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https://github.com/python-pillow/Pillow.git
synced 2024-09-21 11:28:58 +03:00
416d8e340e
When saving a JPEG and specifying 'keep' for quality or subsampling, if the source JPEG image is in grayscale mode, don't try to find the subsampling of the source, because grayscale images don't have any subsampling (it's only for color components). For the moment the fix also ignores subsampling of CMYK JPEG because currently Pillow doesn't support encoding JPEG in YCCK mode (and subsampling doesn't make sense in CMYK, but Pillow permits saving CMYK JPEG with subsampling, that's a bug). This fix pass those errors silently, i.e. it doesn't raise an error when 'keep' is used but it's not possible to keep the subsampling (because the image is grayscale or CMYK). I think it's the proper behavior but I'm not sure.
731 lines
24 KiB
Python
731 lines
24 KiB
Python
#
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# The Python Imaging Library.
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# $Id$
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#
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# JPEG (JFIF) file handling
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#
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# See "Digital Compression and Coding of Continous-Tone Still Images,
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# Part 1, Requirements and Guidelines" (CCITT T.81 / ISO 10918-1)
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#
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# History:
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# 1995-09-09 fl Created
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# 1995-09-13 fl Added full parser
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# 1996-03-25 fl Added hack to use the IJG command line utilities
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# 1996-05-05 fl Workaround Photoshop 2.5 CMYK polarity bug
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# 1996-05-28 fl Added draft support, JFIF version (0.1)
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# 1996-12-30 fl Added encoder options, added progression property (0.2)
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# 1997-08-27 fl Save mode 1 images as BW (0.3)
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# 1998-07-12 fl Added YCbCr to draft and save methods (0.4)
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# 1998-10-19 fl Don't hang on files using 16-bit DQT's (0.4.1)
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# 2001-04-16 fl Extract DPI settings from JFIF files (0.4.2)
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# 2002-07-01 fl Skip pad bytes before markers; identify Exif files (0.4.3)
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# 2003-04-25 fl Added experimental EXIF decoder (0.5)
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# 2003-06-06 fl Added experimental EXIF GPSinfo decoder
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# 2003-09-13 fl Extract COM markers
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# 2009-09-06 fl Added icc_profile support (from Florian Hoech)
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# 2009-03-06 fl Changed CMYK handling; always use Adobe polarity (0.6)
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# 2009-03-08 fl Added subsampling support (from Justin Huff).
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#
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# Copyright (c) 1997-2003 by Secret Labs AB.
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# Copyright (c) 1995-1996 by Fredrik Lundh.
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#
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# See the README file for information on usage and redistribution.
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#
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__version__ = "0.6"
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import array
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import struct
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import io
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from struct import unpack
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from PIL import Image, ImageFile, TiffImagePlugin, _binary
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from PIL.JpegPresets import presets
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from PIL._util import isStringType
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i8 = _binary.i8
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o8 = _binary.o8
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i16 = _binary.i16be
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i32 = _binary.i32be
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#
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# Parser
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def Skip(self, marker):
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n = i16(self.fp.read(2))-2
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ImageFile._safe_read(self.fp, n)
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def APP(self, marker):
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#
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# Application marker. Store these in the APP dictionary.
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# Also look for well-known application markers.
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n = i16(self.fp.read(2))-2
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s = ImageFile._safe_read(self.fp, n)
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app = "APP%d" % (marker & 15)
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self.app[app] = s # compatibility
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self.applist.append((app, s))
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if marker == 0xFFE0 and s[:4] == b"JFIF":
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# extract JFIF information
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self.info["jfif"] = version = i16(s, 5) # version
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self.info["jfif_version"] = divmod(version, 256)
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# extract JFIF properties
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try:
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jfif_unit = i8(s[7])
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jfif_density = i16(s, 8), i16(s, 10)
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except:
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pass
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else:
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if jfif_unit == 1:
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self.info["dpi"] = jfif_density
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self.info["jfif_unit"] = jfif_unit
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self.info["jfif_density"] = jfif_density
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elif marker == 0xFFE1 and s[:5] == b"Exif\0":
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# extract Exif information (incomplete)
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self.info["exif"] = s # FIXME: value will change
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elif marker == 0xFFE2 and s[:5] == b"FPXR\0":
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# extract FlashPix information (incomplete)
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self.info["flashpix"] = s # FIXME: value will change
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elif marker == 0xFFE2 and s[:12] == b"ICC_PROFILE\0":
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# Since an ICC profile can be larger than the maximum size of
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# a JPEG marker (64K), we need provisions to split it into
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# multiple markers. The format defined by the ICC specifies
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# one or more APP2 markers containing the following data:
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# Identifying string ASCII "ICC_PROFILE\0" (12 bytes)
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# Marker sequence number 1, 2, etc (1 byte)
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# Number of markers Total of APP2's used (1 byte)
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# Profile data (remainder of APP2 data)
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# Decoders should use the marker sequence numbers to
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# reassemble the profile, rather than assuming that the APP2
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# markers appear in the correct sequence.
