Source code for compiam.rhythm.transcription.mnemonic_transcription

import csv
import pickle

import hmmlearn.hmm as hmm
import librosa
import numpy as np
from sklearn.exceptions import NotFittedError
import tqdm

from compiam.exceptions import ModelNotTrainedError
from compiam.rhythm.meter.akshara_pulse_tracker import AksharaPulseTracker
from compiam.utils import get_logger

logger = get_logger(__name__)


[docs] class MnemonicTranscription: """ bōl or solkattu transcription from audio. Based on model presented in [1] [1] Gupta, S., Srinivasamurthy, A., Kumar, M., Murthy, H., & Serra, X. (2015, October). Discovery of Syllabic Percussion Patterns in Tabla Solo Recordings. In Proceedings of the 16th International Society for Music Information Retrieval Conference (ISMIR 2015) (pp. 385--391). Malaga, Spain. """ def __init__( self, syllables, feature_kwargs={"n_mfcc": 13, "win_length": 1024, "hop_length": 256}, model_kwargs={ "n_components": 7, "n_mix": 3, "n_iter": 100, "algorithm": "viterbi", "params": "mcw", }, sr=44100, ): """ :param syllables: List of strings representing expected bōl/solkattu syllables OR dict of string:string mappings. If a dict is passed, any subsequent syllable labels passed at training time will be converted as per this mapping. The values of this dict will act as the bōl/solkattu "vocabulary" for this model. :type syllables: list or dict :param feature_kwargs: Dict of parameters to pass to librosa.feature.mfcc or librosa.feature.delta. Defaults are selected as per [1] :type feature_kwargs: dict :param model_kwargs: Dict of parameters to pass to hmmlearn.hmm.GMMHMM. Defaults are selected as per [1] :type model_kwargs: dict :param sr: sampling rate of audio to train on (default 44.1Hz) :type sr: int [1] Gupta, S., Srinivasamurthy, A., Kumar, M., Murthy, H., & Serra, X. (2015, October). Discovery of Syllabic Percussion Patterns in Tabla Solo Recordings. In Proceedings of the 16th International Society for Music Information Retrieval Conference (ISMIR 2015) (pp. 385-391). Malaga, Spain. """ self.sr = sr if isinstance(syllables, dict): self.syllables = set(syllables.values()) self.mapping = syllables else: self.syllables = set(syllables) self.mapping = {x: x for x in syllables} self.models = {} for s in self.syllables: self.models[s] = hmm.GMMHMM(**model_kwargs) self.feature_kwargs = feature_kwargs self.trained = False
[docs] def train(self, file_paths_audio, file_paths_annotation, sr=None): """ Train one gaussian mixture model hidden markov model for each syllables passed at initialisation on input audios and annotations passed via <file_paths_audio> and <file_paths_annotation>. Training hyperparameters are configured upon intialisation and can be accessed/changed via self.model_kwargs. :param file_paths_audio: List of file_paths to audios to train on :type file_paths_audio: list :param file_paths_annotation: List of file_paths to annotations to train on. annotations should be in csv format, with no header of (timestamp in seconds, <syllable>). Annotated syllables that do not correspond to syllables passed at initialisation will be ignored One annotations path should be passed for each audio path :type file_paths_annotation: list :param sr: sampling rate of audio to train on (default <self.sr>) :param sr: int """ if not len(file_paths_audio) == len(file_paths_annotation): raise Exception( "file_paths_audio and file_paths_annotation must be the same length" ) sr = self.sr if not sr else sr samples = {s: [] for s in self.syllables} # load and extract features for fau, fan in zip(file_paths_audio, file_paths_annotation): audio, _ = librosa.load(fau, sr=sr) annotations = self.load_annotations(fan) annotations = [(round(t * sr), self.map(a)) for t, a in annotations] ann_syls = set([x[1] for x in annotations]) # Extract melodic features features = self.extract_features(audio, sr=sr) for syl in ann_syls: if not syl in self.syllables: continue # get params hop_length = self.feature_kwargs["hop_length"] # get training samples relevant to syl samples_ix = self.get_sample_ix(annotations, audio, syl) samples_ix = [ (int(i / hop_length), int(j / hop_length)) for i, j in samples_ix ] samples[syl] = samples[syl] + [features[:, i:j] for i, j in samples_ix] # Train models for syl, samps in tqdm.tqdm(samples.items()): if samps: samps_concat = np.concatenate(samps, axis=1) lengths = np.array([s.shape[1] for s in samps]) self.models[syl].fit(samps_concat.T, lengths) self.trained = True
