mediagoblin/media_types/image/processing.py

   1 # GNU MediaGoblin -- federated, autonomous media hosting
   2 # Copyright (C) 2011, 2012 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 try:
  18     from PIL import Image
  19 except ImportError:
  20     import Image
  21 import os
  22 import logging
  23 import argparse
  24
  25 from mediagoblin import mg_globals as mgg
  26 from mediagoblin.db.models import MediaEntry
  27 from mediagoblin.processing import (
  28     BadMediaFail, FilenameBuilder,
  29     MediaProcessor, ProcessingManager)
  30 from mediagoblin.submit.lib import run_process_media
  31 from mediagoblin.tools.exif import exif_fix_image_orientation, \
  32     extract_exif, clean_exif, get_gps_data, get_useful, \
  33     exif_image_needs_rotation
  34 from mediagoblin.tools.translate import lazy_pass_to_ugettext as _
  35
  36 _log = logging.getLogger(__name__)
  37
  38 PIL_FILTERS = {
  39     'NEAREST': Image.NEAREST,
  40     'BILINEAR': Image.BILINEAR,
  41     'BICUBIC': Image.BICUBIC,
  42     'ANTIALIAS': Image.ANTIALIAS}
  43
  44 MEDIA_TYPE = 'mediagoblin.media_types.image'
  45
  46
  47 def resize_image(proc_state, resized, keyname, target_name, new_size,
  48                  exif_tags, workdir):
  49     """
  50     Store a resized version of an image and return its pathname.
  51
  52     Arguments:
  53     proc_state -- the processing state for the image to resize
  54     resized -- an image from Image.open() of the original image being resized
  55     keyname -- Under what key to save in the db.
  56     target_name -- public file path for the new resized image
  57     exif_tags -- EXIF data for the original image
  58     workdir -- directory path for storing converted image files
  59     new_size -- 2-tuple size for the resized image
  60     """
  61     config = mgg.global_config['media_type:mediagoblin.media_types.image']
  62
  63     resized = exif_fix_image_orientation(resized, exif_tags)  # Fix orientation
  64
  65     filter_config = config['resize_filter']
  66     try:
  67         resize_filter = PIL_FILTERS[filter_config.upper()]
  68     except KeyError:
  69         raise Exception('Filter "{0}" not found, choose one of {1}'.format(
  70             unicode(filter_config),
  71             u', '.join(PIL_FILTERS.keys())))
  72
  73     resized.thumbnail(new_size, resize_filter)
  74
  75     # Copy the new file to the conversion subdir, then remotely.
  76     tmp_resized_filename = os.path.join(workdir, target_name)
  77     with file(tmp_resized_filename, 'w') as resized_file:
  78         resized.save(resized_file, quality=config['quality'])
  79     proc_state.store_public(keyname, tmp_resized_filename, target_name)
  80
  81
  82 def resize_tool(proc_state, force, keyname, target_name,
  83                 conversions_subdir, exif_tags, new_size=None):
  84     # filename -- the filename of the original image being resized
  85     filename = proc_state.get_orig_filename()
  86
  87     # Use the default size if new_size was not given
  88     if not new_size:
  89         max_width = mgg.global_config['media:' + keyname]['max_width']
  90         max_height = mgg.global_config['media:' + keyname]['max_height']
  91         new_size = (max_width, max_height)
  92
  93     # If the size of the original file exceeds the specified size for the desized
  94     # file, a target_name file is created and later associated with the media
  95     # entry.
  96     # Also created if the file needs rotation, or if forced.
  97     try:
  98         im = Image.open(filename)
  99     except IOError:
 100         raise BadMediaFail()
 101     if force \
 102         or im.size[0] > new_size[0]\
 103         or im.size[1] > new_size[1]\
 104         or exif_image_needs_rotation(exif_tags):
 105         resize_image(
 106             proc_state, im, unicode(keyname), target_name,
 107             new_size,
 108             exif_tags, conversions_subdir)
 109
 110
 111 SUPPORTED_FILETYPES = ['png', 'gif', 'jpg', 'jpeg', 'tiff']
 112
 113
 114 def sniff_handler(media_file, **kw):
 115     _log.info('Sniffing {0}'.format(MEDIA_TYPE))
 116     if kw.get('media') is not None:  # That's a double negative!
