Pixels Of Cover Image Research Articles

A secure image steganography based on LSB technique and 2D chaotic maps

This paper introduces a pioneering, effective data-hiding algorithm using different sizes of cover images and different types of secret data (image, txt, and audio). The proposed algorithm is based on a hybrid 1D chaotic map combined with a 2D composite chaotic map paired with optimization and Least Significant Bits (LSB) techniques. We employ chaotic maps to create the initial embedding position vector, and LSB to hide the secret message in the cover image. The optimization technique utilizes the chaotic maps to optimize the random embedding sites, looking for value matches between the cover image pixels and the secret data bits. This partial improvement leads to a high-quality stego-image, a large embedding capacity, imperceptibility to the human eye, undetectability, and enhanced security. The outcomes of the extensive experiments show that when the payload is 4.2 bits per pixel, the peak signal-to-noise ratio value (PSNR), which expresses the visual quality, is above 30 dB. Furthermore, the experimental results illustrate that the system exhibits robustness against various types of attacks. As a final point of strength, the large key space (2^206) prevents the secret data from being resolved if stego-images are accessed by intruders or third parties. Even minor changes in key bits can significantly alter the extracted secret data, resulting in entirely different secret data.

Optimizing Data Security with Hybrid Scheme Based on LSB and DWT

One of the most popular techniques in image steganography is the Least Significant Bit (LSB) operation, which involves inserting secret data into the cover image's pixels' least significant bit. However, the amount of secret data that can be concealed in the cover image depends on the number of bits used for embedding. In this paper, a novel hybrid steganographic system based on Discrete Wavelet Transform (DWT) and Least Significant Bit (LSB) for image steganography is proposed. The proposed scheme aims to optimize data security by utilizing LSB and DWT techniques to embed secret data into an image robustly and efficiently. The present paper focuses on evaluating the algorithm performance by comparing the encrypted image quality using metrics such as PSNR, RMSE, and SSIM. The experimental results showed that the suggested method outperforms the existing LSB-based in terms of security performance. These results indicated that the proposed method consistently outperforms the conventional LSB-based method across all bit depths tested, with an overall improvement of 14.12% in PSNR, 41.87% in RMSE, and 4.02% in SSIM over the traditional LSB. The proposed method enhanced the PSNR values, reduced the RMSE values, and increased the SSIM values for all bit depths tested, indicating higher image fidelity, less distortion, and better preservation of structural similarity of the original image.

Dynamic Information-Hiding Method with High Capacity Based on Image Interpolating and Bit Flipping.

In this era of rapid information exchange in public networks, there is a risk to information security. Data hiding is an important technique for privacy protection. Image interpolation is an important data-hiding technique in image processing. This study proposed a method called neighbor mean interpolation by neighboring pixels (NMINP) that calculates a cover image pixel by neighbor mean interpolation and neighboring pixels. To reduce image distortion, NMINP limits the number of bits when embedding secret data, making NMINP have a higher hiding capacity and peak signal-to-noise ratio (PSNR) than other methods. Furthermore, in some cases, the secret data are flipped, and the flipped data are treated in ones' complement format. A location map is not needed in the proposed method. Experimental results comparing NMINP with other state-of-the-art methods show that NMINP improves the hiding capacity by more than 20% and PSNR by 8%.

Improved LSB image steganography with high imperceptibility based on cover‐stego matching

AbstractInformation security is an important factor when critical information is transferred. This paper concentrates on finding a method that can hide a message in an image without making any changes to it. The proposed method is novel and based on the Least Significant Bit (LSB) method with a high imperceptibility and capacity. Initially, the secret message bits are compressed using the LZW technique, then the compressed message bits are embedded into the LSB of the edge pixels in the cover image which have the same bit values. As a result, the cover image pixels remain unchanged and the stego image matches the cover image. The addresses of pixels that contain the compressed secret bits are maintained in a file called “location addresses” which the receiver uses to retrieve the compressed secret message. It is possible that the stego image will not be transmitted if it was previously specified by the sender and the receiver. Image quality metrics are applied to several standard images. The obtained PSNR for the stego image is infinity, SSIM and NCC are one, MSE and AD are zero for different embedding capacities in all images, which ensures the stego image's excellent imperceptibility.

