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ITU-T Rec. T.800 (08/2002) Information Technology
INTERNATIONAL TELECOMMUNICATION UNION ITU-T T.800 TELECOMMUNICATION (08/2002) STANDARDIZATION SECTOR OF ITU SERIES T: TERMINALS FOR TELEMATIC SERVICES Information technology – JPEG 2000 image coding system: Core coding system ITU-T Recommendation T.800 INTERNATIONAL STANDARD ISO/IEC 15444-1 ITU-T RECOMMENDATION T.800 Information technology – JPEG 2000 image coding system: Core coding system Summary This Recommendation | International Standard defines a set of lossless (bit-preserving) and lossy compression methods for coding bi-level, continuous-tone grey-scale, palletized color, or continuous-tone colour digital still images. This Recommendation | International Standard: – specifies decoding processes for converting compressed image data to reconstructed image data; – specifies a codestream syntax containing information for interpreting the compressed image data; – specifies a file format; – provides guidance on encoding processes for converting source image data to compressed image data; – provides guidance on how to implement these processes in practice. Source ITU-T Recommendation T.800 was prepared by ITU-T Study Group 16 (2001-2004) and approved on 29 August 2002. An identical text is also published as ISO/IEC 15444-1. ITU-T Rec. T.800 (08/2002 E) i FOREWORD The International Telecommunication Union (ITU) is the United Nations specialized agency in the field of telecommunications. The ITU Telecommunication Standardization Sector (ITU-T) is a permanent organ of ITU. ITU-T is responsible for studying technical, operating and tariff questions and issuing Recommendations on them with a view to standardizing telecommunications on a worldwide basis. The World Telecommunication Standardization Assembly (WTSA), which meets every four years, establishes the topics for study by the ITU-T study groups which, in turn, produce Recommendations on these topics. -
Randomized Lempel-Ziv Compression for Anti-Compression Side-Channel Attacks
Randomized Lempel-Ziv Compression for Anti-Compression Side-Channel Attacks by Meng Yang A thesis presented to the University of Waterloo in fulfillment of the thesis requirement for the degree of Master of Applied Science in Electrical and Computer Engineering Waterloo, Ontario, Canada, 2018 c Meng Yang 2018 I hereby declare that I am the sole author of this thesis. This is a true copy of the thesis, including any required final revisions, as accepted by my examiners. I understand that my thesis may be made electronically available to the public. ii Abstract Security experts confront new attacks on TLS/SSL every year. Ever since the compres- sion side-channel attacks CRIME and BREACH were presented during security conferences in 2012 and 2013, online users connecting to HTTP servers that run TLS version 1.2 are susceptible of being impersonated. We set up three Randomized Lempel-Ziv Models, which are built on Lempel-Ziv77, to confront this attack. Our three models change the determin- istic characteristic of the compression algorithm: each compression with the same input gives output of different lengths. We implemented SSL/TLS protocol and the Lempel- Ziv77 compression algorithm, and used them as a base for our simulations of compression side-channel attack. After performing the simulations, all three models successfully pre- vented the attack. However, we demonstrate that our randomized models can still be broken by a stronger version of compression side-channel attack that we created. But this latter attack has a greater time complexity and is easily detectable. Finally, from the results, we conclude that our models couldn't compress as well as Lempel-Ziv77, but they can be used against compression side-channel attacks. -
Conversion Principles and Circuits
Interfacing Analog and Digital Worlds: Conversion Principles and Circuits Nimal Skandhakumar Faculty of Technology University of Sri Jayewardenepura 2019 1 From Analog to Digital to Analog 2 Analog Signal ● A continuous signal that contains 1. Continuous time-varying quantities, such as 2. Infinite range of values temperature or speed, with infinite 3. More exact values, but more possible values in between difficult to work with ● Can be used to measure changes in some physical phenomena, such as light, sound, pressure, or temperature. 3 Analog Signal ● Advantages: 1. Major advantages of the analog signal is infinite amount of data. 2. Density is much higher. 3. Easy processing. ● Disadvantages: 1. Unwanted noise in recording. 2. If we transmit data at long distance then unwanted disturbance is there. 3. Generation loss is also a big con of analog signals. 4 Digital Signal ● A type of signal that can take on a 1. Discrete set of discrete values (a quantized 2. Finite range of values signal) 3. Not as exact as analog, but easier ● Can represent a discrete set of to work with values using any discrete set of waveforms; and we can represent it like (0 or 1), (on or off) 5 Difference between analog and digital signals Analog Digital Signalling Continuous signal Discrete time signal Data Subjected to deterioration by noise during Can be noise-immune without deterioration transmissions transmission and write/read cycle. during transmission and write/read cycle. Bandwidth Analog signal processing can be done in There is no guarantee that digital signal real time and consumes less bandwidth. processing can be done in real time and consumes more bandwidth to carry out the same information. -
