The Experts below are selected from a list of 243 Experts worldwide ranked by ideXlab platform
Jyotsna Kumar Mandal - One of the best experts on this subject based on the ideXlab platform.
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On the use of the Stirling Transform in image steganography
Journal of Information Security and Applications, 2019Co-Authors: Sudipta Kumar Ghosal, Jyotsna Kumar MandalAbstract:Abstract Stirling Transform (ST) is primarily used in combinatorial mathematics to convert a polynomial sequence of n non-negative integers into another integer sequence. The source sequence can also be re-generated from the target sequence based on the principle of inverse Stirling Transform (IST). This property is considered as an interesting study and has been exploited for steganography in digital images. In this paper, the cover image is decomposed into the pair (n = 2) of neighboring pixel components in row major Order. Stirling Transform (ST) converts the pair of pixel components into the pair of transformed components corresponding to red, green and blue channels. The obtained transformed components are always non-negative, which fabricates varying sizes of the secret image based on the specified payload in the range of 0.5 to 3 bpB (bits per Byte). To address the security issue, the secret image is scrambled through a simple scrambling process prior to embedding. The pixel adjustment process ensures the non-occurrence of overflow/underflow during embedding. Inverse Stirling Transform (IST) re-computes the pair of pixel components from the embedded pair of transformed components. This process is repeated till the secret information is concealed and the stego-image is produced. At the recipient end, the reverse procedure is applied to extract the concealed information from the stego-image based on the following parameters: shared PIN, system time and the one time password (OTP). Message digest obtained through MD5 algorithm is used to verify the authenticity. Simulation results ensures that the proposed scheme outperforms Chang et al.’s [17] , Xia et al.’s [18] , 3-LSB [2] and hybrid GEMD [7] schemes in terms of image quality with respect to increasing payloads.
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Improved exploiting modification direction-based steganography using dynamic weightage array
Electronics Letters, 2018Co-Authors: Shaswata Saha, Sudipta Kumar Ghosal, Anuran Chakraborty, Souvik Dhargupta, Ram Sarkar, Jyotsna Kumar MandalAbstract:An improved exploiting modification direction-based image steganography technique has been proposed. The cover image is decomposed into non-overlapping units of n pixels each to embed 2 kn -ary numbers in row major Order. Here, k is the number of bits to be embedded in each pixel. Therefore, the number of bits the message sender wants to embed is not restricted by this method. The dynamic nature of the weightage array makes the process pseudo-random by producing a different key for different message images. Experimental results ensure higher payload and reduced quality distortion of stego-images over existing schemes.
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Binomial transform based fragile watermarking for image authentication
Journal of Information Security and Applications, 2014Co-Authors: Sudipta Kr Ghosal, Jyotsna Kumar MandalAbstract:In this paper, a novel Binomial transform based fragile watermarking technique has been proposed for color image authentication. Binomial transform (BT) is applied to convert each 2 × 2 sub-image block into transform domain in row major Order. On average, two bits of authenticating watermark are fabricated on each transformed component starting from the least significant bit position (LSB-0). Inverse Binomial transform (IBT) is performed as post-embedding operation to convert each 2 × 2 transformed block back into the spatial domain. A delicate re-adjustment is performed on the first embedded component to keep the pixel components positive and less than or equal to 255 keeping the fabricated watermark unaltered. The watermark is extracted at the recipient end based on the reverse operation and is verified for authentication using a message digest. Experimental result ensures that the proposed technique obtain higher Payload and Peak Signal to Noise Ratio (PSNR) as compared to existing methods.
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legendre transform based color image authentication ltcia
International Conference on Computer Science and Information Technology, 2013Co-Authors: Jyotsna Kumar Mandal, Sudipta Kr GhosalAbstract:In this paper, a fragile watermarking technique using Legendre transform (LT) has been proposed for color image authentication (LTCIA). An initial pixel adjustment is used to ensure that it never exceeds the range of a valid pixel component. The Legendre transform (LT) is applied on each pair of pixel components of the carrier image in row major Order. The transformed components of each transformed pair are used to fabricate one/two/three watermark bits starting from the first bit position (LSB-1) based on the perceptibility of human eye on red, green and blue channel. An adjustment method has been incorporated to keep the embedded transformed components closer to the original without hampering the fabricated watermark bits. The inverse Legendre transform (ILT) is applied on each adjusted pair as post embedding operation to re-generate the watermarked image in spatial domain. At the receiving end the whole watermark can be extracted based on the reverse procedure thus authentication is done through message digest. Experimental results conform that the proposed algorithm has enhanced payload and PSNR over Varsaki et. al’s Method [1] and SDHTIWCIA [2].
