SOTAVerified

Near-imperceptible Neural Linguistic Steganography via Self-Adjusting Arithmetic Coding

2020-10-01EMNLP 2020Code Available1· sign in to hype

Jiaming Shen, Heng Ji, Jiawei Han

Code Available — Be the first to reproduce this paper.

Reproduce

Code

Abstract

Linguistic steganography studies how to hide secret messages in natural language cover texts. Traditional methods aim to transform a secret message into an innocent text via lexical substitution or syntactical modification. Recently, advances in neural language models (LMs) enable us to directly generate cover text conditioned on the secret message. In this study, we present a new linguistic steganography method which encodes secret messages using self-adjusting arithmetic coding based on a neural language model. We formally analyze the statistical imperceptibility of this method and empirically show it outperforms the previous state-of-the-art methods on four datasets by 15.3% and 38.9% in terms of bits/word and KL metrics, respectively. Finally, human evaluations show that 51% of generated cover texts can indeed fool eavesdroppers.

Tasks

Reproductions