JPEG

About: JPEG is a research topic. Over the lifetime, 9980 publications have been published within this topic receiving 199206 citations. The topic is also known as: continuous-tone still image encoding & continuous-tone still image decoding.

A novel adaptive compression method for hyperspectral images by using EDT and particle swarm optimization

Abstract: Hyperspectral sensors generate useful information about climate and the earth surface in numerous contiguous narrow spectral bands, and are widely used in resource management, agriculture, environmental monitoring, etc. Compression of the hyperspectral data helps in long-term storage and transmission systems. Lossless compression is preferred for high-detail data, such as hyperspectral data. Due to high redundancy in neighboring spectral bands and the tendency to achieve a higher compression ratio, using adaptive coding methods for hyperspectral data seems suitable for this purpose. This paper introduces two new compression methods. One of these methods is adaptive and powerful for the compression of hyperspectral data, which is based on separating the bands with different specifications by the histogram and Binary Particle Swarm Optimization (BPSO) and compressing each one a different manner. The new proposed methods improve the compression ratio of the JPEG standards and save storage space the transmission. The proposed methods are applied on different test cases, and the results are evaluated and compared with some other compression methods, such as lossless JPEG and JPEG2000.

Universal Steganographic Detection in JPEG Image Using the Graph Laplacian Semi-supervised Kernel

Abstract: Current image steganographic detection algorithms are unable to make full use of the geometry of unlabeled image examples, detection performance is subject to a few labeled examples, which is utilized for training. In this paper, we propose an effective steganographic detection method for JPEG image that rely on the overall dataset. The method is combined with semi-supervised kernel in the presence of unlabeled examples. Semi-supervised kernel method constructs data adjacency graph to obtain Gram matrix, then we obtain the proposed method by incorporating graph Laplacian into kernel-based algorithms, which is effective integration of the cluster assumption and manifold assumption. Our method utilizes the geometry of all examples with manifold regularization to produce smooth decision functions and thus improving the performance universal steganographic detection. Experimental results show the effectiveness of our proposed method.

Method of hidden data transfer in video image

Abstract: FIELD: information technology.SUBSTANCE: invention relates to steganography and is aimed at arrangement of a channel for hidden transfer of additional information in a video image. Proposed is a method of hidden data transfer in a video image as per MPEG-2 standard based on replacing less significant bits of a video image frame with values of a two-dimensional nonlinear code combination containing the hidden information. Formation of the steganographic channel is started with embedded data processing including encoding and modulation with a pseudo-random signal, for which selected are nonlinear 2D Frank-Walsh signals and/or Frank-Krestenson signals. Simultaneously with formation of the stegosignal selected are frames for its embedding considering as suitable all I-frames, as well as B- and P-frames. Stegochannel data are embedded only in those DCT coefficients, which are located in the vicinity of the right diagonal of the DCT coefficients matrix recorded in a JPEG file and added with extra system information and with universal Huffman tables by modulo two addition of the DCT coefficient bits.EFFECT: technical result is enabling minimization of distortion of the video image, which is being introduced in, while providing stego-resistance of the information transmission system.1 cl, 7 dwg

Image processing method and apparatus

Abstract: PROBLEM TO BE SOLVED: To reduce the amount of memory necessary for decoding SOLUTION: An image processing method which decodes progressive JPEG bit streams has a step of dividing code sequences included in the bit streams into blocks that are composed of DC coefficients and AC coefficients, and variable-length-decoding the DC coefficients, and a step of variable-length-decoding the AC coefficients using the decoded DC coefficients and generating high resolution display image data COPYRIGHT: (C)2010,JPO&INPIT

Structure Preserving in X-ray Image Enhancement

Abstract: X-ray images reflect the mass of tissues and muscle that the X-ray beams pass through. These images are stored in a DICOM format where each pixel is represented in 12-bits, but commercial screens are designed to work with an 8-bits format (JPEG, PNG). To show a DICOM image, traditional methods compress the High Dynamic Range (HDR) of DICOM images to a Low Dynamic Range (LDR) of commercial screens. These methods focus on enhancing the image contrast and preserving the mass information of the original image. However, it cannot preserve the structure of the original image. The structure may be changed to enhance the sharpness. Therefore, in this article, we propose a method that enhances the image contrast and preserves the structure and mass information. We model the structure information by pairwise-pixel relationships that are embedded in a Laplacian matrix. Later, the image compression task will be modeled as an optimization problem. The solution is solved efficiently by approximating a linear system. Last but not least, we proposed a fusion mechanism on a quality domain. The fusion helps the compressed image to be robust with control parameters. The experiments proved the contributions of the proposed method in terms of contrast enhancement and structure-preserving.