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diff --git a/lib/Python/Lib/PIL/PngImagePlugin.py b/lib/Python/Lib/PIL/PngImagePlugin.py
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+#
+# The Python Imaging Library.
+# $Id$
+#
+# PNG support code
+#
+# See "PNG (Portable Network Graphics) Specification, version 1.0;
+# W3C Recommendation", 1996-10-01, Thomas Boutell (ed.).
+#
+# history:
+# 1996-05-06 fl Created (couldn't resist it)
+# 1996-12-14 fl Upgraded, added read and verify support (0.2)
+# 1996-12-15 fl Separate PNG stream parser
+# 1996-12-29 fl Added write support, added getchunks
+# 1996-12-30 fl Eliminated circular references in decoder (0.3)
+# 1998-07-12 fl Read/write 16-bit images as mode I (0.4)
+# 2001-02-08 fl Added transparency support (from Zircon) (0.5)
+# 2001-04-16 fl Don't close data source in "open" method (0.6)
+# 2004-02-24 fl Don't even pretend to support interlaced files (0.7)
+# 2004-08-31 fl Do basic sanity check on chunk identifiers (0.8)
+# 2004-09-20 fl Added PngInfo chunk container
+# 2004-12-18 fl Added DPI read support (based on code by Niki Spahiev)
+# 2008-08-13 fl Added tRNS support for RGB images
+# 2009-03-06 fl Support for preserving ICC profiles (by Florian Hoech)
+# 2009-03-08 fl Added zTXT support (from Lowell Alleman)
+# 2009-03-29 fl Read interlaced PNG files (from Conrado Porto Lopes Gouvua)
+#
+# Copyright (c) 1997-2009 by Secret Labs AB
+# Copyright (c) 1996 by Fredrik Lundh
+#
+# See the README file for information on usage and redistribution.
+#
+
+from __future__ import print_function
+
+__version__ = "0.9"
+
+import re
+
+from PIL import Image, ImageFile, ImagePalette, _binary
+import zlib
+
+i8 = _binary.i8
+i16 = _binary.i16be
+i32 = _binary.i32be
+
+is_cid = re.compile(b"\w\w\w\w").match
+
+
+_MAGIC = b"\211PNG\r\n\032\n"
+
+
+_MODES = {
+ # supported bits/color combinations, and corresponding modes/rawmodes
+ (1, 0): ("1", "1"),
+ (2, 0): ("L", "L;2"),
+ (4, 0): ("L", "L;4"),
+ (8, 0): ("L", "L"),
+ (16, 0): ("I", "I;16B"),
+ (8, 2): ("RGB", "RGB"),
+ (16, 2): ("RGB", "RGB;16B"),
+ (1, 3): ("P", "P;1"),
+ (2, 3): ("P", "P;2"),
+ (4, 3): ("P", "P;4"),
+ (8, 3): ("P", "P"),
+ (8, 4): ("LA", "LA"),
+ (16, 4): ("RGBA", "LA;16B"), # LA;16B->LA not yet available
+ (8, 6): ("RGBA", "RGBA"),
+ (16, 6): ("RGBA", "RGBA;16B"),
+}
+
+
+_simple_palette = re.compile(b'^\xff+\x00\xff*$')
+
+# Maximum decompressed size for a iTXt or zTXt chunk.
+# Eliminates decompression bombs where compressed chunks can expand 1000x
+MAX_TEXT_CHUNK = ImageFile.SAFEBLOCK
+# Set the maximum total text chunk size.
+MAX_TEXT_MEMORY = 64 * MAX_TEXT_CHUNK
+
+def _safe_zlib_decompress(s):
+ dobj = zlib.decompressobj()
+ plaintext = dobj.decompress(s, MAX_TEXT_CHUNK)
+ if dobj.unconsumed_tail:
+ raise ValueError("Decompressed Data Too Large")
+ return plaintext
+
+
+# --------------------------------------------------------------------
+# Support classes. Suitable for PNG and related formats like MNG etc.
