QGIS » QGIS Application

OS: Windows 7 Enterprise SP1 64bit
QGIS: default installation http://qgis.org/downloads/QGIS-OSGeo4W-2.2.0-1-Setup-x86_64.exe

I'm writing a plugin to handle images using PIL, used the code below in the Python Console, which raises error "decoder jpeg not available". This also happens on another machine with http://download.osgeo.org/osgeo4w/osgeo4w-setup-x86_64.exe installed. How can i get PIL to work with JPEG, PNG, PDF and other formats/encoders?

import Image
image = Image.open("R:\\ScannedDocuments\\testimage.jpg")
image.save("R:\\ScannedDocuments\\testimage.tiff", "TIFF")

The following messages are produced, in essence complaining about a jpeg decoder not being available.

Traceback (most recent call last):
File "<input>", line 1, in <module>
File "J:/ScannedDocuments/ImageHandling.py", line 3, in <module>
image.save("R:\\ScannedDocuments\\testimage.tiff", "TIFF")
File "C:\\PROGRA~1\\QGISVA~1\\apps\\Python27\\lib\\site-packages\\PIL\\Image.py", line 1406, in save
self.load()
File "C:\\PROGRA~1\\QGISVA~1\\apps\\Python27\\lib\\site-packages\\PIL\\ImageFile.py", line 189, in load
d = Image._getdecoder(self.mode, d, a, self.decoderconfig)
File "C:\\PROGRA~1\\QGISVA~1\\apps\\Python27\\lib\\site-packages\\PIL\\Image.py", line 385, in _getdecoder
raise IOError("decoder %s not available" % decoder_name)
IOError: decoder jpeg not available