initial commit

vendor/golang.org/x/image/tiff/writer_test.go

@@ -0,0 +1,95 @@
+// Copyright 2012 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 tiff
+
+import (
+	"bytes"
+	"image"
+	"io/ioutil"
+	"os"
+	"testing"
+)
+
+var roundtripTests = []struct {
+	filename string
+	opts     *Options
+}{
+	{"video-001.tiff", nil},
+	{"video-001-16bit.tiff", nil},
+	{"video-001-gray.tiff", nil},
+	{"video-001-gray-16bit.tiff", nil},
+	{"video-001-paletted.tiff", nil},
+	{"bw-packbits.tiff", nil},
+	{"video-001.tiff", &Options{Predictor: true}},
+	{"video-001.tiff", &Options{Compression: Deflate}},
+	{"video-001.tiff", &Options{Predictor: true, Compression: Deflate}},
+}
+
+func openImage(filename string) (image.Image, error) {
+	f, err := os.Open(testdataDir + filename)
+	if err != nil {
+		return nil, err
+	}
+	defer f.Close()
+	return Decode(f)
+}
+
+func TestRoundtrip(t *testing.T) {
+	for _, rt := range roundtripTests {
+		img, err := openImage(rt.filename)
+		if err != nil {
+			t.Fatal(err)
+		}
+		out := new(bytes.Buffer)
+		err = Encode(out, img, rt.opts)
+		if err != nil {
+			t.Fatal(err)
+		}
+
+		img2, err := Decode(&buffer{buf: out.Bytes()})
+		if err != nil {
+			t.Fatal(err)
+		}
+		compare(t, img, img2)
+	}
+}
+
+// TestRoundtrip2 tests that encoding and decoding an image whose
+// origin is not (0, 0) gives the same thing.
+func TestRoundtrip2(t *testing.T) {
+	m0 := image.NewRGBA(image.Rect(3, 4, 9, 8))
+	for i := range m0.Pix {
+		m0.Pix[i] = byte(i)
+	}
+	out := new(bytes.Buffer)
+	if err := Encode(out, m0, nil); err != nil {
+		t.Fatal(err)
+	}
+	m1, err := Decode(&buffer{buf: out.Bytes()})
+	if err != nil {
+		t.Fatal(err)
+	}
+	compare(t, m0, m1)
+}
+
+func benchmarkEncode(b *testing.B, name string, pixelSize int) {
+	img, err := openImage(name)
+	if err != nil {
+		b.Fatal(err)
+	}
+	s := img.Bounds().Size()
+	b.SetBytes(int64(s.X * s.Y * pixelSize))
+	b.ResetTimer()
+	for i := 0; i < b.N; i++ {
+		Encode(ioutil.Discard, img, nil)
+	}
+}
+
+func BenchmarkEncode(b *testing.B)         { benchmarkEncode(b, "video-001.tiff", 4) }
+func BenchmarkEncodePaletted(b *testing.B) { benchmarkEncode(b, "video-001-paletted.tiff", 1) }
+func BenchmarkEncodeGray(b *testing.B)     { benchmarkEncode(b, "video-001-gray.tiff", 1) }
+func BenchmarkEncodeGray16(b *testing.B)   { benchmarkEncode(b, "video-001-gray-16bit.tiff", 2) }
+func BenchmarkEncodeRGBA(b *testing.B)     { benchmarkEncode(b, "video-001.tiff", 4) }
+func BenchmarkEncodeRGBA64(b *testing.B)   { benchmarkEncode(b, "video-001-16bit.tiff", 8) }