+
+class ChunkStream:
+
+ def __init__(self, fp):
+
+ self.fp = fp
+ self.queue = []
+
+ if not hasattr(Image.core, "crc32"):
+ self.crc = self.crc_skip
+
+ def read(self):
+ "Fetch a new chunk. Returns header information."
+
+ if self.queue:
+ cid, pos, length = self.queue[-1]
+ del self.queue[-1]
+ self.fp.seek(pos)
+ else:
+ s = self.fp.read(8)
+ cid = s[4:]
+ pos = self.fp.tell()
+ length = i32(s)
+
+ if not is_cid(cid):
+ raise SyntaxError("broken PNG file (chunk %s)" % repr(cid))
+
+ return cid, pos, length
+
+ def close(self):
+ self.queue = self.crc = self.fp = None
+
+ def push(self, cid, pos, length):
+
+ self.queue.append((cid, pos, length))
+
+ def call(self, cid, pos, length):
+ "Call the appropriate chunk handler"
+
+ if Image.DEBUG:
+ print("STREAM", cid, pos, length)
+ return getattr(self, "chunk_" + cid.decode('ascii'))(pos, length)
+
+ def crc(self, cid, data):
+ "Read and verify checksum"
+
+ crc1 = Image.core.crc32(data, Image.core.crc32(cid))
+ crc2 = i16(self.fp.read(2)), i16(self.fp.read(2))
+ if crc1 != crc2:
+ raise SyntaxError("broken PNG file"
+ "(bad header checksum in %s)" % cid)
+
+ def crc_skip(self, cid, data):
+ "Read checksum. Used if the C module is not present"
+
+ self.fp.read(4)
+
+ def verify(self, endchunk=b"IEND"):
+
+ # Simple approach; just calculate checksum for all remaining
+ # blocks. Must be called directly after open.
+
+ cids = []
+
+ while True:
+ cid, pos, length = self.read()
+ if cid == endchunk:
+ break
+ self.crc(cid, ImageFile._safe_read(self.fp, length))
+ cids.append(cid)
+
+ return cids
+
+
+class iTXt(str):
+ """
+ Subclass of string to allow iTXt chunks to look like strings while
+ keeping their extra information
+
+ """
+ @staticmethod
+ def __new__(cls, text, lang, tkey):
+ """
+ :param value: value for this key
+ :param lang: language code
+ :param tkey: UTF-8 version of the key name
+ """
+
+ self = str.__new__(cls, text)
+ self.lang = lang
+ self.tkey = tkey
+ return self
+
+
+class PngInfo:
+ """
+ PNG chunk container (for use with save(pnginfo=))
+
+ """
+
+ def __init__(self):
+ self.chunks = []
+
+ def add(self, cid, data):
+ """Appends an arbitrary chunk. Use with caution.
+
+ :param cid: a byte string, 4 bytes long.
+ :param data: a byte string of the encoded data
+
+ """
+
+ self.chunks.append((cid, data))
+
+ def add_itxt(self, key, value, lang="", tkey="", zip=False):
+ """Appends an iTXt chunk.
+
+ :param key: latin-1 encodable text key name
+ :param value: value for this key
+ :param lang: language code
+ :param tkey: UTF-8 version of the key name
+ :param zip: compression flag
+
+ """
+
+ 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:
+ 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):
+ """Appends a text chunk.
