utils.py 文件源码

def load_lmdb_dataset(db_name):
    X = []
    Y = []
    env = lmdb.open(db_name, readonly=True)
    with env.begin() as txn:
        cursor = txn.cursor()
        for key, value in cursor:
            datum = Datum()
            datum.ParseFromString(value)
            flat_x = np.fromstring(datum.data, dtype=np.uint8)
            X.append(flat_x.reshape(datum.channels, datum.height, datum.width))
            Y.append(datum.label)
    env.close()
    assert len(X) == len(Y)
    X = np.asarray(X)
    Y = np.asarray(Y)
    return X, Y