Pillow/Tests/test_file_png.py
Jon Dufresne 4f185329f4 Streamline test skipping based on supported features
This adds a new test decorator: skip_unless_feature(). The argument is
the same as passed to features.check(). If the feature is not supported,
the test will be skipped.

This removes several kinds of boilerplate copied and pasted around tests
so test feature checking is handled and displayed more consistently.

Refs #4193
2020-02-18 13:07:01 -08:00

656 lines
22 KiB
Python

import unittest
import zlib
from io import BytesIO
import pytest
from PIL import Image, ImageFile, PngImagePlugin
from .helper import (
PillowLeakTestCase,
PillowTestCase,
assert_image,
assert_image_equal,
assert_image_similar,
hopper,
is_big_endian,
is_win32,
on_ci,
skip_unless_feature,
)
# sample png stream
TEST_PNG_FILE = "Tests/images/hopper.png"
# stuff to create inline PNG images
MAGIC = PngImagePlugin._MAGIC
def chunk(cid, *data):
test_file = BytesIO()
PngImagePlugin.putchunk(*(test_file, cid) + data)
return test_file.getvalue()
o32 = PngImagePlugin.o32
IHDR = chunk(b"IHDR", o32(1), o32(1), b"\x08\x02", b"\0\0\0")
IDAT = chunk(b"IDAT")
IEND = chunk(b"IEND")
HEAD = MAGIC + IHDR
TAIL = IDAT + IEND
def load(data):
return Image.open(BytesIO(data))
def roundtrip(im, **options):
out = BytesIO()
im.save(out, "PNG", **options)
out.seek(0)
return Image.open(out)
@skip_unless_feature("zlib")
class TestFilePng(PillowTestCase):
def get_chunks(self, filename):
chunks = []
with open(filename, "rb") as fp:
fp.read(8)
with PngImagePlugin.PngStream(fp) as png:
while True:
cid, pos, length = png.read()
chunks.append(cid)
try:
s = png.call(cid, pos, length)
except EOFError:
break
png.crc(cid, s)
return chunks
@pytest.mark.xfail(is_big_endian() and on_ci(), reason="Fails on big-endian")
def test_sanity(self):
# internal version number
self.assertRegex(Image.core.zlib_version, r"\d+\.\d+\.\d+(\.\d+)?$")
test_file = self.tempfile("temp.png")
hopper("RGB").save(test_file)
with Image.open(test_file) as im:
im.load()
self.assertEqual(im.mode, "RGB")
self.assertEqual(im.size, (128, 128))
self.assertEqual(im.format, "PNG")
self.assertEqual(im.get_format_mimetype(), "image/png")
for mode in ["1", "L", "P", "RGB", "I", "I;16"]:
im = hopper(mode)
im.save(test_file)
with Image.open(test_file) as reloaded:
if mode == "I;16":
reloaded = reloaded.convert(mode)
assert_image_equal(reloaded, im)
def test_invalid_file(self):
invalid_file = "Tests/images/flower.jpg"
self.assertRaises(SyntaxError, PngImagePlugin.PngImageFile, invalid_file)
def test_broken(self):