An Efficient EMD-Based Reversible Data Hiding Technique Using Dual Stego Images

Exploiting modification direction (EMD) based data hiding techniques (DHTs) provide moderate data hiding capacity and high-quality stego images. The overflow problem and the cyclic nature of the extraction function essentially hinder their application in several fields in which reversibility is necessary. Thus far, the few EMD reversible DHTs are complex and numerically demanding. This paper presents a novel EMD-based reversible DHT using dual-image. Two novel 2 × 4 modification lookup tables are introduced, replacing the reference matrix used in similar techniques and eliminating the numerically demanding search step in similar techniques. In the embedding step, one of the modification tables modifies a pixel in odd columns in the first cover image and keeps its image in the second cover image intact. The other modification table modifies a pixel in even columns in the second cover image and keeps its image in the first cover image intact. This embedding strategy enables direct reversibility at almost zero computational cost. This technique embeds one secret digit into each pixel in the first cover image and its image in the second cover image resulting in one bit per pixel (bpp) data embedding rate. The use of the numbering system enables direct and numerically efficient conversion of the binary secret message to the and vice versa. The advantages of the proposed algorithm are straightforward reversibility, simplicity, numerical efficiency, direct conversion of the binary secret message to and vice versa, and elimination of the need for the reference matrix by replacing it with two 2 × 4 lookup tables. Simulation results show that the embedding rate of the proposed technique is one bpp. It achieved more than 49 dB average Peak to Signal Noise Ratio (PSNR) over all test images.

An asymmetric data hiding using binary pattern detected with metaheuristics algorithm

This work presents an asymmetric data hiding method using binary patterns detected with a metaheuristic algorithm. The technique uses a pheromone matrix and two stage decision process to detect binary patterns. The binary pattern acts as a secret key to isolate the complex area of the cover image from the smooth area, both the process of information hiding and information retrieval. The method hides confidential data in the complex area of cover media using the information present in the detected binary pattern and leaves the smooth area's pixel unaffected. The confidential data is hidden asymmetrically, and the asymmetry is ensured using a stego key of varying configuration and size. The binary pattern, stego key, and asymmetry of the number of bits hidden in the cover image's pixels enhance the security of confidential data by many folds. The visual analysis of the results demonstrated that the presented technique does not add any detectable modification to the resulting images and keeps the hidden data innocent for observers. The quantitative results obtained in terms of the evaluation metrics of peak signal to noise ratio, mean square error, structure similarity index, and hiding capacity, show that the proposed technique has a high value of peak signal to noise ratio and structural similarity index with a significant hiding capacity, while the mean square error is also significantly low. The high security and the quality of resulting images make it impossible for unauthorized users to obtain hidden information. Hence, the existence of confidential information is not compromised. Moreover, the comparative analysis shows that the performance of the presented technique, in terms of the evaluation metrics, is better than or comparable with state-of-the-art techniques. The binary pattern, large size, and large variety of the stego key make the proposed technique superior to the state-of-the-art techniques, in terms of security.

A New Dual Image Based Reversible Data Hiding Method Using Most Significant Bits and Center Shifting Technique

In this article, a new reversible data hiding method using most significant bits and center shifting technique in dual images is proposed. The proposed reversible data hiding method aims to securely hide high-capacity secret data. Instead of directly embedding the secret data, the method calculates new values with (n + 1) bits secret data and the n most significant bits of the cover image pixel values. Thus, it is impossible to extract secret data without obtaining the original cover image. Also, the center shifting process is performed to minimize the mean square error. After this process, the secret data to be hidden in the dual images are in the range [−3×2(n−1)+1, 3×2(n−1)−1]. The pixel values of stego images are obtained by using the secret data in this range value and cover image pixel values. As a result of experimental studies, when the payload is 2.5 bits per pixel (bpp), the peak signal-to-noise ratio value (PSNR), which expresses the visual quality, is above 34 (dB). In addition, the proposed method has proven secure against RS (regular and singular) analysis attacks.

A Binary Pattern Based Secure Data Hiding in Digital Images

Information security is one of the most challenging tasks in the recent era of advanced technologies and communication. It is important to ensure the secure exchange of confidential data. Data hiding techniques have a key role in ensuring security. The proposed technique is one such technique to enhance the security of secret information by many folds. The proposed technique detects a binary pattern to classify the cover image pixels into two groups of pixels, i.e., the group of pixels used for information hiding and the group of pixels that remains unaffected. The secret information is hidden in the selected pixels using LSB substitution without creating any detectable modifications. The results show that the technique creates a high-quality stego image with a PSNR larger than the threshold level of 30dB and SSIM higher than 0.9999. Along with the good quality of the stego images, the binary pattern enhances the security of the hidden information twofold.

