tool/np.py

import math

from numba import jit
import wave
from io import BytesIO

import numpy as np
from .av import wav2



def float_to_int16(audio: np.ndarray) -> np.ndarray:
    am = int(math.ceil(float(np.abs(audio).max())) * 32768)
    am = 32767 * 32768 // am
    return np.multiply(audio, am).astype(np.int16)

def pcm_arr_to_mp3_view(wav: np.ndarray):
    buf = BytesIO()
    with wave.open(buf, "wb") as wf:
        wf.setnchannels(1)  # Mono channel
        wf.setsampwidth(2)  # Sample width in bytes
        wf.setframerate(24000)  # Sample rate in Hz
        wf.writeframes(float_to_int16(wav))
    buf.seek(0, 0)
    buf2 = BytesIO()
    wav2(buf, buf2, "mp3")
    buf.seek(0, 0)
    return buf2.getbuffer()