'Add any images that were created after the call to add_resources()'

def add_extra_images(self):

    for item in self.oeb.manifest.values():
        if ((item.media_type not in OEB_RASTER_IMAGES) or (item.href in self.item_map)):
            continue
        try:
            data = self.process_image(item.data)
        except:
            self.log.warn((u'Bad    image    file    %r' % item.href))
        else:
            self.records.append(data)
            self.item_map[item.href] = len(self.records)
        finally:
            item.unload_data_from_memory()
