Image Authentication Technique Research Articles

Image Authentication Through ZTransform with Low Energy And Bandwidth (IAZT

In this paper a Z-transform based image authentication technique termed as IAZT has been proposed to authenticate gray scale images. The technique uses energy efficient and low bandwidth based invisible data embedding with a minimal computational complexity. Near about half of the bandwidth is required compared to the traditional Z–transform while transmitting the multimedia contents such as images with authenticating message through network. This authenticating technique may be used for copyright protection or ownership verification. Experimental results are computed and compared with the existing authentication techniques like Li’s method [11], SCDFT [13], Region-Based method [14] and many more based on Mean Square Error (MSE), Peak Signal to Noise Ratio (PSNR), Image Fidelity (IF), Universal Quality Image (UQI) and Structural Similarity Index Measurement (SSIM) which shows better performance in IAZT.

A Grayscale Image Fragile Watermark Authentication System in Spatial-Domain

This study deals with devising and implementing a novel technique for image authentication and secured message transmission based on hiding large volume of data into gray scale images. A grayscale image fragile watermark authentication system in spatial-domain is proposed. First it preprocesses the watermark image and resizes it to a quarter of the size of the original image. Then, it generates a random key matrix K and 128bit message authentication code from the original image. It replaces the 128bit message authentication code for the former 128bit of K to obtain a new key matrix KH. Then, it calculates the embedded position P=KHi xor (b7,b6,b5.b4) i MOD 3. b7,b6,b5,b4 are the high 4 bits of the original images pixel. It embeds the watermark image according to P value to the lower 4 bits of the original images pixel. The system is made in experiment. The result shows the system has good imperceptibility.

Intelligent Machine Learning in Image Authentication

Image authentication techniques have recently gained great attention due to its importance for a large number of multimedia applications. Digital images are increasingly transmitted over non-secure...

Image Authentication System using LDPC and Watermarking Technique

Now a days, the rate of using digital image is increasing exponentially because of its low cost and easy manipulation property. It is obvious that digital images captured from CCD cameras or other digital image devices have to be analyzed and determined before processing it, to keep the integrity and ensure the accuracy and reliability of the digital image. We need some sort of robust methods and standard procedures that guarantee and strengthen the authenticity of digital image. Image authentication is a technique that analyzes a digital image and determines whether it is altered or not. Image authentication technique is very useful for various organizations such as health care, law enforcement agencies and insurance sector etc. Image authentication is also important in content delivery via untrusted intermediaries, such as peer-to-peer (P2P) file sharing. Untrusted intermediaries might tamper the contents of image. Distinguishing the legitimate diversity of encodings from malicious manipulation is the challenge addressed in this paper. We developed a LDPC and watermark based new approach for image authentication. With the help of this approach we can authenticate images effectively. In our technique, we provide LDPC quantized image projection and the Encrypted image as authentication data. As well as watermark image that was embedded into original image to identify legitimate or illegitimate state of image authentication system. These data can be correctly decoded only with the help of an authentic image as side information. This technique provides the desired robustness against legitimate encoding alteration, while detecting illegitimate variations.

Implementation of Technique for Image Authentication using Regular LDPC Codes

In this paper, we propose an approach using encryption technique and LDPC source coding for the image authentication problem. Image authentication is important in content delivery via untrusted intermediaries, such as peer-topeer (P2P) file sharing. Many differently encoded versions of the original image might exist. In addition, intermediaries might tamper with the contents. Distinguishing legitimate diversity from malicious manipulations is the challenge addressed in this research. The key idea is to provide a Slepian-Wolf encoded quantized image projection as authentication data which is again encrypted using a secret key cryptography before ready to send. This can be correctly decoded with the help of an authentic image as side information. This mechanism provides the desired robustness against legitimate variations while detecting illegitimate modification. The decoder incorporating expectation maximization (EM) algorithms can authenticate images which have undergone contrast, brightness and even warping adjustments. Our novel authentication system also others tampering localization by using inference over a factor graph that represents tampering models.

Color image authentication with tamper detection and remedy based on BCH and Bayer Pattern

This paper proposes a new color image authentication scheme, aiming at tamper detection and recovery, based on error correction coding and Bayer Pattern. The bit stream generated by coding an image block with BCH (15,7) is treated as the authentication information while the Bayer Pattern technique is adopted to achieve tamper remedy. The service of tamper remedy is valuable in saving the bandwidth of image re-transmitting, seldom addressed in existing image authentication schemes. The experimental results show the performance in sensitive integrity detection, accurate localization and imperceptible remedy. Security of image authentication techniques is achieved only when the false positive/negative probability is taken into consideration as well as guaranteeing detection, localization and remedy. In the end, the security of the present scheme is analyzed.

