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-rw-r--r--vendor/golang.org/x/image/draw/scale_test.go731
1 files changed, 731 insertions, 0 deletions
diff --git a/vendor/golang.org/x/image/draw/scale_test.go b/vendor/golang.org/x/image/draw/scale_test.go
new file mode 100644
index 000000000..5e184c24e
--- /dev/null
+++ b/vendor/golang.org/x/image/draw/scale_test.go
@@ -0,0 +1,731 @@
+// Copyright 2015 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package draw
+
+import (
+ "bytes"
+ "flag"
+ "fmt"
+ "image"
+ "image/color"
+ "image/png"
+ "math/rand"
+ "os"
+ "reflect"
+ "testing"
+
+ "golang.org/x/image/math/f64"
+
+ _ "image/jpeg"
+)
+
+var genGoldenFiles = flag.Bool("gen_golden_files", false, "whether to generate the TestXxx golden files.")
+
+var transformMatrix = func(scale, tx, ty float64) f64.Aff3 {
+ const cos30, sin30 = 0.866025404, 0.5
+ return f64.Aff3{
+ +scale * cos30, -scale * sin30, tx,
+ +scale * sin30, +scale * cos30, ty,
+ }
+}
+
+func encode(filename string, m image.Image) error {
+ f, err := os.Create(filename)
+ if err != nil {
+ return fmt.Errorf("Create: %v", err)
+ }
+ defer f.Close()
+ if err := png.Encode(f, m); err != nil {
+ return fmt.Errorf("Encode: %v", err)
+ }
+ return nil
+}
+
+// testInterp tests that interpolating the source image gives the exact
+// destination image. This is to ensure that any refactoring or optimization of
+// the interpolation code doesn't change the behavior. Changing the actual
+// algorithm or kernel used by any particular quality setting will obviously
+// change the resultant pixels. In such a case, use the gen_golden_files flag
+// to regenerate the golden files.
+func testInterp(t *testing.T, w int, h int, direction, prefix, suffix string) {
+ f, err := os.Open("../testdata/" + prefix + suffix)
+ if err != nil {
+ t.Fatalf("Open: %v", err)
+ }
+ defer f.Close()
+ src, _, err := image.Decode(f)
+ if err != nil {
+ t.Fatalf("Decode: %v", err)
+ }
+
+ op, scale := Src, 3.75
+ if prefix == "tux" {
+ op, scale = Over, 0.125
+ }
+ green := image.NewUniform(color.RGBA{0x00, 0x22, 0x11, 0xff})
+
+ testCases := map[string]Interpolator{
+ "nn": NearestNeighbor,
+ "ab": ApproxBiLinear,
+ "bl": BiLinear,
+ "cr": CatmullRom,
+ }
+ for name, q := range testCases {
+ goldenFilename := fmt.Sprintf("../testdata/%s-%s-%s.png", prefix, direction, name)
+
+ got := image.NewRGBA(image.Rect(0, 0, w, h))
+ Copy(got, image.Point{}, green, got.Bounds(), Src, nil)
+ if direction == "rotate" {
+ q.Transform(got, transformMatrix(scale, 40, 10), src, src.Bounds(), op, nil)
+ } else {
+ q.Scale(got, got.Bounds(), src, src.Bounds(), op, nil)
+ }
+
+ if *genGoldenFiles {
+ if err := encode(goldenFilename, got); err != nil {
+ t.Error(err)
+ }
+ continue
+ }
+
+ g, err := os.Open(goldenFilename)
+ if err != nil {
+ t.Errorf("Open: %v", err)
+ continue
+ }
+ defer g.Close()
+ wantRaw, err := png.Decode(g)
+ if err != nil {
+ t.Errorf("Decode: %v", err)
+ continue
+ }
+ // convert wantRaw to RGBA.
+ want, ok := wantRaw.(*image.RGBA)
+ if !ok {
+ b := wantRaw.Bounds()
+ want = image.NewRGBA(b)
+ Draw(want, b, wantRaw, b.Min, Src)
+ }
+
+ if !reflect.DeepEqual(got, want) {
+ t.Errorf("%s: actual image differs from golden image", goldenFilename)
+ continue
+ }
+ }
+}
+
+func TestScaleDown(t *testing.T) { testInterp(t, 100, 100, "down", "go-turns-two", "-280x360.jpeg") }
+func TestScaleUp(t *testing.T) { testInterp(t, 75, 100, "up", "go-turns-two", "-14x18.png") }
+func TestTformSrc(t *testing.T) { testInterp(t, 100, 100, "rotate", "go-turns-two", "-14x18.png") }
+func TestTformOver(t *testing.T) { testInterp(t, 100, 100, "rotate", "tux", ".png") }
+
+// TestSimpleTransforms tests Scale and Transform calls that simplify to Copy
+// or Scale calls.
