def test_sid(self):
# default sid is None
fi = FileImage(tif_path)
self.assertIsNone(fi.sid)
# SID can be set though
fi2 = FileImage(tif_path, sid=1500)
self.assertEqual(fi2.sid, 1500)
# SID also affects the dpi
orig_dpi = fi.dpi
scaled_dpi = fi2.dpi
self.assertEqual(orig_dpi, scaled_dpi*2/3)
def test_dpi_dpmm(self):
# DPI is usually in TIF files
fi = FileImage(tif_path)
# shouldn't raise
fi.dpi
fi.dpmm
# not in certain other files
fi_jpg = FileImage(png_path)
self.assertIsNone(fi_jpg.dpi)
# but DPI can be set though
fi_jpg2 = FileImage(png_path, dpi=100)
# shouldn't raise
fi_jpg2.dpi
fi_jpg2.dpmm
def test_dpi_dpmm(self):
# DPI is usually in TIF files
fi = FileImage(tif_path)
# shouldn't raise
fi.dpi
fi.dpmm
# not in certain other files
fi_jpg = FileImage(png_path)
with self.assertRaises(AttributeError):
fi_jpg.dpi
# but DPI can be set though
fi_jpg2 = FileImage(png_path, dpi=100)
# shouldn't raise
fi_jpg2.dpi
fi_jpg2.dpmm