Source file src/image/image_test.go

     1  // Copyright 2011 The Go Authors. All rights reserved.
     2  // Use of this source code is governed by a BSD-style
     3  // license that can be found in the LICENSE file.
     4  
     5  package image
     6  
     7  import (
     8  	"image/color"
     9  	"image/color/palette"
    10  	"testing"
    11  )
    12  
    13  type image interface {
    14  	Image
    15  	Opaque() bool
    16  	Set(int, int, color.Color)
    17  	SubImage(Rectangle) Image
    18  }
    19  
    20  func cmp(cm color.Model, c0, c1 color.Color) bool {
    21  	r0, g0, b0, a0 := cm.Convert(c0).RGBA()
    22  	r1, g1, b1, a1 := cm.Convert(c1).RGBA()
    23  	return r0 == r1 && g0 == g1 && b0 == b1 && a0 == a1
    24  }
    25  
    26  var testImages = []struct {
    27  	name  string
    28  	image func() image
    29  }{
    30  	{"rgba", func() image { return NewRGBA(Rect(0, 0, 10, 10)) }},
    31  	{"rgba64", func() image { return NewRGBA64(Rect(0, 0, 10, 10)) }},
    32  	{"nrgba", func() image { return NewNRGBA(Rect(0, 0, 10, 10)) }},
    33  	{"nrgba64", func() image { return NewNRGBA64(Rect(0, 0, 10, 10)) }},
    34  	{"alpha", func() image { return NewAlpha(Rect(0, 0, 10, 10)) }},
    35  	{"alpha16", func() image { return NewAlpha16(Rect(0, 0, 10, 10)) }},
    36  	{"gray", func() image { return NewGray(Rect(0, 0, 10, 10)) }},
    37  	{"gray16", func() image { return NewGray16(Rect(0, 0, 10, 10)) }},
    38  	{"paletted", func() image {
    39  		return NewPaletted(Rect(0, 0, 10, 10), color.Palette{
    40  			Transparent,
    41  			Opaque,
    42  		})
    43  	}},
    44  }
    45  
    46  func TestImage(t *testing.T) {
    47  	for _, tc := range testImages {
    48  		m := tc.image()
    49  		if !Rect(0, 0, 10, 10).Eq(m.Bounds()) {
    50  			t.Errorf("%T: want bounds %v, got %v", m, Rect(0, 0, 10, 10), m.Bounds())
    51  			continue
    52  		}
    53  		if !cmp(m.ColorModel(), Transparent, m.At(6, 3)) {
    54  			t.Errorf("%T: at (6, 3), want a zero color, got %v", m, m.At(6, 3))
    55  			continue
    56  		}
    57  		m.Set(6, 3, Opaque)
    58  		if !cmp(m.ColorModel(), Opaque, m.At(6, 3)) {
    59  			t.Errorf("%T: at (6, 3), want a non-zero color, got %v", m, m.At(6, 3))
    60  			continue
    61  		}
    62  		if !m.SubImage(Rect(6, 3, 7, 4)).(image).Opaque() {
    63  			t.Errorf("%T: at (6, 3) was not opaque", m)
    64  			continue
    65  		}
    66  		m = m.SubImage(Rect(3, 2, 9, 8)).(image)
    67  		if !Rect(3, 2, 9, 8).Eq(m.Bounds()) {
    68  			t.Errorf("%T: sub-image want bounds %v, got %v", m, Rect(3, 2, 9, 8), m.Bounds())
    69  			continue
    70  		}
    71  		if !cmp(m.ColorModel(), Opaque, m.At(6, 3)) {
    72  			t.Errorf("%T: sub-image at (6, 3), want a non-zero color, got %v", m, m.At(6, 3))
    73  			continue
    74  		}
    75  		if !cmp(m.ColorModel(), Transparent, m.At(3, 3)) {
    76  			t.Errorf("%T: sub-image at (3, 3), want a zero color, got %v", m, m.At(3, 3))
    77  			continue
    78  		}
    79  		m.Set(3, 3, Opaque)
    80  		if !cmp(m.ColorModel(), Opaque, m.At(3, 3)) {
    81  			t.Errorf("%T: sub-image at (3, 3), want a non-zero color, got %v", m, m.At(3, 3))
    82  			continue
    83  		}
    84  		// Test that taking an empty sub-image starting at a corner does not panic.