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self.icclist.append(s)
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elif marker == 0xFFEE and s[:5] == b"Adobe":
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self.info["adobe"] = i16(s, 5)
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# extract Adobe custom properties
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try:
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adobe_transform = i8(s[1])
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except:
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pass
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else:
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self.info["adobe_transform"] = adobe_transform
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elif marker == 0xFFE2 and s[:4] == b"MPF\0":
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# extract MPO information
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self.info["mp"] = s[4:]
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# offset is current location minus buffer size plus constant header size
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self.info["mpoffset"] = self.fp.tell() - n + 4
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def COM(self, marker):
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#
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# Comment marker. Store these in the APP dictionary.
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n = i16(self.fp.read(2))-2
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s = ImageFile._safe_read(self.fp, n)
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self.app["COM"] = s # compatibility
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self.applist.append(("COM", s))
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def SOF(self, marker):
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#
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# Start of frame marker. Defines the size and mode of the
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# image. JPEG is colour blind, so we use some simple
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# heuristics to map the number of layers to an appropriate
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# mode. Note that this could be made a bit brighter, by
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# looking for JFIF and Adobe APP markers.
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n = i16(self.fp.read(2))-2
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s = ImageFile._safe_read(self.fp, n)
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self.size = i16(s[3:]), i16(s[1:])
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self.bits = i8(s[0])
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if self.bits != 8:
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raise SyntaxError("cannot handle %d-bit layers" % self.bits)
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self.layers = i8(s[5])
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if self.layers == 1:
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self.mode = "L"
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elif self.layers == 3:
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self.mode = "RGB"
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elif self.layers == 4:
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self.mode = "CMYK"
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else:
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raise SyntaxError("cannot handle %d-layer images" % self.layers)
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if marker in [0xFFC2, 0xFFC6, 0xFFCA, 0xFFCE]:
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self.info["progressive"] = self.info["progression"] = 1
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if self.icclist:
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# fixup icc profile
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self.icclist.sort() # sort by sequence number
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if i8(self.icclist[0][13]) == len(self.icclist):
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profile = []
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for p in self.icclist:
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profile.append(p[14:])
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icc_profile = b"".join(profile)
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else:
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icc_profile = None # wrong number of fragments
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self.info["icc_profile"] = icc_profile
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self.icclist = None
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for i in range(6, len(s), 3):
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t = s[i:i+3]
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# 4-tuples: id, vsamp, hsamp, qtable
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self.layer.append((t[0], i8(t[1])//16, i8(t[1]) & 15, i8(t[2])))
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def DQT(self, marker):
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#
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# Define quantization table. Support baseline 8-bit tables
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# only. Note that there might be more than one table in
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# each marker.
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# FIXME: The quantization tables can be used to estimate the
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# compression quality.
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n = i16(self.fp.read(2))-2
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s = ImageFile._safe_read(self.fp, n)
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while len(s):
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if len(s) < 65:
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raise SyntaxError("bad quantization table marker")
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v = i8(s[0])
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if v//16 == 0:
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self.quantization[v & 15] = array.array("b", s[1:65])
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s = s[65:]
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else:
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return # FIXME: add code to read 16-bit tables!
