[ocrfeeder/introspection] Fix using newer versions of Unpaper

[Joaquim Manuel Pereira Rocha <jrocha src gnome org>]

commit 51972aa019d25eaaacb598f654a7e481b7196b06
Author: Joaquim Rocha <me joaquimrocha com>
Date:   Mon Jul 7 22:16:24 2014 +0200

    Fix using newer versions of Unpaper
    
    Unpaper has been forked and newer versions do not seem to work when
    the output image's name is the same one as the input's so the command
    had to be updated.
    
    gb#705610

 src/ocrfeeder/util/lib.py |   14 +++++++++-----
 1 files changed, 9 insertions(+), 5 deletions(-)
---
diff --git a/src/ocrfeeder/util/lib.py b/src/ocrfeeder/util/lib.py
index 5fff20a..1e7914e 100644
--- a/src/ocrfeeder/util/lib.py
+++ b/src/ocrfeeder/util/lib.py
@@ -135,19 +135,23 @@ def getUnpaperCommand(configuration_manager):
 def unpaperImage(configuration_manager, image_path):
     tmp_dir = configuration_manager.TEMPORARY_FOLDER
     prefix = os.path.splitext(image_path)[0]
-    unpapered_name = os.path.join(tmp_dir, os.path.basename(prefix) + '.ppm')
-    if os.path.exists(unpapered_name):
-        unpapered_name = getNonExistingFileName(unpapered_name)
+    basename = os.path.basename(prefix)
+    unpapered_in = getNonExistingFileName(os.path.join(tmp_dir,
+                                                       basename + '_orig.pnm'))
+    unpapered_name = getNonExistingFileName(os.path.join(tmp_dir,
+                                                         basename + '.pnm'))
     image_path = Image.open(image_path)
-    image_path.save(unpapered_name, format = 'PPM')
+    image_path.save(unpapered_in, format = 'PPM')
     command = getUnpaperCommand(configuration_manager)
-    command += ' %s %s' % (unpapered_name, unpapered_name)
+    command += ' %s %s' % (unpapered_in, unpapered_name)
     print command
     try:
         os.system(command)
     except Exception, exception:
         debug(exception)
         return None
+    finally:
+        os.unlink(unpapered_in)
     return unpapered_name
 
 def obtainScanners():