    85  		m.SubImage(Rect(0, 0, 0, 0))
    86  		m.SubImage(Rect(10, 0, 10, 0))
    87  		m.SubImage(Rect(0, 10, 0, 10))
    88  		m.SubImage(Rect(10, 10, 10, 10))
    89  	}
    90  }
    91  
    92  func TestNewXxxBadRectangle(t *testing.T) {
    93  	// call calls f(r) and reports whether it ran without panicking.
    94  	call := func(f func(Rectangle), r Rectangle) (ok bool) {
    95  		defer func() {
    96  			if recover() != nil {
    97  				ok = false
    98  			}
    99  		}()
   100  		f(r)
   101  		return true
   102  	}
   103  
   104  	testCases := []struct {
   105  		name string
   106  		f    func(Rectangle)
   107  	}{
   108  		{"RGBA", func(r Rectangle) { NewRGBA(r) }},
   109  		{"RGBA64", func(r Rectangle) { NewRGBA64(r) }},
   110  		{"NRGBA", func(r Rectangle) { NewNRGBA(r) }},
   111  		{"NRGBA64", func(r Rectangle) { NewNRGBA64(r) }},
   112  		{"Alpha", func(r Rectangle) { NewAlpha(r) }},
   113  		{"Alpha16", func(r Rectangle) { NewAlpha16(r) }},
   114  		{"Gray", func(r Rectangle) { NewGray(r) }},
   115  		{"Gray16", func(r Rectangle) { NewGray16(r) }},
   116  		{"CMYK", func(r Rectangle) { NewCMYK(r) }},
   117  		{"Paletted", func(r Rectangle) { NewPaletted(r, color.Palette{color.Black, color.White}) }},
   118  		{"YCbCr", func(r Rectangle) { NewYCbCr(r, YCbCrSubsampleRatio422) }},
   119  		{"NYCbCrA", func(r Rectangle) { NewNYCbCrA(r, YCbCrSubsampleRatio444) }},
   120  	}
   121  
   122  	for _, tc := range testCases {
   123  		// Calling NewXxx(r) should fail (panic, since NewXxx doesn't return an
   124  		// error) unless r's width and height are both non-negative.
   125  		for _, negDx := range []bool{false, true} {
   126  			for _, negDy := range []bool{false, true} {
   127  				r := Rectangle{
   128  					Min: Point{15, 28},
   129  					Max: Point{16, 29},
   130  				}
   131  				if negDx {
   132  					r.Max.X = 14
   133  				}
   134  				if negDy {
   135  					r.Max.Y = 27
   136  				}
   137  
   138  				got := call(tc.f, r)
   139  				want := !negDx && !negDy
   140  				if got != want {
   141  					t.Errorf("New%s: negDx=%t, negDy=%t: got %t, want %t",
   142  						tc.name, negDx, negDy, got, want)
   143  				}
   144  			}
   145  		}
   146  
   147  		// Passing a Rectangle whose width and height is MaxInt should also fail
   148  		// (panic), due to overflow.
   149  		{
   150  			zeroAsUint := uint(0)
   151  			maxUint := zeroAsUint - 1
   152  			maxInt := int(maxUint / 2)
   153  			got := call(tc.f, Rectangle{
   154  				Min: Point{0, 0},
   155  				Max: Point{maxInt, maxInt},
   156  			})
   157  			if got {
   158  				t.Errorf("New%s: overflow: got ok, want !ok", tc.name)
   159  			}
   160  		}
   161  	}
   162  }
   163  
   164  func Test16BitsPerColorChannel(t *testing.T) {
   165  	testColorModel := []color.Model{
   166  		color.RGBA64Model,
   167  		color.NRGBA64Model,
   168  		color.Alpha16Model,
   169  		color.Gray16Model,
   170  	}
   171  	for _, cm := range testColorModel {
   172  		c := cm.Convert(color.RGBA64{0x1234, 0x1234, 0x1234, 0x1234}) // Premultiplied alpha.