Local binary pattern‐based reversible data hiding

A novel local binary pattern-based reversible data hiding (LBP-RDH) technique has been suggested to maintain a fair symmetry between the perceptual transparency and hiding capacity. During embedding, the image is divided into various 3×3 blocks. Then, using the LBP-based image descriptor, the LBP codes for each block are computed. Next, the obtained LBP codes are XORed with the embedding bits and are concealed in the respective blocks using the proposed pixel readjustment process. Further, each cover image (CI) pixel produces two different stego-image pixels. Likewise, during extraction, the CI pixels are restored without the loss of a single bit of information. The outcome of the proposed technique with respect to perceptual transparency measures, such as peak signal-to-noise ratio and structural similarity index, is found to be superior to that of some of the recent and state-of-the-art techniques. In addition, the proposed technique has shown excellent resilience to various stego-attacks, such as pixel difference histogram as well as regular and singular analysis. Besides, the out-off boundary pixel problem, which endures in most of the contemporary data hiding techniques, has been successfully addressed.

Comprehensive reversible secret image sharing with palette cover images

The comprehensive reversible cover images make secret image sharing (SIS) has more applicable scenarios, such as remote-sensing images, medical diagnosis images and so on. The previous reversible secret image sharing (RSIS) methods use binary or grayscale images as cover images. In this paper, we design an effective reversible secret image sharing method using palette cover images (RSISP). Shadow pixel values are screened to keep their 4 higher bits identical with the corresponding cover image pixel value. In the recovery phase, the original cover images are easily recovered by a bit extraction operation according to the palettes. As the experiment results show, the shadow images are comprehensive and have no pixel expansion. In addition, both the secret image and cover images can be reconstructed losslessly.

Reversible Watermarking Method with Low Distortion for the Secure Transmission of Medical Images

In telemedicine, the realization of reversible watermarking through information security is an emerging research field. However, adding watermarks hinders the distribution of pixels in the cover image because it creates distortions (which lead to an increase in the detection probability). In this article, we introduce a reversible watermarking method that can transmit medical images with minimal distortion and high security. The proposed method selects two adjacent gray pixels whose least significant bit (LSB) is different from the relevant message bit and then calculates the distortion degree. We use the LSB pairing method to embed the secret matrix of patient record into the cover image and exchange pixel values. Experimental results show that the designed method is robust to different attacks and has a high PSNR (peak signal-to-noise ratio) value. The MRI image quality and imperceptibility are verified by embedding a secret matrix of up to 262,688 bits to achieve an average PSNR of 51.657 dB. In addition, the proposed algorithm is tested against the latest technology on standard images, and it is found that the average PSNR of our proposed reversible watermarking technology is higher (i.e., 51.71 dB). Numerical results show that the algorithm can be extended to normal images and medical images.

Hardware execution of a saliency map based digital image watermarking framework

In this paper, human visual system based adaptive LSB replacement process has been used to develop an image watermarking scheme. A saliency map of the cover image is built up and the watermark is adaptively embedded into that cover image pixels to get a better visual transparency with increased payload. In this approach, the saliency map is generated by using a binary and holistic image descriptor, termed as Image Signature. The hardware execution of this proposed methodology has been set up through Virtex6 FPGA board (xc6vlx760). The experimental results divulge that the proposed framework provides less perceptual inaccuracy with improved payload capacity.

An approach for Secured Image Transmission: A High Capacitive and Confidentiality based Image Steganography using Private Stego-Key

In the proposed paper an approach for image transmission with security and also improvement of the gray-scale (8-bit image) image flexible stenographic system using LSB approach. In this process a secret key of 80 bits is applied while embedding the message into the cover image. To provide high security and also confidentiality of the data a key stego-key is applied. The proposed method the information bits are embedded adaptively into the cover-image pixels. With this method a high embedding capacity in terms of hiding the data is provided and also better imperceptibility is also achieved. The major advantage of this method verifies by the Security method of Digital Signature. It is to be verified whether the attacker has made a trials to change the Secret information in the present inside the stego-image which is intended to be kept secret throughout the communication process. In this technique the embedding process to hide the message data present in the transformed spatial domain of the cover image and makes use of a simple Exclusive-OR operation based on Security checking method of verifying the signature digitally by using key size value of 140 bits is used to check the integrity from the stego-image. The confidential data which is embedded can be retrieved from stego-images. The security level is enhanced by using the stego key and by adaptive steganography data inconspicuousness is improved.