# Check reading of totally broken files. In this case, the test
# file was checked into Subversion as a text file.
test_file = "Tests/images/broken.png"
self.assertRaises(IOError, Image.open, test_file)
def test_bad_text(self):
# Make sure PIL can read malformed tEXt chunks (@PIL152)
im = load(HEAD + chunk(b"tEXt") + TAIL)
self.assertEqual(im.info, {})
im = load(HEAD + chunk(b"tEXt", b"spam") + TAIL)
self.assertEqual(im.info, {"spam": ""})
im = load(HEAD + chunk(b"tEXt", b"spam\0") + TAIL)
self.assertEqual(im.info, {"spam": ""})
im = load(HEAD + chunk(b"tEXt", b"spam\0egg") + TAIL)
self.assertEqual(im.info, {"spam": "egg"})
im = load(HEAD + chunk(b"tEXt", b"spam\0egg\0") + TAIL)
self.assertEqual(im.info, {"spam": "egg\x00"})
def test_bad_ztxt(self):
# Test reading malformed zTXt chunks (python-pillow/Pillow#318)
im = load(HEAD + chunk(b"zTXt") + TAIL)
self.assertEqual(im.info, {})
im = load(HEAD + chunk(b"zTXt", b"spam") + TAIL)
self.assertEqual(im.info, {"spam": ""})
im = load(HEAD + chunk(b"zTXt", b"spam\0") + TAIL)
self.assertEqual(im.info, {"spam": ""})
im = load(HEAD + chunk(b"zTXt", b"spam\0\0") + TAIL)
self.assertEqual(im.info, {"spam": ""})
im = load(HEAD + chunk(b"zTXt", b"spam\0\0" + zlib.compress(b"egg")[:1]) + TAIL)
self.assertEqual(im.info, {"spam": ""})
im = load(HEAD + chunk(b"zTXt", b"spam\0\0" + zlib.compress(b"egg")) + TAIL)
self.assertEqual(im.info, {"spam": "egg"})
def test_bad_itxt(self):
im = load(HEAD + chunk(b"iTXt") + TAIL)
self.assertEqual(im.info, {})
im = load(HEAD + chunk(b"iTXt", b"spam") + TAIL)
self.assertEqual(im.info, {})
im = load(HEAD + chunk(b"iTXt", b"spam\0") + TAIL)
self.assertEqual(im.info, {})
im = load(HEAD + chunk(b"iTXt", b"spam\0\x02") + TAIL)
self.assertEqual(im.info, {})
im = load(HEAD + chunk(b"iTXt", b"spam\0\0\0foo\0") + TAIL)
self.assertEqual(im.info, {})
im = load(HEAD + chunk(b"iTXt", b"spam\0\0\0en\0Spam\0egg") + TAIL)
self.assertEqual(im.info, {"spam": "egg"})
self.assertEqual(im.info["spam"].lang, "en")
self.assertEqual(im.info["spam"].tkey, "Spam")
im = load(
HEAD
+ chunk(b"iTXt", b"spam\0\1\0en\0Spam\0" + zlib.compress(b"egg")[:1])
+ TAIL
)
self.assertEqual(im.info, {"spam": ""})
im = load(
HEAD
+ chunk(b"iTXt", b"spam\0\1\1en\0Spam\0" + zlib.compress(b"egg"))
+ TAIL
)
self.assertEqual(im.info, {})
im = load(
HEAD
+ chunk(b"iTXt", b"spam\0\1\0en\0Spam\0" + zlib.compress(b"egg"))
+ TAIL
)
self.assertEqual(im.info, {"spam": "egg"})
self.assertEqual(im.info["spam"].lang, "en")
self.assertEqual(im.info["spam"].tkey, "Spam")
def test_interlace(self):
test_file = "Tests/images/pil123p.png"
with Image.open(test_file) as im:
assert_image(im, "P", (162, 150))
self.assertTrue(im.info.get("interlace"))
im.load()
test_file = "Tests/images/pil123rgba.png"
with Image.open(test_file) as im:
assert_image(im, "RGBA", (162, 150))
self.assertTrue(im.info.get("interlace"))
im.load()
def test_load_transparent_p(self):
test_file = "Tests/images/pil123p.png"
with Image.open(test_file) as im:
assert_image(im, "P", (162, 150))
im = im.convert("RGBA")
assert_image(im, "RGBA", (162, 150))
# image has 124 unique alpha values
self.assertEqual(len(im.getchannel("A").getcolors()), 124)
def test_load_transparent_rgb(self):
test_file = "Tests/images/rgb_trns.png"
with Image.open(test_file) as im:
self.assertEqual(im.info["transparency"], (0, 255, 52))
