Rename cleanup package to preproc, and add basic cmd version

1 files changed, 105 insertions, 0 deletions

diff --git a/preproc/wipesides_test.go b/preproc/wipesides_test.go
new file mode 100644
index 0000000..76151fb
--- /dev/null
+++ b/preproc/wipesides_test.go
@@ -0,0 +1,105 @@
+package preproc
+
+// TODO: add different pages as test cases
+// TODO: test non integral img version
+
+import (
+	"flag"
+	"fmt"
+	"image"
+	"image/draw"
+	"image/png"
+	"os"
+	"testing"
+
+	"rescribe.xyz/go.git/binarize"
+)
+
+var update = flag.Bool("update", false, "update golden files")
+
+func decode(s string) (*image.Gray, error) {
+	f, err := os.Open(s)
+	defer f.Close()
+	if err != nil {
+		return nil, err
+	}
+	img, err := png.Decode(f)
+	if err != nil {
+		return nil, err
+	}
+	b := img.Bounds()
+	gray := image.NewGray(image.Rect(0, 0, b.Dx(), b.Dy()))
+	draw.Draw(gray, b, img, b.Min, draw.Src)
+	return gray, nil
+}
+
+func imgsequal(img1 *image.Gray, img2 *image.Gray) bool {
+	b := img1.Bounds()
+	if !b.Eq(img2.Bounds()) {
+		return false
+	}
+	for y := b.Min.Y; y < b.Max.Y; y++ {
+		for x := b.Min.X; x < b.Max.X; x++ {
+			r0, g0, b0, a0 := img1.At(x, y).RGBA()
+			r1, g1, b1, a1 := img2.At(x, y).RGBA()
+			if r0 != r1 {
+				return false
+			}
+			if g0 != g1 {
+				return false
+			}
+			if b0 != b1 {
+				return false
+			}
+			if a0 != a1 {
+				return false
+			}
+		}
+	}
+	return true
+}
+
+func TestWipeSides(t *testing.T) {
+	cases := []struct {
+		name   string
+		orig   string
+		golden string
+		thresh float64
+		wsize  int
+	}{
+		{"integralwipesides", "testdata/pg1.png", "testdata/pg1_integralwipesides_t0.02_w5.png", 0.02, 5},
+		{"integralwipesides", "testdata/pg1.png", "testdata/pg1_integralwipesides_t0.05_w5.png", 0.05, 5},
+		{"integralwipesides", "testdata/pg1.png", "testdata/pg1_integralwipesides_t0.05_w25.png", 0.05, 25},
+	}
+
+	for _, c := range cases {
+		t.Run(fmt.Sprintf("%s_%0.2f_%d", c.name, c.thresh, 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)
+			}
+			integral := binarize.Integralimg(orig)
+			lowedge, highedge := Findedges(integral, c.wsize, c.thresh)
+			actual = Wipesides(orig, lowedge, highedge)
+			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("Processed %s differs to %s\n", c.orig, c.golden)
+			}
+		})
+	}
+}