# coding=utf-8
import base64

import numpy as np


def feature_to_blob(feature):
    arr = np.asarray(feature, dtype=np.float32)
    return base64.b64encode(arr.tobytes()).decode('ascii')


def blob_to_feature(blob):
    if not blob:
        return None
    try:
        raw = base64.b64decode(blob.encode('ascii') if isinstance(blob, str) else blob)
        return np.frombuffer(raw, dtype=np.float32)
    except Exception:
        return None