use LC_NUMERIC=C in imagemagick conversion.

because inkscape DPI handling differs by its value.

product/ERP5/Document/Image.py

@@ -30,6 +30,7 @@
 #
 ##############################################################################
 
+import os
 import string
 import struct
 import subprocess
@@ -342,7 +343,10 @@ class Image(TextConvertableMixin, File, OFSImage):
     if self.getContentType() == "image/svg+xml":
       data = transformUrlToDataURI(data)
 
+    env = os.environ.copy()
+    env.update({'LC_NUMERIC':'C'})
     process = subprocess.Popen(parameter_list,
+                               env=env,
                                stdin=subprocess.PIPE,
                                stdout=subprocess.PIPE,
                                stderr=subprocess.PIPE,

product/PortalTransforms/libtransforms/imagemagick_transform.py

 from Products.PortalTransforms.interfaces import ITransform
+import os
 import subprocess
 from zope.interface import implements
 
@@ -26,7 +27,10 @@ class ImageMagickTransforms:
         if depth:
             parameter_list.extend(['-depth', '%s' % depth, '-type', 'Palette'])
         parameter_list.append('%s:-' % self.format)
+        env = os.environ.copy()
+        env.update({'LC_NUMERIC':'C'})
         p = subprocess.Popen(parameter_list,
+                             env=env,
                              stdin=subprocess.PIPE,
                              stdout=subprocess.PIPE,
                              stderr=subprocess.PIPE,