+
+ :param key: latin-1 encodable text key name
+ :param value: value for this key, text or an
+ :py:class:`PIL.PngImagePlugin.iTXt` instance
+ :param zip: compression flag
+
+ """
+ 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 zip:
+ self.add(b"zTXt", key + b"\0\0" + zlib.compress(value))
+ else:
+ self.add(b"tEXt", key + b"\0" + value)
+
+
+# --------------------------------------------------------------------
+# PNG image stream (IHDR/IEND)
+
+class PngStream(ChunkStream):
+
+ def __init__(self, fp):
+
+ ChunkStream.__init__(self, fp)
+
+ # local copies of Image attributes
+ self.im_info = {}
+ self.im_text = {}
+ self.im_size = (0, 0)
+ self.im_mode = None
+ self.im_tile = None
+ self.im_palette = None
+
+ self.text_memory = 0
+
+ def check_text_memory(self, chunklen):
+ self.text_memory += chunklen
+ if self.text_memory > MAX_TEXT_MEMORY:
+ raise ValueError("Too much memory used in text chunks: %s>MAX_TEXT_MEMORY" %
+ self.text_memory)
+
+ def chunk_iCCP(self, pos, length):
+
+ # ICC profile
+ s = ImageFile._safe_read(self.fp, length)
+ # according to PNG spec, the iCCP chunk contains:
+ # Profile name 1-79 bytes (character string)
+ # Null separator 1 byte (null character)
+ # Compression method 1 byte (0)
+ # Compressed profile n bytes (zlib with deflate compression)
+ i = s.find(b"\0")
+ if Image.DEBUG:
+ print("iCCP profile name", s[:i])
+ print("Compression method", i8(s[i]))
+ comp_method = i8(s[i])
+ if comp_method != 0:
+ raise SyntaxError("Unknown compression method %s in iCCP chunk" %
+ comp_method)
+ try:
+ icc_profile = _safe_zlib_decompress(s[i+2:])
+ except zlib.error:
+ icc_profile = None # FIXME
+ self.im_info["icc_profile"] = icc_profile
+ return s
+
+ def chunk_IHDR(self, pos, length):
+
+ # image header
+ s = ImageFile._safe_read(self.fp, length)
+ self.im_size = i32(s), i32(s[4:])
+ try:
+ self.im_mode, self.im_rawmode = _MODES[(i8(s[8]), i8(s[9]))]
+ except:
+ pass
+ if i8(s[12]):
+ self.im_info["interlace"] = 1
+ if i8(s[11]):
+ raise SyntaxError("unknown filter category")
+ return s
+
+ def chunk_IDAT(self, pos, length):
+
+ # image data
+ self.im_tile = [("zip", (0, 0)+self.im_size, pos, self.im_rawmode)]
+ self.im_idat = length
+ raise EOFError
+
+ def chunk_IEND(self, pos, length):
+
+ # end of PNG image
+ raise EOFError
+
+ def chunk_PLTE(self, pos, length):
+
+ # palette
+ s = ImageFile._safe_read(self.fp, length)
+ if self.im_mode == "P":
+ self.im_palette = "RGB", s
+ return s
+
+ def chunk_tRNS(self, pos, length):
+
+ # transparency
+ s = ImageFile._safe_read(self.fp, length)
+ if self.im_mode == "P":
+ if _simple_palette.match(s):
+ i = s.find(b"\0")
+ if i >= 0:
+ self.im_info["transparency"] = i
+ else:
+ self.im_info["transparency"] = s
+ elif self.im_mode == "L":
+ self.im_info["transparency"] = i16(s)
+ elif self.im_mode == "RGB":
+ self.im_info["transparency"] = i16(s), i16(s[2:]), i16(s[4:])
+ return s
+
+ def chunk_gAMA(self, pos, length):
+
+ # gamma setting
+ s = ImageFile._safe_read(self.fp, length)
+ self.im_info["gamma"] = i32(s) / 100000.0
+ return s
+
+ def chunk_pHYs(self, pos, length):
+
+ # pixels per unit
