doc: added FAQ

doc/FAQ.rst

@@ -0,0 +1,27 @@
+==========================
+Frequently Asked Questions
+==========================
+
+Can I extract all images from MS OLE2 documents with olefile?
+-------------------------------------------------------------
+
+Not directly: images are not always stored the same way, and it also depends on the format.
+
+For example in Powerpoint presentations, you may find a stream named "Pictures"
+when running "olefile yourfile.ppt". You may extract the stream by using the
+openstream() method on the OleFileIO object, but you will usually get a binary
+stream containing several picture files. You may also extract it manually using
+tools such as SSView (http://www.mitec.cz/ssv.html).
+
+Then the only way I've found so far is to use file carving tools which are
+able to determine the beginning and the end of each picture in a binary file.
+These tools are not always easy to use but if you're interested have a look
+at http://pypi.python.org/pypi/hachoir-subfile
+and http://www.forensicswiki.org/wiki/Tools:Data_Recovery#Carving.
+
+If you really need to automate the process then you have to study Microsoft
+specifications (at http://www.microsoft.com/interop/docs/officebinaryformats.mspx)
+and find the right way to parse MS Office documents...
+
+A lot of people (including me) would be very interested if you find a solution! ;-)
+

doc/index.rst

@@ -35,6 +35,7 @@ Microscopy file formats, McAfee antivirus quarantine files, etc.
     Howto
     OLE_Overview
     olefile
+    FAQ