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# raise SyntaxError, "bad quantization table element size"
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#
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# JPEG marker table
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MARKER = {
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0xFFC0: ("SOF0", "Baseline DCT", SOF),
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0xFFC1: ("SOF1", "Extended Sequential DCT", SOF),
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0xFFC2: ("SOF2", "Progressive DCT", SOF),
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0xFFC3: ("SOF3", "Spatial lossless", SOF),
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0xFFC4: ("DHT", "Define Huffman table", Skip),
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0xFFC5: ("SOF5", "Differential sequential DCT", SOF),
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0xFFC6: ("SOF6", "Differential progressive DCT", SOF),
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0xFFC7: ("SOF7", "Differential spatial", SOF),
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0xFFC8: ("JPG", "Extension", None),
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0xFFC9: ("SOF9", "Extended sequential DCT (AC)", SOF),
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0xFFCA: ("SOF10", "Progressive DCT (AC)", SOF),
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0xFFCB: ("SOF11", "Spatial lossless DCT (AC)", SOF),
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0xFFCC: ("DAC", "Define arithmetic coding conditioning", Skip),
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0xFFCD: ("SOF13", "Differential sequential DCT (AC)", SOF),
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0xFFCE: ("SOF14", "Differential progressive DCT (AC)", SOF),
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0xFFCF: ("SOF15", "Differential spatial (AC)", SOF),
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0xFFD0: ("RST0", "Restart 0", None),
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0xFFD1: ("RST1", "Restart 1", None),
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0xFFD2: ("RST2", "Restart 2", None),
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0xFFD3: ("RST3", "Restart 3", None),
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0xFFD4: ("RST4", "Restart 4", None),
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0xFFD5: ("RST5", "Restart 5", None),
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0xFFD6: ("RST6", "Restart 6", None),
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0xFFD7: ("RST7", "Restart 7", None),
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0xFFD8: ("SOI", "Start of image", None),
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0xFFD9: ("EOI", "End of image", None),
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0xFFDA: ("SOS", "Start of scan", Skip),
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0xFFDB: ("DQT", "Define quantization table", DQT),
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0xFFDC: ("DNL", "Define number of lines", Skip),
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0xFFDD: ("DRI", "Define restart interval", Skip),
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0xFFDE: ("DHP", "Define hierarchical progression", SOF),
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0xFFDF: ("EXP", "Expand reference component", Skip),
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0xFFE0: ("APP0", "Application segment 0", APP),
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0xFFE1: ("APP1", "Application segment 1", APP),
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0xFFE2: ("APP2", "Application segment 2", APP),
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0xFFE3: ("APP3", "Application segment 3", APP),
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0xFFE4: ("APP4", "Application segment 4", APP),
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0xFFE5: ("APP5", "Application segment 5", APP),
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0xFFE6: ("APP6", "Application segment 6", APP),
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0xFFE7: ("APP7", "Application segment 7", APP),
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0xFFE8: ("APP8", "Application segment 8", APP),
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0xFFE9: ("APP9", "Application segment 9", APP),
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0xFFEA: ("APP10", "Application segment 10", APP),
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0xFFEB: ("APP11", "Application segment 11", APP),
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0xFFEC: ("APP12", "Application segment 12", APP),
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0xFFED: ("APP13", "Application segment 13", APP),
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0xFFEE: ("APP14", "Application segment 14", APP),
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0xFFEF: ("APP15", "Application segment 15", APP),
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0xFFF0: ("JPG0", "Extension 0", None),
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0xFFF1: ("JPG1", "Extension 1", None),
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0xFFF2: ("JPG2", "Extension 2", None),
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0xFFF3: ("JPG3", "Extension 3", None),
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0xFFF4: ("JPG4", "Extension 4", None),
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0xFFF5: ("JPG5", "Extension 5", None),
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0xFFF6: ("JPG6", "Extension 6", None),
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0xFFF7: ("JPG7", "Extension 7", None),
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0xFFF8: ("JPG8", "Extension 8", None),
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0xFFF9: ("JPG9", "Extension 9", None),
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0xFFFA: ("JPG10", "Extension 10", None),
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0xFFFB: ("JPG11", "Extension 11", None),
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0xFFFC: ("JPG12", "Extension 12", None),
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0xFFFD: ("JPG13", "Extension 13", None),
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0xFFFE: ("COM", "Comment", COM)
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}
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def _accept(prefix):
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return prefix[0:1] == b"\377"
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##
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# Image plugin for JPEG and JFIF images.
