data_loader.py

"""
Description : Set DataSet module for Wavenet
"""
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import os
import numpy as np
from scipy.io import wavfile
from mxnet import nd
from utils import encode_mu_law
# pylint: disable=invalid-name, too-many-arguments
def load_wav(file_nm):
    """
    Description : load wav file
    """
    fs, data = wavfile.read(os.getcwd()+'/data/'+file_nm)
    return  fs, data

def data_generation(data, framerate, seq_size, mu, ctx, gen_mode=None):
    """
    Description : data generation to loading data
    """
    if gen_mode == 'sin':
        t = np.linspace(0, 5, framerate*5)
        data = np.sin(2*np.pi*220*t) + np.sin(2*np.pi*224*t)
    div = max(data.max(), abs(data.min()))
    data = data/div
    while True:
        start = np.random.randint(0, data.shape[0]-seq_size)
        ys = data[start:start+seq_size]
        ys = encode_mu_law(ys, mu)
        yield nd.array(ys[:seq_size], ctx=ctx)

def data_generation_sample(data, framerate, seq_size, mu, ctx, gen_mode=None):
    """
    Description : sample data generation to loading data
    """
    if gen_mode == 'sin':
        t = np.linspace(0, 5, framerate*5)
        data = np.sin(2*np.pi*220*t) + np.sin(2*np.pi*224*t)
    div = max(data.max(), abs(data.min()))
    data = data/div
    start = 0
    ys = data[start:start+seq_size]
    ys = encode_mu_law(ys, mu)
    return nd.array(ys[:seq_size], ctx=ctx)