Shared memory implementation and performance analysis of LSB steganography based on chaotic tent map

Concealing secret information in an image so that any perceptible evidence of the image alteration is insignificant, is known as image steganography. Image steganography can be implemented with either spatial or transform domain techniques. Spatial domain-based algorithms, generally the most widely used ones, refer to the process of embedding the secret information in the least significant bit positions of the cover image pixels. This paper proposes a chaotic tent map-based bit embedding as a novel steganography algorithm with a multicore implementation. The potential reasons for using chaotic maps in image steganography are sensitivity of these functions to initial conditions and control parameters. The computational complexity of the sequential least significant bit algorithm is known to be O(n). Hence, time complexity of the encryption/decryption algorithm is also a very important aspect. With the advantages offered by multicore processors, the proposed steganography algorithm can now be explicitly parallelized using the OpenMP API. As a pre-embedding operation, the quality of the randomness of the chaotic number sequences is tested with a NIST cryptographic test suite. The quality of the stego image is validated with statistical parameters such as structural similarity index (SSIM), mean square error (MSE) and peak signal-to-noise ratio (PSNR). Moreover, exploiting data parallelism inherent in the algorithm, multicore implementation of the algorithm with OpenMP API has also been reported. Proposed parallel version of the technique has been tested on five test samples of images for scalability analysis and results indicate significant speed up as compared to the sequential implementation of the technique.

Highly imperceptible data hiding technique using MSB in the grayscale image

Security of confidential information during communication in the network has been the primary concern. Therefore, data hiding techniques have become the focal point among the researchers. In this regard, to keep the communication secret, watermarking and steganography are the two most important fields of data concealing. Image steganography techniques embed the secret data bits in the image's pixels to detour attention of outsiders. In this paper, an improved data hiding technique is proposed using the XOR features of the cover image (CI) pixels to conceal the secret data bits in the least significant bit (LSB). During embedding, the most significant bits (MSBs) of the pixels are partitioned into two different segments. Next, using these segments and the embedding bits, the stego-image pixels are obtained. The comparative analysis is done with various image steganography techniques to demonstrate that the proposed work offers better imperceptibility and capacity.

Cover independent image steganography in spatial domain using higher order pixel bits

In spatial domain image steganography, Least Significant Bits (LSB) of cover image pixels are used to embed a secret message due to minimal distortion and higher payload capacity. In this paper, we have introduced an exclusive-OR (XOR) based encoding of encrypted secret message bits using varying higher-order pixel intensity bits. Encoding and LSB embedding is done block-wise by dividing the cover image into a number of blocks. The secret message is first encrypted using symmetric key cryptography and then encoded those encrypted bits by XORing them with randomly selected higher-order pixel bis of the cover image to obscure the secret bits further. Next, an inversion technique is applied to the encoded bits block-wise to keep the LSB bit changes to a minimum. The stego-key consists of the symmetric encryption key and the encode-key containing parameter settings such as the number_of_blocks, starting_block, start_pixel_offset, block_selection_rule, etc. This stego-key is shared prior to the actual communication using public-key cryptography to ensure the key’s authenticity and integrity. The extraction process does not require the cover image; the stego-image and the stego-key are sufficient. Experimental results show the visual imperceptibility along with improved image quality metrics such as Mean Square Error (MSE), Peak Signal to Noise Ratio (PSNR), Normalized Cross-Correlation (NCC), and Structural Similarity (SSIM) index in comparison to other well-known techniques. The average PSNR value remains above 51dB, even with 90% of the capacity utilized. The proposed scheme successfully eludes many standard steganalysis attacks such as histogram-based analysis (PDH), chi-square based embed probability test, Regular and Singular groups (RS) analysis, sample pair test, etc. on the tested stego-images.