+func TestSimpleTransforms(t *testing.T) {
+ f, err := os.Open("../testdata/testpattern.png") // A 100x100 image.
+ if err != nil {
+ t.Fatalf("Open: %v", err)
+ }
+ defer f.Close()
+ src, _, err := image.Decode(f)
+ if err != nil {
+ t.Fatalf("Decode: %v", err)
+ }
+
+ dst0 := image.NewRGBA(image.Rect(0, 0, 120, 150))
+ dst1 := image.NewRGBA(image.Rect(0, 0, 120, 150))
+ for _, op := range []string{"scale/copy", "tform/copy", "tform/scale"} {
+ for _, epsilon := range []float64{0, 1e-50, 1e-1} {
+ Copy(dst0, image.Point{}, image.Transparent, dst0.Bounds(), Src, nil)
+ Copy(dst1, image.Point{}, image.Transparent, dst1.Bounds(), Src, nil)
+
+ switch op {
+ case "scale/copy":
+ dr := image.Rect(10, 30, 10+100, 30+100)
+ if epsilon > 1e-10 {
+ dr.Max.X++
+ }
+ Copy(dst0, image.Point{10, 30}, src, src.Bounds(), Src, nil)
+ ApproxBiLinear.Scale(dst1, dr, src, src.Bounds(), Src, nil)
+ case "tform/copy":
+ Copy(dst0, image.Point{10, 30}, src, src.Bounds(), Src, nil)
+ ApproxBiLinear.Transform(dst1, f64.Aff3{
+ 1, 0 + epsilon, 10,
+ 0, 1, 30,
+ }, src, src.Bounds(), Src, nil)
+ case "tform/scale":
+ ApproxBiLinear.Scale(dst0, image.Rect(10, 50, 10+50, 50+50), src, src.Bounds(), Src, nil)
+ ApproxBiLinear.Transform(dst1, f64.Aff3{
+ 0.5, 0.0 + epsilon, 10,
+ 0.0, 0.5, 50,
+ }, src, src.Bounds(), Src, nil)
+ }
+
+ differ := !bytes.Equal(dst0.Pix, dst1.Pix)
+ if epsilon > 1e-10 {
+ if !differ {
+ t.Errorf("%s yielded same pixels, want different pixels: epsilon=%v", op, epsilon)
+ }
+ } else {
+ if differ {
+ t.Errorf("%s yielded different pixels, want same pixels: epsilon=%v", op, epsilon)
+ }
+ }
+ }
+ }
+}
+
+func BenchmarkSimpleScaleCopy(b *testing.B) {
+ dst := image.NewRGBA(image.Rect(0, 0, 640, 480))
+ src := image.NewRGBA(image.Rect(0, 0, 400, 300))
+ b.ResetTimer()
+ for i := 0; i < b.N; i++ {
+ ApproxBiLinear.Scale(dst, image.Rect(10, 20, 10+400, 20+300), src, src.Bounds(), Src, nil)
+ }
+}
+
+func BenchmarkSimpleTransformCopy(b *testing.B) {
+ dst := image.NewRGBA(image.Rect(0, 0, 640, 480))
+ src := image.NewRGBA(image.Rect(0, 0, 400, 300))
+ b.ResetTimer()
+ for i := 0; i < b.N; i++ {
+ ApproxBiLinear.Transform(dst, f64.Aff3{
+ 1, 0, 10,
+ 0, 1, 20,
+ }, src, src.Bounds(), Src, nil)
+ }
+}
+
+func BenchmarkSimpleTransformScale(b *testing.B) {
+ dst := image.NewRGBA(image.Rect(0, 0, 640, 480))
+ src := image.NewRGBA(image.Rect(0, 0, 400, 300))
+ b.ResetTimer()
+ for i := 0; i < b.N; i++ {
+ ApproxBiLinear.Transform(dst, f64.Aff3{
+ 0.5, 0.0, 10,
+ 0.0, 0.5, 20,
+ }, src, src.Bounds(), Src, nil)
+ }
+}
+
+func TestOps(t *testing.T) {
+ blue := image.NewUniform(color.RGBA{0x00, 0x00, 0xff, 0xff})
+ testCases := map[Op]color.RGBA{
+ Over: color.RGBA{0x7f, 0x00, 0x80, 0xff},
+ Src: color.RGBA{0x7f, 0x00, 0x00, 0x7f},
+ }
+ for op, want := range testCases {
+ dst := image.NewRGBA(image.Rect(0, 0, 2, 2))
+ Copy(dst, image.Point{}, blue, dst.Bounds(), Src, nil)
+
+ src := image.NewRGBA(image.Rect(0, 0, 1, 1))
+ src.SetRGBA(0, 0, color.RGBA{0x7f, 0x00, 0x00, 0x7f})
+
+ NearestNeighbor.Scale(dst, dst.Bounds(), src, src.Bounds(), op, nil)
+
+ if got := dst.RGBAAt(0, 0); got != want {
+ t.Errorf("op=%v: got %v, want %v", op, got, want)
+ }
+ }
+}
+
+// TestNegativeWeights tests that scaling by a kernel that produces negative
+// weights, such as the Catmull-Rom kernel, doesn't produce an invalid color
+// according to Go's alpha-premultiplied model.
