src/openpower/decoder/isa/fastdct-test.py

   1 #
   2 # Fast discrete cosine transform algorithms (Python)
   3 #
   4 # Copyright (c) 2020 Project Nayuki. (MIT License)
   5 # https://www.nayuki.io/page/fast-discrete-cosine-transform-algorithms
   6 #
   7 # Permission is hereby granted, free of charge, to any person obtaining a copy of
   8 # this software and associated documentation files (the "Software"), to deal in
   9 # the Software without restriction, including without limitation the rights to
  10 # use, copy, modify, merge, publish, distribute, sublicense, and/or sell
  11 # copies of the Software, and to permit persons to whom the Software is
  12 # furnished to do so, subject to the following conditions:
  13 # - The above copyright notice and this permission notice shall be included in
  14 #   all copies or substantial portions of the Software.
  15 # - The Software is provided "as is", without warranty of any kind, express or
  16 #   implied, including but not limited to the warranties of merchantability,
  17 #   fitness for a particular purpose and noninfringement. In no event shall the
  18 #   authors or copyright holders be liable for any claim, damages or other
  19 #   liability, whether in an action of contract, tort or otherwise,
  20 #   arising from, out of or in connection with the Software or the use
  21 #   or other dealings in the Software.
  22 #
  23
  24 import math, random, unittest
  25 import fastdctlee, naivedct
  26
  27
  28 class FastDctTest(unittest.TestCase):
  29
  30     def test_fast_dct_lee_vs_naive(self):
  31         for i in range(3, 10):
  32             n = 2**i
  33             vector = FastDctTest.nonrandom_vector(n)
  34             expect = naivedct.transform(vector)
  35             original = fastdctlee.transform(vector)
  36             actual = fastdctlee.transform2(vector)
  37             self.assertListAlmostEqual(actual, expect)
  38             expect = naivedct.inverse_transform(vector)
  39             actual = fastdctlee.inverse_transform(vector)
  40             self.assertListAlmostEqual(actual, expect)
  41
  42     def notest_fast_dct_lee_invertibility(self):
  43         for i in range(1, 10):
  44             n = 2**i
  45             vector = FastDctTest.random_vector(n)
  46             temp = fastdctlee.transform2(vector)
  47             temp = fastdctlee.inverse_transform(temp)
  48             temp = [(val * 2.0 / n) for val in temp]
  49             self.assertListAlmostEqual(vector, temp)
  50
  51     def assertListAlmostEqual(self, actual, expect):
  52         self.assertEqual(len(actual), len(expect))
  53         for (x, y) in zip(actual, expect):
  54             self.assertAlmostEqual(x, y, delta=FastDctTest._EPSILON)
  55
  56     @staticmethod
  57     def random_vector(n):
  58         return [random.uniform(-1.0, 1.0) for _ in range(n)]
  59
  60     @staticmethod
  61     def nonrandom_vector(n):
  62         return [(i-n/2.0) for i in range(n)]
  63
  64
  65     _EPSILON = 1e-9
  66
  67
  68 if __name__ == "__main__":
  69     unittest.main()