0xff, 0xff, 0x03,
+					0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff,
+					0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff,
+				},
+			},
+		},
+		{
+			"AdjustBrightness 3x3 -10",
+			&image.NRGBA{
+				Rect:   image.Rect(-1, -1, 2, 2),
+				Stride: 3 * 4,
+				Pix: []uint8{
+					0xcc, 0x00, 0x00, 0x01, 0x00, 0xcc, 0x00, 0x02, 0x00, 0x00, 0xcc, 0x03,
+					0x11, 0x22, 0x33, 0xff, 0x33, 0x22, 0x11, 0xff, 0xaa, 0x33, 0xbb, 0xff,
+					0x00, 0x00, 0x00, 0xff, 0x33, 0x33, 0x33, 0xff, 0xff, 0xff, 0xff, 0xff,
+				},
+			},
+			-10,
+			&image.NRGBA{
+				Rect:   image.Rect(0, 0, 3, 3),
+				Stride: 3 * 4,
+				Pix: []uint8{
+					0xb3, 0x00, 0x00, 0x01, 0x00, 0xb3, 0x00, 0x02, 0x00, 0x00, 0xb3, 0x03,
+					0x00, 0x09, 0x1a, 0xff, 0x1a, 0x09, 0x00, 0xff, 0x91, 0x1a, 0xa2, 0xff,
+					0x00, 0x00, 0x00, 0xff, 0x1a, 0x1a, 0x1a, 0xff, 0xe6, 0xe6, 0xe6, 0xff,
+				},
+			},
+		},
+		{
+			"AdjustBrightness 3x3 -100",
+			&image.NRGBA{
+				Rect:   image.Rect(-1, -1, 2, 2),
+				Stride: 3 * 4,
+				Pix: []uint8{
+					0xcc, 0x00, 0x00, 0x01, 0x00, 0xcc, 0x00, 0x02, 0x00, 0x00, 0xcc, 0x03,
+					0x11, 0x22, 0x33, 0xff, 0x33, 0x22, 0x11, 0xff, 0xaa, 0x33, 0xbb, 0xff,
+					0x00, 0x00, 0x00, 0xff, 0x33, 0x33, 0x33, 0xff, 0xff, 0xff, 0xff, 0xff,
+				},
+			},
+			-100,
+			&image.NRGBA{
+				Rect:   image.Rect(0, 0, 3, 3),
+				Stride: 3 * 4,
+				Pix: []uint8{
+					0x00, 0x00, 0x00, 0x01, 0x00, 0x00, 0x00, 0x02, 0x00, 0x00, 0x00, 0x03,
+					0x00, 0x00, 0x00, 0xff, 0x00, 0x00, 0x00, 0xff, 0x00, 0x00, 0x00, 0xff,
+					0x00, 0x00, 0x00, 0xff, 0x00, 0x00, 0x00, 0xff, 0x00, 0x00, 0x00, 0xff,
+				},
+			},
+		},
+		{
+			"AdjustBrightness 3x3 0",
+			&image.NRGBA{
+				Rect:   image.Rect(-1, -1, 2, 2),
+				Stride: 3 * 4,
+				Pix: []uint8{
+					0xcc, 0x00, 0x00, 0x01, 0x00, 0xcc, 0x00, 0x02, 0x00, 0x00, 0xcc, 0x03,
+					0x11, 0x22, 0x33, 0xff, 0x33, 0x22, 0x11, 0xff, 0xaa, 0x33, 0xbb, 0xff,
+					0x00, 0x00, 0x00, 0xff, 0x33, 0x33, 0x33, 0xff, 0xff, 0xff, 0xff, 0xff,
+				},
+			},
+			0,
+			&image.NRGBA{
+				Rect:   image.Rect(0, 0, 3, 3),
+				Stride: 3 * 4,
+				Pix: []uint8{
+					0xcc, 0x00, 0x00, 0x01, 0x00, 0xcc, 0x00, 0x02, 0x00, 0x00, 0xcc, 0x03,
+					0x11, 0x22, 0x33, 0xff, 0x33, 0x22, 0x11, 0xff, 0xaa, 0x33, 0xbb, 0xff,
+					0x00, 0x00, 0x00, 0xff, 0x33, 0x33, 0x33, 0xff, 0xff, 0xff, 0xff, 0xff,
+				},
+			},
+		},
+	}
+	for _, d := range td {
+		got := AdjustBrightness(d.src, d.p)
+		want := d.want
+		if !compareNRGBA(got, want, 0) {
+			t.Errorf("test [%s] failed: %#v", d.desc, got)
+		}
