diff --git a/ext/opencv/scalar.cpp b/ext/opencv/scalar.cpp
index 02a0860..e99e027 100644
--- a/ext/opencv/scalar.cpp
+++ b/ext/opencv/scalar.cpp
@@ -1,4 +1,5 @@
 // -*- mode: c++; coding: utf-8 -*-
+#include <sstream>
 #include "ruby.h"
 #include "opencv2/core.hpp"
 
@@ -43,6 +44,16 @@ namespace rubyopencv {
       return TypedData_Make_Struct(klass, cv::Scalar, &opencv_scalar_type, ptr);
     }
 
+    /*
+     * Creates a new Scalar.
+     *
+     * @overload new(v0 = 0, v1 = 0, v2 = 0, v3 = 0)
+     * @param v0 [Number] Value 0
+     * @param v1 [Number] Value 1
+     * @param v2 [Number] Value 2
+     * @param v3 [Number] Value 3
+     * @return [Scalar] +self+
+     */
     VALUE rb_initialize(int argc, VALUE *argv, VALUE self) {
       const int SIZE = 4;
       VALUE values[SIZE];
@@ -82,16 +93,17 @@ namespace rubyopencv {
      * @return [String] String representation of the scalar
      */
     VALUE rb_to_s(VALUE self) {
-      const int i = 6;
-      VALUE str[i];
-      str[0] = rb_str_new2("<%s: [%g,%g,%g,%g]>");
-      str[1] = rb_str_new2(rb_class2name(CLASS_OF(self)));
-      str[2] = rb_aref(self, INT2FIX(0));
-      str[3] = rb_aref(self, INT2FIX(1));
-      str[4] = rb_aref(self, INT2FIX(2));
-      str[5] = rb_aref(self, INT2FIX(3));
+      std::stringstream s;
+      cv::Scalar* selfptr = obj2scalar(self);
+      s << *selfptr;
 
-      return rb_f_sprintf(i, str);
+      VALUE param[3];
+      param[0] = rb_str_new2("#<%s:%s>");
+      param[1] = rb_str_new2(rb_class2name(CLASS_OF(self)));
+      param[2] = rb_str_new2(s.str().c_str());
+
+      int n = sizeof(param) / sizeof(param[0]);
+      return rb_f_sprintf(n, param);
     }
 
     /*
diff --git a/test/helper.rb b/test/helper.rb
index adf195d..000fcc7 100755
--- a/test/helper.rb
+++ b/test/helper.rb
@@ -16,6 +16,8 @@ class OpenCVTestCase < Test::Unit::TestCase
 
   DUMMY_OBJ = Digest::MD5.new # dummy object for argument type check test
 
+  alias original_assert_in_delta assert_in_delta
+
   def snap(*images)
     n = -1
     images.map! { |val|
@@ -66,7 +68,7 @@ class OpenCVTestCase < Test::Unit::TestCase
       0.upto(expected.cols - 1) { |c|
         0.upto(expected.channels - 1) { |i|
           msg = "Failed at #{actual.class.to_s}<depth=#{actual.depth},channels=#{actual.channels}>(#{r}, #{c})[#{i}]"
-          assert_in_delta(expected[r, c][i], actual[r, c][i], delta, msg)
+          original_assert_in_delta(expected[r, c][i], actual[r, c][i], delta, msg)
         }
       }
     }
@@ -84,5 +86,20 @@ class OpenCVTestCase < Test::Unit::TestCase
     }
     m
   end
+
+  def assert_in_delta(expected, actual, delta, msg = nil)
+    if expected.is_a? Scalar or actual.is_a? Scalar
+      expected = expected.to_a if expected.is_a? Scalar
+      actual = actual.to_a if actual.is_a? Scalar
+      assert_in_delta(expected, actual, delta, msg)
+    elsif expected.is_a? Array and actual.is_a? Array
+      assert_equal(expected.size, actual.size)
+      expected.zip(actual) { |e, a|
+        original_assert_in_delta(e, a, delta, msg)
+      }
+    else
+      original_assert_in_delta(expected, actual, delta, msg)
+    end
+  end
 end
 
diff --git a/test/test_scalar.rb b/test/test_scalar.rb
new file mode 100755
index 0000000..3b9c9e6
--- /dev/null
+++ b/test/test_scalar.rb
@@ -0,0 +1,61 @@
+#!/usr/bin/env ruby
+# -*- mode: ruby; coding: utf-8 -*-
+require 'test/unit'
+require 'opencv'
+require File.expand_path(File.dirname(__FILE__)) + '/helper'
+
+include OpenCV
+
+# Tests for OpenCV::Scalar
+class TestScalar < OpenCVTestCase
+  def test_initialize
+    s = Scalar.new
+    assert_in_delta([0, 0, 0, 0], s, 0.01)
+
+    s = Scalar.new(1.1)
+    assert_in_delta([1.1, 0, 0, 0], s, 0.01)
+
+    s = Scalar.new(1.1, 2.2)
+    assert_in_delta([1.1, 2.2, 0, 0], s, 0.01)
+
+    s = Scalar.new(1.1, 2.2, 3.3)
+    assert_in_delta([1.1, 2.2, 3.3, 0], s, 0.01)
+
+    s = Scalar.new(1.1, 2.2, 3.3, 4.4)
+    assert_in_delta([1.1, 2.2, 3.3, 4.4], s, 0.01)
+  end
+  
+  def test_aref
+    assert_in_delta([0, 0, 0, 0], Scalar.new, 0.01)
+    assert_in_delta([10, 20, 30, 40], Scalar.new(10, 20, 30, 40), 0.01)
+    assert_in_delta([0.1, 0.2, 0.3, 0.4], Scalar.new(0.1, 0.2, 0.3, 0.4), 0.01)
+  end
+
+  def test_aset
+    s = Scalar.new
+    [10, 20, 30, 40].each_with_index { |x, i|
+      s[i] = x
+    }
+    assert_in_delta([10, 20, 30, 40], s, 0.01)
+
+    s = Scalar.new
+    [0.1, 0.2, 0.3, 0.4].each_with_index { |x, i|
+      s[i] = x
+    }
+    assert_in_delta([0.1, 0.2, 0.3, 0.4], s, 0.01)
+  end
+
+  def test_to_s
+    assert_equal('#<OpenCV::Scalar:[10, 20, 30, 40]>', Scalar.new(10, 20, 30, 40).to_s)
+    assert_equal('#<OpenCV::Scalar:[0.1, 0.2, 0.3, 0.4]>', Scalar.new(0.1, 0.2, 0.3, 0.4).to_s)
+  end
+
+  def test_to_ary
+    [[10, 20, 30, 40], [0.1, 0.2, 0.3, 0.4]].each { |a|
+      s = Scalar.new(*a)
+      x = s.to_a # Alias
+      assert_equal(Array, x.class)
+      assert_in_delta(a, x, 0.01)
+    }
+  end
+end