diff --git a/ext/opencv/mouseevent.cpp b/ext/opencv/mouseevent.cpp
index 1519003..ea57f9e 100644
--- a/ext/opencv/mouseevent.cpp
+++ b/ext/opencv/mouseevent.cpp
@@ -117,7 +117,7 @@ VALUE rb_event(VALUE self)
 VALUE
 rb_left_button_q(VALUE self)
 {
-  return MOUSEEVENT(self)->flag & CV_EVENT_FLAG_LBUTTON ? Qtrue : Qfalse;
+  return MOUSEEVENT(self)->flags & CV_EVENT_FLAG_LBUTTON ? Qtrue : Qfalse;
 }
 
 /*
@@ -126,7 +126,7 @@ rb_left_button_q(VALUE self)
 VALUE
 rb_right_button_q(VALUE self)
 {
-  return MOUSEEVENT(self)->flag & CV_EVENT_FLAG_RBUTTON ? Qtrue : Qfalse;
+  return MOUSEEVENT(self)->flags & CV_EVENT_FLAG_RBUTTON ? Qtrue : Qfalse;
 }
 
 /*
@@ -135,7 +135,7 @@ rb_right_button_q(VALUE self)
 VALUE
 rb_middle_button_q(VALUE self)
 {
-  return MOUSEEVENT(self)->flag & CV_EVENT_FLAG_MBUTTON ? Qtrue : Qfalse;
+  return MOUSEEVENT(self)->flags & CV_EVENT_FLAG_MBUTTON ? Qtrue : Qfalse;
 }
 
 /*
@@ -144,7 +144,7 @@ rb_middle_button_q(VALUE self)
 VALUE
 rb_ctrl_key_q(VALUE self)
 {
-  return MOUSEEVENT(self)->flag & CV_EVENT_FLAG_CTRLKEY ? Qtrue : Qfalse;
+  return MOUSEEVENT(self)->flags & CV_EVENT_FLAG_CTRLKEY ? Qtrue : Qfalse;
 }
 
 /*
@@ -153,7 +153,7 @@ rb_ctrl_key_q(VALUE self)
 VALUE
 rb_shift_key_q(VALUE self)
 {
-  return MOUSEEVENT(self)->flag & CV_EVENT_FLAG_SHIFTKEY ? Qtrue : Qfalse;
+  return MOUSEEVENT(self)->flags & CV_EVENT_FLAG_SHIFTKEY ? Qtrue : Qfalse;
 }
 
 /*
@@ -162,18 +162,18 @@ rb_shift_key_q(VALUE self)
 VALUE
 rb_alt_key_q(VALUE self)
 {
-  return MOUSEEVENT(self)->flag & CV_EVENT_FLAG_ALTKEY ? Qtrue : Qfalse;
+  return MOUSEEVENT(self)->flags & CV_EVENT_FLAG_ALTKEY ? Qtrue : Qfalse;
 }
 
 VALUE
-new_object(int flag, int y, int x, int event)
+new_object(int event, int x, int y, int flags)
 {
   VALUE object = rb_allocate(rb_class());
   MouseEvent *mouseevent = MOUSEEVENT(object);
   mouseevent->point.x = x;
   mouseevent->point.y = y;
   mouseevent->event = event;
-  mouseevent->flag = flag;
+  mouseevent->flags = flags;
   return object;
 }
 
diff --git a/ext/opencv/mouseevent.h b/ext/opencv/mouseevent.h
index fc532c7..260cba5 100644
--- a/ext/opencv/mouseevent.h
+++ b/ext/opencv/mouseevent.h
@@ -24,7 +24,7 @@ __NAMESPACE_BEGIN_MOUSEEVENT
 typedef struct MouseEvent {
   CvPoint point;
   int event;
-  int flag;
+  int flags;
 } MouseEvent;
 