+func TestNegativeWeights(t *testing.T) {
+ check := func(m *image.RGBA) error {
+ b := m.Bounds()
+ for y := b.Min.Y; y < b.Max.Y; y++ {
+ for x := b.Min.X; x < b.Max.X; x++ {
+ if c := m.RGBAAt(x, y); c.R > c.A || c.G > c.A || c.B > c.A {
+ return fmt.Errorf("invalid color.RGBA at (%d, %d): %v", x, y, c)
+ }
+ }
+ }
+ return nil
+ }
+
+ src := image.NewRGBA(image.Rect(0, 0, 16, 16))
+ for y := 0; y < 16; y++ {
+ for x := 0; x < 16; x++ {
+ a := y * 0x11
+ src.Set(x, y, color.RGBA{
+ R: uint8(x * 0x11 * a / 0xff),
+ A: uint8(a),
+ })
+ }
+ }
+ if err := check(src); err != nil {
+ t.Fatalf("src image: %v", err)
+ }
+
+ dst := image.NewRGBA(image.Rect(0, 0, 32, 32))
+ CatmullRom.Scale(dst, dst.Bounds(), src, src.Bounds(), Over, nil)
+ if err := check(dst); err != nil {
+ t.Fatalf("dst image: %v", err)
+ }
+}
+
+func fillPix(r *rand.Rand, pixs ...[]byte) {
+ for _, pix := range pixs {
+ for i := range pix {
+ pix[i] = uint8(r.Intn(256))
+ }
+ }
+}
+
+func TestInterpClipCommute(t *testing.T) {
+ src := image.NewNRGBA(image.Rect(0, 0, 20, 20))
+ fillPix(rand.New(rand.NewSource(0)), src.Pix)
+
+ outer := image.Rect(1, 1, 8, 5)
+ inner := image.Rect(2, 3, 6, 5)
+ qs := []Interpolator{
+ NearestNeighbor,
+ ApproxBiLinear,
+ CatmullRom,
+ }
+ for _, transform := range []bool{false, true} {
+ for _, q := range qs {
+ dst0 := image.NewRGBA(image.Rect(1, 1, 10, 10))
+ dst1 := image.NewRGBA(image.Rect(1, 1, 10, 10))
+ for i := range dst0.Pix {
+ dst0.Pix[i] = uint8(i / 4)
+ dst1.Pix[i] = uint8(i / 4)
+ }
+
+ var interp func(dst *image.RGBA)
+ if transform {
+ interp = func(dst *image.RGBA) {
+ q.Transform(dst, transformMatrix(3.75, 2, 1), src, src.Bounds(), Over, nil)
+ }
+ } else {
+ interp = func(dst *image.RGBA) {
+ q.Scale(dst, outer, src, src.Bounds(), Over, nil)
+ }
+ }
+
+ // Interpolate then clip.
+ interp(dst0)
+ dst0 = dst0.SubImage(inner).(*image.RGBA)
+
+ // Clip then interpolate.
+ dst1 = dst1.SubImage(inner).(*image.RGBA)
+ interp(dst1)
+
+ loop:
+ for y := inner.Min.Y; y < inner.Max.Y; y++ {
+ for x := inner.Min.X; x < inner.Max.X; x++ {
+ if c0, c1 := dst0.RGBAAt(x, y), dst1.RGBAAt(x, y); c0 != c1 {
+ t.Errorf("q=%T: at (%d, %d): c0=%v, c1=%v", q, x, y, c0, c1)
+ break loop
+ }
+ }
+ }
+ }
+ }
+}
+
+// translatedImage is an image m translated by t.