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class JpegImageFile(ImageFile.ImageFile):
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format = "JPEG"
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format_description = "JPEG (ISO 10918)"
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def _open(self):
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s = self.fp.read(1)
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if i8(s[0]) != 255:
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raise SyntaxError("not a JPEG file")
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# Create attributes
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self.bits = self.layers = 0
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# JPEG specifics (internal)
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self.layer = []
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self.huffman_dc = {}
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self.huffman_ac = {}
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self.quantization = {}
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self.app = {} # compatibility
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self.applist = []
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self.icclist = []
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while True:
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i = i8(s)
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if i == 0xFF:
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s = s + self.fp.read(1)
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i = i16(s)
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else:
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# Skip non-0xFF junk
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s = b"\xff"
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continue
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if i in MARKER:
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name, description, handler = MARKER[i]
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# print hex(i), name, description
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if handler is not None:
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handler(self, i)
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if i == 0xFFDA: # start of scan
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rawmode = self.mode
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if self.mode == "CMYK":
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rawmode = "CMYK;I" # assume adobe conventions
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self.tile = [("jpeg", (0, 0) + self.size, 0, (rawmode, ""))]
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# self.__offset = self.fp.tell()
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break
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s = self.fp.read(1)
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elif i == 0 or i == 0xFFFF:
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# padded marker or junk; move on
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s = b"\xff"
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else:
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raise SyntaxError("no marker found")
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def draft(self, mode, size):
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if len(self.tile) != 1:
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return
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d, e, o, a = self.tile[0]
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scale = 0
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if a[0] == "RGB" and mode in ["L", "YCbCr"]:
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self.mode = mode
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a = mode, ""
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if size:
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scale = max(self.size[0] // size[0], self.size[1] // size[1])
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for s in [8, 4, 2, 1]:
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if scale >= s:
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break
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e = e[0], e[1], (e[2]-e[0]+s-1)//s+e[0], (e[3]-e[1]+s-1)//s+e[1]
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self.size = ((self.size[0]+s-1)//s, (self.size[1]+s-1)//s)
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scale = s
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self.tile = [(d, e, o, a)]
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self.decoderconfig = (scale, 1)
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return self
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def load_djpeg(self):
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# ALTERNATIVE: handle JPEGs via the IJG command line utilities
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import subprocess
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import tempfile
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import os
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f, path = tempfile.mkstemp()
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os.close(f)
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if os.path.exists(self.filename):
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subprocess.check_call(["djpeg", "-outfile", path, self.filename])
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else:
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raise ValueError("Invalid Filename")
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try:
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self.im = Image.core.open_ppm(path)
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finally:
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try:
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os.unlink(path)
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except:
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pass
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self.mode = self.im.mode
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self.size = self.im.size
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self.tile = []
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def _getexif(self):
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return _getexif(self)
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def _getmp(self):
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return _getmp(self)
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def _fixup(value):
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# Helper function for _getexif() and _getmp()
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if len(value) == 1:
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return value[0]
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return value
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def _getexif(self):
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# Extract EXIF information. This method is highly experimental,
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# and is likely to be replaced with something better in a future
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# version.
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# The EXIF record consists of a TIFF file embedded in a JPEG
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# application marker (!).
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try:
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data = self.info["exif"]
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except KeyError:
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return None
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file = io.BytesIO(data[6:])
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head = file.read(8)
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exif = {}
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# process dictionary
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info = TiffImagePlugin.ImageFileDirectory(head)
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info.load(file)
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for key, value in info.items():
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exif[key] = _fixup(value)
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# get exif extension
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try:
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file.seek(exif[0x8769])
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except KeyError:
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pass
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else:
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info = TiffImagePlugin.ImageFileDirectory(head)
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info.load(file)
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for key, value in info.items():
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exif[key] = _fixup(value)
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# get gpsinfo extension
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try:
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file.seek(exif[0x8825])
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except KeyError:
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pass
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else:
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info = TiffImagePlugin.ImageFileDirectory(head)
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info.load(file)
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exif[0x8825] = gps = {}
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for key, value in info.items():
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gps[key] = _fixup(value)
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return exif
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|
|
|
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def _getmp(self):
|
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# Extract MP information. This method was inspired by the "highly
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# experimental" _getexif version that's been in use for years now,
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# itself based on the ImageFileDirectory class in the TIFF plug-in.
