Pillow/Tests/test_file_tiff_metadata.py
Antony Lee 974bcc074b Major rewrite of TIFF ImageFileDirectory.
Do not represent scalar tags as 1-element tuples.  Keep tag
type and count information in TiffTags.TAGS.  Normalize data in
ImageFileDirectory.__setitem__: wrap and unwrap tuples as needed,
convert rationals to floats.  (To ensure consistency, make the "tags"
attribute private.)  Interpret byte data as a series of integers rather
than a bytearray (which should only map to the "undefined" type).  On
Python3, if a str is assigned to an "undefined" tag, encode it as ASCII.

Note that a large number of tags have been removed from TiffTags.TAGS
because I do not have time to figure out the type and count of each of
them.  They should be restored before this gets merged in.

This obviously breaks backwards compatibility in a lot of ways...
2015-09-11 22:34:50 +01:00

103 lines
3.3 KiB
Python

from __future__ import division
from helper import unittest, PillowTestCase, hopper
from PIL import Image, TiffImagePlugin, TiffTags
tag_ids = {info.name: info.value for info in TiffTags.TAGS.values()}
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()
basetextdata = "This is some arbitrary metadata for a text field"
textdata = basetextdata + " \xff"
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(basetextdata + " ?"),))
self.assertEqual(loaded.tag[50839], basetextdata + " ?")
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(known, img.tag.named())
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