 117         name, ext = os.path.splitext(kw['media'].filename)
 118         clean_ext = ext[1:].lower()  # Strip the . from ext and make lowercase
 119
 120         if clean_ext in SUPPORTED_FILETYPES:
 121             _log.info('Found file extension in supported filetypes')
 122             return MEDIA_TYPE
 123         else:
 124             _log.debug('Media present, extension not found in {0}'.format(
 125                     SUPPORTED_FILETYPES))
 126     else:
 127         _log.warning('Need additional information (keyword argument \'media\')'
 128                      ' to be able to handle sniffing')
 129
 130     return None
 131
 132
 133 class ProcessImage(object):
 134     """Code to process an image. Will be run by celery.
 135
 136     A Workbench() represents a local tempory dir. It is automatically
 137     cleaned up when this function exits.
 138     """
 139     def __init__(self, proc_state=None):
 140         if proc_state:
 141             self.proc_state = proc_state
 142             self.entry = proc_state.entry
 143             self.workbench = proc_state.workbench
 144
 145             # Conversions subdirectory to avoid collisions
 146             self.conversions_subdir = os.path.join(
 147                 self.workbench.dir, 'convirsions')
 148
 149             self.orig_filename = proc_state.get_orig_filename()
 150             self.name_builder = FilenameBuilder(self.orig_filename)
 151
 152             # Exif extraction
 153             self.exif_tags = extract_exif(self.orig_filename)
 154
 155             os.mkdir(self.conversions_subdir)
 156
 157     def reprocess_action(self, args):
 158         """
 159         List the available actions for media in a given state
 160         """
 161         if args[0].state == 'processed':
 162             print _('\n Available reprocessing actions for processed images:'
 163                     '\n \t --resize: thumb or medium'
 164                     '\n Options:'
 165                     '\n \t --size: max_width max_height (defaults to'
 166                     'config specs)')
 167             return True
 168
 169     def _parser(self, args):
 170         """
 171         Parses the unknown args from the gmg parser
 172         """
 173         parser = argparse.ArgumentParser()
 174         parser.add_argument(
 175             '--resize',
 176             choices=['thumb', 'medium'])
 177         parser.add_argument(
 178             '--size',
 179             nargs=2,
 180             metavar=('max_width', 'max_height'),
 181             type=int)
 182         parser.add_argument(
 183             '--initial_processing',
 184             action='store_true')
 185
 186         return parser.parse_args(args[1])
 187
 188     def _check_eligible(self, entry_args, reprocess_args):
 189         """
 190         Check to see if we can actually process the given media as requested
 191         """
 192
 193         if entry_args.state == 'processed':
 194             if reprocess_args.initial_processing:
 195                 raise Exception(_('You can not run --initial_processing on'
 196                                   ' media that has already been processed.'))
 197
 198         if entry_args.state == 'failed':
 199             if reprocess_args.resize:
 200                 raise Exception(_('You can not run --resize on media that has'
 201                                   ' not been processed.'))
 202             if reprocess_args.size:
 203                 _log.warn('With --initial_processing, the --size flag will be'
 204                           ' ignored.')
 205
 206         if entry_args.state == 'processing':
 207             raise Exception(_('We currently do not support reprocessing on'
 208                               ' media that is in the "processing" state.'))
 209
 210     def initial_processing(self):
 211         # Is there any GPS data
 212         gps_data = get_gps_data(self.exif_tags)
 213
 214          # Always create a small thumbnail
 215         resize_tool(self.proc_state, True, 'thumb', self.orig_filename,
 216                     self.name_builder.fill('{basename}.thumbnail{ext}'),
 217                     self.conversions_subdir, self.exif_tags)
 218
 219         # Possibly create a medium
 220         resize_tool(self.proc_state, False, 'medium', self.orig_filename,
 221                     self.name_builder.fill('{basename}.medium{ext}'),
 222                     self.conversions_subdir, self.exif_tags)
 223
 224         # Copy our queued local workbench to its final destination
 225         self.proc_state.copy_original(self.name_builder.fill('{basename}{ext}'))
 226
 227         # Remove queued media file from storage and database
 228         self.proc_state.delete_queue_file()
 229
 230         # Insert exif data into database
 231         exif_all = clean_exif(self.exif_tags)
 232
 233         if len(exif_all):
 234             self.entry.media_data_init(exif_all=exif_all)
 235
 236         if len(gps_data):
 237             for key in list(gps_data.keys()):
 238                 gps_data['gps_' + key] = gps_data.pop(key)
 239             self.entry.media_data_init(**gps_data)
 240
 241     def reprocess(self, reprocess_info):
 242         """
 243         This function actually does the reprocessing when called by
 244         ProcessMedia in gmg/processing/task.py
 245         """
 246         new_size = None
 247
 248         # Did they specify a size? They must specify either both or none, so
 249         # we only need to check if one is present
 250         if reprocess_info.get('max_width'):
 251             max_width = reprocess_info['max_width']
 252             max_height = reprocess_info['max_height']
 253
 254             new_size = (max_width, max_height)
 255
 256         resize_tool(self.proc_state, False, reprocess_info['resize'],
 257                     self.name_builder.fill('{basename}.medium{ext}'),
 258                     self.conversions_subdir, self.exif_tags, new_size)
 259
 260     def media_reprocess(self, args):
 261         """
 262         This function handles the all of the reprocessing logic, before calling
 263         gmg/submit/lib/run_process_media
 264         """
 265         reprocess_args = self._parser(args)
 266         entry_args = args[0]
 267
 268         # Can we actually process the given media as requested?