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|
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# The MP record essentially consists of a TIFF file embedded in a JPEG
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# application marker.
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try:
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data = self.info["mp"]
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except KeyError:
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return None
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file = io.BytesIO(data)
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head = file.read(8)
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endianness = '>' if head[:4] == b'\x4d\x4d\x00\x2a' else '<'
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mp = {}
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# process dictionary
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info = TiffImagePlugin.ImageFileDirectory(head)
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info.load(file)
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for key, value in info.items():
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mp[key] = _fixup(value)
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# it's an error not to have a number of images
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try:
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quant = mp[0xB001]
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except KeyError:
|
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raise SyntaxError("malformed MP Index (no number of images)")
|
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# get MP entries
|
|
try:
|
|
mpentries = []
|
|
for entrynum in range(0, quant):
|
|
rawmpentry = mp[0xB002][entrynum * 16:(entrynum + 1) * 16]
|
|
unpackedentry = unpack('{0}LLLHH'.format(endianness), rawmpentry)
|
|
labels = ('Attribute', 'Size', 'DataOffset', 'EntryNo1', 'EntryNo2')
|
|
mpentry = dict(zip(labels, unpackedentry))
|
|
mpentryattr = {
|
|
'DependentParentImageFlag': bool(mpentry['Attribute'] & (1<<31)),
|
|
'DependentChildImageFlag': bool(mpentry['Attribute'] & (1<<30)),
|
|
'RepresentativeImageFlag': bool(mpentry['Attribute'] & (1<<29)),
|
|
'Reserved': (mpentry['Attribute'] & (3<<27)) >> 27,
|
|
'ImageDataFormat': (mpentry['Attribute'] & (7<<24)) >> 24,
|
|
'MPType': mpentry['Attribute'] & 0x00FFFFFF
|
|
}
|
|
if mpentryattr['ImageDataFormat'] == 0:
|
|
mpentryattr['ImageDataFormat'] = 'JPEG'
|
|
else:
|
|
raise SyntaxError("unsupported picture format in MPO")
|
|
mptypemap = {
|
|
0x000000: 'Undefined',
|
|
0x010001: 'Large Thumbnail (VGA Equivalent)',
|
|
0x010002: 'Large Thumbnail (Full HD Equivalent)',
|
|
0x020001: 'Multi-Frame Image (Panorama)',
|
|
0x020002: 'Multi-Frame Image: (Disparity)',
|
|
0x020003: 'Multi-Frame Image: (Multi-Angle)',
|
|
0x030000: 'Baseline MP Primary Image'
|
|
}
|
|
mpentryattr['MPType'] = mptypemap.get(mpentryattr['MPType'],
|
|
'Unknown')
|
|
mpentry['Attribute'] = mpentryattr
|
|
mpentries.append(mpentry)
|
|
mp[0xB002] = mpentries
|
|
except KeyError:
|
|
raise SyntaxError("malformed MP Index (bad MP Entry)")
|
|
# Next we should try and parse the individual image unique ID list;
|
|
# we don't because I've never seen this actually used in a real MPO
|
|
# file and so can't test it.
|
|
return mp
|
|
|
|
|
|
# --------------------------------------------------------------------
|
|
# stuff to save JPEG files
|
|
|
|
RAWMODE = {
|
|
"1": "L",
|
|
"L": "L",
|
|
"RGB": "RGB",
|
|
"RGBA": "RGB",
|
|
"RGBX": "RGB",
|
|
"CMYK": "CMYK;I", # assume adobe conventions
|
|
"YCbCr": "YCbCr",
|
|
}
|
|
|
|
zigzag_index = ( 0, 1, 5, 6, 14, 15, 27, 28,
|
|
2, 4, 7, 13, 16, 26, 29, 42,
|
|
3, 8, 12, 17, 25, 30, 41, 43,
|
|
9, 11, 18, 24, 31, 40, 44, 53,
|
|
10, 19, 23, 32, 39, 45, 52, 54,
|
|
20, 22, 33, 38, 46, 51, 55, 60,
|
|
21, 34, 37, 47, 50, 56, 59, 61,
|
|
35, 36, 48, 49, 57, 58, 62, 63)
|
|
|
|
samplings = {
|
|
(1, 1, 1, 1, 1, 1): 0,
|
|
(2, 1, 1, 1, 1, 1): 1,
|
|
(2, 2, 1, 1, 1, 1): 2,
|
|
}
|
|
|
|
|
|
def convert_dict_qtables(qtables):
|
|
qtables = [qtables[key] for key in range(len(qtables)) if key in qtables]
|
|
for idx, table in enumerate(qtables):
|
|
qtables[idx] = [table[i] for i in zigzag_index]
|
|
return qtables
|
|
|
|
|
|
def get_sampling(im):
