X-Git-Url: https://scm.cri.minesparis.psl.eu/git/Photo.git/blobdiff_plain/b0a7e10b4f32cf74864bb53268ca4d3080f23bc0..6c41809185e322ce2d30e98234f71144f78f06c0:/Products/Photo/xmp.py

diff --git a/Products/Photo/xmp.py b/Products/Photo/xmp.py
new file mode 100755
index 0000000..8738e50
--- /dev/null
+++ b/Products/Photo/xmp.py
@@ -0,0 +1,189 @@
+# -*- coding: utf-8 -*-
+#######################################################################################
+#   Photo is a part of Plinn - http://plinn.org                                       #
+#   Copyright © 2008  Benoît PIN <benoit.pin@ensmp.fr>                                #
+#                                                                                     #
+#   This program is free software; you can redistribute it and/or                     #
+#   modify it under the terms of the GNU General Public License                       #
+#   as published by the Free Software Foundation; either version 2                    #
+#   of the License, or (at your option) any later version.                            #
+#                                                                                     #
+#   This program is distributed in the hope that it will be useful,                   #
+#   but WITHOUT ANY WARRANTY; without even the implied warranty of                    #
+#   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the                     #
+#   GNU General Public License for more details.                                      #
+#                                                                                     #
+#   You should have received a copy of the GNU General Public License                 #
+#   along with this program; if not, write to the Free Software                       #
+#   Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, USA.   #
+#######################################################################################
+# 
+# 
+
+from types import StringTypes
+from logging import getLogger
+import re
+console = getLogger('Photo.xmp')
+
+class XMP(object) :
+	XMP_HEADER = u'<?xpacket begin="\ufeff" id="W5M0MpCehiHzreSzNTczkc9d"?>'
+	XMP_HEADER_PATTERN = u'''<\?xpacket begin=['"]\ufeff['"] id=['"]W5M0MpCehiHzreSzNTczkc9d['"][^\?]*\?>'''
+	XMP_PADDING_LINE = u'\u0020' * 63 + u'\n'
+	XMP_TRAILER = u'<?xpacket end="w"?>'
+
+	_readers = {}
+	_writers = {}
+
+	
+	
+	def __init__(self, file, content_type='image/jpeg', encoding='utf-8') :
+		try :
+			self.reader = self._readers[content_type]
+		except KeyError:
+			raise NotImplementedError, "%r content type not supported by XMP" % content_type
+		
+		try :
+			self.writer = self._writers[content_type]
+		except KeyError :
+			self.writer = None
+			console.info('XMP file opened on read-only mode.')
+		
+		self.file = file
+		self.encoding = encoding
+		self.xmp = None
+		self._open()
+	
+
+	def __del__(self) :
+		try :
+			self.file.close()
+		except :
+			pass
+	
+
+	def _open(self) :
+
+		if type(self.file) in StringTypes :
+			self.file = file(self.file)
+
+		packet = self.reader(self.file)
+		
+		if packet is not None :
+			# tests / unwrap
+			reEncodedHeader = re.compile(self.XMP_HEADER_PATTERN.encode(self.encoding))
+			m = reEncodedHeader.match(packet)
+			if m is None :
+				console.warn('XMP packet wrapper not found')
+				self.xmp = packet
+				return
+
+			xmp = packet[m.end():]
+			trailer = self.XMP_TRAILER[:-6].encode(self.encoding)  # TODO handle read-only mode
+			trailerPos = xmp.find(trailer)
+			assert trailerPos != -1, "No xmp trailer found"
+		
+			xmp = xmp[:trailerPos]
+			xmp = xmp.strip()
+			self.xmp = xmp
+		else :
+			self.xmp = None
+	
+	def save(self, f=None):
+		original = self.file
+		if f :
+			if type(f) in StringTypes :
+				new = file(f, 'w')
+			else :
+				new = f
+		elif f is None :
+			new = self.file
+		
+		self.writer(original, new, self.xmp)
+				
+	
+	def getXMP(self) :
+		return self.xmp
+	
+	
+	def setXMP(self, xmp) :
+		self.xmp = xmp
+
+	#
+	# xmp utils
+	#
+	
+	@staticmethod
+	def getXmpPadding(size) :
+		# size of trailer in kB
+		return (XMP.XMP_PADDING_LINE * 32 * size)
+	
+	
+	@staticmethod
+	def genXMPPacket(uXmpData, paddingSize):
+		packet = u''
+
+		packet += XMP.XMP_HEADER
+		packet += uXmpData
+		packet += XMP.getXmpPadding(paddingSize)
+		packet += XMP.XMP_TRAILER
+
+		return packet
+	
+
+	
+	#
+	# content type registry stuff
+	#
+	
+		
+	@classmethod
+	def registerReader(cls, content_type, reader) :
+		cls._readers[content_type] = reader
+
+	@classmethod
+	def registerWriter(cls, content_type, writer) :
+		cls._writers[content_type] = writer
+	
+	@classmethod
+	def registerWrapper(cls, content_type, wrapper) :
+		""" Registers specific wrapper to prepare data
+			for embedding xmp into specific content_type file.
+		"""
+		pass
+
+
+
+def test() :
+	from xml.dom.minidom import parse
+	data = parse('new.xmp').documentElement.toxml()
+
+	def test1() :
+		original = 'original.jpg'
+		modified = 'modified.jpg'
+	
+		x = XMP(original)
+		x.setXMP(data)
+		x.save(modified)
+
+	def test2() :
+		from cStringIO import StringIO
+		sio = StringIO()
+		sio.write(file('modified.jpg').read())
+		sio.seek(0)
+
+		x = XMP(sio)
+		x.setXMP(data)
+		x.save()
+		
+		f2 = open('modified2.jpg', 'w')
+		f2.write(sio.read())
+		f2.close()
+	
+	
+	test1()
+	test2()
+		
+
+		
+if __name__ == '__main__' :
+	test()