sintonia/python_apps/media-monitor2/media/monitor/metadata.py

173 lines
6.7 KiB
Python

# -*- coding: utf-8 -*-
import mutagen
import math
import os
import copy
from media.monitor.exceptions import BadSongFile
from media.monitor.log import Loggable
import media.monitor.pure as mmp
"""
list of supported easy tags in mutagen version 1.20
['albumartistsort', 'musicbrainz_albumstatus', 'lyricist', 'releasecountry',
'date', 'performer', 'musicbrainz_albumartistid', 'composer', 'encodedby',
'tracknumber', 'musicbrainz_albumid', 'album', 'asin', 'musicbrainz_artistid',
'mood', 'copyright', 'author', 'media', 'length', 'version', 'artistsort',
'titlesort', 'discsubtitle', 'website', 'musicip_fingerprint', 'conductor',
'compilation', 'barcode', 'performer:*', 'composersort', 'musicbrainz_discid',
'musicbrainz_albumtype', 'genre', 'isrc', 'discnumber', 'musicbrainz_trmid',
'replaygain_*_gain', 'musicip_puid', 'artist', 'title', 'bpm',
'musicbrainz_trackid', 'arranger', 'albumsort', 'replaygain_*_peak',
'organization']
"""
airtime2mutagen = {
"MDATA_KEY_TITLE": "title",
"MDATA_KEY_CREATOR": "artist",
"MDATA_KEY_SOURCE": "album",
"MDATA_KEY_GENRE": "genre",
"MDATA_KEY_MOOD": "mood",
"MDATA_KEY_TRACKNUMBER": "tracknumber",
"MDATA_KEY_BPM": "bpm",
"MDATA_KEY_LABEL": "organization",
"MDATA_KEY_COMPOSER": "composer",
"MDATA_KEY_ENCODER": "encodedby",
"MDATA_KEY_CONDUCTOR": "conductor",
"MDATA_KEY_YEAR": "date",
"MDATA_KEY_URL": "website",
"MDATA_KEY_ISRC": "isrc",
"MDATA_KEY_COPYRIGHT": "copyright",
}
# Some airtime attributes are special because they must use the mutagen object
# itself to calculate the value that they need. The lambda associated with each
# key should attempt to extract the corresponding value from the mutagen object
# itself pass as 'm'. In the case when nothing can be extracted the lambda
# should return some default value to be assigned anyway or None so that the
# airtime metadata object will skip the attribute outright.
airtime_special = {
"MDATA_KEY_DURATION" :
lambda m: format_length(getattr(m.info, u'length', 0.0)),
"MDATA_KEY_BITRATE" :
lambda m: getattr(m.info, "bitrate", 0),
"MDATA_KEY_SAMPLERATE" :
lambda m: getattr(m.info, u'sample_rate', 0),
"MDATA_KEY_MIME" :
lambda m: m.mime[0] if len(m.mime) > 0 else u'',
}
mutagen2airtime = dict( (v,k) for k,v in airtime2mutagen.iteritems() if isinstance(v, str) )
truncate_table = {
'MDATA_KEY_GENRE' : 64,
'MDATA_KEY_TITLE' : 512,
'MDATA_KEY_CREATOR' : 512,
'MDATA_KEY_SOURCE' : 512,
'MDATA_KEY_MOOD' : 64,
'MDATA_KEY_LABEL' : 512,
'MDATA_KEY_COMPOSER' : 512,
'MDATA_KEY_ENCODER' : 255,
'MDATA_KEY_CONDUCTOR' : 512,
'MDATA_KEY_YEAR' : 16,
'MDATA_KEY_URL' : 512,
'MDATA_KEY_ISRC' : 512,
'MDATA_KEY_COPYRIGHT' : 512,
}
def format_length(mutagen_length):
"""Convert mutagen length to airtime length"""
t = float(mutagen_length)
h = int(math.floor(t / 3600))
t = t % 3600
m = int(math.floor(t / 60))
s = t % 60
# will be ss.uuu
s = str(s)
seconds = s.split(".")
s = seconds[0]
# have a maximum of 6 subseconds.
if len(seconds[1]) >= 6: ss = seconds[1][0:6]
else: ss = seconds[1][0:]
return "%s:%s:%s.%s" % (h, m, s, ss)
def truncate_to_length(item, length):
if isinstance(item, int): item = str(item)
if isinstance(item, basestring):
if len(item) > length: return item[0:length]
else: return item
class Metadata(Loggable):
# TODO : refactor the way metadata is being handled. Right now things are a
# little bit messy. Some of the handling is in m.m.pure while the rest is
# here. Also interface is not very consistent
@staticmethod
def write_unsafe(path,md):
if not os.path.exists(path):
raise BadSongFile(path)
song_file = mutagen.File(path, easy=True)
for airtime_k, airtime_v in md.iteritems():
if airtime_k in airtime2mutagen:
# The unicode cast here is mostly for integers that need to be
# strings
song_file[ airtime2mutagen[airtime_k] ] = unicode(airtime_v)
song_file.save()
def __init__(self, fpath):
# Forcing the unicode through
try: fpath = fpath.decode("utf-8")
except: pass
try: full_mutagen = mutagen.File(fpath, easy=True)
except Exception: raise BadSongFile(fpath)
self.path = fpath
# TODO : Simplify the way all of these rules are handled right not it's
# extremely unclear and needs to be refactored.
metadata = {}
# Load only the metadata avilable in mutagen into metdata
for k,v in full_mutagen.iteritems():
# Special handling of attributes here
if isinstance(v, list):
# TODO : some files have multiple fields for the same metadata.
# genre is one example. In that case mutagen will return a list
# of values
metadata[k] = v[0]
#if len(v) == 1: metadata[k] = v[0]
#else: raise Exception("Unknown mutagen %s:%s" % (k,str(v)))
else: metadata[k] = v
self.__metadata = {}
# Start populating a dictionary of airtime metadata in __metadata
for muta_k, muta_v in metadata.iteritems():
# We must check if we can actually translate the mutagen key into
# an airtime key before doing the conversion
if muta_k in mutagen2airtime:
airtime_key = mutagen2airtime[muta_k]
# Apply truncation in the case where airtime_key is in our
# truncation table
muta_v = \
truncate_to_length(muta_v, truncate_table[airtime_key])\
if airtime_key in truncate_table else muta_v
self.__metadata[ airtime_key ] = muta_v
# Now we extra the special values that are calculated from the mutagen
# object itself:
for special_key,f in airtime_special.iteritems():
new_val = f(full_mutagen)
if new_val is not None:
self.__metadata[special_key] = f(full_mutagen)
# Finally, we "normalize" all the metadata here:
self.__metadata = mmp.normalized_metadata(self.__metadata, fpath)
# Now we must load the md5:
self.__metadata['MDATA_KEY_MD5'] = mmp.file_md5(fpath)
#self.__metadata['MDATA_KEY_REPLAYGAIN'] = \
#gain.calculate_replay_gain(fpath)
def is_recorded(self):
return mmp.is_airtime_recorded( self.__metadata )
def extract(self):
return copy.deepcopy(self.__metadata)
def utf8(self):
return mmp.convert_dict_value_to_utf8(self.extract())