+ s = ImageFile._safe_read(self.fp, length)
+ px, py = i32(s), i32(s[4:])
+ unit = i8(s[8])
+ if unit == 1: # meter
+ dpi = int(px * 0.0254 + 0.5), int(py * 0.0254 + 0.5)
+ self.im_info["dpi"] = dpi
+ elif unit == 0:
+ self.im_info["aspect"] = px, py
+ return s
+
+ def chunk_tEXt(self, pos, length):
+
+ # text
+ s = ImageFile._safe_read(self.fp, length)
+ try:
+ k, v = s.split(b"\0", 1)
+ except ValueError:
+ # fallback for broken tEXt tags
+ k = s
+ v = b""
+ if k:
+ if bytes is not str:
+ k = k.decode('latin-1', 'strict')
+ v = v.decode('latin-1', 'replace')
+
+ self.im_info[k] = self.im_text[k] = v
+ self.check_text_memory(len(v))
+
+ return s
+
+ def chunk_zTXt(self, pos, length):
+
+ # compressed text
+ s = ImageFile._safe_read(self.fp, length)
+ try:
+ k, v = s.split(b"\0", 1)
+ except ValueError:
+ k = s
+ v = b""
+ if v:
+ comp_method = i8(v[0])
+ else:
+ comp_method = 0
+ if comp_method != 0:
+ raise SyntaxError("Unknown compression method %s in zTXt chunk" %
+ comp_method)
+ try:
+ v = _safe_zlib_decompress(v[1:])
+ except zlib.error:
+ v = b""
+
+ if k:
+ if bytes is not str:
+ k = k.decode('latin-1', 'strict')
+ v = v.decode('latin-1', 'replace')
+
+ self.im_info[k] = self.im_text[k] = v
+ self.check_text_memory(len(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:
+ try:
+ v = _safe_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)
+ self.check_text_memory(len(v))
+
+ return s
+
+
+# --------------------------------------------------------------------
+# PNG reader
+
+def _accept(prefix):
+ return prefix[:8] == _MAGIC
+
+
+##
+# Image plugin for PNG images.
+
+class PngImageFile(ImageFile.ImageFile):
+
+ format = "PNG"
+ format_description = "Portable network graphics"
+
+ def _open(self):
+
+ if self.fp.read(8) != _MAGIC:
+ raise SyntaxError("not a PNG file")
+
+ #
+ # Parse headers up to the first IDAT chunk
+
+ self.png = PngStream(self.fp)
+
+ while True:
+
+ #
+ # get next chunk
+
+ cid, pos, length = self.png.read()
+
+ try:
+ s = self.png.call(cid, pos, length)
+ except EOFError:
+ break
+ except AttributeError:
+ if Image.DEBUG:
+ print(cid, pos, length, "(unknown)")
+ s = ImageFile._safe_read(self.fp, length)
+
+ self.png.crc(cid, s)
+
+ #
+ # Copy relevant attributes from the PngStream. An alternative
+ # would be to let the PngStream class modify these attributes
+ # directly, but that introduces circular references which are
+ # difficult to break if things go wrong in the decoder...
+ # (believe me, I've tried ;-)
+
+ self.mode = self.png.im_mode
+ self.size = self.png.im_size
+ self.info = self.png.im_info
+ self.text = self.png.im_text # experimental
+ self.tile = self.png.im_tile
+
+ if self.png.im_palette:
+ rawmode, data = self.png.im_palette
+ self.palette = ImagePalette.raw(rawmode, data)
+
+ self.__idat = length # used by load_read()
+
+ def verify(self):
+ "Verify PNG file"
+
+ if self.fp is None:
+ raise RuntimeError("verify must be called directly after open")
+
+ # back up to beginning of IDAT block
+ self.fp.seek(self.tile[0][2] - 8)
+
+ self.png.verify()
+ self.png.close()
+
+ self.fp = None
+
+ def load_prepare(self):