 VALUE rb_class();
diff --git a/ext/opencv/opencv.cpp b/ext/opencv/opencv.cpp
index baad070..37d2489 100644
--- a/ext/opencv/opencv.cpp
+++ b/ext/opencv/opencv.cpp
@@ -409,6 +409,9 @@ define_ruby_module()
   rb_define_const(rb_module, "CV_FM_8POINT", INT2FIX(CV_FM_8POINT));
   rb_define_const(rb_module, "CV_FM_RANSAC", INT2FIX(CV_FM_RANSAC));
   rb_define_const(rb_module, "CV_FM_LMEDS", INT2FIX(CV_FM_LMEDS));
+
+  /* Flags of window */
+  rb_define_const(rb_module, "CV_WINDOW_AUTOSIZE", INT2FIX(CV_WINDOW_AUTOSIZE));
   
   VALUE inversion_method = rb_hash_new();
   /* {:lu, :svd, :svd_sym(:svd_symmetric)}: Inversion method */
diff --git a/ext/opencv/window.cpp b/ext/opencv/window.cpp
index cff0ae8..115b73c 100644
--- a/ext/opencv/window.cpp
+++ b/ext/opencv/window.cpp
@@ -30,8 +30,7 @@ GET_WINDOW_NAME(VALUE object)
   void *handle = DATA_PTR(object);
   if (!handle)
     rb_raise(rb_eStandardError, "window handle error"); 
-  const char *window_name = cvGetWindowName(handle);
-  return window_name;
+  return (const char*)cvGetWindowName(handle);
 }
 
 st_table *windows = st_init_numtable();
@@ -64,10 +63,10 @@ define_ruby_class()
   rb_define_singleton_method(rb_klass, "destroy_all", RUBY_METHOD_FUNC(rb_destroy_all), 0);
   rb_define_method(rb_klass, "resize", RUBY_METHOD_FUNC(rb_resize), -1);
   rb_define_method(rb_klass, "move", RUBY_METHOD_FUNC(rb_move), -1);
-  rb_define_method(rb_klass, "show_image", RUBY_METHOD_FUNC(rb_show_image), 1);
+  rb_define_method(rb_klass, "show_image", RUBY_METHOD_FUNC(rb_show_image), -1);
   rb_define_alias(rb_klass, "show", "show_image");
   rb_define_method(rb_klass, "set_trackbar", RUBY_METHOD_FUNC(rb_set_trackbar), -1);
-  rb_define_method(rb_klass, "set_mouse_callback", RUBY_METHOD_FUNC(rb_set_mouse_callback), 0);
+  rb_define_method(rb_klass, "set_mouse_callback", RUBY_METHOD_FUNC(rb_set_mouse_callback), -1);
   rb_define_alias(rb_klass, "on_mouse", "set_mouse_callback");
 }
 
@@ -121,34 +120,26 @@ rb_aref(VALUE klass, VALUE name)
 
