Find and fix edge case in rectangular image

compress.go

@@ -25,11 +25,11 @@ func (q *quadTreeNode) prune(tolerance float64) {
 // stack recursion - essentially a DFS of sorts
 func (q *quadTreeNode) canPrune(parent *quadTreeNode, tolerance float64) bool {
 	if q.children[NE] == nil || q.children[NW] == nil || q.children[SE] == nil || q.children[SW] == nil { // leaf node
-		colorDist := CIE76(parent.color, q.color)
-		//colorDist := EuclidianDistance(parent.color, q.color)
+		//colorDist := CIE76(parent.color, q.color)
+		colorDist := EuclidianDistance(parent.color, q.color)
 
 		// can prune if the LAB CIE76 is under the Just Noticeable Difference threshold
-		return colorDist <= 2.3*10
+		return colorDist <= tolerance
 	}
 
 	return q.children[NE].canPrune(parent, tolerance) && q.children[NW].canPrune(parent, tolerance) && q.children[SE].canPrune(parent, tolerance) && q.children[SW].canPrune(parent, tolerance)

compress_test.go

@@ -62,8 +62,8 @@ func TestCompressModifiesQuadTreeObject(t *testing.T) {
 	}
 }
 
-func TestCompressQuadTree(t *testing.T) {
-	path := "./samples/jungle.jpg"
+func TestCompressImageQuadTree(t *testing.T) {
+	path := "./samples/batman.png"
 	regularOut := "./normal_out.png"
 	compressedPath := "./compressed_out.png"
 

convert_test.go

@@ -1,6 +1,7 @@
 package main
 
 import (
+	"image/color"
 	"testing"
 )
 
@@ -18,3 +19,38 @@ func TestCreateImageRoundTripThroughQuadTree(t *testing.T) {
 		t.Fatalf("Error when converting quadtree to image: %+v", err)
 	}
 }
+
+func TestCreateFakeImage(t *testing.T) {
+	outPath := "./fake_out.png"
+
+	qt := QuadTree{}
+
+	qnNE := quadTreeNode{}
+	qnNE.color = color.RGBA{R: 0, G: 0, B: 0, A: 255}
+
+	qnNW := quadTreeNode{}
+	qnNW.color = color.RGBA{R: 255, G: 0, B: 0, A: 255}
+
+	qnSE := quadTreeNode{}
+	qnSE.color = color.RGBA{R: 0, G: 255, B: 0, A: 255}
+
+	qnSW := quadTreeNode{}
+	qnSW.color = color.RGBA{R: 0, G: 0, B: 255, A: 255}
+
+	qn := quadTreeNode{}
+	qn.children[NE] = &qnNE
+	qn.children[NW] = &qnNW
+	qn.children[SE] = &qnSE
+	qn.children[SW] = &qnSW
+
+	qn.color = color.RGBA{R: 63, G: 63, B: 63, A: 255}
+
+	qt.root = &qn
+	qt.height = 10
+	qt.width = 10
+
+	err := qt.ConvertToImage(outPath)
+	if err != nil {
+		t.Fatalf("Error creating fake image '%s': %+v", outPath, err)
+	}
+}

quadtree.go

@@ -1,6 +1,7 @@
 package main
 
 import (
+	//"fmt"
 	"image"
 	colorlib "image/color"
 )
@@ -44,6 +45,17 @@ func BuildQuadTree(imageSource string) (*QuadTree, error) {
 }
 
 func buildQuadTree(img *image.Image, x, y, w, h int) *quadTreeNode {
+	//if w == 0 && h == 0 {
+	//	fmt.Printf("YOU THE MOTHERFUCKER\n")
+	//	return nil
+	//}
+	if w == 0 {
+		w = 1
+	}
+	if h == 0 {
+		h = 1
+	}
+
 	if w == 1 && h == 1 {
 		qn := newQuadTreeNode((*img).At(x, y))
 		return &qn