+ "internal: prepare to read PNG file"
+
+ if self.info.get("interlace"):
+ self.decoderconfig = self.decoderconfig + (1,)
+
+ ImageFile.ImageFile.load_prepare(self)
+
+ def load_read(self, read_bytes):
+ "internal: read more image data"
+
+ while self.__idat == 0:
+ # end of chunk, skip forward to next one
+
+ self.fp.read(4) # CRC
+
+ cid, pos, length = self.png.read()
+
+ if cid not in [b"IDAT", b"DDAT"]:
+ self.png.push(cid, pos, length)
+ return b""
+
+ self.__idat = length # empty chunks are allowed
+
+ # read more data from this chunk
+ if read_bytes <= 0:
+ read_bytes = self.__idat
+ else:
+ read_bytes = min(read_bytes, self.__idat)
+
+ self.__idat = self.__idat - read_bytes
+
+ return self.fp.read(read_bytes)
+
+ def load_end(self):
+ "internal: finished reading image data"
+
+ self.png.close()
+ self.png = None
+
+
+# --------------------------------------------------------------------
+# PNG writer
+
+o8 = _binary.o8
+o16 = _binary.o16be
+o32 = _binary.o32be
+
+_OUTMODES = {
+ # supported PIL modes, and corresponding rawmodes/bits/color combinations
+ "1": ("1", b'\x01\x00'),
+ "L;1": ("L;1", b'\x01\x00'),
+ "L;2": ("L;2", b'\x02\x00'),
+ "L;4": ("L;4", b'\x04\x00'),
+ "L": ("L", b'\x08\x00'),
+ "LA": ("LA", b'\x08\x04'),
+ "I": ("I;16B", b'\x10\x00'),
+ "P;1": ("P;1", b'\x01\x03'),
+ "P;2": ("P;2", b'\x02\x03'),
+ "P;4": ("P;4", b'\x04\x03'),
+ "P": ("P", b'\x08\x03'),
+ "RGB": ("RGB", b'\x08\x02'),
+ "RGBA": ("RGBA", b'\x08\x06'),
+}
+
+
+def putchunk(fp, cid, *data):
+ "Write a PNG chunk (including CRC field)"
+
+ data = b"".join(data)
+
+ fp.write(o32(len(data)) + cid)
+ fp.write(data)
+ hi, lo = Image.core.crc32(data, Image.core.crc32(cid))
+ fp.write(o16(hi) + o16(lo))
+
+
+class _idat:
+ # wrap output from the encoder in IDAT chunks
+
+ def __init__(self, fp, chunk):
+ self.fp = fp
+ self.chunk = chunk
+
+ def write(self, data):
+ self.chunk(self.fp, b"IDAT", data)
+
+
+def _save(im, fp, filename, chunk=putchunk, check=0):
+ # save an image to disk (called by the save method)
+
+ mode = im.mode
+
+ if mode == "P":
+
+ #
+ # attempt to minimize storage requirements for palette images
+ if "bits" in im.encoderinfo:
+ # number of bits specified by user
+ colors = 1 << im.encoderinfo["bits"]
+ else:
+ # check palette contents
+ if im.palette:
+ colors = max(min(len(im.palette.getdata()[1])//3, 256), 2)
+ else:
+ colors = 256
+
+ if colors <= 2:
+ bits = 1
+ elif colors <= 4:
+ bits = 2
+ elif colors <= 16:
+ bits = 4
+ else:
+ bits = 8
+ if bits != 8:
+ mode = "%s;%d" % (mode, bits)
+
+ # encoder options
+ if "dictionary" in im.encoderinfo:
+ dictionary = im.encoderinfo["dictionary"]
+ else:
+ dictionary = b""
+
+ im.encoderconfig = ("optimize" in im.encoderinfo,
+ im.encoderinfo.get("compress_level", -1),
+ im.encoderinfo.get("compress_type", -1),
+ dictionary)
+
+ # get the corresponding PNG mode
+ try:
+ rawmode, mode = _OUTMODES[mode]
+ except KeyError:
+ raise IOError("cannot write mode %s as PNG" % mode)
+
+ if check:
+ return check
+
+ #
+ # write minimal PNG file
+
+ fp.write(_MAGIC)
+
+ chunk(fp, b"IHDR",
+ o32(im.size[0]), o32(im.size[1]), # 0: size
+ mode, # 8: depth/type