+type translatedImage struct {
+ m image.Image
+ t image.Point
+}
+
+func (t *translatedImage) At(x, y int) color.Color { return t.m.At(x-t.t.X, y-t.t.Y) }
+func (t *translatedImage) Bounds() image.Rectangle { return t.m.Bounds().Add(t.t) }
+func (t *translatedImage) ColorModel() color.Model { return t.m.ColorModel() }
+
+// TestSrcTranslationInvariance tests that Scale and Transform are invariant
+// under src translations. Specifically, when some source pixels are not in the
+// bottom-right quadrant of src coordinate space, we consistently round down,
+// not round towards zero.
+func TestSrcTranslationInvariance(t *testing.T) {
+ f, err := os.Open("../testdata/testpattern.png")
+ if err != nil {
+ t.Fatalf("Open: %v", err)
+ }
+ defer f.Close()
+ src, _, err := image.Decode(f)
+ if err != nil {
+ t.Fatalf("Decode: %v", err)
+ }
+ sr := image.Rect(2, 3, 16, 12)
+ if !sr.In(src.Bounds()) {
+ t.Fatalf("src bounds too small: got %v", src.Bounds())
+ }
+ qs := []Interpolator{
+ NearestNeighbor,
+ ApproxBiLinear,
+ CatmullRom,
+ }
+ deltas := []image.Point{
+ {+0, +0},
+ {+0, +5},
+ {+0, -5},
+ {+5, +0},
+ {-5, +0},
+ {+8, +8},
+ {+8, -8},
+ {-8, +8},
+ {-8, -8},
+ }
+ m00 := transformMatrix(3.75, 0, 0)
+
+ for _, transform := range []bool{false, true} {
+ for _, q := range qs {
+ want := image.NewRGBA(image.Rect(0, 0, 20, 20))
+ if transform {
+ q.Transform(want, m00, src, sr, Over, nil)
+ } else {
+ q.Scale(want, want.Bounds(), src, sr, Over, nil)
+ }
+ for _, delta := range deltas {
+ tsrc := &translatedImage{src, delta}
+ got := image.NewRGBA(image.Rect(0, 0, 20, 20))
+ if transform {
+ m := matMul(&m00, &f64.Aff3{
+ 1, 0, -float64(delta.X),
+ 0, 1, -float64(delta.Y),
+ })
+ q.Transform(got, m, tsrc, sr.Add(delta), Over, nil)
+ } else {
+ q.Scale(got, got.Bounds(), tsrc, sr.Add(delta), Over, nil)
+ }
+ if !bytes.Equal(got.Pix, want.Pix) {
+ t.Errorf("pix differ for delta=%v, transform=%t, q=%T", delta, transform, q)
+ }
+ }
+ }
+ }
+}
+
+func TestSrcMask(t *testing.T) {
+ srcMask := image.NewRGBA(image.Rect(0, 0, 23, 1))
+ srcMask.SetRGBA(19, 0, color.RGBA{0x00, 0x00, 0x00, 0x7f})
+ srcMask.SetRGBA(20, 0, color.RGBA{0x00, 0x00, 0x00, 0xff})
+ srcMask.SetRGBA(21, 0, color.RGBA{0x00, 0x00, 0x00, 0x3f})
+ srcMask.SetRGBA(22, 0, color.RGBA{0x00, 0x00, 0x00, 0x00})
+ red := image.NewUniform(color.RGBA{0xff, 0x00, 0x00, 0xff})
+ blue := image.NewUniform(color.RGBA{0x00, 0x00, 0xff, 0xff})
+ dst := image.NewRGBA(image.Rect(0, 0, 6, 1))
+ Copy(dst, image.Point{}, blue, dst.Bounds(), Src, nil)
+ NearestNeighbor.Scale(dst, dst.Bounds(), red, image.Rect(0, 0, 3, 1), Over, &Options{
+ SrcMask: srcMask,
+ SrcMaskP: image.Point{20, 0},
+ })
+ got := [6]color.RGBA{
+ dst.RGBAAt(0, 0),
+ dst.RGBAAt(1, 0),