assert_image(im, "RGB", (64, 64))
im = im.convert("RGBA")
assert_image(im, "RGBA", (64, 64))
# image has 876 transparent pixels
self.assertEqual(im.getchannel("A").getcolors()[0][0], 876)
def test_save_p_transparent_palette(self):
in_file = "Tests/images/pil123p.png"
with Image.open(in_file) as im:
# 'transparency' contains a byte string with the opacity for
# each palette entry
self.assertEqual(len(im.info["transparency"]), 256)
test_file = self.tempfile("temp.png")
im.save(test_file)
# check if saved image contains same transparency
with Image.open(test_file) as im:
self.assertEqual(len(im.info["transparency"]), 256)
assert_image(im, "P", (162, 150))
im = im.convert("RGBA")
assert_image(im, "RGBA", (162, 150))
# image has 124 unique alpha values
self.assertEqual(len(im.getchannel("A").getcolors()), 124)
def test_save_p_single_transparency(self):
in_file = "Tests/images/p_trns_single.png"
with Image.open(in_file) as im:
# pixel value 164 is full transparent
self.assertEqual(im.info["transparency"], 164)
self.assertEqual(im.getpixel((31, 31)), 164)
test_file = self.tempfile("temp.png")
im.save(test_file)
# check if saved image contains same transparency
with Image.open(test_file) as im:
self.assertEqual(im.info["transparency"], 164)
self.assertEqual(im.getpixel((31, 31)), 164)
assert_image(im, "P", (64, 64))
im = im.convert("RGBA")
assert_image(im, "RGBA", (64, 64))
self.assertEqual(im.getpixel((31, 31)), (0, 255, 52, 0))
# image has 876 transparent pixels
self.assertEqual(im.getchannel("A").getcolors()[0][0], 876)
def test_save_p_transparent_black(self):
# check if solid black image with full transparency
# is supported (check for #1838)
im = Image.new("RGBA", (10, 10), (0, 0, 0, 0))
self.assertEqual(im.getcolors(), [(100, (0, 0, 0, 0))])
im = im.convert("P")
test_file = self.tempfile("temp.png")
im.save(test_file)
# check if saved image contains same transparency
with Image.open(test_file) as im:
self.assertEqual(len(im.info["transparency"]), 256)
assert_image(im, "P", (10, 10))
im = im.convert("RGBA")
assert_image(im, "RGBA", (10, 10))
self.assertEqual(im.getcolors(), [(100, (0, 0, 0, 0))])
def test_save_greyscale_transparency(self):
for mode, num_transparent in {"1": 1994, "L": 559, "I": 559}.items():
in_file = "Tests/images/" + mode.lower() + "_trns.png"
with Image.open(in_file) as im:
self.assertEqual(im.mode, mode)
self.assertEqual(im.info["transparency"], 255)
im_rgba = im.convert("RGBA")
self.assertEqual(im_rgba.getchannel("A").getcolors()[0][0], num_transparent)
test_file = self.tempfile("temp.png")
im.save(test_file)
with Image.open(test_file) as test_im:
self.assertEqual(test_im.mode, mode)
self.assertEqual(test_im.info["transparency"], 255)
assert_image_equal(im, test_im)
test_im_rgba = test_im.convert("RGBA")
self.assertEqual(
test_im_rgba.getchannel("A").getcolors()[0][0], num_transparent
)
def test_save_rgb_single_transparency(self):
in_file = "Tests/images/caption_6_33_22.png"
with Image.open(in_file) as im:
test_file = self.tempfile("temp.png")
im.save(test_file)
def test_load_verify(self):
# Check open/load/verify exception (@PIL150)
with Image.open(TEST_PNG_FILE) as im:
# Assert that there is no unclosed file warning
pytest.warns(None, im.verify)
with Image.open(TEST_PNG_FILE) as im:
im.load()
self.assertRaises(RuntimeError, im.verify)
def test_verify_struct_error(self):