JPEG and JPEG 2000
JPEG and JPEG 2000 Past, present, and future Richard Clark Elysium Ltd, Crowborough, UK [email protected] Planned presentation Brief introduction JPEG – 25 years of standards… Shortfalls and issues Why JPEG 2000? JPEG 2000 – imaging architecture JPEG 2000 – what it is (should be!) Current activities New and continuing work… +44 1892 667411 - [email protected] Introductions Richard Clark – Working in technical standardisation since early 70’s – Fax, email, character coding (8859-1 is basis of HTML), image coding, multimedia – Elysium, set up in ’91 as SME innovator on the Web – Currently looks after JPEG web site, historical archive, some PR, some standards as editor (extensions to JPEG, JPEG-LS, MIME type RFC and software reference for JPEG 2000), HD Photo in JPEG, and the UK MPEG and JPEG committees – Plus some work that is actually funded……. +44 1892 667411 - [email protected] Elysium in Europe ACTS project – SPEAR – advanced JPEG tools ESPRIT project – Eurostill – consensus building on JPEG 2000 IST – Migrator 2000 – tool migration and feature exploitation of JPEG 2000 – 2KAN – JPEG 2000 advanced networking Plus some other involvement through CEN in cultural heritage and medical imaging, Interreg and others +44 1892 667411 - [email protected] 25 years of standards JPEG – Joint Photographic Experts Group, joint venture between ISO and CCITT (now ITU-T) Evolved from photo-videotex, character coding First meeting March 83 – JPEG proper started in July 86. 42nd meeting in Lausanne, next week… Attendance through national -
8 Video Compression Codecs
ARTICLE VIDEO COMPRESSION CODECS: A SURVIVAL GUIDE Iain E. Richardson, Vcodex Ltd., UK 1. Introduction Not another video codec! Since the frst commercially viable video codec formats appeared in the early 1990s, we have seen the emergence of a plethora of compressed digital video formats, from MPEG-1 and MPEG-2 to recent codecs such as HEVC and VP9. Each new format offers certain advantages over its predecessors. However, the increasing variety of codec formats poses many questions for anyone involved in collecting, archiving and delivering digital video content, such as: ■■ Which codec format (if any) is best? ■■ What is a suitable acquisition protocol for digital video? ■■ Is it possible to ensure that early ‘born digital’ material will still be playable in future decades? ■■ What are the advantages and disadvantages of converting (transcoding) older formats into newer standards? ■■ What is the best way to deliver video content to end-users? In this article I explain how a video compression codec works and consider some of the practi- cal concerns relating to choosing and controlling a codec. I discuss the motivations behind the continued development of new codec standards and suggest practical measures to help deal with the questions listed above. 2. Codecs and compression 2.1 What is a video codec? ‘Codec’ is a contraction of ‘encoder and decoder’. A video encoder converts ‘raw’ or uncom- pressed digital video data into a compressed form which is suitable for storage or transmission. A video decoder extracts digital video data from a compressed fle, converting it into a display- able, uncompressed form. -
File Format Guidelines for Management and Long-Term Retention of Electronic Records
FILE FORMAT GUIDELINES FOR MANAGEMENT AND LONG-TERM RETENTION OF ELECTRONIC RECORDS 9/10/2012 State Archives of North Carolina File Format Guidelines for Management and Long-Term Retention of Electronic records Table of Contents 1. GUIDELINES AND RECOMMENDATIONS .................................................................................. 3 2. DESCRIPTION OF FORMATS RECOMMENDED FOR LONG-TERM RETENTION ......................... 7 2.1 Word Processing Documents ...................................................................................................................... 7 2.1.1 PDF/A-1a (.pdf) (ISO 19005-1 compliant PDF/A) ........................................................................ 7 2.1.2 OpenDocument Text (.odt) ................................................................................................................... 3 2.1.3 Special Note on Google Docs™ .......................................................................................................... 4 2.2 Plain Text Documents ................................................................................................................................... 5 2.2.1 Plain Text (.txt) US-ASCII or UTF-8 encoding ................................................................................... 6 2.2.2 Comma-separated file (.csv) US-ASCII or UTF-8 encoding ........................................................... 7 2.2.3 Tab-delimited file (.txt) US-ASCII or UTF-8 encoding .................................................................... 8 2.3 -