+ dst.RGBAAt(2, 0),
+ dst.RGBAAt(3, 0),
+ dst.RGBAAt(4, 0),
+ dst.RGBAAt(5, 0),
+ }
+ want := [6]color.RGBA{
+ {0xff, 0x00, 0x00, 0xff},
+ {0xff, 0x00, 0x00, 0xff},
+ {0x3f, 0x00, 0xc0, 0xff},
+ {0x3f, 0x00, 0xc0, 0xff},
+ {0x00, 0x00, 0xff, 0xff},
+ {0x00, 0x00, 0xff, 0xff},
+ }
+ if got != want {
+ t.Errorf("\ngot %v\nwant %v", got, want)
+ }
+}
+
+func TestDstMask(t *testing.T) {
+ dstMask := image.NewRGBA(image.Rect(0, 0, 23, 1))
+ dstMask.SetRGBA(19, 0, color.RGBA{0x00, 0x00, 0x00, 0x7f})
+ dstMask.SetRGBA(20, 0, color.RGBA{0x00, 0x00, 0x00, 0xff})
+ dstMask.SetRGBA(21, 0, color.RGBA{0x00, 0x00, 0x00, 0x3f})
+ dstMask.SetRGBA(22, 0, color.RGBA{0x00, 0x00, 0x00, 0x00})
+ red := image.NewRGBA(image.Rect(0, 0, 1, 1))
+ red.SetRGBA(0, 0, color.RGBA{0xff, 0x00, 0x00, 0xff})
+ blue := image.NewUniform(color.RGBA{0x00, 0x00, 0xff, 0xff})
+ qs := []Interpolator{
+ NearestNeighbor,
+ ApproxBiLinear,
+ CatmullRom,
+ }
+ for _, q := range qs {
+ dst := image.NewRGBA(image.Rect(0, 0, 3, 1))
+ Copy(dst, image.Point{}, blue, dst.Bounds(), Src, nil)
+ q.Scale(dst, dst.Bounds(), red, red.Bounds(), Over, &Options{
+ DstMask: dstMask,
+ DstMaskP: image.Point{20, 0},
+ })
+ got := [3]color.RGBA{
+ dst.RGBAAt(0, 0),
+ dst.RGBAAt(1, 0),
+ dst.RGBAAt(2, 0),
+ }
+ want := [3]color.RGBA{
+ {0xff, 0x00, 0x00, 0xff},
+ {0x3f, 0x00, 0xc0, 0xff},
+ {0x00, 0x00, 0xff, 0xff},
+ }
+ if got != want {
+ t.Errorf("q=%T:\ngot %v\nwant %v", q, got, want)
+ }
+ }
+}
+
+func TestRectDstMask(t *testing.T) {
+ f, err := os.Open("../testdata/testpattern.png")
+ if err != nil {
+ t.Fatalf("Open: %v", err)
+ }
+ defer f.Close()
+ src, _, err := image.Decode(f)
+ if err != nil {
+ t.Fatalf("Decode: %v", err)
+ }
+ m00 := transformMatrix(1, 0, 0)
+
+ bounds := image.Rect(0, 0, 50, 50)
+ dstOutside := image.NewRGBA(bounds)
+ for y := bounds.Min.Y; y < bounds.Max.Y; y++ {
+ for x := bounds.Min.X; x < bounds.Max.X; x++ {
+ dstOutside.SetRGBA(x, y, color.RGBA{uint8(5 * x), uint8(5 * y), 0x00, 0xff})
+ }
+ }
+
+ mk := func(q Transformer, dstMask image.Image, dstMaskP image.Point) *image.RGBA {
+ m := image.NewRGBA(bounds)
+ Copy(m, bounds.Min, dstOutside, bounds, Src, nil)
+ q.Transform(m, m00, src, src.Bounds(), Over, &Options{
+ DstMask: dstMask,
+ DstMaskP: dstMaskP,
+ })
+ return m
+ }
+
+ qs := []Interpolator{
+ NearestNeighbor,
+ ApproxBiLinear,
+ CatmullRom,
+ }
+ dstMaskPs := []image.Point{
+ {0, 0},
+ {5, 7},
+ {-3, 0},
+ }
+ rect := image.Rect(10, 10, 30, 40)
+ for _, q := range qs {
+ for _, dstMaskP := range dstMaskPs {
+ dstInside := mk(q, nil, image.Point{})
+ for _, wrap := range []bool{false, true} {
+ // TODO: replace "rectImage(rect)" with "rect" once Go 1.5 is
+ // released, where an image.Rectangle implements image.Image.