+	}
+}
+
+func TestAdjustGamma(t *testing.T) {
+	td := []struct {
+		desc string
+		src  image.Image
+		p    float64
+		want *image.NRGBA
+	}{
+		{
+			"AdjustGamma 3x3 0.75",
+			&image.NRGBA{
+				Rect:   image.Rect(-1, -1, 2, 2),
+				Stride: 3 * 4,
+				Pix: []uint8{
+					0xcc, 0x00, 0x00, 0x01, 0x00, 0xcc, 0x00, 0x02, 0x00, 0x00, 0xcc, 0x03,
+					0x11, 0x22, 0x33, 0xff, 0x33, 0x22, 0x11, 0xff, 0xaa, 0x33, 0xbb, 0xff,
+					0x00, 0x00, 0x00, 0xff, 0x33, 0x33, 0x33, 0xff, 0xff, 0xff, 0xff, 0xff,
+				},
+			},
+			0.75,
+			&image.NRGBA{
+				Rect:   image.Rect(0, 0, 3, 3),
+				Stride: 3 * 4,
+				Pix: []uint8{
+					0xbd, 0x00, 0x00, 0x01, 0x00, 0xbd, 0x00, 0x02, 0x00, 0x00, 0xbd, 0x03,
+					0x07, 0x11, 0x1e, 0xff, 0x1e, 0x11, 0x07, 0xff, 0x95, 0x1e, 0xa9, 0xff,
+					0x00, 0x00, 0x00, 0xff, 0x1e, 0x1e, 0x1e, 0xff, 0xff, 0xff, 0xff, 0xff,
+				},
+			},
+		},
+		{
+			"AdjustGamma 3x3 1.5",
+			&image.NRGBA{
+				Rect:   image.Rect(-1, -1, 2, 2),
+				Stride: 3 * 4,
+				Pix: []uint8{
+					0xcc, 0x00, 0x00, 0x01, 0x00, 0xcc, 0x00, 0x02, 0x00, 0x00, 0xcc, 0x03,
+					0x11, 0x22, 0x33, 0xff, 0x33, 0x22, 0x11, 0xff, 0xaa, 0x33, 0xbb, 0xff,
+					0x00, 0x00, 0x00, 0xff, 0x33, 0x33, 0x33, 0xff, 0xff, 0xff, 0xff, 0xff,
+				},
+			},
+			1.5,
+			&image.NRGBA{
+				Rect:   image.Rect(0, 0, 3, 3),
+				Stride: 3 * 4,
+				Pix: []uint8{
+					0xdc, 0x00, 0x00, 0x01, 0x00, 0xdc, 0x00, 0x02, 0x00, 0x00, 0xdc, 0x03,
+					0x2a, 0x43, 0x57, 0xff, 0x57, 0x43, 0x2a, 0xff, 0xc3, 0x57, 0xcf, 0xff,
+					0x00, 0x00, 0x00, 0xff, 0x57, 0x57, 0x57, 0xff, 0xff, 0xff, 0xff, 0xff,
+				},
+			},
+		},
+		{
+			"AdjustGamma 3x3 1.0",
+			&image.NRGBA{
+				Rect:   image.Rect(-1, -1, 2, 2),
+				Stride: 3 * 4,
+				Pix: []uint8{
+					0xcc, 0x00, 0x00, 0x01, 0x00, 0xcc, 0x00, 0x02, 0x00, 0x00, 0xcc, 0x03,
+					0x11, 0x22, 0x33, 0xff, 0x33, 0x22, 0x11, 0xff, 0xaa, 0x33, 0xbb, 0xff,
+					0x00, 0x00, 0x00, 0xff, 0x33, 0x33, 0x33, 0xff, 0xff, 0xff, 0xff, 0xff,
+				},
+			},
+			1.0,
+			&image.NRGBA{
+				Rect:   image.Rect(0, 0, 3, 3),
+				Stride: 3 * 4,
+				Pix: []uint8{
+					0xcc, 0x00, 0x00, 0x01, 0x00, 0xcc, 0x00, 0x02, 0x00, 0x00, 0xcc, 0x03,
+					0x11, 0x22, 0x33, 0xff, 0x33, 0x22, 0x11, 0xff, 0xaa, 0x33, 0xbb, 0xff,
+					0x00, 0x00, 0x00, 0xff, 0x33, 0x33, 0x33, 0xff, 0xff, 0xff, 0xff, 0xff,
+				},
+			},
+		},
+	}
+	for _, d := range td {
+		got := AdjustGamma(d.src, d.p)
+		want := d.want
+		if !compareNRGBA(got, want, 0) {
+			t.Errorf("test [%s] failed: %#v", d.desc, got)
+		}
+	}
+}
+
+func TestAdjustSigmoid(t *testing.T) {
