Coverage for tests / test_image.py: 18%

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1# This file is part of lsst-images. 

2# 

3# Developed for the LSST Data Management System. 

4# This product includes software developed by the LSST Project 

5# (https://www.lsst.org). 

6# See the COPYRIGHT file at the top-level directory of this distribution 

7# for details of code ownership. 

8# 

9# Use of this source code is governed by a 3-clause BSD-style 

10# license that can be found in the LICENSE file. 

11 

12from __future__ import annotations 

13 

14import os 

15import unittest 

16 

17import astropy.io.fits 

18import astropy.units as u 

19import numpy as np 

20from astro_metadata_translator import ObservationInfo 

21 

22import lsst.utils.tests 

23from lsst.images import Box, DetectorFrame, Image 

24from lsst.images.tests import ( 

25 assert_close, 

26 assert_images_equal, 

27 assert_projections_equal, 

28 compare_image_to_legacy, 

29 make_random_projection, 

30) 

31 

32DATA_DIR = os.environ.get("TESTDATA_IMAGES_DIR", None) 

33 

34 

35class ImageTestCase(unittest.TestCase): 

36 """Tests for the Image class.""" 

37 

38 def test_basics(self): 

39 """Test basic constructor patterns.""" 

40 image = Image(42, shape=(5, 5), metadata={"three": 3}) 

41 assert_close(self, image.array, np.zeros([5, 5], dtype=np.int64) + 42) 

42 self.assertEqual(image.metadata["three"], 3) 

43 

44 data = np.array([[1, 2, 3, 4], [5, 6, 7, 8], [9, 10, 11, 12]]) 

45 image = Image(data) 

46 subset = image[Box.factory[:3, 1:3]] 

47 subset2 = image.absolute[:3, 1:3] 

48 assert_images_equal(self, subset2, subset, expect_view=True) 

49 

50 assert_images_equal(self, image.copy(), image, expect_view=False) 

51 

52 # Add an explicit bounding box and then slice it. 

53 image = Image(data, bbox=Box.factory[-2:1, 10:14]) 

54 with self.assertRaises(IndexError): 

55 # Same slice no longer works in absolute slicing because we have 

56 # moved origin. 

57 image.absolute[:3, 1:3] 

58 # That slice does still work in local coordinates. 

59 assert_close(self, image.local[:3, 1:3].array, subset2.array) 

60 # And we can write an equivalent slice in absolute coordinates. 

61 assert_close(self, image.absolute[:0, 11:13].array, np.array([[2, 3], [6, 7]])) 

62 

63 # Test __eq__ behavior. 

64 self.assertEqual(image[...], image) 

65 self.assertEqual(image.__eq__(data), NotImplemented) 

66 self.assertNotEqual(image, list(data)) 

67 

68 with self.assertRaises(ValueError): 

69 # bbox does not match array shape. 

70 Image(np.array([[1, 2, 3], [4, 5, 6]]), bbox=Box.factory[0:2, 0:4]) 

71 

72 with self.assertRaises(ValueError): 

73 # shape does not match array shape. 

74 Image(np.array([[2, 3, 4], [6, 7, 8]]), shape=[5, 2]) 

75 

76 with self.assertRaises(TypeError): 

77 # shape and bbox both None. 

78 Image() 

79 

80 with self.assertRaises(ValueError): 

81 # Shape mismatch. 

82 Image(shape=[3, 6], bbox=Box.factory[-5:10, 0:10]) 

83 

84 def test_quantity(self): 

85 """Test quantities.""" 

86 data = np.array([[1.0, 2.0, 3.0, 4.0], [5.0, 6.0, 7.0, 8.0], [9.0, 10.0, 11.0, 12.0]]) 

87 data2 = data.copy() * 2.0 

88 image = Image(data, unit=u.mJy, bbox=Box.factory[-2:1, 3:7]) 

89 

90 q = image.quantity 

91 self.assertEqual(q[1, 0], 5.0 * u.mJy) 

92 image.quantity = image.array * 10.0 * u.uJy 

93 q = image.quantity 

94 self.assertEqual(q[1, 0], 0.05 * u.mJy) 

95 

96 image2 = Image(data2, unit=u.Jy) 

97 image[Box.factory[-1:0, 5:7]] = image2.local[1:2, 2:4] 

98 assert_close( 

99 self, 

100 image.array, 

101 np.array([[0.01, 0.02, 0.03, 0.04], [0.05, 0.06, 14000.0, 16000.0], [0.09, 0.1, 0.11, 0.12]]), 

102 ) 

103 

104 def test_read_write(self): 

105 """Round trip through file.""" 