DICOM PS3.5 2021C
PS3.5 DICOM PS3.5 2021d - Data Structures and Encoding Page 2 PS3.5: DICOM PS3.5 2021d - Data Structures and Encoding Copyright © 2021 NEMA A DICOM® publication - Standard - DICOM PS3.5 2021d - Data Structures and Encoding Page 3 Table of Contents Notice and Disclaimer ........................................................................................................................................... 13 Foreword ............................................................................................................................................................ 15 1. Scope and Field of Application ............................................................................................................................. 17 2. Normative References ....................................................................................................................................... 19 3. Definitions ....................................................................................................................................................... 23 4. Symbols and Abbreviations ................................................................................................................................. 27 5. Conventions ..................................................................................................................................................... 29 6. Value Encoding ............................................................................................................................................... -
JBIG-Like Coding of Bi-Level Image Data in JPEG-2000
ISO/IEC JTC 1/SC 29/WG1 N1014 Date: 1998-10- 20 ISO/IEC JTC 1/SC 29/WG 1 (ITU-T SG8) Coding of Still Pictures JBIG JPEG Joint Bi-level Image Joint Photographic Experts Group Experts Group TITLE: Report on Core Experiment CodEff26: JBIG-Like Coding of Bi-Level Image Data in JPEG-2000 SOURCE: Faouzi Kossentini ([email protected]) and Dave Tompkins Department of ECE, University of BC, Vancouver, BC, Canada V6T 1Z4 Soeren Forchhammer ([email protected]), Bo Martins and Ole Jensen Department of Telecommunication, TDU, Lyngby, Denmark, DK-2800 Ian Caven, Image Power Inc., Vancouver, BC, Canada V6E 4B1 Paul Howard, AT&T Labs, NJ, USA PROJECT: JPEG-2000 STATUS: Core Experiment Results REQUESTED ACTION: Discussion DISTRIBUTION: 14th Meeting of ISO/IEC JTC1/SC 29/WG1 Contact: ISO/IEC JTC 1/SC 29/WG 1 Convener - Dr. Daniel T. Lee Hewlett-Packard Company, 11000 Wolfe Road, MS42U0, Cupertion, California 95014, USA Tel: +1 408 447 4160, Fax: +1 408 447 2842, E-mail: [email protected] 2 1. Update This document updates results previously reported in WG1N863. Specifically, the upcoming JBIG-2 Verification Model (VM) was used to generate the compression rates in Table 1. These results more accurately reflect the expected bit rates, and include the overhead required for the proper JBIG-2 bitstream formatting. Results may be better in the final implementation, but these results are guaranteed to be attainable with the current VM. The JBIG-2 VM will be available in December 1998. 2. Summary This document presents experimental results that compare the compression performance several JBIG-like coders to the VM0 baseline coder. -
JPEG 2000 for Video Archiving
The Pros and Cons of JPEG 2000 for Video Archiving Katty Van Mele November, 2010 Overview • Introduction – Current situation – Multiple challenges • Archiving challenges for cinema and video content • JPEG 2000 for Video Archiving • intoPIX Solutions • Conclusions INTOPIX PRIVATE & CONFIDENTIAL © 2010 JPEG 2000 SOLUTIONS 2 Current Situation • Most museums, film archiving and broadcast organizations – digitizing available content considered or initiated • Both movie content (reels) and analog video content (tapes) – Digitization process and constraints are very different. – More than 10.000.000 Hours Film (analog = film) • 30 to 40 % will disappear in the next 10 years ( Vinager syndrom) • Digitization process is complex – More than 6.000.000H ? Video ( 90% analog = tape) • x% will disappear because of the magnetic tape (binder) • Natural digitization process taking place due to the technology evolution. • Technical constraints are easier. INTOPIX PRIVATE & CONFIDENTIAL © 2010 JPEG 2000 SOLUTIONS 3 Multiple challenges • The goal of the digitization process : – Ensure the long term preservation of the content – Ensure the sharing and commercialization of the content. • Based on these different viewpoints and needs – Different technical challenges and choices – Different workflows utilized – Different commercial constraints – Different cultural and legal issues INTOPIX PRIVATE & CONFIDENTIAL © 2010 J PEG 2000 SOLUTIONS 4 Overview • Introduction • Archiving challenges for cinema and video content – General archiving concerns – Benefits of -
JPEG 2000: March 1997: JTC 1.29.14 (ISO/IEC 15444-1 Or ITU-T Rec
