mediagoblin/media_types/video/processing.py

   1 # GNU MediaGoblin -- federated, autonomous media hosting
   2 # Copyright (C) 2011 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 tempfile
  18 import logging
  19 import os
  20
  21 from mediagoblin import mg_globals as mgg
  22 from mediagoblin.processing import mark_entry_failed, \
  23     THUMB_SIZE, MEDIUM_SIZE, create_pub_filepath
  24 from . import transcoders
  25
  26 logging.basicConfig()
  27
  28 _log = logging.getLogger(__name__)
  29 _log.setLevel(logging.DEBUG)
  30
  31
  32 def process_video(entry):
  33     """
  34     Code to process a video
  35
  36     Much of this code is derived from the arista-transcoder script in
  37     the arista PyPI package and changed to match the needs of
  38     MediaGoblin
  39
  40     This function sets up the arista video encoder in some kind of new thread
  41     and attaches callbacks to that child process, hopefully, the
  42     entry-complete callback will be called when the video is done.
  43     """
  44     workbench = mgg.workbench_manager.create_workbench()
  45
  46     queued_filepath = entry['queued_media_file']
  47     queued_filename = workbench.localized_file(
  48         mgg.queue_store, queued_filepath,
  49         'source')
  50
  51     medium_filepath = create_pub_filepath(
  52         entry,
  53         '{original}-640p.webm'.format(
  54             original=os.path.splitext(
  55                 queued_filepath[-1])[0]  # Select the
  56             ))
  57
  58     thumbnail_filepath = create_pub_filepath(
  59         entry, 'thumbnail.jpg')
  60
  61
  62     # Create a temporary file for the video destination
  63     tmp_dst = tempfile.NamedTemporaryFile()
  64
  65     with tmp_dst:
  66         # Transcode queued file to a VP8/vorbis file that fits in a 640x640 square
  67         transcoder = transcoders.VideoTranscoder(queued_filename, tmp_dst.name)
  68
  69         # Push transcoded video to public storage
  70         _log.debug('Saving medium...')
  71         mgg.public_store.get_file(medium_filepath, 'wb').write(
  72             tmp_dst.read())
  73         _log.debug('Saved medium')
  74
  75         entry['media_files']['webm_640'] = medium_filepath
  76
  77         # Save the width and height of the transcoded video
  78         entry['media_data']['video'] = {
  79             u'width': transcoder.dst_data.videowidth,
  80             u'height': transcoder.dst_data.videoheight}
  81
  82     # Create a temporary file for the video thumbnail
  83     tmp_thumb = tempfile.NamedTemporaryFile()
  84
  85     with tmp_thumb:
  86         # Create a thumbnail.jpg that fits in a 180x180 square
  87         transcoders.VideoThumbnailer(queued_filename, tmp_thumb.name)
  88
  89         # Push the thumbnail to public storage
  90         _log.debug('Saving thumbnail...')
  91         mgg.public_store.get_file(thumbnail_filepath, 'wb').write(
  92             tmp_thumb.read())
  93         _log.debug('Saved thumbnail')
  94
  95         entry['media_files']['thumb'] = thumbnail_filepath
  96
  97
  98     # Push original file to public storage
  99     queued_file = file(queued_filename, 'rb')
 100
 101     with queued_file:
 102         original_filepath = create_pub_filepath(
 103             entry,
 104             queued_filepath[-1])
 105
 106         with mgg.public_store.get_file(original_filepath, 'wb') as \
 107                 original_file:
 108             _log.debug('Saving original...')
 109             original_file.write(queued_file.read())
 110             _log.debug('Saved original')
 111
 112             entry['media_files']['original'] = original_filepath
 113
 114     mgg.queue_store.delete_file(queued_filepath)
 115
 116
 117     # Save the MediaEntry
 118     entry.save()