mirror of
https://github.com/python-pillow/Pillow.git
synced 2024-12-25 01:16:16 +03:00
Merge pull request #818 from dolda2000/itxt
Added support for encoding and decoding iTXt chunks.
This commit is contained in:
Hugo
commit
328fd35dad
|
|
@ -147,6 +147,17 @@ class ChunkStream:
|
|||
|
||||
return cids
|
||||
|
||||
# --------------------------------------------------------------------
|
||||
# Subclass of string to allow iTXt chunks to look like strings while
|
||||
# keeping their extra information
|
||||
|
||||
class iTXt(str):
|
||||
@staticmethod
|
||||
def __new__(cls, text, lang, tkey):
|
||||
self = str.__new__(cls, text)
|
||||
self.lang = lang
|
||||
self.tkey = tkey
|
||||
return self
|
||||
|
||||
# --------------------------------------------------------------------
|
||||
# PNG chunk container (for use with save(pnginfo=))
|
||||
|
|
@ -159,14 +170,36 @@ class PngInfo:
|
|||
def add(self, cid, data):
|
||||
self.chunks.append((cid, data))
|
||||
|
||||
def add_itxt(self, key, value, lang="", tkey="", zip=False):
|
||||
if not isinstance(key, bytes):
|
||||
key = key.encode("latin-1", "strict")
|
||||
if not isinstance(value, bytes):
|
||||
value = value.encode("utf-8", "strict")
|
||||
if not isinstance(lang, bytes):
|
||||
lang = lang.encode("utf-8", "strict")
|
||||
if not isinstance(tkey, bytes):
|
||||
tkey = tkey.encode("utf-8", "strict")
|
||||
|
||||
if zip:
|
||||
import zlib
|
||||
self.add(b"iTXt", key + b"\0\x01\0" + lang + b"\0" + tkey + b"\0" + zlib.compress(value))
|
||||
else:
|
||||
self.add(b"iTXt", key + b"\0\0\0" + lang + b"\0" + tkey + b"\0" + value)
|
||||
|
||||
def add_text(self, key, value, zip=0):
|
||||
if isinstance(value, iTXt):
|
||||
return self.add_itxt(key, value, value.lang, value.tkey, bool(zip))
|
||||
|
||||
# The tEXt chunk stores latin-1 text
|
||||
if not isinstance(value, bytes):
|
||||
try:
|
||||
value = value.encode('latin-1', 'strict')
|
||||
except UnicodeError:
|
||||
return self.add_itxt(key, value, zip=bool(zip))
|
||||
|
||||
if not isinstance(key, bytes):
|
||||
key = key.encode('latin-1', 'strict')
|
||||
|
||||
if not isinstance(value, bytes):
|
||||
value = value.encode('latin-1', 'replace')
|
||||
|
||||
if zip:
|
||||
import zlib
|
||||
self.add(b"zTXt", key + b"\0\0" + zlib.compress(value))
|
||||
|
|
@ -329,6 +362,43 @@ class PngStream(ChunkStream):
|
|||
self.im_info[k] = self.im_text[k] = v
|
||||
return s
|
||||
|
||||
def chunk_iTXt(self, pos, length):
|
||||
|
||||
# international text
|
||||
r = s = ImageFile._safe_read(self.fp, length)
|
||||
try:
|
||||
k, r = r.split(b"\0", 1)
|
||||
except ValueError:
|
||||
return s
|
||||
if len(r) < 2:
|
||||
return s
|
||||
cf, cm, r = i8(r[0]), i8(r[1]), r[2:]
|
||||
try:
|
||||
lang, tk, v = r.split(b"\0", 2)
|
||||
except ValueError:
|
||||
return s
|
||||
if cf != 0:
|
||||
if cm == 0:
|
||||
import zlib
|
||||
try:
|
||||
v = zlib.decompress(v)
|
||||
except zlib.error:
|
||||
return s
|
||||
else:
|
||||
return s
|
||||
if bytes is not str:
|
||||
try:
|
||||
k = k.decode("latin-1", "strict")
|
||||
lang = lang.decode("utf-8", "strict")
|
||||
tk = tk.decode("utf-8", "strict")
|
||||
v = v.decode("utf-8", "strict")
|
||||
except UnicodeError:
|
||||
return s
|
||||
|
||||
self.im_info[k] = self.im_text[k] = iTXt(v, lang, tk)
|
||||
|
||||
return s
|
||||
|
||||
# --------------------------------------------------------------------
|
||||
# PNG reader
|
||||
|
||||
|
|
|
|||
|
|
@ -129,6 +129,39 @@ class TestFilePng(PillowTestCase):
|
|||
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, {})
|
||||
|
||||
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):
|
||||
|
||||
file = "Tests/images/pil123p.png"
|
||||
|
|
@ -232,6 +265,50 @@ class TestFilePng(PillowTestCase):
|
|||
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.assertEqual(type(im.info["Text"]), str)
|
||||
|
||||
def test_unicode_text(self):
|
||||
# Check preservation of non-ASCII characters on Python3
|
||||
# This cannot really be meaningfully tested on Python2,
|
||||
# since it didn't preserve charsets to begin with.
|
||||
|
||||
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})
|
||||
|
||||
if str is not bytes:
|
||||
rt_text(" Aa" + chr(0xa0) + chr(0xc4) + chr(0xff)) # Latin1
|
||||
rt_text(chr(0x400) + chr(0x472) + chr(0x4ff)) # Cyrillic
|
||||
rt_text(chr(0x4e00) + chr(0x66f0) + # CJK
|
||||
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
|
||||
|
|
|
|||
Loading…
Reference in New Issue
Block a user