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ACITY (2) - Separable Discrete Hartley Transform Based Invisible Watermarking for Color Image Authentication (SDHTIWCIA)
Advances in Computing and Information Technology, 2013Co-Authors: Jyotsna Kumar Mandal, Sudipta Kumar GhosalAbstract:In this paper a novel two-dimensional Separable Discrete Hartley Transform based invisible watermarking scheme has been proposed for color image authentication (SDHTIWCIA). Two dimensional SDHT is applied on each 2 × 2 sub-image block of the carrier image in row major Order. Two bits are embedded in second, third and fourth frequency components of each 2 × 2 mask in transformed domain based on a secret key. Second and third bit position in each frequency coefficient has been chosen as embedding position. A delicate re-adjustment has incorporated in the first frequency component of each mask, to keep the quantum value positive in spatial domain without hampering the embedded bits. Inverse SDHT (ISDHT) is applied on each 2 × 2 mask as post embedding operation to produce the watermarked image. At the receiving end reverse operation is performed to extract the stream which is compared to the original stream for authentication. Experimental results conform that the proposed algorithm performs better than the Discrete Cosine Transform (DCT), Quaternion Fourier Transformation (QFT) and Spatio Chromatic DFT (SCDFT) based techniques.
Nabin Ghoshal - One of the best experts on this subject based on the ideXlab platform.
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DCT Based Image Authentication with Partial Noise Reduction (DCTIAPNR)
Advances in Intelligent Systems and Computing, 2013Co-Authors: Anirban Goswami, Dipankar Pal, Nabin GhoshalAbstract:The concept, proposed here, may prove to be an innovative derivation in the field of frequency domain steganography for grayscale images. Sub image blocks, each of size 2x2 in row major Order are taken from the carrier image and are passed through the process of Discrete Cosine Transform (DCT) to obtain the corresponding frequency components. In the process of embedding a single bit of secret message/image is inserted into the real part of the frequency component of 2nd, 3rd & 4th carrier image bytes of each block. The level of data obscurity scales up due to the application of a self devised hash function. It generates pseudorandom positions which control embedding and extraction of secret bits in and from the frequency components. In addition an adjustment is made on each embedded frequency component to optimally reduce the noise effect due to embedding. The results after experimenting with the proposed technique prove statistically improved performance compared to other exiting techniques.
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Two Stage Color Image Steganography Using DCT (TSCIS-DCT)
Advances in Intelligent Systems and Computing, 2013Co-Authors: Anirban Goswami, Dipankar Pal, Nabin GhoshalAbstract:In frequency domain steganography, use of color images for secret data hiding may prove to be a decisive innovation. The proposed concept uses two color images for hiding a color/gray authenticating message/image. The mathematical technique of Discrete Cosine Transform (DCT) is applied on each block of size 2x2 taken in row major Order from three color planes (Red, Green & Blue) sequentially and from two carrier images alternatively. A single secret message/image bit is fabricated within the transformed real frequency component of each source image byte except the first frequency component of each mask. The first frequency component of each block is used for re-adjustment to maintain the quantum value positive, non-fractional in spatial domain and also to reduce the integrated noise due to embedding. The pseudorandom position of embedding and subsequent extraction is generated by a logical expression. Experimental results of this technique reveal more efficiency compared to other similar technique.