JPEG 2000: March 1997: JTC 1.29.14 (ISO/IEC 15444-1 or ITU-T Rec. T.800 Nimrod Peleg Nov. 2001 Why a new standard? • Superior low bit-rate performance: below 0.25 bpp • Lossless & lossy compression under one environment • Large images: karger than 64k x 64k • Single decompression architecture (current JPEG has 44 modes ) • Transmission in noisy environments • Computer generated imagery • Compound documents compression A unified system • Intended to create a new image coding system for different types of still images: bilevel, gray level, color, multi-component. • Different characteristics: natural images, scientific, medical, remote sensing, text, rendered graphics, etc. • different imaging models: (client/server, real-time transmission, image library archival, limited buffer and bandwidth resources, etc. The Target • Low bit-rate operation with rate distortion and subjective image quality performance superior to existing standards, without sacrificing performance at other points in the rate-distortion spectrum. • Part I is an international standard since December 2000. Main Features 1/2 • Superior low bit-rate performance: below 0.25 b/p for highly detailed gray scale images • Continuous-tone and bilevel compression: various dynamic ranges (e.g., 1 to 16 bits) • Lossless and lossy compression: with embedded bit stream and allow progressive lossy to lossless buildup. • Random access and processing Main Features 2/2 • Progressive transmission by pixel accuracy and resolution • Region-of-interest (ROI) coding •Openarchitecture • Robustness to bit errors • Protective image security (watermarking, labeling, stamping, or encryption) JPEG 2000 Compression Engine Encoder and Decoder general structure System Overview 1/2 • The source image is decomposed into components. • The image components are (optionally) decomposed into rectangular tiles. -
Creating and Archiving Born Digital Video
Federal Agencies Digitization Guidelines Initiative Creating and Archiving Born Digital Video Part III. High Level Recommended Practices December 2, 2014 The FADGI Audio-Visual Working Group http://www.digitizationguidelines.govaudio-visual/ Creating and Archiving Born Digital Video III: High Level Recommended Practices By the Federal Agencies Digitization Guidelines Initiative Audio-Visual Working Group http://www.digitizationguidelines.gov/audio-visual/ Version 1.1, December 2, 2014 TABLE OF CONTENTS Introduction .............................................................................................................................................................. 4 What is this Document? .......................................................................................................................................... 4 Key to Case History References .............................................................................................................................. 4 Understanding the Recommended Practices .......................................................................................................... 4 Part 1. Advice for File Creators .............................................................................................................................. 6 Plan for High Quality Video Files and Metadata ................................................................................................... 6 RP 1.1 Select a camera and other recording equipment with the capability to capture at high quality -
1 Introduction
HELSINKI UNIVERSITY OF TECHNOLOGY Faculty of Electronics, Communications, and Automation Department of Communications and Networking Le Wang Evaluation of Compression for Energy-aware Communication in Wireless Networks Master’s Thesis submitted in partial fulfillment of the requirements for the degree of Master of Science in Technology. Espoo, May 11, 2009 Supervisor: Professor Jukka Manner Instructor: Sebastian Siikavirta 2 HELSINKI UNIVERSITY OF TECHNOLOGY ABSTRACT OF MASTER’S THESIS Author: Le Wang Title: Evaluation of Compression for Energy-aware Communication in Wireless Networks Number of pages: 75 p. Date: 11th May 2009 Faculty: Faculty of Electronics, Communications, and Automation Department: Department of Communications and Networks Code: S-38 Supervisor: Professor Jukka Manner Instructor: Sebastian Siikavirta Abstract In accordance with the development of ICT-based communication, energy efficient communication in wireless networks is being required for reducing energy consumption, cutting down greenhouse emissions and improving business competitiveness. Due to significant energy consumption of transmitting data over wireless networks, data compression techniques can be used to trade the overhead of compression/decompression for less communication energy. Careless and blind compression in wireless networks not only causes an expansion of file sizes, but also wastes energy. This study aims to investigate the usages of data compression to reduce the energy consumption in a hand-held device. By con- ducting experiments as the methodologies, the impacts of transmission on energy consumption are explored on wireless interfaces. Then, 9 lossless compression algo- rithms are examined on popular Internet traffic in the view of compression ratio, speed and consumed energy. Additionally, energy consumption of uplink, downlink and overall system is investigated to achieve a comprehensive understanding of compression in wireless networks.