+	td := []struct {
+		desc string
+		src  image.Image
+		m    float64
+		p    float64
+		want *image.NRGBA
+	}{
+		{
+			"AdjustSigmoid 3x3 0.5 3.0",
+			&image.NRGBA{
+				Rect:   image.Rect(-1, -1, 2, 2),
+				Stride: 3 * 4,
+				Pix: []uint8{
+					0xcc, 0x00, 0x00, 0x01, 0x00, 0xcc, 0x00, 0x02, 0x00, 0x00, 0xcc, 0x03,
+					0x11, 0x22, 0x33, 0xff, 0x33, 0x22, 0x11, 0xff, 0xaa, 0x33, 0xbb, 0xff,
+					0x00, 0x00, 0x00, 0xff, 0x33, 0x33, 0x33, 0xff, 0xff, 0xff, 0xff, 0xff,
+				},
+			},
+			0.5,
+			3.0,
+			&image.NRGBA{
+				Rect:   image.Rect(0, 0, 3, 3),
+				Stride: 3 * 4,
+				Pix: []uint8{
+					0xd4, 0x00, 0x00, 0x01, 0x00, 0xd4, 0x00, 0x02, 0x00, 0x00, 0xd4, 0x03,
+					0x0d, 0x1b, 0x2b, 0xff, 0x2b, 0x1b, 0x0d, 0xff, 0xb1, 0x2b, 0xc3, 0xff,
+					0x00, 0x00, 0x00, 0xff, 0x2b, 0x2b, 0x2b, 0xff, 0xff, 0xff, 0xff, 0xff,
+				},
+			},
+		},
+		{
+			"AdjustSigmoid 3x3 0.5 -3.0",
+			&image.NRGBA{
+				Rect:   image.Rect(-1, -1, 2, 2),
+				Stride: 3 * 4,
+				Pix: []uint8{
+					0xcc, 0x00, 0x00, 0x01, 0x00, 0xcc, 0x00, 0x02, 0x00, 0x00, 0xcc, 0x03,
+					0x11, 0x22, 0x33, 0xff, 0x33, 0x22, 0x11, 0xff, 0xaa, 0x33, 0xbb, 0xff,
+					0x00, 0x00, 0x00, 0xff, 0x33, 0x33, 0x33, 0xff, 0xff, 0xff, 0xff, 0xff,
+				},
+			},
+			0.5,
+			-3.0,
+			&image.NRGBA{
+				Rect:   image.Rect(0, 0, 3, 3),
+				Stride: 3 * 4,
+				Pix: []uint8{
+					0xc4, 0x00, 0x00, 0x01, 0x00, 0xc4, 0x00, 0x02, 0x00, 0x00, 0xc4, 0x03,
+					0x16, 0x2a, 0x3b, 0xff, 0x3b, 0x2a, 0x16, 0xff, 0xa4, 0x3b, 0xb3, 0xff,
+					0x00, 0x00, 0x00, 0xff, 0x3b, 0x3b, 0x3b, 0xff, 0xff, 0xff, 0xff, 0xff,
+				},
+			},
+		},
+		{
+			"AdjustSigmoid 3x3 0.5 0.0",
+			&image.NRGBA{
+				Rect:   image.Rect(-1, -1, 2, 2),
+				Stride: 3 * 4,
+				Pix: []uint8{
+					0xcc, 0x00, 0x00, 0x01, 0x00, 0xcc, 0x00, 0x02, 0x00, 0x00, 0xcc, 0x03,
+					0x11, 0x22, 0x33, 0xff, 0x33, 0x22, 0x11, 0xff, 0xaa, 0x33, 0xbb, 0xff,
+					0x00, 0x00, 0x00, 0xff, 0x33, 0x33, 0x33, 0xff, 0xff, 0xff, 0xff, 0xff,
+				},
+			},
+			0.5,
+			0.0,
+			&image.NRGBA{
+				Rect:   image.Rect(0, 0, 3, 3),
+				Stride: 3 * 4,
+				Pix: []uint8{
+					0xcc, 0x00, 0x00, 0x01, 0x00, 0xcc, 0x00, 0x02, 0x00, 0x00, 0xcc, 0x03,
+					0x11, 0x22, 0x33, 0xff, 0x33, 0x22, 0x11, 0xff, 0xaa, 0x33, 0xbb, 0xff,
+					0x00, 0x00, 0x00, 0xff, 0x33, 0x33, 0x33, 0xff, 0xff, 0xff, 0xff, 0xff,
+				},
+			},
+		},
+	}
+	for _, d := range td {
+		got := AdjustSigmoid(d.src, d.m, d.p)
+		want := d.want
+		if !compareNRGBA(got, want, 0) {
+			t.Errorf("test [%s] failed: %#v", d.desc, got)
+		}
+	}
+}