 269         self._check_eligible(entry_args, reprocess_args)
 270
 271         # Do we want to re-try initial processing?
 272         if reprocess_args.initial_processing:
 273             for id in entry_args.media_id:
 274                 entry = MediaEntry.query.filter_by(id=id).first()
 275                 run_process_media(entry)
 276
 277         # Are we wanting to resize the thumbnail or medium?
 278         elif reprocess_args.resize:
 279
 280             # reprocess all given media entries
 281             for id in entry_args.media_id:
 282                 entry = MediaEntry.query.filter_by(id=id).first()
 283
 284                 # For now we can only reprocess with the original file
 285                 if not entry.media_files.get('original'):
 286                     raise Exception(_('The original file for this media entry'
 287                                       ' does not exist.'))
 288
 289                 reprocess_info = self._get_reprocess_info(reprocess_args)
 290                 run_process_media(entry, reprocess_info=reprocess_info)
 291
 292         # If we are here, they forgot to tell us how to reprocess
 293         else:
 294             _log.warn('You must set either --resize or --initial_processing'
 295                       ' flag to reprocess an image.')
 296
 297     def _get_reprocess_info(self, args):
 298         """ Returns a dict with the info needed for reprocessing"""
 299         reprocess_info = {'resize': args.resize}
 300
 301         if args.size:
 302             reprocess_info['max_width'] = args.size[0]
 303             reprocess_info['max_height'] = args.size[1]
 304
 305         return reprocess_info
 306
 307
 308 class CommonImageProcessor(MediaProcessor):
 309     """
 310     Provides a base for various media processing steps
 311     """
 312     # Common resizing step
 313     def resize_step(self):
 314         pass
 315
 316     def _add_width_height_args(self, parser):
 317         parser.add_argument(
 318             "--width", default=None,
 319             help=(
 320                 "Width of the resized image (if not using defaults)"))
 321         parser.add_argument(
 322             "--height", default=None,
 323             help=(
 324                 "Height of the resized image (if not using defaults)"))
 325
 326
 327 class InitialProcessor(CommonImageProcessor):
 328     """
 329     Initial processing step for new images
 330     """
 331     name = "initial"
 332     description = "Initial processing"
 333
 334     @classmethod
 335     def media_is_eligibile(self, media_entry):
 336         """
 337         Determine if this media type is eligible for processing
 338         """
 339         return media_entry.state in (
 340             "unprocessed", "failed")
 341
 342     ###############################
 343     # Command line interface things
 344     ###############################
 345
 346     @classmethod
 347     def generate_parser(self):
 348         parser = argparse.ArgumentParser(
 349             description=self.description)
 350
 351         self._add_width_height_args(parser)
 352
 353         return parser
 354
 355     @classmethod
 356     def args_to_request(self, args):
 357         raise NotImplementedError
 358
 359
 360
 361 class ImageProcessingManager(ProcessingManager):
 362     def __init__(self):
 363         super(self.__class__, self).__init__()
 364         self.add_processor(InitialProcessor)
 365
 366
 367 if __name__ == '__main__':
 368     import sys
 369     import pprint
 370
 371     pp = pprint.PrettyPrinter()
 372
 373     result = extract_exif(sys.argv[1])
 374     gps = get_gps_data(result)
 375     clean = clean_exif(result)
 376     useful = get_useful(clean)
 377
 378     print pp.pprint(
 379         clean)