An Image Authentication Technique in Frequency Domain using Genetic Algorithm (IAFDGA)

In this paper Genetic Algorithm based image authentication technique in frequency domain using Z transformation (IAFDGA) has been proposed.A 2×2 mask is taken from the source image in row major order. Z transformation is applied to transform it into freque ncy domain. Six bits are embedded in each sub mask into the second and third transformed coefficients. The sub mask is then transformed into spatial domain using inverse Z transform. Embedded image mask of size 32 bits are taken as initial population. New Generation followed by Crossover and Mutation are applied on it.To obtain New Generation , minimum coefficient of the mask is chosen, if the minimum coefficient is negative then subtract the minimum coefficient from each coefficient of the mask so that ex traction of hidden bits are ensured. For the Crossover operation consecutive bit -wise XOR is performed on the rightmost three bits of each byte in three steps. It will form a triangular form and the first bit of each step is taken as the output. Right most two LSBs of two consecutive pixels are swapped with each other as a part of Mutation operation. Genetic algorithm is applied to enhance a layer of security level. At the time of embedding dimension of the authenticating image followed by the content are e mbedded. Reverse process is followed at the time of extraction. High PSNR obtained for various images compared to existing Chin -Chen Chang et al.[2] conform the quality of invisible watermark IAFDGA. Large capacity as compared to existing algorithm [1] ensured the high payload of the scheme.

Digital Signature Scheme for Image

Image authentication techniques have recently gained great attention due to its importance for a large number of multimedia applications. Digital images are increasingly transmitted over non-secure channels such as the Internet. Therefore, military, medical and quality control images must be protected against attempts to manipulate them; such manipulations could tamper the decisions based on these images. To protect the authenticity of multimedia images, several approaches have been proposed. These approaches include conventional cryptography, fragile and semi-fragile watermarking and digital signatures that are based on the image content. The aim of this paper is to present emerging technique for image authentication. It also introduces the new concept of image content authentication and discusses the most important requirements for an effective image authentication system design. Methods which are described provide strict or selective authentication, tamper detection, localization and reconstruction capabilities and robustness against different desired image processing operations.(1)

An Image Authentication Technique by Handwritten Signature Verification using DWT and ANN

Image authentication is important in content delivery to preserve originality as well as integrity of data. Using handwritten signature we can authenticate a person accurately. This paper proposes an efficient image authentication technique by hiding handwritten signature image in selected DWT sub-band of the image. At the receiver end signature image is extracted and verified with template signature using Artificial Neural Network and hence image authentication is achieved. General Terms Image Authentication, Handwritten Signature verification

Steganographic Technique in Z-Domain for Image Authentication (STZ-DIA)

This paper deals with a novel technique for image authentication in Z-domain based on the Discrete two dimensional Z-Transform. The Z-Transform is exploits on sub-image block called mask of size 2 x 2 for frequency components of the corresponding spatial component in row major order. Multimedia Image authentication is done by hiding secret message/image into the real part of the component obtained by discrete two dimensional Z-Transform of the carrier image. A single bit from the authenticating image/message is embedded in middle and low quantum value of carrier image mask. Robustness is achieved through embedding bits in variable positions of carrier image determined by the decimal value of sum of higher three bits of frequency values (i.e. b7+b6+b5). After embedding, a delicate re-adjust phase is incorporated in all frequency components of each mask, to keep the pixel values positive and non-fractional in the spatial domain. The invisibility is conformed by using delicate re-adjust phase. This technique is also applicable for secrete data transmission through carrier color image by hiding secrete data. Experimental results show the robustness and performance of the proposed watermarking technique. Keywords: Z-Transform, Inverse Z-Transform, DFT, QFT, DCT

Content‐based image authentication by feature point clustering and matching

ABSTRACTDigital multimedia makes fabricating and copying much easier than ever before. Therefore, it demands efficient and automatic techniques to identify and verify the content of digital multimedia. Image authentication is such a technique to automatically identify whether the query image is a fabrication or a simple copy of the original one. In this paper, we propose a perceptual image authentication technique based on clustering and matching of feature points of images. Feature points are first extracted from images with the k‐largest local total variations and clustered using Fuzzy C‐means clustering algorithm. Then, feature points in the query image and the anchor image are matched into pairs in zigzag ordering along the diagonals of the images cluster by cluster. In the mean time, the outliers of feature points are removed. Then, the system decisions about the authenticity of images are determined by the majority vote of whether three types of distance between matched feature point pairs are larger than their respective thresholds. The three types of distance include the following: (i) histogram‐weighted distance, which is proposed in this paper; (ii) the normalized Euclidean distance; and (iii) the Hausdorff distance. The geometric transform between the query image and the anchor image is estimated, and the query image is registered. The possible tampered image blocks are detected, and the percentage of the tampered area is roughly estimated. The experimental results show the effectiveness and robustness of the proposed image authentication system. Copyright © 2011 John Wiley & Sons, Ltd.