   173  		r, _, _, _ := c.RGBA()
   174  		if r != 0x1234 {
   175  			t.Errorf("%T: want red value 0x%04x got 0x%04x", c, 0x1234, r)
   176  			continue
   177  		}
   178  	}
   179  	testImage := []image{
   180  		NewRGBA64(Rect(0, 0, 10, 10)),
   181  		NewNRGBA64(Rect(0, 0, 10, 10)),
   182  		NewAlpha16(Rect(0, 0, 10, 10)),
   183  		NewGray16(Rect(0, 0, 10, 10)),
   184  	}
   185  	for _, m := range testImage {
   186  		m.Set(1, 2, color.NRGBA64{0xffff, 0xffff, 0xffff, 0x1357}) // Non-premultiplied alpha.
   187  		r, _, _, _ := m.At(1, 2).RGBA()
   188  		if r != 0x1357 {
   189  			t.Errorf("%T: want red value 0x%04x got 0x%04x", m, 0x1357, r)
   190  			continue
   191  		}
   192  	}
   193  }
   194  
   195  func TestRGBA64Image(t *testing.T) {
   196  	// memset sets every element of s to v.
   197  	memset := func(s []byte, v byte) {
   198  		for i := range s {
   199  			s[i] = v
   200  		}
   201  	}
   202  
   203  	r := Rect(0, 0, 3, 2)
   204  	testCases := []Image{
   205  		NewAlpha(r),
   206  		NewAlpha16(r),
   207  		NewCMYK(r),
   208  		NewGray(r),
   209  		NewGray16(r),
   210  		NewNRGBA(r),
   211  		NewNRGBA64(r),
   212  		NewNYCbCrA(r, YCbCrSubsampleRatio444),
   213  		NewPaletted(r, palette.Plan9),
   214  		NewRGBA(r),
   215  		NewRGBA64(r),
   216  		NewUniform(color.RGBA64{}),
   217  		NewYCbCr(r, YCbCrSubsampleRatio444),
   218  		r,
   219  	}
   220  	for _, tc := range testCases {
   221  		switch tc := tc.(type) {
   222  		// Most of the concrete image types in the testCases implement the
   223  		// draw.RGBA64Image interface: they have a SetRGBA64 method. We use an
   224  		// interface literal here, instead of importing "image/draw", to avoid
   225  		// an import cycle.
   226  		//
   227  		// The YCbCr and NYCbCrA types are special-cased. Chroma subsampling
   228  		// means that setting one pixel can modify neighboring pixels. They
   229  		// don't have Set or SetRGBA64 methods because that side effect could
   230  		// be surprising. Here, we just memset the channel buffers instead.
   231  		//
   232  		// The Uniform and Rectangle types are also special-cased, as they
   233  		// don't have a Set or SetRGBA64 method.
   234  		case interface {
   235  			SetRGBA64(x, y int, c color.RGBA64)
   236  		}:
   237  			tc.SetRGBA64(1, 1, color.RGBA64{0x7FFF, 0x3FFF, 0x0000, 0x7FFF})
   238  
   239  		case *NYCbCrA:
   240  			memset(tc.YCbCr.Y, 0x77)
   241  			memset(tc.YCbCr.Cb, 0x88)
   242  			memset(tc.YCbCr.Cr, 0x99)
   243  			memset(tc.A, 0xAA)
   244  
   245  		case *Uniform:
   246  			tc.C = color.RGBA64{0x7FFF, 0x3FFF, 0x0000, 0x7FFF}
   247  
   248  		case *YCbCr:
   249  			memset(tc.Y, 0x77)
   250  			memset(tc.Cb, 0x88)
   251  			memset(tc.Cr, 0x99)
   252  
   253  		case Rectangle:
   254  			// No-op. Rectangle pixels' colors are immutable. They're always
   255  			// color.Opaque.