# Check open/load/verify exception (#1755)
# offsets to test, -10: breaks in i32() in read. (IOError)
# -13: breaks in crc, txt chunk.
# -14: malformed chunk
for offset in (-10, -13, -14):
with open(TEST_PNG_FILE, "rb") as f:
test_file = f.read()[:offset]
with Image.open(BytesIO(test_file)) as im:
self.assertIsNotNone(im.fp)
self.assertRaises((IOError, SyntaxError), im.verify)
def test_verify_ignores_crc_error(self):
# check ignores crc errors in ancillary chunks
chunk_data = chunk(b"tEXt", b"spam")
broken_crc_chunk_data = chunk_data[:-1] + b"q" # break CRC
image_data = HEAD + broken_crc_chunk_data + TAIL
self.assertRaises(SyntaxError, PngImagePlugin.PngImageFile, BytesIO(image_data))
ImageFile.LOAD_TRUNCATED_IMAGES = True
try:
im = load(image_data)
self.assertIsNotNone(im)
finally:
ImageFile.LOAD_TRUNCATED_IMAGES = False
def test_verify_not_ignores_crc_error_in_required_chunk(self):
# check does not ignore crc errors in required chunks
image_data = MAGIC + IHDR[:-1] + b"q" + TAIL
ImageFile.LOAD_TRUNCATED_IMAGES = True
try:
self.assertRaises(
SyntaxError, PngImagePlugin.PngImageFile, BytesIO(image_data)
)
finally:
ImageFile.LOAD_TRUNCATED_IMAGES = False
def test_roundtrip_dpi(self):
# Check dpi roundtripping
with Image.open(TEST_PNG_FILE) as im:
im = roundtrip(im, dpi=(100, 100))
self.assertEqual(im.info["dpi"], (100, 100))
def test_load_dpi_rounding(self):
# Round up
with Image.open(TEST_PNG_FILE) as im:
self.assertEqual(im.info["dpi"], (96, 96))
# Round down
with Image.open("Tests/images/icc_profile_none.png") as im:
self.assertEqual(im.info["dpi"], (72, 72))
def test_save_dpi_rounding(self):
with Image.open(TEST_PNG_FILE) as im:
im = roundtrip(im, dpi=(72.2, 72.2))
self.assertEqual(im.info["dpi"], (72, 72))
im = roundtrip(im, dpi=(72.8, 72.8))
self.assertEqual(im.info["dpi"], (73, 73))
def test_roundtrip_text(self):
# Check text roundtripping
with Image.open(TEST_PNG_FILE) as im:
info = PngImagePlugin.PngInfo()
info.add_text("TXT", "VALUE")
info.add_text("ZIP", "VALUE", zip=True)
im = roundtrip(im, pnginfo=info)
self.assertEqual(im.info, {"TXT": "VALUE", "ZIP": "VALUE"})
self.assertEqual(im.text, {"TXT": "VALUE", "ZIP": "VALUE"})
def test_roundtrip_itxt(self):
# Check iTXt roundtripping
im = Image.new("RGB", (32, 32))
info = PngImagePlugin.PngInfo()
info.add_itxt("spam", "Eggs", "en", "Spam")
info.add_text("eggs", PngImagePlugin.iTXt("Spam", "en", "Eggs"), zip=True)
im = roundtrip(im, pnginfo=info)
self.assertEqual(im.info, {"spam": "Eggs", "eggs": "Spam"})
self.assertEqual(im.text, {"spam": "Eggs", "eggs": "Spam"})
self.assertEqual(im.text["spam"].lang, "en")
self.assertEqual(im.text["spam"].tkey, "Spam")
self.assertEqual(im.text["eggs"].lang, "en")
self.assertEqual(im.text["eggs"].tkey, "Eggs")
def test_nonunicode_text(self):
# Check so that non-Unicode text is saved as a tEXt rather than iTXt
im = Image.new("RGB", (32, 32))
info = PngImagePlugin.PngInfo()
info.add_text("Text", "Ascii")
im = roundtrip(im, pnginfo=info)
self.assertIsInstance(im.info["Text"], str)
def test_unicode_text(self):
# Check preservation of non-ASCII characters
def rt_text(value):
im = Image.new("RGB", (32, 32))
info = PngImagePlugin.PngInfo()
info.add_text("Text", value)
im = roundtrip(im, pnginfo=info)
self.assertEqual(im.info, {"Text": value})
rt_text(" Aa" + chr(0xA0) + chr(0xC4) + chr(0xFF)) # Latin1
rt_text(chr(0x400) + chr(0x472) + chr(0x4FF)) # Cyrillic
# CJK:
rt_text(chr(0x4E00) + chr(0x66F0) + chr(0x9FBA) + chr(0x3042) + chr(0xAC00))
rt_text("A" + chr(0xC4) + chr(0x472) + chr(0x3042)) # Combined
def test_scary(self):
