def test_without_subsampling(self):
original = np.arange(6).reshape(2, 3)
config = Configuration(width=3, height=2, block_size=1)
restored = decompress_band(compress_band(original, config), config)
self.assertTrue(np.allclose(original, restored, rtol=0.000001))
def test_compress_and_decompress_on_array(self):
original = np.arange(128).reshape(8, 16)
config = Configuration(width=16, height=8, block_size=3)
restored = decompress_band(compress_band(original, config), config)
self.assertTrue(np.allclose(original, restored, rtol=1))
def test_fourier_transform_option(self):
original = np.arange(128).reshape(8, 16)
config = Configuration(width=16,
height=8,
block_size=3,
transform='DFT')
restored = decompress_band(compress_band(original, config), config)
self.assertTrue(np.allclose(original, restored, rtol=1))
def test_preserves_allowed_range(self):
original = np.array([[220, 255, 123, 205], [255, 255, 112, 10],
[15, 51, 83, 221], [239, 73, 62, 22]])
self.assertTrue(np.all(original < 256))
self.assertTrue(np.all(original > -1))
config = Configuration(width=4,
height=4,
block_size=1,
dct_size=2,
quantization=QuantizationMethod('divide',
divisor=129))
restored = decompress_band(compress_band(original, config), config)
self.assertTrue(np.all(restored < 256))
self.assertTrue(np.all(restored > -1))
def test_with_1pixel_blocks(self):
original = np.arange(64).reshape(8, 8)
config = Configuration(width=8, height=8, block_size=1, dct_size=1)
restored = decompress_band(compress_band(original, config), config)
self.assertTrue(np.allclose(original, restored, rtol=0.000001))