Quantum steganography based on reflected gray code for color images

Digital steganography is the art and science of hiding information in covert channels, so as to conceal the information and prevent the detection of hidden messages. On the classic computer, the principle and method of digital steganography has been widely and deeply studied, and has been initially extended to the field of quantum computing. Quantum image steganography is a relatively active branch of quantum image processing, and the main strategy currently used is to modify the LSB of the cover image pixels. For the existing LSB-based quantum image steganography schemes, the embedding capacity is no more than 3 bits per pixel. Therefore, it is meaningful to study how to improve the embedding capacity of quantum image steganography. This work presents a novel steganography using reflected Gray code for color quantum images, and the embedding capacity of this scheme is up to 6 bits per pixel. In proposed scheme, the secret qubit sequence is considered as a sequence of 6-bit segments. For 6 bits in each segment, the first 3 bits are embedded into the second LSB of RGB channels of the cover image, and the remaining 3 bits are embedded into the LSB of RGB channels of the cover image using reflected-Gray code to determine the embedded bit from secret information. Following the transforming rule, the LSBs of stego-image are not always same as the secret bits and the differences are up to almost 50%. Experimental results confirm that the proposed scheme shows good performance and outperforms the previous ones currently found in the literature in terms of embedding capacity.

Using Chaotic Stream Cipher to Enhance Data Hiding in Digital Images

The growing potential of modern communications needs the use of secure means to protect information from unauthorized access and use during transmission. In general, encryption a message using cryptography techniques and then hidden a message with a steganography methods provides an additional layer of protection. Furthermore, using these combination reduces the chance of finding the hidden message. This paper proposed a system which combines schemes of cryptography with steganography for hiding secret messages and to add more complexity for steganography. The proposed system secret message encoded with chaotic stream cipher and afterwards the encoded data is hidden behind an RGB or Gray cover image by modifying the kth least significant bits (k-LSB) of cover image pixels. The resultant stego-image less distorters. After which can be used by the recipient to extract that bit-plane of the image. In fact, the schemes of encryption/decryption and embedding/ extracting in the proposed system depends upon two shred secret keys between the sender and the receiver. An experiment shows that using an unauthorized secret keys between the sender and the receiver have totally different messages from the original ones which improve the confidentiality of the images.

Novel chaotic random memory indexing steganography on FPGA

Data security has been a major concern for all means of communication lately. As Steganography offers such a unique form of securing data, in this paper, two novel image steganography algorithms are proposed based on generalized chaotic maps. Only one chaotic map is employed in the first algorithm and used for one dimensional memory indexing, while two maps are employed in the second algorithm for two dimensional memory indexing. The pseudorandom numbers used for the cover image pixel’s position selection are the maps' iterative outputs. The generalization technique of logistic maps is employed adding extra degrees of freedom for the design of different chaotic behaviors, thus enhancing the security levels of the proposed algorithms. Four different image sets are employed for methods' validation. Several performance metrics such as Peak Signal to Noise Ratio (PSNR), the Mean Squared Error (MSE), the Structural Similarity Index (SSIM), Normalized Cross Correlation (NCC) and the Image Fidelity (IF) are employed to compare between both methods. The high efficiency of the proposed algorithms compared to other work in literature is validated. The hardware designs of the two algorithms are implemented on Xilinx Virtex 7 FPGA board, achieving 350 MHz frequency.

Combining Digital Signature with Local Binary Pattern-Least Significant Bit Steganography Techniques for Securing Medical Images

The image authentication is generally based on two different types of techniques: watermarking and digital signature. In watermarking methods, embedded watermarking is often imperceptible and it contains either a specific ID of producer or codes related to content that are used for authentication. Normally a separate file is stored, digital signature is a non-repudiation and encrypted version of the information extracted from the data. A digital signature can be attached to the data to prove the originality and integrity. The proposed work presents a new approach to steganography of medical images that uses modified Least Significant Bit (LSB) based on the Local Binary Pattern (LBP) pattern. As a first step, cover image has been divided as blocks of 3×3 non overlapping masks. Then, the pixel embedding position (clock wise or anti-clock wise) has to be identified using LBP operator. The value of the LBP operator determines how and where to embed secret image pixel. Later, using LSB method, pixel values will be embedded in the cover image pixel. In order to provide the integrity of the data, the proposed work also presents Reversible Watermarking (RW), a Digital Signature (DS) technique. The proposed algorithm of steganography experimented on few medical images and achieved better efficiency with respect to MSE and PSNR values and same is reported in this paper.