diff --git a/converter_test.go b/converter_test.go
new file mode 100644
index 0000000..85639ef
--- /dev/null
+++ b/converter_test.go
@@ -0,0 +1,43 @@
+package resize
+
+import (
+	"testing"
+)
+
+func Test_ClampUint8(t *testing.T) {
+	var testData = []struct {
+		in       int32
+		expected uint8
+	}{
+		{0, 0},
+		{255, 255},
+		{128, 128},
+		{-2, 0},
+		{256, 255},
+	}
+	for _, test := range testData {
+		actual := clampUint8(test.in)
+		if actual != test.expected {
+			t.Fail()
+		}
+	}
+}
+
+func Test_ClampUint16(t *testing.T) {
+	var testData = []struct {
+		in       int64
+		expected uint16
+	}{
+		{0, 0},
+		{65535, 65535},
+		{128, 128},
+		{-2, 0},
+		{65536, 65535},
+	}
+	for _, test := range testData {
+		actual := clampUint16(test.in)
+		if actual != test.expected {
+			t.Fail()
+		}
+	}
+}