Pillow/Tests/test_file_tiff_metadata.py
2015-04-24 09:26:52 +10:00

108 lines
3.5 KiB
Python

from helper import unittest, PillowTestCase, hopper
from PIL import Image, TiffImagePlugin, TiffTags
tag_ids = dict(zip(TiffTags.TAGS.values(), TiffTags.TAGS.keys()))
class TestFileTiffMetadata(PillowTestCase):
def test_rt_metadata(self):
""" Test writing arbitrary metadata into the tiff image directory
Use case is ImageJ private tags, one numeric, one arbitrary
data. https://github.com/python-pillow/Pillow/issues/291
"""
img = hopper()
textdata = "This is some arbitrary metadata for a text field"
floatdata = 12.345
doubledata = 67.89
info = TiffImagePlugin.ImageFileDirectory()
info[tag_ids['ImageJMetaDataByteCounts']] = len(textdata)
info[tag_ids['ImageJMetaData']] = textdata
info[tag_ids['RollAngle']] = floatdata
info.tagtype[tag_ids['RollAngle']] = 11
info[tag_ids['YawAngle']] = doubledata
info.tagtype[tag_ids['YawAngle']] = 12
f = self.tempfile("temp.tif")
img.save(f, tiffinfo=info)
loaded = Image.open(f)
self.assertEqual(loaded.tag[50838], (len(textdata),))
self.assertEqual(loaded.tag[50839], textdata)
self.assertAlmostEqual(loaded.tag[tag_ids['RollAngle']][0], floatdata,
places=5)
self.assertAlmostEqual(loaded.tag[tag_ids['YawAngle']][0], doubledata)
def test_read_metadata(self):
img = Image.open('Tests/images/hopper_g4.tif')
known = {'YResolution': ((4294967295, 113653537),),
'PlanarConfiguration': (1,),
'BitsPerSample': (1,),
'ImageLength': (128,),
'Compression': (4,),
'FillOrder': (1,),
'RowsPerStrip': (128,),
'ResolutionUnit': (3,),
'PhotometricInterpretation': (0,),
'PageNumber': (0, 1),
'XResolution': ((4294967295, 113653537),),
'ImageWidth': (128,),
'Orientation': (1,),
'StripByteCounts': (1968,),
'SamplesPerPixel': (1,),
'StripOffsets': (8,),
}
# self.assertEqual is equivalent,
# but less helpful in telling what's wrong.
named = img.tag.named()
for tag, value in named.items():
self.assertEqual(known[tag], value)
for tag, value in known.items():
self.assertEqual(value, named[tag])
def test_write_metadata(self):
""" Test metadata writing through the python code """
img = Image.open('Tests/images/hopper.tif')
f = self.tempfile('temp.tiff')
img.save(f, tiffinfo=img.tag)
loaded = Image.open(f)
original = img.tag.named()
reloaded = loaded.tag.named()
ignored = [
'StripByteCounts', 'RowsPerStrip', 'PageNumber', 'StripOffsets']
for tag, value in reloaded.items():
if tag not in ignored:
self.assertEqual(
original[tag], value, "%s didn't roundtrip" % tag)
for tag, value in original.items():
if tag not in ignored:
self.assertEqual(
value, reloaded[tag], "%s didn't roundtrip" % tag)
def test_no_duplicate_50741_tag(self):
self.assertEqual(tag_ids['MakerNoteSafety'], 50741)
self.assertEqual(tag_ids['BestQualityScale'], 50780)
if __name__ == '__main__':
unittest.main()
# End of file