The Infona portal uses cookies, i.e. strings of text saved by a browser on the user's device. The portal can access those files and use them to remember the user's data, such as their chosen settings (screen view, interface language, etc.), or their login data. By using the Infona portal the user accepts automatic saving and using this information for portal operation purposes. More information on the subject can be found in the Privacy Policy and Terms of Service. By closing this window the user confirms that they have read the information on cookie usage, and they accept the privacy policy and the way cookies are used by the portal. You can change the cookie settings in your browser.
An image corresponds to a grid of pixels in digital image processing and the numerical value of each pixel represents image intensity. Characteristics and effects of image smoothing and other similar filtering operations, image enhancement, image distortion, etc. can be evaluated using local variance variation of image intensity. Image obtained after compression and blurring are examples of distorted...
ISO recently published a new image compression standard, JPEG XT, which extends the popular JPEG standard towards higher dynamic range, compression of alpha channels and lossless coding. In part 7 ofJPEG XT, a two-layer lossy image compression for HDR images isintroduced that reconstructs HDR signals by the combination of a baselayer following the legacy JPEG standard, and an extension layer thatenlarges...
Standard decompression of JPEG images produces artifacts along edges and a disturbing checkerboard pattern. To reduce these artifacts, decompression can be formulated as an image reconstruction problem within Bayesian maximum a posteriori probability framework. In this type of problem, the prior information about an image is typically given by the l1 norm of its sparse domain representation. In this...
Despite its age, JPEG (formally, Rec. ITU-T T.81 — ISO/IEC 10918-1) is still the omnipresent image file format for lossy compression of photographic images. While its rate-distortion performance is not competitive with state-of-the-art schemes like JPEG 2000 or HEVC, manifold techniques have been developed over the years to improve its compression performance. This article provides a short review...
The massive distribution and sharing of images increases the risk of privacy losses. There are several image formats, but one of the most used is JPEG. To take care of this, the JPEG standardization committee is promoting an activity on privacy and security, in order to provide protection at image level. This paper presents a mechanism to improve privacy in JPEG images by adding privacy policies inside...
In this study, the performances of JPEG (the most widely used lossy image compression standard until it was published in 1992), JPEG2000 (designed to provide superior image quality at low bit rates) and JPEG XR (aimed to reach the speed of JPEG and the quality of JPEG2000) are evaluated with an application developed in C# language which is able to use different codecs. The results show that recently...
This paper presents a low-complexity yet effective method for encoding High Dynamic Range data into two distinct Low Dynamic Range images to be subsequently lossy or losslessly compressed using any LDR image and video codec. The method and principles described herein are applicable to both still HDR images and sequences used for HDR-video creation. The peculiar features of the method allow LDR image...
This paper proposes a new idea for image compression that neither the additional information nor the complex formulas for image decompression are needed. Our method includes removing image pixel values from the equalized selected rows and columns for image compression and uses known adjacent pixel values to calculate unknown pixel values for image decompression. We experimentally found that the image...
The issue of backwards compatible image and video coding gained some attention in both MPEG and JPEG, let it be as extension for HEVC, let it be as the JPEG XT standardization initiative of the SC29WG1 committee. The coding systems work all on the principle of a base layer operating in the low-dynamic range regime, using a tone-mapped version of the HDR material as input, and an extension layer invisible...
Image compression had been extensively studied for reducing coding rate yet producing acceptable visual quality. However, there are many application scenarios where the compressed images are used for automatic recognition rather than human viewing, thus the visual quality is no longer critical for compression. SIFT features have demonstrated their utility in many recognition scenarios and SIFT-preserving...
In this paper, the performance of AVS2 based Remote Sensing (RS) image compression is provided. Remote Sensing images are with distinguished features such as high spatial resolution, and high spectral resolution. Conventional image compression algorithms such as JPEG and JPEG 2000 are mostly used in current satellites. With the comparisons of different image compression techniques i.e., JPEG , JPEG...
With the prevalence of digital cameras and increased band with, online photo collections are growing at a rapid rate. Especially larger image collections require user-friendly tools to search and browse the dataset for which standard approaches of organising images are not sufficient. In this demo paper, we present an efficient and effective approach to visualising and browsing image search results...
In this research proposed to compressed medical images in single frame file format with two different techniques - JPEG and JPEG2000. The significant advantage of JPEG2000 over normal JPEG is that the error from JPEG2000 compression is smaller than the error from JPEG. Nevertheless, both methods share a similar mishap; when the compression ratio increases, they both generate more error than the processes...
In this work the algorithm based on the most common and open-source standard JPEG is proposed. This algorithm is used for compression grayscale realistic images. Requirements for development are the following: easiness of implementation, low computational complexity and opportunity for a bit rate control.
The current trend of digital convergence leads to the need of the video decoder that should support multiple video standards such as, H.264/AVC, JPEG, MPEG-2, VC-1, and AVS on a single platform. In this paper, we present a resource-shared architecture of multiple transforms to support all five video codecs. The architecture is based on a new multi-dimensional delta mapping. Here the Inverse Discrete...
Summary form only given. Time-frequency analysis is the fundamental methodology in signal processing. It provides a description of signal in the time-frequency plane. Conventionally, in applications of time-frequency analysis, the time domain of a signal is partitioned into intervals at first. Interval by interval, one computes the local frequency spectrum in an interval and then makes signal processing...
In this paper a low cost and low power multi-mode entropy decoder is proposed. The proposed design is compatible to the entropy decoding for JPEG, MPEG-1/2/4, H.264 and VC-1 video coding standards. It adopts the code-word tables merging and sharing, and integrates the various entropy decoding into a single programmable design. To reduce the required memory space, a generic look-up table partition...
This paper presents the new high-performance circuit architecture of the transform and quantization for unified video CODEC. The proposed architecture can be applied to all kinds of transforms for the video compression standards such as JPEG, MPEG-1/2/4, H.264 and VC-1. It exploits the similarity of 4-point DCT and 8-point DCT using permutation matrices. Since our circuit accepts the transform coefficients...
Presented is an area-efficient architecture of a VLSI circuit that can perform various DCT-based transforms for a video decoder supporting multiple standards such as JPEG, MPEG-4, VC-1 and H.264. The proposed architecture uses a novel concept of a delta coefficient matrix and shares resources such as adders and shifters as much as possible. Multipliers are not included.
Set the date range to filter the displayed results. You can set a starting date, ending date or both. You can enter the dates manually or choose them from the calendar.