# Check reading of evil PNG file. For information, see:
# http://scary.beasts.org/security/CESA-2004-001.txt
# The first byte is removed from pngtest_bad.png
# to avoid classification as malware.
with open("Tests/images/pngtest_bad.png.bin", "rb") as fd:
data = b"\x89" + fd.read()
pngfile = BytesIO(data)
self.assertRaises(IOError, Image.open, pngfile)
def test_trns_rgb(self):
# Check writing and reading of tRNS chunks for RGB images.
# Independent file sample provided by Sebastian Spaeth.
test_file = "Tests/images/caption_6_33_22.png"
with Image.open(test_file) as im:
self.assertEqual(im.info["transparency"], (248, 248, 248))
# check saving transparency by default
im = roundtrip(im)
self.assertEqual(im.info["transparency"], (248, 248, 248))
im = roundtrip(im, transparency=(0, 1, 2))
self.assertEqual(im.info["transparency"], (0, 1, 2))
def test_trns_p(self):
# Check writing a transparency of 0, issue #528
im = hopper("P")
im.info["transparency"] = 0
f = self.tempfile("temp.png")
im.save(f)
with Image.open(f) as im2:
self.assertIn("transparency", im2.info)
assert_image_equal(im2.convert("RGBA"), im.convert("RGBA"))
def test_trns_null(self):
# Check reading images with null tRNS value, issue #1239
test_file = "Tests/images/tRNS_null_1x1.png"
with Image.open(test_file) as im:
self.assertEqual(im.info["transparency"], 0)
def test_save_icc_profile(self):
with Image.open("Tests/images/icc_profile_none.png") as im:
self.assertIsNone(im.info["icc_profile"])
with Image.open("Tests/images/icc_profile.png") as with_icc:
expected_icc = with_icc.info["icc_profile"]
im = roundtrip(im, icc_profile=expected_icc)
self.assertEqual(im.info["icc_profile"], expected_icc)
def test_discard_icc_profile(self):
with Image.open("Tests/images/icc_profile.png") as im:
im = roundtrip(im, icc_profile=None)
self.assertNotIn("icc_profile", im.info)
def test_roundtrip_icc_profile(self):
with Image.open("Tests/images/icc_profile.png") as im:
expected_icc = im.info["icc_profile"]
im = roundtrip(im)
self.assertEqual(im.info["icc_profile"], expected_icc)
def test_roundtrip_no_icc_profile(self):
with Image.open("Tests/images/icc_profile_none.png") as im:
self.assertIsNone(im.info["icc_profile"])
im = roundtrip(im)
self.assertNotIn("icc_profile", im.info)
def test_repr_png(self):
im = hopper()
with Image.open(BytesIO(im._repr_png_())) as repr_png:
self.assertEqual(repr_png.format, "PNG")
assert_image_equal(im, repr_png)
def test_chunk_order(self):
with Image.open("Tests/images/icc_profile.png") as im:
test_file = self.tempfile("temp.png")
im.convert("P").save(test_file, dpi=(100, 100))
chunks = self.get_chunks(test_file)
# https://www.w3.org/TR/PNG/#5ChunkOrdering
# IHDR - shall be first
self.assertEqual(chunks.index(b"IHDR"), 0)
# PLTE - before first IDAT
self.assertLess(chunks.index(b"PLTE"), chunks.index(b"IDAT"))
# iCCP - before PLTE and IDAT
self.assertLess(chunks.index(b"iCCP"), chunks.index(b"PLTE"))
self.assertLess(chunks.index(b"iCCP"), chunks.index(b"IDAT"))
