diff options
Diffstat (limited to 'src/pkg/image/png/writer_test.go')
-rw-r--r-- | src/pkg/image/png/writer_test.go | 149 |
1 files changed, 149 insertions, 0 deletions
diff --git a/src/pkg/image/png/writer_test.go b/src/pkg/image/png/writer_test.go new file mode 100644 index 000000000..1599791b3 --- /dev/null +++ b/src/pkg/image/png/writer_test.go @@ -0,0 +1,149 @@ +// Copyright 2009 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 png + +import ( + "bytes" + "fmt" + "image" + "io/ioutil" + "os" + "testing" +) + +func diff(m0, m1 image.Image) os.Error { + b0, b1 := m0.Bounds(), m1.Bounds() + if !b0.Size().Eq(b1.Size()) { + return fmt.Errorf("dimensions differ: %v vs %v", b0, b1) + } + dx := b1.Min.X - b0.Min.X + dy := b1.Min.Y - b0.Min.Y + for y := b0.Min.Y; y < b0.Max.Y; y++ { + for x := b0.Min.X; x < b0.Max.X; x++ { + c0 := m0.At(x, y) + c1 := m1.At(x+dx, y+dy) + r0, g0, b0, a0 := c0.RGBA() + r1, g1, b1, a1 := c1.RGBA() + if r0 != r1 || g0 != g1 || b0 != b1 || a0 != a1 { + return fmt.Errorf("colors differ at (%d, %d): %v vs %v", x, y, c0, c1) + } + } + } + return nil +} + +func encodeDecode(m image.Image) (image.Image, os.Error) { + b := bytes.NewBuffer(nil) + err := Encode(b, m) + if err != nil { + return nil, err + } + m, err = Decode(b) + if err != nil { + return nil, err + } + return m, nil +} + +func TestWriter(t *testing.T) { + // The filenames variable is declared in reader_test.go. + names := filenames + if testing.Short() { + names = filenamesShort + } + for _, fn := range names { + qfn := "testdata/pngsuite/" + fn + ".png" + // Read the image. + m0, err := readPng(qfn) + if err != nil { + t.Error(fn, err) + continue + } + // Read the image again, encode it, and decode it. + m1, err := readPng(qfn) + if err != nil { + t.Error(fn, err) + return + } + m2, err := encodeDecode(m1) + if err != nil { + t.Error(fn, err) + return + } + // Compare the two. + err = diff(m0, m2) + if err != nil { + t.Error(fn, err) + continue + } + } +} + +func TestSubImage(t *testing.T) { + m0 := image.NewRGBA(256, 256) + for y := 0; y < 256; y++ { + for x := 0; x < 256; x++ { + m0.Set(x, y, image.RGBAColor{uint8(x), uint8(y), 0, 255}) + } + } + m0 = m0.SubImage(image.Rect(50, 30, 250, 130)).(*image.RGBA) + m1, err := encodeDecode(m0) + if err != nil { + t.Error(err) + return + } + err = diff(m0, m1) + if err != nil { + t.Error(err) + return + } +} + +func BenchmarkEncodePaletted(b *testing.B) { + b.StopTimer() + img := image.NewPaletted(640, 480, + []image.Color{ + image.RGBAColor{0, 0, 0, 255}, + image.RGBAColor{255, 255, 255, 255}, + }) + b.SetBytes(640 * 480 * 1) + b.StartTimer() + for i := 0; i < b.N; i++ { + Encode(ioutil.Discard, img) + } +} + +func BenchmarkEncodeRGBOpaque(b *testing.B) { + b.StopTimer() + img := image.NewRGBA(640, 480) + // Set all pixels to 0xFF alpha to force opaque mode. + bo := img.Bounds() + for y := bo.Min.Y; y < bo.Max.Y; y++ { + for x := bo.Min.X; x < bo.Max.X; x++ { + img.Set(x, y, image.RGBAColor{0, 0, 0, 255}) + } + } + if !img.Opaque() { + panic("expected image to be opaque") + } + b.SetBytes(640 * 480 * 4) + b.StartTimer() + for i := 0; i < b.N; i++ { + Encode(ioutil.Discard, img) + } +} + +func BenchmarkEncodeRGBA(b *testing.B) { + b.StopTimer() + img := image.NewRGBA(640, 480) + if img.Opaque() { + panic("expected image to not be opaque") + } + b.SetBytes(640 * 480 * 4) + b.StartTimer() + for i := 0; i < b.N; i++ { + Encode(ioutil.Discard, img) + } +} |