180 research outputs found

    Subband domain coding of binary textual images for document archiving

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    Cataloged from PDF version of article.In this work, a subband domain textual image compression method is developed. The document image is first decomposed into subimages using binary subband decompositions. Next, the character locations in the subbands and the symbol library consisting of the character images are encoded. The method is suitable for keyword search in the compressed data. It is observed that very high compression ratios are obtained with this method. Simulation studies are presented

    Validation and Data Repairing of Document Image using Steganography Method

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    This paper attempts to propose a novel technique of blind authentication based on the method of secret in addition to data repair capability for grayscale document images through the use of the Portable Network Graphics (PNG) image. For every block of a grayscale document image, an authentication signal is generated, which, along with the block content in binary, is transformed into numerous shares using the Shamir secret sharing scheme. The parameters involved are carefully selected so that as many shares as possible can be generated and embedded into an alpha channel plane. After this, the alpha channel plane is combined with the original grayscale image to yield a PNG image. During this process, the computed share values are recorded as a range of alpha channel values near their maximum value of 255 to return a transparent stego-image with a disguised effect. In the image authentication process, marking of an image block is done as tampered, if the authentication signal computed from the current block content does not match the one extracted from the shares embedded in the alpha channel plane. Each tampered block is then subjected to data repairing by a reverse Shamir scheme after collecting two shares from unmarked blocks. Procedures to protect the safety of the data that lies concealed in the alpha channel have been proposed. Decent experimental results demonstrate the efficiency of the proposed method

    A Data Hiding Method Based on Partition Variable Block Size with Exclusive-or Operation on Binary Image

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    In this paper, we propose a high capacity data hiding method applying in binary images. Since a binary image has only two colors, black or white, it is hard to hide data imperceptible. The capacities and imperception are always in a trade-off problem. Before embedding we shuffle the secret data by a pseudo-random number generator to keep more secure. We divide the host image into several non-overlapping (2n+1) by (2n+1) sub-blocks in an M by N host image as many as possible, where n can equal 1, 2, 3 , 
, or min(M,N). Then we partition each sub-block into four overlapping (n+1) by (n+1) sub-blocks. We skip the all blacks or all whites in each (2n+1) by (2n+1) sub-blocks. We consider all four (n+1) by (n+1) sub-blocks to check the XOR between the non overlapping parts and center pixel of the (2n+1) by (2n+1) sub-block, it embed n 2 bits in each (n+1) by (n+1) sub-block, totally are 4*n 2 . The entire host image can be embedded 4×n 2×M/(2n+1)×N/(2n+1) bits. The extraction way is simply to test the XOR between center pixel with their non-overlapping part of each sub-block. All embedding bits are collected and shuffled back to the original order. The adaptive means the partitioning sub-block may affect the capacities and imperception that we want to select. The experimental results show that the method provides the large embedding capacity and keeps imperceptible and reveal the host image lossless

    Application of Stochastic Diffusion for Hiding High Fidelity Encrypted Images

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    Cryptography coupled with information hiding has received increased attention in recent years and has become a major research theme because of the importance of protecting encrypted information in any Electronic Data Interchange system in a way that is both discrete and covert. One of the essential limitations in any cryptography system is that the encrypted data provides an indication on its importance which arouses suspicion and makes it vulnerable to attack. Information hiding of Steganography provides a potential solution to this issue by making the data imperceptible, the security of the hidden information being a threat only if its existence is detected through Steganalysis. This paper focuses on a study methods for hiding encrypted information, specifically, methods that encrypt data before embedding in host data where the ‘data’ is in the form of a full colour digital image. Such methods provide a greater level of data security especially when the information is to be submitted over the Internet, for example, since a potential attacker needs to first detect, then extract and then decrypt the embedded data in order to recover the original information. After providing an extensive survey of the current methods available, we present a new method of encrypting and then hiding full colour images in three full colour host images with out loss of fidelity following data extraction and decryption. The application of this technique, which is based on a technique called ‘Stochastic Diffusion’ are wide ranging and include covert image information interchange, digital image authentication, video authentication, copyright protection and digital rights management of image data in general