+ dstMask := image.Image(rectImage(rect))
+ if wrap {
+ dstMask = srcWrapper{dstMask}
+ }
+ dst := mk(q, dstMask, dstMaskP)
+
+ nError := 0
+ loop:
+ for y := bounds.Min.Y; y < bounds.Max.Y; y++ {
+ for x := bounds.Min.X; x < bounds.Max.X; x++ {
+ which := dstOutside
+ if (image.Point{x, y}).Add(dstMaskP).In(rect) {
+ which = dstInside
+ }
+ if got, want := dst.RGBAAt(x, y), which.RGBAAt(x, y); got != want {
+ if nError == 10 {
+ t.Errorf("q=%T dmp=%v wrap=%v: ...and more errors", q, dstMaskP, wrap)
+ break loop
+ }
+ nError++
+ t.Errorf("q=%T dmp=%v wrap=%v: x=%3d y=%3d: got %v, want %v",
+ q, dstMaskP, wrap, x, y, got, want)
+ }
+ }
+ }
+ }
+ }
+ }
+}
+
+// TODO: delete this wrapper type once Go 1.5 is released, where an
+// image.Rectangle implements image.Image.
+type rectImage image.Rectangle
+
+func (r rectImage) ColorModel() color.Model { return color.Alpha16Model }
+func (r rectImage) Bounds() image.Rectangle { return image.Rectangle(r) }
+func (r rectImage) At(x, y int) color.Color {
+ if (image.Point{x, y}).In(image.Rectangle(r)) {
+ return color.Opaque
+ }
+ return color.Transparent
+}
+
+// The fooWrapper types wrap the dst or src image to avoid triggering the
+// type-specific fast path implementations.
+type (
+ dstWrapper struct{ Image }
+ srcWrapper struct{ image.Image }
+)
+
+func srcGray(boundsHint image.Rectangle) (image.Image, error) {
+ m := image.NewGray(boundsHint)
+ fillPix(rand.New(rand.NewSource(0)), m.Pix)
+ return m, nil
+}
+
+func srcNRGBA(boundsHint image.Rectangle) (image.Image, error) {
+ m := image.NewNRGBA(boundsHint)
+ fillPix(rand.New(rand.NewSource(1)), m.Pix)
+ return m, nil
+}
+
+func srcRGBA(boundsHint image.Rectangle) (image.Image, error) {
+ m := image.NewRGBA(boundsHint)
+ fillPix(rand.New(rand.NewSource(2)), m.Pix)
+ // RGBA is alpha-premultiplied, so the R, G and B values should
+ // be <= the A values.
+ for i := 0; i < len(m.Pix); i += 4 {
+ m.Pix[i+0] = uint8(uint32(m.Pix[i+0]) * uint32(m.Pix[i+3]) / 0xff)
+ m.Pix[i+1] = uint8(uint32(m.Pix[i+1]) * uint32(m.Pix[i+3]) / 0xff)
+ m.Pix[i+2] = uint8(uint32(m.Pix[i+2]) * uint32(m.Pix[i+3]) / 0xff)
+ }
+ return m, nil
+}
+
+func srcUnif(boundsHint image.Rectangle) (image.Image, error) {
+ return image.NewUniform(color.RGBA64{0x1234, 0x5555, 0x9181, 0xbeef}), nil
+}
+
+func srcYCbCr(boundsHint image.Rectangle) (image.Image, error) {
+ m := image.NewYCbCr(boundsHint, image.YCbCrSubsampleRatio420)
+ fillPix(rand.New(rand.NewSource(3)), m.Y, m.Cb, m.Cr)
+ return m, nil
+}
+
+func srcLarge(boundsHint image.Rectangle) (image.Image, error) {
+ // 3072 x 2304 is over 7 million pixels at 4:3, comparable to a
+ // 2015 smart-phone camera's output.
+ return srcYCbCr(image.Rect(0, 0, 3072, 2304))
+}
+
+func srcTux(boundsHint image.Rectangle) (image.Image, error) {
+ // tux.png is a 386 x 395 image.
