git clone https://git.lucas.co/go_mono.git
bmp/reader_test.go (2K)
1 // Copyright 2012 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 bmp
6
7 import (
8 "bytes"
9 "fmt"
10 "image"
11 "io"
12 "os"
13 "testing"
14
15 _ "image/png"
16 )
17
18 const testdataDir = "../testdata/"
19
20 func compare(img0, img1 image.Image) error {
21 b := img1.Bounds()
22 if !b.Eq(img0.Bounds()) {
23 return fmt.Errorf("wrong image size: want %s, got %s", img0.Bounds(), b)
24 }
25 for y := b.Min.Y; y < b.Max.Y; y++ {
26 for x := b.Min.X; x < b.Max.X; x++ {
27 c0 := img0.At(x, y)
28 c1 := img1.At(x, y)
29 r0, g0, b0, a0 := c0.RGBA()
30 r1, g1, b1, a1 := c1.RGBA()
31 if r0 != r1 || g0 != g1 || b0 != b1 || a0 != a1 {
32 return fmt.Errorf("pixel at (%d, %d) has wrong color: want %v, got %v", x, y, c0, c1)
33 }
34 }
35 }
36 return nil
37 }
38
39 // TestDecode tests that decoding a PNG image and a BMP image result in the
40 // same pixel data.
41 func TestDecode(t *testing.T) {
42 testCases := []string{
43 "colormap",
44 "colormap-0",
45 "colormap-251",
46 "video-001",
47 "yellow_rose-small",
48 "yellow_rose-small-v5",
49 "bmp_1bpp",
50 "bmp_4bpp",
51 "bmp_8bpp",
52 }
53
54 for _, tc := range testCases {
55 f0, err := os.Open(testdataDir + tc + ".png")
56 if err != nil {
57 t.Errorf("%s: Open PNG: %v", tc, err)
58 continue
59 }
60 defer f0.Close()
61 img0, _, err := image.Decode(f0)
62 if err != nil {
63 t.Errorf("%s: Decode PNG: %v", tc, err)
64 continue
65 }
66
67 f1, err := os.Open(testdataDir + tc + ".bmp")
68 if err != nil {
69 t.Errorf("%s: Open BMP: %v", tc, err)
70 continue
71 }
72 defer f1.Close()
73 img1, _, err := image.Decode(f1)
74 if err != nil {
75 t.Errorf("%s: Decode BMP: %v", tc, err)
76 continue
77 }
78
79 if err := compare(img0, img1); err != nil {
80 t.Errorf("%s: %v", tc, err)
81 continue
82 }
83 }
84 }
85
86 // TestEOF tests that decoding a BMP image returns io.ErrUnexpectedEOF
87 // when there are no headers or data is empty
88 func TestEOF(t *testing.T) {
89 _, err := Decode(bytes.NewReader(nil))
90 if err != io.ErrUnexpectedEOF {
91 t.Errorf("Error should be io.ErrUnexpectedEOF on nil but got %v", err)
92 }
93 }