libs/audio.py

import numpy as np
import pydub 
from re import sub

def float2pcm(sig, dtype='int16'):
    """Convert floating point signal with a range from -1 to 1 to PCM.
    Any signal values outside the interval [-1.0, 1.0) are clipped.
    No dithering is used.
    Note that there are different possibilities for scaling floating
    point numbers to PCM numbers, this function implements just one of
    them.  For an overview of alternatives see
    http://blog.bjornroche.com/2009/12/int-float-int-its-jungle-out-there.html
    Parameters
    ----------
    sig : array_like
        Input array, must have floating point type.
    dtype : data type, optional
        Desired (integer) data type.
    Returns
    -------
    numpy.ndarray
        Integer data, scaled and clipped to the range of the given
        *dtype*.
    See Also
    --------
    pcm2float, dtype
    """
    sig = np.asarray(sig)
    if sig.dtype.kind != 'f':
        raise TypeError("'sig' must be a float array")
    dtype = np.dtype(dtype)
    if dtype.kind not in 'iu':
        raise TypeError("'dtype' must be an integer type")

    i = np.iinfo(dtype)
    abs_max = 2 ** (i.bits - 1)
    offset = i.min + abs_max
    return (sig * abs_max + offset).clip(i.min, i.max).astype(dtype)

def strip_text(text: str) -> str:
    return sub(r"[^a-zA-Z0-9 ]", "", text)

def wav2ogg(x, sr, text, language, normalized=True):
    print(x,sr,text,language)
    """numpy array to MP3"""
    channels = 2 if (x.ndim == 2 and x.shape[1] == 2) else 1
    if normalized:  # normalized array - each item should be a float in [-1, 1)
        y = np.int16(x * 2 ** 15)
    else:
        y = np.int16(x)
    song = pydub.AudioSegment(y.tobytes(), frame_rate=sr, sample_width=2, channels=channels)
    path = f"/tmp/{language}-{strip_text(text)}.ogg"
    song.export(path, format="ogg", codec="libvorbis")
    # samples = song.get_array_of_samples()
    return path # np.array(samples)