 /*
  * call-seq:
- *   new(<i>name[,autosize]</i>)
+ *   new(<i>name[,flags]</i>)
  *
  * Create new window named <i>name</i>.
- * If <i>autoresize</i> is true(default), window size automatically resize when image given.
+ * If <i>flags</i> is CV_WINDOW_AUTOSIZE (default), window size automatically resize when image given.
  */
 VALUE
 rb_initialize(int argc, VALUE *argv, VALUE self)
 {
-  VALUE name, autosize;
-  rb_scan_args(argc, argv, "11", &name, &autosize);
+  VALUE name, flags;
+  rb_scan_args(argc, argv, "11", &name, &flags);
   Check_Type(name, T_STRING);
-  int mode;
-  if (argc < 2)
-    mode = CV_WINDOW_AUTOSIZE;
-  else{
-    switch (TYPE(autosize)) {
-    case T_TRUE:
-      mode = CV_WINDOW_AUTOSIZE;
-      break;
-    case T_FALSE:
-      mode = 0;
-      break;
-    default:
-      rb_raise(rb_eTypeError, "argument 2 (auto-size) should be true or false.");
-    }
+  int mode = CV_WINDOW_AUTOSIZE;
+  if (argc == 2) {
+    Check_Type(flags, T_FIXNUM);
+    mode = FIX2INT(flags);
   }
-  cvNamedWindow(StringValueCStr(name), mode);
-  void *handle = cvGetWindowHandle(StringValueCStr(name));
+
+  char* name_str = StringValueCStr(name);
+  cvNamedWindow(name_str, mode);
+  void *handle = cvGetWindowHandle(name_str);
   if (st_lookup(windows, (st_data_t)handle, 0)) {
     rb_raise(rb_eStandardError, "window name should be unique.");
   }
@@ -217,7 +208,8 @@ rb_resize(int argc, VALUE *argv, VALUE self)
     size = cvSize(FIX2INT(argv[0]), FIX2INT(argv[1]));
     break;
   default:
-    rb_raise(rb_eArgError, "wrong number of arguments (1 or 2)");          
+    rb_raise(rb_eArgError, "wrong number of arguments (1 or 2)");
+    break;
   }
   cvResizeWindow(GET_WINDOW_NAME(self), size.width, size.height);
   return self;
@@ -242,7 +234,8 @@ rb_move(int argc, VALUE *argv, VALUE self)
     point = cvPoint(FIX2INT(argv[0]), FIX2INT(argv[1]));
     break;
   default:
-    rb_raise(rb_eArgError, "wrong number of arguments (1 or 2)");          
+    rb_raise(rb_eArgError, "wrong number of arguments (1 or 2)");
+    break;
   }
   cvMoveWindow(GET_WINDOW_NAME(self), point.x, point.y);
   return self;
@@ -252,22 +245,27 @@ rb_move(int argc, VALUE *argv, VALUE self)
  * call-seq:
  *   show_image(<i>image</i>)
  *
- * Show the image. If the window was created with <i>autosize</i> = true then the image is shown
+ * Show the image. If the window was created with <i>flags</i> = CV_WINDOW_AUTOSIZE then the image is shown
  * with its original size, otherwize the image is scaled to fit the window.
  */
 VALUE
-rb_show_image(VALUE self, VALUE image)
+rb_show_image(int argc, VALUE *argv, VALUE self)
 {
-  if (!rb_obj_is_kind_of(image, cCvMat::rb_class())) {
-    rb_raise(rb_eTypeError, "argument should be %s.", rb_class2name(cCvMat::rb_class()));
+  CvArr* image = NULL;
+  if (argc > 0) {
+    if (!rb_obj_is_kind_of(argv[0], cCvMat::rb_class()))
+      rb_raise(rb_eTypeError, "argument should be %s.", rb_class2name(cCvMat::rb_class()));
+    else
+      image = CVARR(argv[0]);
+
+    st_table *holder;
+    if (st_lookup(windows, (st_data_t)DATA_PTR(self), (st_data_t*)&holder)) {
+      st_insert(holder, cCvMat::rb_class(), argv[0]);
+    }else
+      rb_raise(rb_eFatal, "invalid window operation.");
   }
-  cvShowImage(GET_WINDOW_NAME(self), CVARR(image));
-  st_table *holder;
-  if (st_lookup(windows, (st_data_t)DATA_PTR(self), (st_data_t*)&holder)) {
-    st_insert(holder, cCvMat::rb_class(), image);
-    return self;
-  }else
-    rb_raise(rb_eFatal, "invalid window operation.");
+  cvShowImage(GET_WINDOW_NAME(self), image);
+  
   return self;
 }
 