Digital image forgery detection and estimation by exploring basic image manipulations

In this modern age in which we are living, digital images play a vital role in many application areas. But at the same time the image retouching techniques has also increased which forms a serious threat to the security of digital images. To cope with this problem, the field of digital forensics and investigation has emerged and provided some trust in digital images. In this paper we proposed a technique for image authentication that detects the manipulations that are done in the digital images. In most of the image forgeries such as copy-and-paste forgery, region duplication forgery, image splicing forgery etc basic image operations or manipulations are often involved. Thus if there exists the evidence for basic image alterations in digital images we can say that the image has been altered. This paper aims at detecting the basic image operations such as re-sampling (rotation, rescaling), contrast enhancement and histogram equalization which are often done in forged images. The available interpolation related spectral signature method is used for detecting rotation and rescaling and for estimating parameters such as rotation angle and rescale factors. This rotation/rescaling detection method detects some unaltered images as altered one when the images are JPEG compressed. We have overcome that problem by adding noise in the input images. We have also used the existing fingerprint detection technique for detecting contrast enhancement and histogram equalization. Besides the techniques discussed in the existing method, we identified a unique property for histogram equalization which can help us to differentiate contrast enhancement from histogram equalization. This work is tested in USC-SIPI database which consists of general unaltered images and achieved results with satisfactory accuracy.

스마트폰 사용자 인증을 위한 카메라 영상 프레임 비교에 관한 연구

스마트폰을 기반으로 한 앱은 병원의 의료 서비스, 은행 및 카드사의 금융서비스, 기업 및 가정의 유비쿼터스 기술 등 다양한 영역에 활용되고 있다. 이러한 서비스 환경에서 외부인에 의한 스마트폰의 불법적인 노출은 공 사적 정보의 유출을 포함한 자산의 손실이 발생한다. 이를 위한 보호 기법으로 비밀키 및 패턴 인식 기술, 정적인 단일 영상인증 기법이 적용되고 있으나 정적인 킷값의 유출 또는사진과같은영상을활용하여접근이가능하다는문제를 가지고 있다. 본 논문에서는 이러한 위험요소 및 문제로부터 스마트폰을 보호하기 위한 기술로 사용자 얼굴 인증 기술을 제안한다. 제안 기술은 사용자의 얼굴 동영상의 키 프레임을 실시간으로 추출하여 사용자를 인증하고 스마트폰의 접근을 제어한다. 인증 정보는 다수의 키 프레임으로 구성되며, 영상의 화소 및 휘도의 DC 값을 활용한 유사도 판별 알고리즘으로 사용자의 접근을 통제한다. APP based on the smart phone is being utilized to various scopes such as medical services in hospitals, financing services at banks and credit card companies, and ubiquitous technologies in companies and homes etc. In this service environment, exposures of smart phones cause loss of assets including leaks of official/private information by outsiders. Though secret keys, pattern recognition technologies, and single image authentication techniques are being applied as protective methods, but they have problems in that accesses are possible by utilizing static key values or images like pictures. Therefore, this study proposes a face authentication technology for protecting smart phones from these dangerous factors and problems. The proposed technology authenticates users by extracting key frames of user's facial images by real time, and also controls accesses to the smart phone. Authentication information is composed of multiple key frames, and the user' access is controlled by distinction algorism of similarity utilizing DC values of image's pixel and luminance.

Hardware implementation of invisible image watermarking algorithm using secured binary image authentication technique

In information security, the authentication and detection of tampering and forgery are of primary concern. Data hiding or watermarking for binary images authentication is a promising approach to alleviate these concerns. Even the use of a secret static key is not secured due to various attacks. To mitigate the damage of secret key exposure, key updating signature schemes can be used. Key updating is done using a one-way function. The one-way function used in this paper is the message-digest 5 (MD5) hash function. MD5 provide a unique relationship between the input and the output hash value. An additional string of data is appended with this hash value to represent the time elapsed and hence makes the key 140-bit long, which will vary dynamically. The objective is to develop real time, reliable and secure watermarking systems, which can be achieved through hardware implementations. In this paper, we present a hardware implementation of an invisible spatial domain image watermarking algorithm with dynamic key updating for binary image. The proposed architectures were modelled, simulated and synthesised in Xilinx ISE.

Image authentication with tampering localization based on watermark embedding in wavelet domain

An image authentication and tampering localization technique based on a wavelet-based digital watermarking procedure [Opt. Express 3(12), 491-496 (1998)] is proposed. To determine whether a given watermarked image has been tampered with or not, the similarity between the extracted and embedded watermarks is measured. If the similarity is less than a threshold value, the proposed sequential watermark alignment based on a coefficient stamping (SWACS) scheme is used to determine the modified wavelet coefficients corresponding to the tampered region. Then, the morphological region growing and subband duplication (MRGSD) scheme are used to include neighboring wavelet coefficients and then duplicate the wavelet coefficients in other subbands. The experimental results show that the proposed SWACS and MRGSD schemes can efficiently identify different types of image tampering. Moreover, the detection performance of the proposed system on various sizes of the watermark and tampered region is also evaluated.