    Quantization Watermarking for Joint Compression and Data Hiding Schemes

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    International audienceEnrichment and protection of JPEG2000 images is an important issue. Data hiding techniques are a good solution to solve these problems. In this context, we can consider the joint approach to introduce data hiding technique into JPEG2000 coding pipeline. Data hiding consists of imperceptibly altering multimedia content, to convey some information. This process is done in such a way that the hidden data is not perceptible to an observer. Digital watermarking is one type of data hiding. In addition to the imperceptibility and payload constraints, the watermark should be robust against a variety of manipulations or attacks. We focus on trellis coded quantization (TCQ) data hiding techniques and propose two JPEG2000 compression and data hiding schemes. The properties of TCQ quantization, defined in JPEG2000 part 2, are used to perform quantization and information embedding during the same time. The first scheme is designed for content description and management applications with the objective of achieving high payloads. The compression rate/imperceptibility/payload trade off is our main concern. The second joint scheme has been developed for robust watermarking and can have consequently many applications. We achieve the better imperceptibility/robustness trade off in the context of JPEG2000 compression. We provide some experimental results on the implementation of these two schemes

    WG1N5315 - Response to Call for AIC evaluation methodologies and compression technologies for medical images: LAR Codec

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    This document presents the LAR image codec as a response to Call for AIC evaluation methodologies and compression technologies for medical images.This document describes the IETR response to the specific call for contributions of medical imaging technologies to be considered for AIC. The philosophy behind our coder is not to outperform JPEG2000 in compression; our goal is to propose an open source, royalty free, alternative image coder with integrated services. While keeping the compression performances in the same range as JPEG2000 but with lower complexity, our coder also provides services such as scalability, cryptography, data hiding, lossy to lossless compression, region of interest, free region representation and coding

    Information Hiding in Images Using Steganography Techniques

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    Innovation of technology and having fast Internet make information to distribute over the world easily and economically. This is made people to worry about their privacy and works. Steganography is a technique that prevents unauthorized users to have access to the important data. The steganography and digital watermarking provide methods that users can hide and mix their information within other information that make them difficult to recognize by attackers. In this paper, we review some techniques of steganography and digital watermarking in both spatial and frequency domains. Also we explain types of host documents and we focused on types of images

    Subband domain coding of binary textual images for document archiving

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    In this work, a subband domain textual image compression method is developed. The document image is first decomposed into subimages using binary subband decompositions. Next, the character locations in the subbands and the symbol library consisting of the character images are encoded. The method is suitable for keyword search in the compressed data. It is observed that very high compression ratios are obtained with this method. Simulation studies are presented

    Security during Transmission of Data Using Web Steganography

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    The project entitled Steganography is to give security to a content record. Since the security of the data over the internet has raised a concern to the people. There are many methods to protect the data from going into the access of unauthorized people. Steganography can be used along with the encryption technique to secure the data. Steganography is used to hide the data or a secret message whereas cryptography is used to encrypt the message and make it difficult the people to read. So, the proposed system is to combine both steganography and cryptography for the secret data transmission. The transmission can be done by using an image as a carrier of data. This paper uses high-performance BMP steganography along with a substitution encryption methodology. The approach that is used here is IDEA (International Data Encryption Algorithm) algorithm which is used for encryption. The IDEA algorithm works as follows, it will take the TEXT document and mystery key as the input and gives the encrypted and BMP picture as the output for the sender side. There can additionally be “Voice Recognition System” framework so that it can use voice to decrypt the message. This is the future expansion or scope of this paper

    A digital signature and watermarking based authentication system for JPEG2000 images

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    In this thesis, digital signature based authentication system was introduced, which is able to protect JPEG2000 images in different flavors, including fragile authentication and semi-fragile authentication. The fragile authentication is to protect the image at code-stream level, and the semi-fragile is to protect the image at the content level. The semi-fragile can be further classified into lossy and lossless authentication. With lossless authentication, the original image can be recovered after verification. The lossless authentication and the new image compression standard, JPEG2000 is mainly discussed in this thesis
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