106 data = np.array([[1.0, 2.0, np.nan, 4.0], [5.0, 6.0, 7.0, 8.0], [9.0, 10.0, 11.0, 12.0]]) 

107 md = {"int": 1, "float": 42.0, "bool": False, "long string header": "This is a string"} 

108 obsinfo = ObservationInfo(telescope="Simonyi", instrument="LSSTCam", relative_humidity=23.5) 

109 det_frame = DetectorFrame(instrument="Inst", visit=1234, detector=1, bbox=Box.factory[1:4096, 1:4096]) 

110 rng = np.random.default_rng(500) 

111 projection = make_random_projection(rng, det_frame, Box.factory[1:4096, 1:4096]) 

112 

113 image = Image( 

114 data, 

115 unit=u.nJy, 

116 metadata=md, 

117 obs_info=obsinfo, 

118 bbox=Box.factory[-2:1, 3:7], 

119 projection=projection, 

120 ) 

121 

122 with lsst.utils.tests.getTempFilePath(".fits") as tmpFile: 

123 image.write_fits(tmpFile) 

124 

125 new = Image.read_fits(tmpFile) 

126 self.assertEqual(new, image) 

127 

128 # __eq__ does not test all components. 

129 self.assertEqual(new.obs_info, image.obs_info) 

130 self.assertEqual(new.metadata, image.metadata) 

131 self.maxDiff = None 

132 assert_projections_equal(self, new.projection, image.projection, expect_identity=False) 

133 

134 # Read subset. 

135 subset = Image.read_fits(tmpFile, bbox=Box.factory[-2:0, 5:7]) 

136 self.assertEqual(subset, image.absolute[-2:0, 5:7]) 

137 self.assertEqual(subset, image.local[0:2, 2:4]) 

138 self.assertEqual(str(subset), "Image([y=-2:0, x=5:7], float64)") 

139 self.assertEqual( 

140 repr(subset), 

141 "Image(..., bbox=Box(y=Interval(start=-2, stop=0), x=Interval(start=5, stop=7)), " 

142 "dtype=dtype('float64'))", 

143 ) 

144 

145 # Check that WCS headers were written out. 

146 with astropy.io.fits.open(tmpFile) as hdul: 

147 hdu1 = hdul[1] 

148 hdr1 = hdu1.header 

149 self.assertEqual(hdr1["CTYPE1"], "RA---TAN") 

150 

151 @unittest.skipUnless(DATA_DIR is not None, "TESTDATA_IMAGES_DIR is not in the environment.") 

152 def test_legacy(self) -> None: 

153 """Test Image.read_legacy, Image.to_legacy, and Image.from_legacy.""" 

154 assert DATA_DIR is not None, "Guaranteed by decorator." 

155 filename = os.path.join(DATA_DIR, "dp2", "legacy", "visit_image.fits") 

156 det_frame = DetectorFrame(instrument="Inst", visit=1234, detector=1, bbox=Box.factory[1:4096, 1:4096]) 

157 image = Image.read_legacy(filename, preserve_quantization=True, fits_wcs_frame=det_frame) 

158 try: 

159 from lsst.afw.image import MaskedImageFitsReader 

160 except ImportError: 

161 raise unittest.SkipTest("'lsst.afw.image' could not be imported.") from None 

162 reader = MaskedImageFitsReader(filename) 

163 legacy_image = reader.readImage() 

164 compare_image_to_legacy(self, image, legacy_image, expect_view=False) 

165 # Converting back to afw will not share memory, because 

166 # preserve_quantization=True makes the array read-only and to_legacy 

167 # has to copy in that case. 

168 compare_image_to_legacy(self, image, image.to_legacy(), expect_view=False) 

169 # Converting from afw will always share memory. 

170 image_view = Image.from_legacy(legacy_image) 

171 compare_image_to_legacy(self, image_view, legacy_image, expect_view=True) 

172 # Converting back to afw from the in-memory view will be another view. 

173 compare_image_to_legacy(self, image_view, image_view.to_legacy(), expect_view=True) 

174 

175 

176if __name__ == "__main__": 

177 unittest.main()