+ f, err := os.Open("../testdata/tux.png")
+ if err != nil {
+ return nil, fmt.Errorf("Open: %v", err)
+ }
+ defer f.Close()
+ src, err := png.Decode(f)
+ if err != nil {
+ return nil, fmt.Errorf("Decode: %v", err)
+ }
+ return src, nil
+}
+
+func benchScale(b *testing.B, w int, h int, op Op, srcf func(image.Rectangle) (image.Image, error), q Interpolator) {
+ dst := image.NewRGBA(image.Rect(0, 0, w, h))
+ src, err := srcf(image.Rect(0, 0, 1024, 768))
+ if err != nil {
+ b.Fatal(err)
+ }
+ dr, sr := dst.Bounds(), src.Bounds()
+ scaler := Scaler(q)
+ if n, ok := q.(interface {
+ NewScaler(int, int, int, int) Scaler
+ }); ok {
+ scaler = n.NewScaler(dr.Dx(), dr.Dy(), sr.Dx(), sr.Dy())
+ }
+
+ b.ReportAllocs()
+ b.ResetTimer()
+ for i := 0; i < b.N; i++ {
+ scaler.Scale(dst, dr, src, sr, op, nil)
+ }
+}
+
+func benchTform(b *testing.B, w int, h int, op Op, srcf func(image.Rectangle) (image.Image, error), q Interpolator) {
+ dst := image.NewRGBA(image.Rect(0, 0, w, h))
+ src, err := srcf(image.Rect(0, 0, 1024, 768))
+ if err != nil {
+ b.Fatal(err)
+ }
+ sr := src.Bounds()
+ m := transformMatrix(3.75, 40, 10)
+
+ b.ReportAllocs()
+ b.ResetTimer()
+ for i := 0; i < b.N; i++ {
+ q.Transform(dst, m, src, sr, op, nil)
+ }
+}
+
+func BenchmarkScaleNNLargeDown(b *testing.B) { benchScale(b, 200, 150, Src, srcLarge, NearestNeighbor) }
+func BenchmarkScaleABLargeDown(b *testing.B) { benchScale(b, 200, 150, Src, srcLarge, ApproxBiLinear) }
+func BenchmarkScaleBLLargeDown(b *testing.B) { benchScale(b, 200, 150, Src, srcLarge, BiLinear) }
+func BenchmarkScaleCRLargeDown(b *testing.B) { benchScale(b, 200, 150, Src, srcLarge, CatmullRom) }
+
+func BenchmarkScaleNNDown(b *testing.B) { benchScale(b, 120, 80, Src, srcTux, NearestNeighbor) }
+func BenchmarkScaleABDown(b *testing.B) { benchScale(b, 120, 80, Src, srcTux, ApproxBiLinear) }
+func BenchmarkScaleBLDown(b *testing.B) { benchScale(b, 120, 80, Src, srcTux, BiLinear) }
+func BenchmarkScaleCRDown(b *testing.B) { benchScale(b, 120, 80, Src, srcTux, CatmullRom) }
+
+func BenchmarkScaleNNUp(b *testing.B) { benchScale(b, 800, 600, Src, srcTux, NearestNeighbor) }
+func BenchmarkScaleABUp(b *testing.B) { benchScale(b, 800, 600, Src, srcTux, ApproxBiLinear) }
+func BenchmarkScaleBLUp(b *testing.B) { benchScale(b, 800, 600, Src, srcTux, BiLinear) }
+func BenchmarkScaleCRUp(b *testing.B) { benchScale(b, 800, 600, Src, srcTux, CatmullRom) }
+
+func BenchmarkScaleNNSrcRGBA(b *testing.B) { benchScale(b, 200, 150, Src, srcRGBA, NearestNeighbor) }
+func BenchmarkScaleNNSrcUnif(b *testing.B) { benchScale(b, 200, 150, Src, srcUnif, NearestNeighbor) }
+
+func BenchmarkScaleNNOverRGBA(b *testing.B) { benchScale(b, 200, 150, Over, srcRGBA, NearestNeighbor) }
+func BenchmarkScaleNNOverUnif(b *testing.B) { benchScale(b, 200, 150, Over, srcUnif, NearestNeighbor) }
+
+func BenchmarkTformNNSrcRGBA(b *testing.B) { benchTform(b, 200, 150, Src, srcRGBA, NearestNeighbor) }
+func BenchmarkTformNNSrcUnif(b *testing.B) { benchTform(b, 200, 150, Src, srcUnif, NearestNeighbor) }
+
+func BenchmarkTformNNOverRGBA(b *testing.B) { benchTform(b, 200, 150, Over, srcRGBA, NearestNeighbor) }
+func BenchmarkTformNNOverUnif(b *testing.B) { benchTform(b, 200, 150, Over, srcUnif, NearestNeighbor) }
+
