package preproc import ( "flag" "fmt" "image" "image/png" "os" "testing" ) func TestBinarization(t *testing.T) { var slow = flag.Bool("slow", false, "include slow tests") var update = flag.Bool("updatesauvola", false, "update golden files") cases := []struct { name string orig string golden string ksize float64 wsize int }{ {"integralsauvola", "testdata/pg1.png", "testdata/pg1_integralsauvola_k0.5_w41.png", 0.5, 41}, {"integralsauvola", "testdata/pg1.png", "testdata/pg1_integralsauvola_k0.5_w19.png", 0.5, 19}, {"integralsauvola", "testdata/pg1.png", "testdata/pg1_integralsauvola_k0.3_w19.png", 0.3, 19}, {"sauvola", "testdata/pg1.png", "testdata/pg1_sauvola_k0.5_w41.png", 0.5, 41}, {"sauvola", "testdata/pg1.png", "testdata/pg1_sauvola_k0.5_w19.png", 0.5, 19}, {"sauvola", "testdata/pg1.png", "testdata/pg1_sauvola_k0.3_w19.png", 0.3, 19}, } for _, c := range cases { t.Run(fmt.Sprintf("%s_%0.1f_%d", c.name, c.ksize, c.wsize), func(t *testing.T) { var actual *image.Gray orig, err := decode(c.orig) if err != nil { t.Fatalf("Could not open file %s: %v\n", c.orig, err) } switch c.name { case "integralsauvola": actual = IntegralSauvola(orig, c.ksize, c.wsize) case "sauvola": if *slow { actual = Sauvola(orig, c.ksize, c.wsize) } else { t.Skip("Skipping slow test; use -slow to run it.\n") } default: t.Fatalf("No method %s\n", c.name) } if *update { f, err := os.Create(c.golden) defer f.Close() if err != nil { t.Fatalf("Could not open file %s to update: %v\n", c.golden, err) } err = png.Encode(f, actual) if err != nil { t.Fatalf("Could not encode update of %s: %v\n", c.golden, err) } } golden, err := decode(c.golden) if err != nil { t.Fatalf("Could not open file %s: %v\n", c.golden, err) } if !imgsequal(golden, actual) { t.Errorf("Binarized %s differs to %s\n", c.orig, c.golden) } }) } }