@@ -291,7 +289,8 @@ rb_set_trackbar(int argc, VALUE *argv, VALUE self)
   }
   Trackbar *trackbar = TRACKBAR(instance);
   void *callback = (void *)alloc_callback(&trackbar_callback, trackbar->block);
-  cvCreateTrackbar(trackbar->name, GET_WINDOW_NAME(self), &trackbar->val, trackbar->maxval, (CvTrackbarCallback)callback);
+  cvCreateTrackbar(trackbar->name, GET_WINDOW_NAME(self), &(trackbar->val), trackbar->maxval,
+		   (CvTrackbarCallback)callback);
   st_table *holder;
   if (st_lookup(windows, (st_data_t)DATA_PTR(self), (st_data_t*)&holder)) {
     st_insert(holder, (st_data_t)&trackbar->name, (st_data_t)instance);
@@ -326,10 +325,13 @@ rb_set_trackbar(int argc, VALUE *argv, VALUE self)
  *   OpenCV::GUI::wait_key
  */
 VALUE
-rb_set_mouse_callback(VALUE self)
-{  
-  VALUE block = rb_block_given_p() ? rb_block_proc() : 0;
-  if (!block) {rb_raise(rb_eArgError, "block not given.");}
+rb_set_mouse_callback(int argc, VALUE* argv, VALUE self)
+{
+  if (!rb_block_given_p())
+    rb_raise(rb_eArgError, "block not given.");
+
+  VALUE block = Qnil;
+  rb_scan_args(argc, argv, "0&", &block);
   void *callback = (void *)alloc_callback(&mouse_callback, block);  
   cvSetMouseCallback(GET_WINDOW_NAME(self), (CvMouseCallback)callback);
   st_table *holder;
@@ -353,11 +355,11 @@ void
 mouse_callback(VALUE block, va_alist ap)
 {
   va_start_void(ap);
-  //VALUE ary = rb_ary_new2(4);
-  //for (int i = 0; i < 4; i++)
-  //  rb_ary_store(ary, i, INT2FIX(va_arg_int(ap)));
-  //rb_apply(block, rb_intern("call"), ary);
-  rb_funcall(block, rb_intern("call"), 1, cMouseEvent::new_object(va_arg_int(ap),va_arg_int(ap),va_arg_int(ap),va_arg_int(ap)));
+  int event = va_arg_int(ap);
+  int x = va_arg_int(ap);
+  int y = va_arg_int(ap);
+  int flags = va_arg_int(ap);
+  rb_funcall(block, rb_intern("call"), 1, cMouseEvent::new_object(event, x, y, flags));
   va_return_void(ap);
 }
 
diff --git a/ext/opencv/window.h b/ext/opencv/window.h
index 6b72cbe..0883851 100644
--- a/ext/opencv/window.h
+++ b/ext/opencv/window.h
@@ -40,9 +40,9 @@ VALUE rb_destroy(VALUE self);
 VALUE rb_destroy_all(VALUE klass);
 VALUE rb_resize(int argc, VALUE *argv, VALUE self);
 VALUE rb_move(int argc, VALUE *argv, VALUE self);
-VALUE rb_show_image(VALUE self, VALUE image);
+VALUE rb_show_image(int argc, VALUE *argv, VALUE self);
 VALUE rb_set_trackbar(int argc, VALUE *argv, VALUE self);
-VALUE rb_set_mouse_callback(VALUE self);
+VALUE rb_set_mouse_callback(int argc, VALUE* argv, VALUE self);
 
 void trackbar_callback(VALUE block, va_alist ap);
 void mouse_callback(VALUE block, va_alist ap);
diff --git a/extconf.rb b/extconf.rb
index 9475459..4e22228 100755
--- a/extconf.rb
+++ b/extconf.rb
@@ -72,7 +72,7 @@ else
 end
 
 # Quick fix for 1.8.7
-$CFLAGS << "-I#{File.dirname(__FILE__)}/ext/opencv"
+$CFLAGS << " -I#{File.dirname(__FILE__)}/ext/opencv"
 