[docs] def predict(self, file_paths, onsets=None, sr=None): """ Predict bōl/solkattu transcription for list of input audios at <file_paths>. :param file_paths: Either one file_path or list of file_paths to audios to predict on :type file_paths: list or string :param onsets: list representing onsets in audios. If None, compiam.rhythm.akshara_pulse_tracker is used to automatically identify bōl/solkattu onsets. If passed should be a list of onset annotations, each being a list of bōl/solkattu onsets in seconds. <onsets> should contain one set of onset annotations for each file_path in <file_paths> :type onsets: list or None :param sr: sampling rate of audio to train on (default <self.sr>) :param sr: int :returns: if <file_paths> is a list, then return a list of transcriptions, each transcription of the form [(timestamp in seconds, bōl/solkattu),...]. Or if <file_paths> is a single fiel path string, return a single transcription. :rtype: list """ if not self.trained: raise ModelNotTrainedError( "Please train model before predicting using .train() method" ) if onsets: if not len(onsets) == len(file_paths): raise Exception("One onset annotation required for each file path") sr = self.sr if not sr else sr if not isinstance(file_paths, list): file_paths = list(file_paths) results = [] for i, fau in enumerate(file_paths): ot = onsets[i] if onsets else None results.append(self.predict_single(fau, onsets=ot, sr=sr)) return results[0] if len(results) == 1 else results
[docs] def predict_single(self, file_path, onsets=None, sr=None): """ Predict bōl/solkattu transcription directly from audio time series (such as for example that loaded by librosa.load) :param file_path: File path to audio to analyze :type file_path: str :param onsets: If None, compiam.rhythm.akshara_pulse_tracker is used to automatically identify bōl/solkattu onsets. If passed <onsets> should be a list of bōl/solkattu onsets in seconds :type onsets: list or None :param sr: sampling rate of audio to train on (default <self.sr>) :param sr: int :returns: bōl/solkattu transcription of form [(time in seconds, syllable),... ] :rtype: list """ sr = self.sr if not sr else sr hop_length = self.feature_kwargs["hop_length"] audio, _ = librosa.load(file_path, sr=sr) features = self.extract_features(audio, sr=sr) if not onsets: # if not onsets are passed, extract using pulse = AksharaPulseTracker() onsets = pulse.extract(file_path)["aksharaPulses"] onsets = np.append(onsets, len(audio) / sr) n_ons = len(onsets) samples_ix = [ ( int(onsets[i] * sr / hop_length), (int(onsets[i + 1] * sr / hop_length)) - 1, ) for i in range(n_ons - 1) ] samples_ix.append((samples_ix[-1][1], features.shape[1] - 1)) labels = [] for i, j in samples_ix: samp = features[:, i:j] t = round(i * self.feature_kwargs["hop_length"] / sr, 2) label = self.predict_sample(samp) labels.append((t, label)) return labels
[docs] def predict_sample(self, sample): """ Predict one sample using internal models. One sample should correspond to one bōl/solkattu :param sample: Numpy array features corresponding to <sample> (extracted using self.extract_features) :type sample: np.array :returns: bōl/solkattu label :rtype: str """ names = [] scores = [] for syl in self.models.keys(): try: scores.append(self.models[syl].score(sample.T)) names.append(syl) except NotFittedError: logger.warning( f"{syl} not fitted (no instance of {syl} in training) data. Will not be used for prediction." ) label = scores.index(max(scores)) return names[label]
[docs] def map(self, a): """ Map input bōl/solkattu, <a> to reduced bōl/solkattu vocabulary :param a: bōl/solkattu string (that must exist in self.mapping) :type a: np.array :returns: mapped bōl/solkattu label :rtype: str """ if a in self.mapping: return self.mapping[a] else: logger.warning( f"Skipping unknown syllable, {a} for training instance. Model syllables: {self.mapping.keys()}" ) return "!UKNOWN"
[docs] def get_sample_ix(self, annotations, audio, syl): """ Convert input onset annotations to list of in/out points for a specific bōl/solkattu syllable, <syl> :param annotations: onset annotations of the form [(timestamp in seconds, bōl/solkattu),... ] :type annotations: list/iterable :param audio: time series representation of audio :type audio: np.array :param syl: bōl/solkattu syllable to extract :type syl: str :returns: list or [(t1,t2),..] where t1 and t2 correspdong to in and out points of single bōls/solkattus :rtype: str """ annotations_two = annotations + [(len(audio), "!END")] zipped = zip(annotations, annotations_two[1:]) samples = [(t1, t2 - 1) for ((t1, a1), (t2, a2)) in zipped if a1 == syl] return samples
[docs] def extract_features(self, audio, sr=None): """ Convert input audio to features MFCC features :param audio: time series representation of audio :type audio: np.array :param sr: sampling rate of audio to train on (default <self.sr>) :param sr: int :returns: array of features :rtype: np.array """ sr = self.sr if not sr else sr MFCC = librosa.feature.mfcc(y=audio, sr=sr, **self.feature_kwargs) MFCC_delta = librosa.feature.delta(MFCC) features = np.concatenate((MFCC, MFCC_delta)) return features
[docs] def load_annotations(self, annotation_path): """ Load onset annotations from <annotation_path> :param annotation_path: path to onset annotations for one recording of the form (timestamp in seconds, bōl/solkattu syllable) :type annotation_path: str :returns: list of onset annotations (timestamp seconds, bōl/solkattu syllable) :rtype: list """ annotations = [] with open(annotation_path, "r") as f: reader = csv.reader(f) for row in reader: annotations.append((float(row[0]), str(row[1]).strip())) return annotations
[docs] def save(self, model_path): """ Save model at path as .pkl :param model_path: Path to save model to :type model_path: strs """ with open(model_path, "wb") as d: pickle.dump(self, d)