+ b'\0', # 10: compression
+ b'\0', # 11: filter category
+ b'\0') # 12: interlace flag
+
+ if im.mode == "P":
+ palette_byte_number = (2 ** bits) * 3
+ palette_bytes = im.im.getpalette("RGB")[:palette_byte_number]
+ while len(palette_bytes) < palette_byte_number:
+ palette_bytes += b'\0'
+ chunk(fp, b"PLTE", palette_bytes)
+
+ transparency = im.encoderinfo.get('transparency',
+ im.info.get('transparency', None))
+
+ if transparency or transparency == 0:
+ if im.mode == "P":
+ # limit to actual palette size
+ alpha_bytes = 2**bits
+ if isinstance(transparency, bytes):
+ chunk(fp, b"tRNS", transparency[:alpha_bytes])
+ else:
+ transparency = max(0, min(255, transparency))
+ alpha = b'\xFF' * transparency + b'\0'
+ chunk(fp, b"tRNS", alpha[:alpha_bytes])
+ elif im.mode == "L":
+ transparency = max(0, min(65535, transparency))
+ chunk(fp, b"tRNS", o16(transparency))
+ elif im.mode == "RGB":
+ red, green, blue = transparency
+ chunk(fp, b"tRNS", o16(red) + o16(green) + o16(blue))
+ else:
+ if "transparency" in im.encoderinfo:
+ # don't bother with transparency if it's an RGBA
+ # and it's in the info dict. It's probably just stale.
+ raise IOError("cannot use transparency for this mode")
+ else:
+ if im.mode == "P" and im.im.getpalettemode() == "RGBA":
+ alpha = im.im.getpalette("RGBA", "A")
+ alpha_bytes = 2**bits
+ chunk(fp, b"tRNS", alpha[:alpha_bytes])
+
+ dpi = im.encoderinfo.get("dpi")
+ if dpi:
+ chunk(fp, b"pHYs",
+ o32(int(dpi[0] / 0.0254 + 0.5)),
+ o32(int(dpi[1] / 0.0254 + 0.5)),
+ b'\x01')
+
+ info = im.encoderinfo.get("pnginfo")
+ if info:
+ for cid, data in info.chunks:
+ chunk(fp, cid, data)
+
+ # ICC profile writing support -- 2008-06-06 Florian Hoech
+ if im.info.get("icc_profile"):
+ # ICC profile
+ # according to PNG spec, the iCCP chunk contains:
+ # Profile name 1-79 bytes (character string)
+ # Null separator 1 byte (null character)
+ # Compression method 1 byte (0)
+ # Compressed profile n bytes (zlib with deflate compression)
+ name = b"ICC Profile"
+ data = name + b"\0\0" + zlib.compress(im.info["icc_profile"])
+ chunk(fp, b"iCCP", data)
+
+ ImageFile._save(im, _idat(fp, chunk),
+ [("zip", (0, 0)+im.size, 0, rawmode)])
+
+ chunk(fp, b"IEND", b"")
+
+ try:
+ fp.flush()
+ except:
+ pass
+
+
+# --------------------------------------------------------------------
+# PNG chunk converter
+
+def getchunks(im, **params):
+ """Return a list of PNG chunks representing this image."""
+
+ class collector:
+ data = []
+
+ def write(self, data):
+ pass
+
+ def append(self, chunk):
+ self.data.append(chunk)
+
+ def append(fp, cid, *data):
+ data = b"".join(data)
+ hi, lo = Image.core.crc32(data, Image.core.crc32(cid))
+ crc = o16(hi) + o16(lo)
+ fp.append((cid, data, crc))
+
+ fp = collector()
+
+ try:
+ im.encoderinfo = params
+ _save(im, fp, None, append)
+ finally:
+ del im.encoderinfo
+
+ return fp.data
+
+
+# --------------------------------------------------------------------
+# Registry
+
+Image.register_open("PNG", PngImageFile, _accept)
+Image.register_save("PNG", _save)
+
+Image.register_extension("PNG", ".png")
+
+Image.register_mime("PNG", "image/png")