+func BenchmarkScaleABSrcGray(b *testing.B) { benchScale(b, 200, 150, Src, srcGray, ApproxBiLinear) }
+func BenchmarkScaleABSrcNRGBA(b *testing.B) { benchScale(b, 200, 150, Src, srcNRGBA, ApproxBiLinear) }
+func BenchmarkScaleABSrcRGBA(b *testing.B) { benchScale(b, 200, 150, Src, srcRGBA, ApproxBiLinear) }
+func BenchmarkScaleABSrcYCbCr(b *testing.B) { benchScale(b, 200, 150, Src, srcYCbCr, ApproxBiLinear) }
+
+func BenchmarkScaleABOverGray(b *testing.B) { benchScale(b, 200, 150, Over, srcGray, ApproxBiLinear) }
+func BenchmarkScaleABOverNRGBA(b *testing.B) { benchScale(b, 200, 150, Over, srcNRGBA, ApproxBiLinear) }
+func BenchmarkScaleABOverRGBA(b *testing.B) { benchScale(b, 200, 150, Over, srcRGBA, ApproxBiLinear) }
+func BenchmarkScaleABOverYCbCr(b *testing.B) { benchScale(b, 200, 150, Over, srcYCbCr, ApproxBiLinear) }
+
+func BenchmarkTformABSrcGray(b *testing.B) { benchTform(b, 200, 150, Src, srcGray, ApproxBiLinear) }
+func BenchmarkTformABSrcNRGBA(b *testing.B) { benchTform(b, 200, 150, Src, srcNRGBA, ApproxBiLinear) }
+func BenchmarkTformABSrcRGBA(b *testing.B) { benchTform(b, 200, 150, Src, srcRGBA, ApproxBiLinear) }
+func BenchmarkTformABSrcYCbCr(b *testing.B) { benchTform(b, 200, 150, Src, srcYCbCr, ApproxBiLinear) }
+
+func BenchmarkTformABOverGray(b *testing.B) { benchTform(b, 200, 150, Over, srcGray, ApproxBiLinear) }
+func BenchmarkTformABOverNRGBA(b *testing.B) { benchTform(b, 200, 150, Over, srcNRGBA, ApproxBiLinear) }
+func BenchmarkTformABOverRGBA(b *testing.B) { benchTform(b, 200, 150, Over, srcRGBA, ApproxBiLinear) }
+func BenchmarkTformABOverYCbCr(b *testing.B) { benchTform(b, 200, 150, Over, srcYCbCr, ApproxBiLinear) }
+
+func BenchmarkScaleCRSrcGray(b *testing.B) { benchScale(b, 200, 150, Src, srcGray, CatmullRom) }
+func BenchmarkScaleCRSrcNRGBA(b *testing.B) { benchScale(b, 200, 150, Src, srcNRGBA, CatmullRom) }
+func BenchmarkScaleCRSrcRGBA(b *testing.B) { benchScale(b, 200, 150, Src, srcRGBA, CatmullRom) }
+func BenchmarkScaleCRSrcYCbCr(b *testing.B) { benchScale(b, 200, 150, Src, srcYCbCr, CatmullRom) }
+
+func BenchmarkScaleCROverGray(b *testing.B) { benchScale(b, 200, 150, Over, srcGray, CatmullRom) }
+func BenchmarkScaleCROverNRGBA(b *testing.B) { benchScale(b, 200, 150, Over, srcNRGBA, CatmullRom) }
+func BenchmarkScaleCROverRGBA(b *testing.B) { benchScale(b, 200, 150, Over, srcRGBA, CatmullRom) }
+func BenchmarkScaleCROverYCbCr(b *testing.B) { benchScale(b, 200, 150, Over, srcYCbCr, CatmullRom) }
+
+func BenchmarkTformCRSrcGray(b *testing.B) { benchTform(b, 200, 150, Src, srcGray, CatmullRom) }
+func BenchmarkTformCRSrcNRGBA(b *testing.B) { benchTform(b, 200, 150, Src, srcNRGBA, CatmullRom) }
+func BenchmarkTformCRSrcRGBA(b *testing.B) { benchTform(b, 200, 150, Src, srcRGBA, CatmullRom) }
+func BenchmarkTformCRSrcYCbCr(b *testing.B) { benchTform(b, 200, 150, Src, srcYCbCr, CatmullRom) }
+
+func BenchmarkTformCROverGray(b *testing.B) { benchTform(b, 200, 150, Over, srcGray, CatmullRom) }
+func BenchmarkTformCROverNRGBA(b *testing.B) { benchTform(b, 200, 150, Over, srcNRGBA, CatmullRom) }
+func BenchmarkTformCROverRGBA(b *testing.B) { benchTform(b, 200, 150, Over, srcRGBA, CatmullRom) }
+func BenchmarkTformCROverYCbCr(b *testing.B) { benchTform(b, 200, 150, Over, srcYCbCr, CatmullRom) }
generated by cgit v1.2.3-1-g7c22 (git 2.25.1) at 2024-06-13 14:51:51 +0000