Quantum data hiding in the presence of noise

When classical or quantum information is broadcast to separate receivers, there exist codes that encrypt the encoded data such that the receivers cannot recover it when performing local operations and classical communication, but they can decode reliably if they bring their systems together and perform a collective measurement. This phenomenon is known as quantum data hiding and hitherto has been studied under the assumption that noise does not affect the encoded systems. With the aim of applying the quantum data hiding effect in practical scenarios, here we define the data-hiding capacity for hiding classical information using a quantum channel. Using this notion, we establish a regularized upper bound on the data hiding capacity of any quantum broadcast channel, and we prove that coherent-state encodings have a strong limitation on their data hiding rates. We then prove a lower bound on the data hiding capacity of channels that map the maximally mixed state to the maximally mixed state (we call these channels "mictodiactic"---they can be seen as a generalization of unital channels when the input and output spaces are not necessarily isomorphic) and argue how to extend this bound to generic channels and to more than two receivers.Comment: 12 pages, accepted for publication in IEEE Transactions on Information Theor

Design of information hiding algorithm for multi-link network transmission channel

Traditional channel information hiding algorithms based on m-sequence for multi-link network transmission, which apply m-sequence to channel coding information hiding system, do not analyze the upper limit of hiding capacity of multi-link network transmission channel system, and do not consider the hidden danger of overlapping secret information when embedding secret information is too large. It has the defects of low efficiency, poor accuracy and large storage cost. This paper designs an information hiding algorithm for multi-link network transmission channel based on secondary positioning, it uses RS code M public key cryptosystem to pre-process secret information and improve the security of information; calculates the upper limit of hiding capacity of multi-link network transmission channel system through information hiding capacity analysis model, and determines whether the hiding capacity exceeds the secret information. Secondary location and cyclic shift mechanism are introduced to improve the randomness of location selection and avoid overlapping of secret information. The experimental results show that the proposed algorithm has a great advantage in memory cost. When the channel SNR is 0 dB and 8 dB, the normalization coefficients are 0.87 and 1.04, respectively. This shows that the algorithm has a high accuracy in extracting secret information. The average time spent on hiding information is 2.04 s, indicating that the algorithm has high information hiding rate and storage efficiency

DCT based Reversible Information Hiding Scheme For Video using Quantized Blocks

The reversible data hiding is used for lossless and reversible streganography scheme for hiding secret data in quantized descret cosine transformation (DCT) blocks. The requirement of reversibility may lead to more modifications to the cover content which result in the tradeoff between the visual quality and hiding capacity. In this paper we propose a reversible information hiding scheme for video, to embeds the information into non-zero AC coefficients of quantized DCT blocks. The experimental results show that the proposed scheme improves both the visual quality and hiding capacity

Increasing Secret Data Hiding Capacity in QR Code Using 3X3 Subcells

The use of QR Code is becoming increasingly popular and is driven by its data storage capacity higher than a conventional horizontal barcode, fast code reading and it does not require any special scan reader so that the majority smart-phone devices nowadays are capable reading them. Based on the development of camera technology in latest smart-phone devices, Teraura and Sakurai proposed method for hiding an additional data into a fine subcell structure of a monochrome QR Code. Since in the case 3x3 subcells configuration the cover data is placed at the outer subcells and utilized a single center subcell to store one bit of embedded data and , a general QR Code reader that detects a cell of a symbol from its center pixel has difficulty to extract the cover data of a 3x3 subcells QR Code. This study proposes two alternative methodologies: compatibility mode that accommodate different approaches in recognizing a cell color and extended mode that reduce the compatibility level which only accommodate a general cell color detection method. The subcell selection is kept secret by applying pseudorandom to randomize the bit data position in each cell. Experimental results show that both proposed methods are 97% compatible to be read by a general QR Code reader. Compatible mode, uses 4 subcells to store 4 bits additional data and has 51% data density ratio. Whereas in extended mode, it uses 8 subcells to store 8 bit additional data and has has a higher 92% of data density ratio. With a bigger data density ratio, a 3x3 sucells in compatible and extended mode respectively has embedded data capacity 4 times and 8 times higher than the previous method

An enhanced Least Significant Bit Steganographic Method for Information Hiding

The least significant bit (LSB) insertion method is a simple steganographic algorithm that takes the least significant bit in some bytes of the cover medium and swaps them with a sequence of bytes containing the secret data in order to conceal the information in the cover medium. However its imperceptibility and hiding capacity are relatively low. This is as revealed by the statistical characteristics of its resultant stego images compared to the original cover images. To increase the level of imperceptibility and the hiding capacity in the LSB insertion method, this research proposes an enhanced LSB method that employs a selective and randomized approach in picking specific number of target image bits to swap with the secret data bits during the embedding process. To facilitate the selective picking of the target image bits, the standard minimal linear congruential number generator (LCG) is used. The message digest (digital signature) of a user supplied password is used to seed the LCG and to extract the message from the cover medium. In measuring the effectiveness of the proposed method, the study adopted an experimental research design where the statistical characteristics of the proposed method stego images were compared with those of the traditional LSB method in a comparative experiment designed to establish the levels of image distortion (noise) introduced in the original cover image when either of the methods is used under the same payload and image. The experiment results indicated improved levels of imperceptibility and hiding capacity in the proposed method. Key Words: Steganography, Steganalysis, Stego image, payload, imperceptibilit

High capacity steganographic method based upon JPEG

The two most important aspects of any image-based steganographic system are the quality of the stegoimage and the capacity of the cover image. This paper proposes a novel and high capacity steganographic approach based on Discrete Cosine Transformation (DCT) and JPEG compression. JPEG technique divides the input image into non-overlapping blocks of 8x8 pixels and uses the DCT transformation. However, our proposed method divides the cover image into nonoverlapping blocks of 16x16 pixels. For each quantized DCT block, the least two-significant bits (2-LSBs) of each middle frequency coefficient are modified to embed two secret bits. Our aim is to investigate the data hiding efficiency using larger blocks for JPEG compression. Our experiment result shows that the proposed approach can provide a higher information hiding capacity than Jpeg-Jsteg and Chang et al. methods based on the conventional blocks of 8x8 pixels. Furthermore, the produced stego-images are almost identical to the original cover images