mediagoblin/media_types/raw_image/processing.py

   1 # GNU MediaGoblin -- federated, autonomous media hosting
   2 # Copyright (C) 2014 MediaGoblin contributors.  See AUTHORS.
   3 #
   4 # This program is free software: you can redistribute it and/or modify
   5 # it under the terms of the GNU Affero General Public License as published by
   6 # the Free Software Foundation, either version 3 of the License, or
   7 # (at your option) any later version.
   8 #
   9 # This program is distributed in the hope that it will be useful,
  10 # but WITHOUT ANY WARRANTY; without even the implied warranty of
  11 # MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  12 # GNU Affero General Public License for more details.
  13 #
  14 # You should have received a copy of the GNU Affero General Public License
  15 # along with this program.  If not, see <http://www.gnu.org/licenses/>.
  16
  17 import os
  18 import logging
  19
  20 # This needs to handle the case where it's missing
  21 import pyexiv2
  22
  23 from mediagoblin.media_types.image.processing import (
  24     InitialProcessor, Resizer)
  25 from mediagoblin.processing import (
  26     FilenameBuilder, ProcessingManager)
  27
  28
  29 _log = logging.getLogger(__name__)
  30
  31 MEDIA_TYPE = 'mediagoblin.media_types.raw_image'
  32 ACCEPTED_EXTENSIONS = ['nef', 'cr2']
  33
  34
  35 # The entire function have to be copied
  36
  37 def sniff_handler(media_file, filename):
  38     _log.info('Sniffing {0}'.format(MEDIA_TYPE))
  39     name, ext = os.path.splitext(filename)
  40     clean_ext = ext[1:].lower()  # Strip the . from ext and make lowercase
  41
  42     if clean_ext in ACCEPTED_EXTENSIONS:
  43         _log.info('Found file extension in supported filetypes')
  44         return MEDIA_TYPE
  45     else:
  46         _log.debug('Media present, extension not found in {0}'.format(
  47                 ACCEPTED_EXTENSIONS))
  48
  49     return None
  50
  51
  52 class InitialRawProcessor(InitialProcessor):
  53     def common_setup(self):
  54         """
  55         Pull out a full-size JPEG-preview
  56         """
  57         super(InitialRawProcessor, self).common_setup()
  58
  59         self._original_raw = self.process_filename
  60
  61         # Read EXIF data
  62         md = pyexiv2.ImageMetadata(self._original_raw)
  63         md.read()
  64         self.process_filename = os.path.join(self.conversions_subdir,
  65             self.entry.queued_media_file[-1])
  66
  67         # Extract the biggest preview and write it as our working image
  68         md.previews[-1].write_to_file(
  69             self.process_filename.encode('utf-8'))
  70         self.process_filename += '.jpg'
  71         _log.debug(u'Wrote new file from {0} to preview (jpg) {1}'.format(
  72             self._original_raw, self.process_filename))
  73
  74         # Override the namebuilder with our new jpg-based name
  75         self.name_builder = FilenameBuilder(self.process_filename)
  76
  77
  78 class RawImageProcessingManager(ProcessingManager):
  79     def __init__(self):
  80         super(RawImageProcessingManager, self).__init__()
  81         self.add_processor(InitialRawProcessor)
  82         self.add_processor(Resizer)
  83
  84     def workflow(self, entry, manager, feed_url, reprocess_action,
  85                  reprocess_info=None):
  86         ProcessMedia().apply_async(
  87             [entry.id, feed_url, reprocess_action, reprocess_info], {},
  88             task_id=entry.queued_task_id)