def select_features(cls, features_id, file_struct, annot_beats, framesync):
"""Selects the features from the given parameters.
Parameters
----------
features_id: str
The identifier of the features (it must be a key inside the
`features_registry`)
file_struct: msaf.io.FileStruct
The file struct containing the files to extract the features from
annot_beats: boolean
Whether to use annotated (`True`) or estimated (`False`) beats
framesync: boolean
Whether to use framesync (`True`) or beatsync (`False`) features
Returns
-------
features: obj
The actual features object that inherits from `msaf.Features`
"""
if not annot_beats and framesync:
feat_type = FeatureTypes.framesync
elif annot_beats and not framesync:
feat_type = FeatureTypes.ann_beatsync
elif not annot_beats and not framesync:
feat_type = FeatureTypes.est_beatsync
else:
raise FeatureTypeNotFound("Type of features not valid.")
# Select features with default parameters
if features_id not in features_registry.keys():
raise FeaturesNotFound(
"The features '%s' are invalid (valid features are %s)" %
(features_id, features_registry.keys()))
return features_registry[features_id](file_struct, feat_type)
def read_features(self, tol=1e-3):
"""Reads the features from a file and stores them in the current
object.
Parameters
----------
tol: float
Tolerance level to detect duration of audio.
"""
try:
# Read JSON file
with open(self.file_struct.features_file) as f:
feats = json.load(f)
# Store duration
if self.dur is None:
self.dur = float(feats["globals"]["dur"])
# Check that we have the correct global parameters
assert (np.isclose(self.dur,
float(feats["globals"]["dur"]),
rtol=tol))
assert (self.sr == int(feats["globals"]["sample_rate"]))
assert (self.hop_length == int(feats["globals"]["hop_length"]))
assert (os.path.basename(
self.file_struct.audio_file) == os.path.basename(
feats["globals"]["audio_file"]))
# Check for specific features params
feat_params_err = FeatureParamsError(
"Couldn't find features for %s id in file %s" %
(self.get_id(), self.file_struct.features_file))
if self.get_id() not in feats.keys():
raise feat_params_err
for param_name in self.get_param_names():
value = getattr(self, param_name)
if hasattr(value, '__call__'):
# Special case of functions
if value.__name__ != \
feats[self.get_id()]["params"][param_name]:
raise feat_params_err
else:
if str(value) != \
feats[self.get_id()]["params"][param_name]:
raise feat_params_err
# Store actual features
self._est_beats_times = np.array(feats["est_beats"])
self._est_beatsync_times = np.array(feats["est_beatsync_times"])
self._est_beats_frames = librosa.core.time_to_frames(
self._est_beats_times, sr=self.sr, hop_length=self.hop_length)
self._framesync_features = \
np.array(feats[self.get_id()]["framesync"])
self._est_beatsync_features = \
np.array(feats[self.get_id()]["est_beatsync"])
# Read annotated beats if available
if "ann_beats" in feats.keys():
self._ann_beats_times = np.array(feats["ann_beats"])
self._ann_beatsync_times = np.array(
feats["ann_beatsync_times"])
self._ann_beats_frames = librosa.core.time_to_frames(
self._ann_beats_times,
sr=self.sr,
hop_length=self.hop_length)
self._ann_beatsync_features = \
np.array(feats[self.get_id()]["ann_beatsync"])
except KeyError:
raise WrongFeaturesFormatError(
"The features file %s is not correctly formatted" %
self.file_struct.features_file)
except AssertionError:
raise FeaturesNotFound(
"The features for the given parameters were not found in "
"features file %s" % self.file_struct.features_file)
except IOError:
raise NoFeaturesFileError("Could not find features file %s",
self.file_struct.features_file)