# tRNS - after PLTE, before IDAT
self.assertGreater(chunks.index(b"tRNS"), chunks.index(b"PLTE"))
self.assertLess(chunks.index(b"tRNS"), chunks.index(b"IDAT"))
# pHYs - before IDAT
self.assertLess(chunks.index(b"pHYs"), chunks.index(b"IDAT"))
def test_getchunks(self):
im = hopper()
chunks = PngImagePlugin.getchunks(im)
self.assertEqual(len(chunks), 3)
def test_textual_chunks_after_idat(self):
with Image.open("Tests/images/hopper.png") as im:
self.assertIn("comment", im.text.keys())
for k, v in {
"date:create": "2014-09-04T09:37:08+03:00",
"date:modify": "2014-09-04T09:37:08+03:00",
}.items():
self.assertEqual(im.text[k], v)
# Raises a SyntaxError in load_end
with Image.open("Tests/images/broken_data_stream.png") as im:
with self.assertRaises(IOError):
self.assertIsInstance(im.text, dict)
# Raises a UnicodeDecodeError in load_end
with Image.open("Tests/images/truncated_image.png") as im:
# The file is truncated
self.assertRaises(IOError, lambda: im.text)
ImageFile.LOAD_TRUNCATED_IMAGES = True
self.assertIsInstance(im.text, dict)
ImageFile.LOAD_TRUNCATED_IMAGES = False
# Raises an EOFError in load_end
with Image.open("Tests/images/hopper_idat_after_image_end.png") as im:
self.assertEqual(im.text, {"TXT": "VALUE", "ZIP": "VALUE"})
def test_exif(self):
with Image.open("Tests/images/exif.png") as im:
exif = im._getexif()
self.assertEqual(exif[274], 1)
def test_exif_save(self):
with Image.open("Tests/images/exif.png") as im:
test_file = self.tempfile("temp.png")
im.save(test_file)
with Image.open(test_file) as reloaded:
exif = reloaded._getexif()
self.assertEqual(exif[274], 1)
def test_exif_from_jpg(self):
with Image.open("Tests/images/pil_sample_rgb.jpg") as im:
test_file = self.tempfile("temp.png")
im.save(test_file)
with Image.open(test_file) as reloaded:
exif = reloaded._getexif()
self.assertEqual(exif[305], "Adobe Photoshop CS Macintosh")
def test_exif_argument(self):
with Image.open(TEST_PNG_FILE) as im:
test_file = self.tempfile("temp.png")
im.save(test_file, exif=b"exifstring")
with Image.open(test_file) as reloaded:
self.assertEqual(reloaded.info["exif"], b"Exif\x00\x00exifstring")
@skip_unless_feature("webp")
@skip_unless_feature("webp_anim")
def test_apng(self):
with Image.open("Tests/images/iss634.apng") as im:
self.assertEqual(im.get_format_mimetype(), "image/apng")
# This also tests reading unknown PNG chunks (fcTL and fdAT) in load_end
with Image.open("Tests/images/iss634.webp") as expected:
assert_image_similar(im, expected, 0.23)
@unittest.skipIf(is_win32(), "requires Unix or macOS")
@skip_unless_feature("zlib")
class TestTruncatedPngPLeaks(PillowLeakTestCase):
mem_limit = 2 * 1024 # max increase in K
iterations = 100 # Leak is 56k/iteration, this will leak 5.6megs
def test_leak_load(self):
with open("Tests/images/hopper.png", "rb") as f:
DATA = BytesIO(f.read(16 * 1024))
ImageFile.LOAD_TRUNCATED_IMAGES = True
with Image.open(DATA) as im:
im.load()
def core():
with Image.open(DATA) as im:
im.load()
try:
self._test_leak(core)
finally:
ImageFile.LOAD_TRUNCATED_IMAGES = False