   256  
   257  		default:
   258  			t.Errorf("could not initialize pixels for %T", tc)
   259  			continue
   260  		}
   261  
   262  		// Check that RGBA64At(x, y) is equivalent to At(x, y).RGBA().
   263  		rgba64Image, ok := tc.(RGBA64Image)
   264  		if !ok {
   265  			t.Errorf("%T is not an RGBA64Image", tc)
   266  			continue
   267  		}
   268  		got := rgba64Image.RGBA64At(1, 1)
   269  		wantR, wantG, wantB, wantA := tc.At(1, 1).RGBA()
   270  		if (uint32(got.R) != wantR) || (uint32(got.G) != wantG) ||
   271  			(uint32(got.B) != wantB) || (uint32(got.A) != wantA) {
   272  			t.Errorf("%T:\ngot  (0x%04X, 0x%04X, 0x%04X, 0x%04X)\n"+
   273  				"want (0x%04X, 0x%04X, 0x%04X, 0x%04X)", tc,
   274  				got.R, got.G, got.B, got.A,
   275  				wantR, wantG, wantB, wantA)
   276  			continue
   277  		}
   278  	}
   279  }
   280  
   281  func BenchmarkAt(b *testing.B) {
   282  	for _, tc := range testImages {
   283  		b.Run(tc.name, func(b *testing.B) {
   284  			m := tc.image()
   285  			b.ReportAllocs()
   286  			b.ResetTimer()
   287  			for i := 0; i < b.N; i++ {
   288  				m.At(4, 5)
   289  			}
   290  		})
   291  	}
   292  }
   293  
   294  func BenchmarkSet(b *testing.B) {
   295  	c := color.Gray{0xff}
   296  	for _, tc := range testImages {
   297  		b.Run(tc.name, func(b *testing.B) {
   298  			m := tc.image()
   299  			b.ReportAllocs()
   300  			b.ResetTimer()
   301  			for i := 0; i < b.N; i++ {
   302  				m.Set(4, 5, c)
   303  			}
   304  		})
   305  	}
   306  }
   307  
   308  func BenchmarkRGBAAt(b *testing.B) {
   309  	m := NewRGBA(Rect(0, 0, 10, 10))
   310  	b.ResetTimer()
   311  
   312  	for i := 0; i < b.N; i++ {
   313  		m.RGBAAt(4, 5)
   314  	}
   315  }
   316  
   317  func BenchmarkRGBASetRGBA(b *testing.B) {
   318  	m := NewRGBA(Rect(0, 0, 10, 10))
   319  	c := color.RGBA{0xff, 0xff, 0xff, 0x13}
   320  	b.ResetTimer()
   321  
   322  	for i := 0; i < b.N; i++ {
   323  		m.SetRGBA(4, 5, c)
   324  	}
   325  }
   326  
   327  func BenchmarkRGBA64At(b *testing.B) {
   328  	m := NewRGBA64(Rect(0, 0, 10, 10))
   329  	b.ResetTimer()
   330  
   331  	for i := 0; i < b.N; i++ {
   332  		m.RGBA64At(4, 5)
   333  	}
   334  }
   335  
   336  func BenchmarkRGBA64SetRGBA64(b *testing.B) {
   337  	m := NewRGBA64(Rect(0, 0, 10, 10))
   338  	c := color.RGBA64{0xffff, 0xffff, 0xffff, 0x1357}
   339  	b.ResetTimer()
   340  
   341  	for i := 0; i < b.N; i++ {
   342  		m.SetRGBA64(4, 5, c)
   343  	}
   344  }
   345  
   346  func BenchmarkNRGBAAt(b *testing.B) {
   347  	m := NewNRGBA(Rect(0, 0, 10, 10))
   348  	b.ResetTimer()
   349  
   350  	for i := 0; i < b.N; i++ {
   351  		m.NRGBAAt(4, 5)
   352  	}
