imaging/effects_test.go

package imaging

import (
	"image"
	"testing"
)

func TestBlur(t *testing.T) {
	td := []struct {
		desc  string
		src   image.Image
		sigma float64
		want  *image.NRGBA
	}{
		{
			"Blur 3x3 0.5",
			&image.NRGBA{
				Rect:   image.Rect(-1, -1, 2, 2),
				Stride: 3 * 4,
				Pix: []uint8{
					0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
					0x00, 0x00, 0x00, 0x00, 0x66, 0xaa, 0xff, 0xff, 0x00, 0x00, 0x00, 0x00,
					0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
				},
			},
			0.5,
			&image.NRGBA{
				Rect:   image.Rect(0, 0, 3, 3),
				Stride: 3 * 4,
				Pix: []uint8{
					0x01, 0x02, 0x04, 0x04, 0x0a, 0x10, 0x18, 0x18, 0x01, 0x02, 0x04, 0x04,
					0x09, 0x10, 0x18, 0x18, 0x3f, 0x69, 0x9e, 0x9e, 0x09, 0x10, 0x18, 0x18,
					0x01, 0x02, 0x04, 0x04, 0x0a, 0x10, 0x18, 0x18, 0x01, 0x02, 0x04, 0x04,
				},
			},
		},
		{

			"Blur 3x3 10",
			&image.NRGBA{
				Rect:   image.Rect(-1, -1, 2, 2),
				Stride: 3 * 4,
				Pix: []uint8{
					0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
					0x00, 0x00, 0x00, 0x00, 0x66, 0xaa, 0xff, 0xff, 0x00, 0x00, 0x00, 0x00,
					0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
				},
			},
			10,
			&image.NRGBA{
				Rect:   image.Rect(0, 0, 3, 3),
				Stride: 3 * 4,
				Pix: []uint8{
					0x0b, 0x13, 0x1c, 0x1c, 0x0b, 0x13, 0x1c, 0x1c, 0x0b, 0x13, 0x1c, 0x1c,
					0x0b, 0x13, 0x1c, 0x1c, 0x0b, 0x13, 0x1c, 0x1c, 0x0b, 0x13, 0x1c, 0x1c,
					0x0b, 0x13, 0x1c, 0x1c, 0x0b, 0x13, 0x1c, 0x1c, 0x0b, 0x13, 0x1c, 0x1c,
				},
			},
		},
	}
	for _, d := range td {
		got := Blur(d.src, d.sigma)
		want := d.want
		if !compareNRGBA(got, want, 0) {
			t.Errorf("test [%s] failed: %#v", d.desc, got)
		}
	}
}

func TestSharpen(t *testing.T) {
	td := []struct {
		desc  string
		src   image.Image
		sigma float64
		want  *image.NRGBA
	}{
		{
			"Sharpen 3x3 0.5",
			&image.NRGBA{
				Rect:   image.Rect(-1, -1, 2, 2),
				Stride: 3 * 4,
				Pix: []uint8{
					0x66, 0x66, 0x66, 0x66, 0x66, 0x66, 0x66, 0x66, 0x66, 0x66, 0x66, 0x66,
					0x66, 0x66, 0x66, 0x66, 0x77, 0x77, 0x77, 0x77, 0x66, 0x66, 0x66, 0x66,
					0x66, 0x66, 0x66, 0x66, 0x66, 0x66, 0x66, 0x66, 0x66, 0x66, 0x66, 0x66,
				},
			},
			0.5,
			&image.NRGBA{
				Rect:   image.Rect(0, 0, 3, 3),
				Stride: 3 * 4,
				Pix: []uint8{
					0x66, 0x66, 0x66, 0x66, 0x64, 0x64, 0x64, 0x64, 0x66, 0x66, 0x66, 0x66,
					0x64, 0x64, 0x64, 0x64, 0x7e, 0x7e, 0x7e, 0x7e, 0x64, 0x64, 0x64, 0x64,
					0x66, 0x66, 0x66, 0x66, 0x64, 0x64, 0x64, 0x64, 0x66, 0x66, 0x66, 0x66},
			},
		},
		{

			"Sharpen 3x3 10",
			&image.NRGBA{
				Rect:   image.Rect(-1, -1, 2, 2),
				Stride: 3 * 4,
				Pix: []uint8{
					0x66, 0x66, 0x66, 0x66, 0x66, 0x66, 0x66, 0x66, 0x66, 0x66, 0x66, 0x66,
					0x66, 0x66, 0x66, 0x66, 0x77, 0x77, 0x77, 0x77, 0x66, 0x66, 0x66, 0x66,
					0x66, 0x66, 0x66, 0x66, 0x66, 0x66, 0x66, 0x66, 0x66, 0x66, 0x66, 0x66},
			},
			100,
			&image.NRGBA{
				Rect:   image.Rect(0, 0, 3, 3),
				Stride: 3 * 4,
				Pix: []uint8{
					0x64, 0x64, 0x64, 0x64, 0x64, 0x64, 0x64, 0x64, 0x64, 0x64, 0x64, 0x64,
					0x64, 0x64, 0x64, 0x64, 0x86, 0x86, 0x86, 0x86, 0x64, 0x64, 0x64, 0x64,
					0x64, 0x64, 0x64, 0x64, 0x64, 0x64, 0x64, 0x64, 0x64, 0x64, 0x64, 0x64,
				},
			},
		},
	}
	for _, d := range td {
		got := Sharpen(d.src, d.sigma)
		want := d.want
		if !compareNRGBA(got, want, 0) {
			t.Errorf("test [%s] failed: %#v", d.desc, got)
		}
	}
}