 # step-final. create Makefile
 create_makefile("opencv", "./ext/opencv")
diff --git a/test/test_opencv.rb b/test/test_opencv.rb
index e936aa8..dedc80b 100755
--- a/test/test_opencv.rb
+++ b/test/test_opencv.rb
@@ -99,6 +99,9 @@ class TestOpenCV < OpenCVTestCase
     assert_equal(2, CV_FM_8POINT)
     assert_equal(8, CV_FM_RANSAC)
     assert_equal(4, CV_FM_LMEDS)
+
+    # Flags of window
+    assert_equal(1, CV_WINDOW_AUTOSIZE)
   end
 
   def test_symbols
diff --git a/test/test_window.rb b/test/test_window.rb
new file mode 100755
index 0000000..38948b9
--- /dev/null
+++ b/test/test_window.rb
@@ -0,0 +1,115 @@
+#!/usr/bin/env ruby
+# -*- mode: ruby; coding: utf-8-unix -*- 
+require 'test/unit'
+require 'opencv'
+require File.expand_path(File.dirname(__FILE__)) + '/helper'
+
+include OpenCV
+include GUI
+
+# Tests for OpenCV::Window
+class TestWindow < OpenCVTestCase
+  def setup
+    @window1 = Window.new('window1')
+    @window2 = Window.new('window2', CV_WINDOW_AUTOSIZE)
+    @window3 = Window.new('window3', 0)
+  end
+
+  def teardown
+    Window::destroy_all
+  end
+  
+  def test_initialize
+    [Window.new('w1'), Window.new('w2', CV_WINDOW_AUTOSIZE), Window.new('w3', 0)].each { |w|
+      assert_not_nil(w)
+      assert_equal(Window, w.class)
+    }
+
+    assert_raise(TypeError) {
+      Window.new('w4', 'foobar')
+    }
+
+    assert_raise(StandardError) {
+      Window.new('w5')
+      Window.new('w5')
+    }
+  end
+
+  def test_alive
+    assert(@window1.alive?)
+    @window1.destroy
+    assert(!(@window1.alive?))
+  end
+
+  def test_destroy
+    @window1.destroy
+    assert(!(@window1.alive?))
+  end
+
+  def test_destroy_all
+    Window::destroy_all
+    assert(!(@window1.alive?))
+    assert(!(@window2.alive?))
+    assert(!(@window3.alive?))
+  end
+
+  def test_resize
+    @window1.resize(CvSize.new(10, 20))
+    @window2.resize(100, 200)
+    assert_raise(ArgumentError) {
+      @window3.resize
+    }
+
+    # Uncomment the following lines to show the results
+    # @window1.show(CvMat.new(10, 20))
+    # @window2.show(CvMat.new(100, 200))
+    # GUI::wait_key
+  end
+
+  def test_move
+    @window1.move(CvPoint.new(10, 20))
+    @window2.move(100, 200)
+    assert_raise(ArgumentError) {
+      @window3.move
+    }
+
+    # Uncomment the following lines to show the results
+    # @window1.show(CvMat.new(10, 20))
+    # @window2.show(CvMat.new(100, 200))
+    # GUI::wait_key
+  end
+
+  def test_show_image
+    img = IplImage.load(FILENAME_CAT, CV_LOAD_IMAGE_ANYDEPTH | CV_LOAD_IMAGE_ANYCOLOR)
+    @window1.show_image(img)
+    @window2.show # Alias
+
+    # Uncomment the following lines to show the results
+    # GUI::wait_key
+  end
+
+  def test_set_trackbar
+    tr1 = @window1.set_trackbar('trackbar1', 100) { |value|
+      puts value
+    }
+    assert_equal(Trackbar, tr1.class)
+
+    trackbar2 = Trackbar.new('trackbar2', 10, 1) {}
+    tr2 = @window2.set_trackbar(trackbar2)
+    assert_equal(Trackbar, tr2.class)
+  end
+
+  def test_set_mouseevent
+    @window1.set_mouse_callback { |mouse|
+      e = "#{mouse.x}, #{mouse.y} : #{mouse.event} : "
+      e << "<L>" if mouse.left_button?
+      e << "<R>" if mouse.right_button?
+      e << "<M>" if mouse.middle_button?
+      e << "[CTRL]" if mouse.ctrl_key?
+      e << "[SHIFT]" if mouse.shift_key?
+      e << "[ALT]" if mouse.alt_key?
+      puts e
+    }
+  end
+end
+