|
|
# There's no subsampling when image have only 1 layer
|
|
# (grayscale images) or when they are CMYK (4 layers),
|
|
# so set subsampling to default value.
|
|
#
|
|
# NOTE: currently Pillow can't encode JPEG to YCCK format.
|
|
# If YCCK support is added in the future, subsampling code will have
|
|
# to be updated (here and in JpegEncode.c) to deal with 4 layers.
|
|
if not hasattr(im, 'layers') or im.layers in (1, 4):
|
|
return -1
|
|
sampling = im.layer[0][1:3] + im.layer[1][1:3] + im.layer[2][1:3]
|
|
return samplings.get(sampling, -1)
|
|
|
|
|
|
def _save(im, fp, filename):
|
|
|
|
try:
|
|
rawmode = RAWMODE[im.mode]
|
|
except KeyError:
|
|
raise IOError("cannot write mode %s as JPEG" % im.mode)
|
|
|
|
info = im.encoderinfo
|
|
|
|
dpi = info.get("dpi", (0, 0))
|
|
|
|
quality = info.get("quality", 0)
|
|
subsampling = info.get("subsampling", -1)
|
|
qtables = info.get("qtables")
|
|
|
|
if quality == "keep":
|
|
quality = 0
|
|
subsampling = "keep"
|
|
qtables = "keep"
|
|
elif quality in presets:
|
|
preset = presets[quality]
|
|
quality = 0
|
|
subsampling = preset.get('subsampling', -1)
|
|
qtables = preset.get('quantization')
|
|
elif not isinstance(quality, int):
|
|
raise ValueError("Invalid quality setting")
|
|
else:
|
|
if subsampling in presets:
|
|
subsampling = presets[subsampling].get('subsampling', -1)
|
|
if isStringType(qtables) and qtables in presets:
|
|
qtables = presets[qtables].get('quantization')
|
|
|
|
if subsampling == "4:4:4":
|
|
subsampling = 0
|
|
elif subsampling == "4:2:2":
|
|
subsampling = 1
|
|
elif subsampling == "4:1:1":
|
|
subsampling = 2
|
|
elif subsampling == "keep":
|
|
if im.format != "JPEG":
|
|
raise ValueError("Cannot use 'keep' when original image is not a JPEG")
|
|
subsampling = get_sampling(im)
|
|
|
|
def validate_qtables(qtables):
|
|
if qtables is None:
|
|
return qtables
|
|
if isStringType(qtables):
|
|
try:
|
|
lines = [int(num) for line in qtables.splitlines()
|
|
for num in line.split('#', 1)[0].split()]
|
|
except ValueError:
|
|
raise ValueError("Invalid quantization table")
|
|
else:
|
|
qtables = [lines[s:s+64] for s in range(0, len(lines), 64)]
|
|
if isinstance(qtables, (tuple, list, dict)):
|
|
if isinstance(qtables, dict):
|
|
qtables = convert_dict_qtables(qtables)
|
|
elif isinstance(qtables, tuple):
|
|
qtables = list(qtables)
|
|
if not (0 < len(qtables) < 5):
|
|
raise ValueError("None or too many quantization tables")
|
|
for idx, table in enumerate(qtables):
|
|
try:
|
|
if len(table) != 64:
|
|
raise
|
|
table = array.array('b', table)
|
|
except TypeError:
|
|
raise ValueError("Invalid quantization table")
|
|
else:
|
|
qtables[idx] = list(table)
|
|
return qtables
|
|
|
|
if qtables == "keep":
|
|
if im.format != "JPEG":
|
|
raise ValueError("Cannot use 'keep' when original image is not a JPEG")
|
|
qtables = getattr(im, "quantization", None)
|
|
qtables = validate_qtables(qtables)
|
|
|
|