Binary Document Image Authentication Watermarking Technique Based on Hierarchical Structure

A concept of pixel spread deviation (PSD) is defined to measure the"flippability"of the pixels in binary document images,and a corresponding fragile watermarking technique for image authentication and ownership verification is proposed.According to the hierarchical structure,we divide the image into blocks in a multi-level hierarchy,then calculate and embed the block watermarks in each hierarchy level,respectively.The pixels in the image are divided into two groups determined by PSD:one is"the pixels that can be flipped" and the other is "the pixels that cannot be flipped".The values of the pixels that cannot be flipped are mapped into the initial value of the chaotic system,and then the watermark can be obtained by iterating the chaotic system from the initial value.The pixels that can be flipped are substituted by the watermark to obtain the watermarked image.Experimental results show the imperceptibility of the watermarking process,the effective protection of the uniform regions in the binary image,and successful detection and localization of content modifications with multi-level authentication.

A Novel Technique for Image Authentication in Frequency Domain Using Discrete Fourier Transformation Technique (IAFDDFTT)

In this paper a novel technique for Image Authentication in Frequency Domain using Discrete Fourier Transformation Technique (IAFDDFTT) has been proposed to authenticate a gray level PGM, TIFF image by embedding a message/image where 2 x 2 submatrix is taken as source matrix from the image matrix and transform into the frequency domain. Two bits of authenticating message/image are fabricated within the real part of each pixel, excluding the first pixel of each submatrix where the position is chosen using a hash function. The process is repeated for each submatrix on row major order to insert authenticating message/image content and 128 bits Message Digest (MD-5), generated from authenticating message/image. Inverse DFT is performed to transform the embedded image from frequency to spatial domain as final step of encoding. The decoding is done through the reverse procedure. The experimental results against statistical and visual attack has been discussed and compared with the existing steganography algorithm like S-Tools. Histogram analysis, noise analysis, and standard deviation computation of source image with embedded image shows the better results in comparison with existing S-Tools.

Methods for image authentication: a survey

Image authentication techniques have recently gained great attention due to its importance for a large number of multimedia applications. Digital images are increasingly transmitted over non-secure channels such as the Internet. Therefore, military, medical and quality control images must be protected against attempts to manipulate them; such manipulations could tamper the decisions based on these images. To protect the authenticity of multimedia images, several approaches have been proposed. These approaches include conventional cryptography, fragile and semi-fragile watermarking and digital signatures that are based on the image content. The aim of this paper is to present a survey and a comparison of emerging techniques for image authentication. Methods are classified according to the service they provide, that is strict or selective authentication, tamper detection, localization and reconstruction capabilities and robustness against different desired image processing operations. Furthermore, we introduce the concept of image content and discuss the most important requirements for an effective image authentication system design. Different algorithms are described and we focus on their comparison according to the properties cited above.

Image authentication using generalised finite automata

An effective technique for combined fragile and semi-fragile image authentication is presented. The authentication signature is extracted from image representation in the automata domain, unlike most conventional methods that are based on frequency domain. In the automata domain, the image is represented in terms of its perceptual self-similarity and can therefore survive high JPEG compression ratios. This method is also capable of changing the degree of fragility by setting the value of the image self-similarity parameter α. Furthermore, the proposed technique features an extremely compact signature length while maintaining a rather simple implementation. Experimental results are presented to demonstrate the effectiveness of the proposed technique.

Robust digital signature for multimedia authentication:a summary

Image authentication verifies the originality of an image by detecting malicious manipulations. This goal is different from that of image watermarking which embeds into the image a signature surviving most manipulations. Most existing methods for image authentication treat all types of manipulation equally (i.e., as unacceptable). However, some applications demand techniques that can distinguish acceptable manipulations (e.g., compression) from malicious ones. In this paper, we describe an effective technique for image authentication, which can prevent malicious manipulations but allow JPEG lossy compression. The authentication signature is based on the invariance of the relationship between the DCT coefficients at the same position in separate blocks of an image. This relationship will be preserved when these coefficients are quantized in a JPEG compression process. Our proposed method can distinguish malicious manipulations from JPEG lossy compression regardless of how high the compression ratio is. We also show that, in different practical cases, the design of the authenticator depends on the number of recompression times, and whether the image is decoded into integral values in the pixel domain during the recompression process. Theoretical and experimental results indicate that this technique is effective for image authentication.