From 2a256fda4ae69cf6beb91de502b49c8da7f583b6 Mon Sep 17 00:00:00 2001
From: ser1zw <azariahsawtikes@gmail.com>
Date: Thu, 13 Jan 2011 02:16:08 +0900
Subject: [PATCH] added tests for CvMat#dft and CvMat#dct

---
 test/test_cvmat_dxt.rb | 139 +++++++++++++++++++++++++++++++++++++++++
 1 file changed, 139 insertions(+)
 create mode 100755 test/test_cvmat_dxt.rb

diff --git a/test/test_cvmat_dxt.rb b/test/test_cvmat_dxt.rb
new file mode 100755
index 0000000..52413fd
--- /dev/null
+++ b/test/test_cvmat_dxt.rb
@@ -0,0 +1,139 @@
+#!/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
+
+# Tests for dft and dct functions of OpenCV::CvMat
+class TestCvMat_dxt < OpenCVTestCase
+  def test_dft_1D
+    n = 32
+    w = 2 * Math::PI / n
+    
+    mat0 = create_cvmat(n, 1, :cv32f, 2) { |j, i, c|
+      s = Math.sin(c * w)
+      CvScalar.new(s, s)
+    }
+
+    mat1 = mat0.dft(:forward)
+    mat2 = mat0.dft(:forward, :scale)
+    mat3 = mat0.dft(:forward, :scale).dft(:inverse)
+    n.times { |j|
+      if j == 1
+        assert_in_delta(n / 2, mat1[j, 0][0], 0.001)
+        assert_in_delta(-n / 2, mat1[j, 0][1], 0.001)
+        assert_in_delta(0.5, mat2[j, 0][0], 0.001)
+        assert_in_delta(-0.5, mat2[j, 0][1], 0.001)
+      elsif j == n - 1
+        assert_in_delta(-n / 2, mat1[j, 0][0], 0.001)
+        assert_in_delta(n / 2, mat1[j, 0][1], 0.001)
+        assert_in_delta(-0.5, mat2[j, 0][0], 0.001)
+        assert_in_delta(0.5, mat2[j, 0][1], 0.001)
+      else
+        assert_in_delta(0, mat1[j, 0][0], 0.001)
+        assert_in_delta(0, mat1[j, 0][1], 0.001)
+        assert_in_delta(0, mat2[j, 0][0], 0.001)
+        assert_in_delta(0, mat2[j, 0][1], 0.001)
+      end
+      assert_in_delta(mat0[j, 0][0], mat3[j, 0][0], 0.001)
+      assert_in_delta(mat0[j, 0][1], mat3[j, 0][1], 0.001)
+    }
+  end
+
+  def test_dft_2D
+    n = 32
+    w = 2 * Math::PI / n
+    c = 0
+    mat0 = CvMat.new(n, n, :cv32f, 2)
+    n.times { |j|
+      s = Math.sin(c * w)
+      n.times { |i|
+        mat0[j, i] = CvScalar.new(s, s)
+      }
+      c += 1
+    }
+
+    mat1 = mat0.dft(:forward)
+    mat2 = mat0.dft(:forward, :scale)
+    mat3 = mat0.dft(:forward, :scale).dft(:inverse)
+    n.times { |j|
+      n.times { |i|
+        if i == 0 and j == 1
+          assert_in_delta(n * n / 2, mat1[j, i][0], 0.001)
+          assert_in_delta(-n * n / 2, mat1[j, i][1], 0.001)
+          assert_in_delta(0.5, mat2[j, i][0], 0.001)
+          assert_in_delta(-0.5, mat2[j, i][1], 0.001)
+        elsif i == 0 and j == n - 1
+          assert_in_delta(-n * n / 2, mat1[j, i][0], 0.001)
+          assert_in_delta(n * n / 2, mat1[j, i][1], 0.001)
+          assert_in_delta(-0.5, mat2[j, i][0], 0.001)
+          assert_in_delta(0.5, mat2[j, i][1], 0.001)
+        else
+          assert_in_delta(0, mat1[j, i][0], 0.001)
+          assert_in_delta(0, mat1[j, i][1], 0.001)
+          assert_in_delta(0, mat2[j, i][0], 0.001)
+          assert_in_delta(0, mat2[j, i][1], 0.001)
+        end
+        assert_in_delta(mat0[j, 0][0], mat3[j, i][0], 0.001)
+        assert_in_delta(mat0[j, 0][1], mat3[j, i][1], 0.001)
+      }
+    }
+  end
+
+  def test_dct_1D
+    n = 8
+    w = 2 * Math::PI / n
+    
+    mat0 = create_cvmat(n, 1, :cv32f, 1) { |j, i, c|
+      s = Math.sin(c * w)
+      CvScalar.new(s)
+    }
+
+    mat1 = mat0.dct
+    mat2 = mat0.dct(:forward).dct(:inverse)
+    expected1 = [0, 1.599647, -0.765367, -0.906127, 0, -0.180240, 0, -0.042290]
+    n.times { |j|
+      assert_in_delta(expected1[j], mat1[j, 0][0], 0.001)
+      assert_in_delta(mat0[j, 0][0], mat2[j, 0][0], 0.001)
+    }
+  end
+
+  def test_dct_2D
+    n = 8
+    w = 2 * Math::PI / n
+    c = 0
+    mat0 = CvMat.new(n, n, :cv32f, 1)
+    n.times { |j|
+      s = Math.sin(c * w)
+      n.times { |i|
+        mat0[j, i] = CvScalar.new(s, s)
+      }
+      c += 1
+    }
+
+    mat1 = mat0.dct(:forward)
+    mat2 = mat0.dct(:forward).dct(:inverse)
+    n.times { |j|
+      n.times { |i|
+        if i == 0 and j == 1
+          assert_in_delta(4.524486, mat1[j, i][0], 0.001)
+        elsif i == 0 and j == 2
+          assert_in_delta(-2.164784, mat1[j, i][0], 0.001)
+        elsif i == 0 and j == 3
+          assert_in_delta(-2.562915, mat1[j, i][0], 0.001)
+        elsif i == 0 and j == 5
+          assert_in_delta(-0.509796, mat1[j, i][0], 0.001)
+        elsif i == 0 and j == 7
+          assert_in_delta(-0.119615, mat1[j, i][0], 0.001)
+        else
+          assert_in_delta(0, mat1[j, i][0], 0.001)
+        end
+        assert_in_delta(mat0[j, i][0], mat2[j, i][0], 0.001)
+      }
+    }
+  end
+end
+
+