extra = b""
|
|
|
|
icc_profile = info.get("icc_profile")
|
|
if icc_profile:
|
|
ICC_OVERHEAD_LEN = 14
|
|
MAX_BYTES_IN_MARKER = 65533
|
|
MAX_DATA_BYTES_IN_MARKER = MAX_BYTES_IN_MARKER - ICC_OVERHEAD_LEN
|
|
markers = []
|
|
while icc_profile:
|
|
markers.append(icc_profile[:MAX_DATA_BYTES_IN_MARKER])
|
|
icc_profile = icc_profile[MAX_DATA_BYTES_IN_MARKER:]
|
|
i = 1
|
|
for marker in markers:
|
|
size = struct.pack(">H", 2 + ICC_OVERHEAD_LEN + len(marker))
|
|
extra += b"\xFF\xE2" + size + b"ICC_PROFILE\0" + o8(i) + o8(len(markers)) + marker
|
|
i += 1
|
|
|
|
# get keyword arguments
|
|
im.encoderconfig = (
|
|
quality,
|
|
# "progressive" is the official name, but older documentation
|
|
# says "progression"
|
|
# FIXME: issue a warning if the wrong form is used (post-1.1.7)
|
|
"progressive" in info or "progression" in info,
|
|
info.get("smooth", 0),
|
|
"optimize" in info,
|
|
info.get("streamtype", 0),
|
|
dpi[0], dpi[1],
|
|
subsampling,
|
|
qtables,
|
|
extra,
|
|
info.get("exif", b"")
|
|
)
|
|
|
|
# if we optimize, libjpeg needs a buffer big enough to hold the whole image
|
|
# in a shot. Guessing on the size, at im.size bytes. (raw pizel size is
|
|
# channels*size, this is a value that's been used in a django patch.
|
|
# https://github.com/jdriscoll/django-imagekit/issues/50
|
|
bufsize = 0
|
|
if "optimize" in info or "progressive" in info or "progression" in info:
|
|
if quality >= 95:
|
|
bufsize = 2 * im.size[0] * im.size[1]
|
|
else:
|
|
bufsize = im.size[0] * im.size[1]
|
|
|
|
# The exif info needs to be written as one block, + APP1, + one spare byte.
|
|
# Ensure that our buffer is big enough
|
|
bufsize = max(ImageFile.MAXBLOCK, bufsize, len(info.get("exif", b"")) + 5)
|
|
|
|
ImageFile._save(im, fp, [("jpeg", (0, 0)+im.size, 0, rawmode)], bufsize)
|
|
|
|
|
|
def _save_cjpeg(im, fp, filename):
|
|
# ALTERNATIVE: handle JPEGs via the IJG command line utilities.
|
|
import os
|
|
import subprocess
|
|
tempfile = im._dump()
|
|
subprocess.check_call(["cjpeg", "-outfile", filename, tempfile])
|
|
try:
|
|
os.unlink(file)
|
|
except:
|
|
pass
|
|
|
|
|
|
##
|
|
# Factory for making JPEG and MPO instances
|
|
def jpeg_factory(fp=None, filename=None):
|
|
im = JpegImageFile(fp, filename)
|
|
mpheader = im._getmp()
|
|
try:
|
|
if mpheader[45057] > 1:
|
|
# It's actually an MPO
|
|
from .MpoImagePlugin import MpoImageFile
|
|
im = MpoImageFile(fp, filename)
|
|
except (TypeError, IndexError):
|
|
# It is really a JPEG
|
|
pass
|
|
return im
|
|
|
|
|
|
# -------------------------------------------------------------------q-
|
|
# Registry stuff
|
|
|
|
Image.register_open("JPEG", jpeg_factory, _accept)
|
|
Image.register_save("JPEG", _save)
|
|
|
|
Image.register_extension("JPEG", ".jfif")
|
|
Image.register_extension("JPEG", ".jpe")
|
|
Image.register_extension("JPEG", ".jpg")
|
|
Image.register_extension("JPEG", ".jpeg")
|
|
|
|
Image.register_mime("JPEG", "image/jpeg")
|