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image authentication technique in frequency domain based on discrete fourier transformation iatfddft
arXiv: Cryptography and Security, 2012Co-Authors: Nabin Ghoshal, Jyotsna Kumar MandalAbstract:In this paper a novel data embedding technique in frequency domain has been proposed using Discrete Fourier Transform (DFT) for image authentication and secured message transmission based on hiding a large volume of data into gray images. Image authentication is done by embedding message or image in frequency domain by choosing image blocks of size 2 x 2, called mask, from the source image in row major Order and transform it into the frequency domain using DFT. Three bits of authenticating message/image/message-digest are fabricated within the real parts of each source image byte except first frequency component of each mask. The dimension of authenticating image followed by message digest (MD) and the content of authenticating message/image are also embedded. Inverse DFT (IDFT) is performed on embedded data to transform embedded frequency component to spatial component. In Order to keep the quantum value positive and non negative in spatial domain a strong and robust technique is incorporated mainly on the first frequency component and sometimes on other component depends upon situations. The decoding is done by applying the reverse algorithm. Experimental results conform that the proposed algorithm performs better than DCT, QFT and SCDFT schemes.
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Steganographic Technique in Z-Domain for Image Authentication (STZ-DIA)
International Journal of Advanced Research in Computer Science, 2012Co-Authors: Nabin GhoshalAbstract: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
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A Steganographic Scheme for Color Image Authentication Using Z-Transform (SSCIAZ)
Advances in Intelligent and Soft Computing, 2012Co-Authors: Nabin Ghoshal, Soumit Chowdhury, Jyotsna Kumar MandalAbstract:This paper deals with a novel Steganographic technique which demonstrates the color image authentication in Z-domain based on the Discrete two dimensional Z-Transform. The Transform is applied on mask of sub-image block of size 2 x 2 of spatial components in row major Order for the entire image. Single bit from the authenticating secret message/image is fabricated into the real part of the frequency component of each carrier image byte. A delicate re-adjust phase is incorporated in all components of each mask after embedding, to keep the pixel values positive and non-fractional in the spatial domain. Robustness is achieved through embedding bits in variable positions of carrier image determined by a cyclic Fibonacci series. Experimental results show the enhanced performance of the proposed watermarking technique.
Il-yeol Song - One of the best experts on this subject based on the ideXlab platform.
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Adaptive row major Order: a new space filling curve for efficient spatial join processing in the transform space
Journal of Systems and Software, 2005Co-Authors: Min-jae Lee, Kyu-young Whang, Wook-shin Han, Il-yeol SongAbstract:A transform-space index indexes spatial objects represented as points in the transform space. An advantage of a transform-space index is that optimization of spatial join algorithms using these indexes can be more formal. The authors earlier proposed the Transform-Based Spatial Join algorithm that joins two transform-space indexes. It renders global optimization easy with little overhead by utilizing the characteristics of the transform space. In particular, it allows us to globally determine the Order of accessing disk pages, which makes a significant impact on the performance of joins. For this purpose, we use various space filling curves. In this paper, we propose a new space filling curve called the adaptive row major Order (ARM Order). The ARM Order adaptively controls the Order of accessing pages and significantly reduces the one-pass buffer size (the minimum buffer size required for guaranteeing one disk access per page) and the number of disk accesses for a given buffer size. Through analysis and experiments, we verify excellence of the ARM Order when used with the Transform-Based Spatial Join. The Transform-Based Spatial Join with the ARM Order always outperforms those with other conventional space filling curves in terms of both measures used: the one-pass buffer size and the number of disk accesses. Specifically, it reduces the one-pass buffer size by up to 25.9 times and the number of disk accesses by up to 2.11 times. We conclude that we achieve these results mainly due to global optimization of the Order of accessing disk pages using an adaptive space filling curve.
Shanmuganathan Raman - One of the best experts on this subject based on the ideXlab platform.
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WACV - Simultaneous Detection and Removal of Dynamic Objects in Multi-view Images
2020 IEEE Winter Conference on Applications of Computer Vision (WACV), 2020Co-Authors: Gagan Kanojia, Shanmuganathan RamanAbstract:Consider a set of images of a scene consisting of moving objects captured using a hand-held camera. In this work, we propose an algorithm which takes this set of multi-view images as input, detects the dynamic objects present in the scene, and replaces them with the static regions which are being occluded by them. The proposed algorithm scans the reference image in the Row-Major Order at the pixel level and classifies each pixel as static or dynamic. During the scan, when a pixel is classified as dynamic, the proposed algorithm replaces that pixel value with the corresponding pixel value of the static region which is being occluded by that dynamic region. We show that we achieve artifact-free removal of dynamic objects in multi-view images of several real-world scenes. To the best of our knowledge, we propose the first method which simultaneously detects and removes the dynamic objects present in multi-view images.
