lmdbutils.py

"""
LF-Font
Copyright (c) 2020-present NAVER Corp.
MIT license
"""
import io
import os

import lmdb
import json
from PIL import Image, ImageFile

ImageFile.LOAD_TRUNCATED_IMAGES = True


def load_lmdb(lmdb_path):
    lmdb_path = os.path.join(lmdb_path)
    env = lmdb.open(
        lmdb_path,
        max_readers=32,
        readonly=True,
        lock=False,
        readahead=False,
        meminit=False,
    )
    return env


def load_json(json_path):
    with open(json_path) as f:
        meta = json.load(f)

    return meta


def read_data_from_lmdb(env, lmdb_key):
    with env.begin(write=False) as txn:
        data = txn.get(lmdb_key.encode())
        data = deserialize_data(data)

    return data


def deserialize_data(data):
    if data is None:
        return None

    buf = io.BytesIO()
    buf.write(data)
    buf.seek(0)
    img = Image.open(buf)

    unpacked_data = {
        "img": img
    }

    return unpacked_data