whipper-gui/whipper/common/encode.py

# -*- Mode: Python; test-case-name: whipper.test.test_common_encode -*-
# vi:si:et:sw=4:sts=4:ts=4

# Copyright (C) 2009 Thomas Vander Stichele

# This file is part of whipper.
#
# whipper is free software: you can redistribute it and/or modify
# it under the terms of the GNU General Public License as published by
# the Free Software Foundation, either version 3 of the License, or
# (at your option) any later version.
#
# whipper is distributed in the hope that it will be useful,
# but WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
# GNU General Public License for more details.
#
# You should have received a copy of the GNU General Public License
# along with whipper.  If not, see <http://www.gnu.org/licenses/>.


from mutagen.flac import FLAC, Picture
from mutagen.id3 import PictureType

from whipper.extern.task import task

from whipper.program import sox
from whipper.program import flac

import logging
logger = logging.getLogger(__name__)


class SoxPeakTask(task.Task):
    description = 'Calculating peak level'

    def __init__(self, track_path):
        self.track_path = track_path
        self.peak = None

    def start(self, runner):
        task.Task.start(self, runner)
        self.schedule(0.0, self._sox_peak)

    def _sox_peak(self):
        self.peak = sox.peak_level(self.track_path)
        self.stop()


class FlacEncodeTask(task.Task):
    description = 'Encoding to FLAC'

    def __init__(self, track_path, track_out_path, what="track"):
        self.track_path = track_path
        self.track_out_path = track_out_path
        self.new_path = None
        self.description = 'Encoding %s to FLAC' % what

    def start(self, runner):
        task.Task.start(self, runner)
        self.schedule(0.0, self._flac_encode)

    def _flac_encode(self):
        flac.encode(self.track_path, self.track_out_path)
        self.stop()


class TaggingTask(task.Task):
    # TODO: Wizzup: Do we really want this as 'Task'...?
    # I only made it a task for now because that it's easier to integrate in
    # program/cdparanoia.py - where whipper currently does the tagging.
    # We should just move the tagging to a more sensible place.

    description = 'Writing tags to FLAC'

    def __init__(self, track_path, tags):
        self.track_path = track_path
        self.tags = tags

    def start(self, runner):
        task.Task.start(self, runner)
        self.schedule(0.0, self._tag)

    def _tag(self):
        w = FLAC(self.track_path)

        for k, v in list(self.tags.items()):
            w[k] = v

        w.save()

        self.stop()


class EmbedPictureTask(task.Task):
    description = 'Embed picture to FLAC'

    def __init__(self, track_path, cover_art_path):
        self.track_path = track_path
        self.cover_art_path = cover_art_path

    def start(self, runner):
        task.Task.start(self, runner)
        self.schedule(0.0, self._embed_picture)

    def _make_flac_picture(self, cover_art_filename):
        """
        Given a path to a jpg/png file, return a FLAC picture for embedding.

        The embedding will be performed using the mutagen module.

        :param cover_art_filename: path to cover art image file
        :type cover_art_filename: str
        :returns: a valid FLAC picture for embedding
        :rtype: mutagen.flac.Picture or None
        """
        if not cover_art_filename:
            return

        from PIL import Image

        im = Image.open(cover_art_filename)
        # NOTE: the cover art thumbnails we're getting from the Cover Art
        # Archive should be always in the JPEG format: this check is currently
        # useless but will leave it here to better handle unexpected formats.
        if im.format == 'JPEG':
            mime = 'image/jpeg'
        elif im.format == 'PNG':
            mime = 'image/png'
        else:
            # we only support png and jpeg
            logger.warning("no cover art will be added because the fetched "
                           "image format is unsupported")
            return

        pic = Picture()
        with open(cover_art_filename, 'rb') as f:
            pic.data = f.read()

        pic.type = PictureType.COVER_FRONT
        pic.mime = mime
        pic.width, pic.height = im.size
        if im.mode not in ('P', 'RGB', 'SRGB'):
            logger.warning("no cover art will be added because the fetched "
                           "image mode is unsupported")
            return

        return pic

    def _embed_picture(self):
        """
        Get flac picture generated from mutagen.flac.Picture then embed
        it to given track if the flac picture exists.
        """
        flac_pic = self._make_flac_picture(self.cover_art_path)
        if flac_pic:
            w = FLAC(self.track_path)
            w.add_picture(flac_pic)

        self.stop()