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Simultaneous Detection and Removal of Dynamic Objects in Multi-view Images
arXiv: Computer Vision and Pattern Recognition, 2019Co-Authors: Gagan Kanojia, Shanmuganathan RamanAbstract:Consider a set of images of a scene consisting of moving objects captured using a hand-held camera. In this work, we propose an algorithm which takes this set of multi-view images as input, detects the dynamic objects present in the scene, and replaces them with the static regions which are being occluded by them. The proposed algorithm scans the reference image in the Row-Major Order at the pixel level and classifies each pixel as static or dynamic. During the scan, when a pixel is classified as dynamic, the proposed algorithm replaces that pixel value with the corresponding pixel value of the static region which is being occluded by that dynamic region. We show that we achieve artifact-free removal of dynamic objects in multi-view images of several real-world scenes. To the best of our knowledge, we propose the first method which simultaneously detects and removes the dynamic objects present in multi-view images.
Viktor K Prasanna - One of the best experts on this subject based on the ideXlab platform.
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Optimal dynamic data layouts for 2D FFT on 3D memory integrated FPGA
The Journal of Supercomputing, 2017Co-Authors: Ren Chen, Shreyas G. Singapura, Viktor K PrasannaAbstract:FPGAs have been widely used for accelerating various applications. For many data intensive applications, the memory bandwidth limits the performance. 3D memories with through-silicon-via connections provide potential solutions to the latency and bandwidth limitations. In this paper, we revisit the classic 2D FFT problem to evaluate the performance of 3D memory integrated FPGA. To fully utilize the fine-grained parallelism in 3D memory, data layouts which take into account the structure and organization of the memory are required. We propose dynamic data layouts for optimizing the performance of the 3D architecture. In 2D FFT, data are accessed in row major Order in the first phase, whereas the data are accessed in column major Order in the second phase. This column major Order results in high memory latency and low bandwidth due to high row activation overhead of memory. Using the proposed dynamic data layouts, we improve memory access performance in the second phase without degrading the performance of the first phase. With parallelism employed in the third dimension of the memory, data parallelism can be increased to further improve the performance. We adopt a model-based approach for 3D memory and we perform experiments on the FPGA to validate our analysis and evaluate the performance. Compared with the baseline architecture, our approach achieves up to $$40\times $$40× peak memory bandwidth utilization for columnwise FFT, thus resulting in approximately $$97\,\,\%$$97% improvement in throughput for the complete 2D FFT application.
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PaCT - Optimal Dynamic Data Layouts for 2D FFT on 3D Memory Integrated FPGA
Lecture Notes in Computer Science, 2015Co-Authors: Ren Chen, Shreyas G. Singapura, Viktor K PrasannaAbstract:FPGAs have been widely used for accelerating various applications. For many data intensive applications, the memory bandwidth can limit the performance. 3D memories with through-silicon-via connections provide potential solutions to the latency and bandwidth issues. In this paper, we revisit the classic 2D FFT problem to evaluate the performance of 3D memory integrated FPGA. To fully utilize the fine grained parallelism in 3D memory, optimal data layouts so as to effectively utilize the peak bandwidth of the device are needed. Thus, we propose dynamic data layouts specifically for optimizing the performance of the 3D architecture. In 2D FFT, data is accessed in row major Order in the first phase whereas, the data is accessed in column major Order in the second phase. This column major Order results in high memory latency and low bandwidth due to high row activation overhead of memory. Therefore, we develop dynamic data layouts to improve memory access performance in the second phase. With parallelism employed in the third dimension of the memory, data parallelism can be increased to further improve the performance. We adopt a model based approach for 3D memory and we perform experiments on the FPGA to validate our analysis and evaluate the performance. Our experimental results demonstrate upi?źto 40x peak memory bandwidth utilization for column-wise FFT, thus resulting in approximately 97i?ź% improvement in throughput for the complete 2D FFT application, compared to the baseline architecture.