   353  }
   354  
   355  func BenchmarkNRGBASetNRGBA(b *testing.B) {
   356  	m := NewNRGBA(Rect(0, 0, 10, 10))
   357  	c := color.NRGBA{0xff, 0xff, 0xff, 0x13}
   358  	b.ResetTimer()
   359  
   360  	for i := 0; i < b.N; i++ {
   361  		m.SetNRGBA(4, 5, c)
   362  	}
   363  }
   364  
   365  func BenchmarkNRGBA64At(b *testing.B) {
   366  	m := NewNRGBA64(Rect(0, 0, 10, 10))
   367  	b.ResetTimer()
   368  
   369  	for i := 0; i < b.N; i++ {
   370  		m.NRGBA64At(4, 5)
   371  	}
   372  }
   373  
   374  func BenchmarkNRGBA64SetNRGBA64(b *testing.B) {
   375  	m := NewNRGBA64(Rect(0, 0, 10, 10))
   376  	c := color.NRGBA64{0xffff, 0xffff, 0xffff, 0x1357}
   377  	b.ResetTimer()
   378  
   379  	for i := 0; i < b.N; i++ {
   380  		m.SetNRGBA64(4, 5, c)
   381  	}
   382  }
   383  
   384  func BenchmarkAlphaAt(b *testing.B) {
   385  	m := NewAlpha(Rect(0, 0, 10, 10))
   386  	b.ResetTimer()
   387  
   388  	for i := 0; i < b.N; i++ {
   389  		m.AlphaAt(4, 5)
   390  	}
   391  }
   392  
   393  func BenchmarkAlphaSetAlpha(b *testing.B) {
   394  	m := NewAlpha(Rect(0, 0, 10, 10))
   395  	c := color.Alpha{0x13}
   396  	b.ResetTimer()
   397  
   398  	for i := 0; i < b.N; i++ {
   399  		m.SetAlpha(4, 5, c)
   400  	}
   401  }
   402  
   403  func BenchmarkAlpha16At(b *testing.B) {
   404  	m := NewAlpha16(Rect(0, 0, 10, 10))
   405  	b.ResetTimer()
   406  
   407  	for i := 0; i < b.N; i++ {
   408  		m.Alpha16At(4, 5)
   409  	}
   410  }
   411  
   412  func BenchmarkAlphaSetAlpha16(b *testing.B) {
   413  	m := NewAlpha16(Rect(0, 0, 10, 10))
   414  	c := color.Alpha16{0x13}
   415  	b.ResetTimer()
   416  
   417  	for i := 0; i < b.N; i++ {
   418  		m.SetAlpha16(4, 5, c)
   419  	}
   420  }
   421  
   422  func BenchmarkGrayAt(b *testing.B) {
   423  	m := NewGray(Rect(0, 0, 10, 10))
   424  	b.ResetTimer()
   425  
   426  	for i := 0; i < b.N; i++ {
   427  		m.GrayAt(4, 5)
   428  	}
   429  }
   430  
   431  func BenchmarkGraySetGray(b *testing.B) {
   432  	m := NewGray(Rect(0, 0, 10, 10))
   433  	c := color.Gray{0x13}
   434  	b.ResetTimer()
   435  
   436  	for i := 0; i < b.N; i++ {
   437  		m.SetGray(4, 5, c)
   438  	}
   439  }
   440  
   441  func BenchmarkGray16At(b *testing.B) {
   442  	m := NewGray16(Rect(0, 0, 10, 10))
   443  	b.ResetTimer()
   444  
   445  	for i := 0; i < b.N; i++ {
   446  		m.Gray16At(4, 5)
   447  	}
   448  }
   449  
   450  func BenchmarkGraySetGray16(b *testing.B) {
   451  	m := NewGray16(Rect(0, 0, 10, 10))
   452  	c := color.Gray16{0x13}
   453  	b.ResetTimer()
   454  
   455  	for i := 0; i < b.N; i++ {
   456  		m.SetGray16(4, 5, c)
   457  	}
   458  }
   459  

View as plain text