Compression of Still Images

Author(s):  
Peter Kroll ◽  
Torsten Radtke ◽  
Volker Zerbe

Data compression, and in particular image compression, plays an important role in today’s information age. Images take up over 90% of the data transfer volume on the Internet and bottlenecks like modems require heavy compression to satisfy the demands of a user. One can divide the subject of data compression into two categories: lossless compression for an exact reconstruction of the original data, and lousy compression for an approximate - as close as possible to the original - reconstruction. In this chapter we address lossless and lossy compression techniques for still images.

2016 ◽  
Vol 12 (2) ◽  
Author(s):  
Yosia Adi Jaya ◽  
Lukas Chrisantyo ◽  
Willy Sudiarto Raharjo

Data Compression can save some storage space and accelerate data transfer. Among many compression algorithm, Run Length Encoding (RLE) is a simple and fast algorithm. RLE can be used to compress many types of data. However, RLE is not very effective for image lossless compression because there are many little differences between neighboring pixels. This research proposes a new lossless compression algorithm called YRL that improve RLE using the idea of Relative Encoding. YRL can treat the value of neighboring pixels as the same value by saving those little differences / relative value separately. The test done by using various standard image test shows that YRL have an average compression ratio of 75.805% for 24-bit bitmap and 82.237% for 8-bit bitmap while RLE have an average compression ratio of 100.847% for 24-bit bitmap and 97.713% for 8-bit bitmap.


2018 ◽  
Vol 4 (12) ◽  
pp. 142 ◽  
Author(s):  
Hongda Shen ◽  
Zhuocheng Jiang ◽  
W. Pan

Hyperspectral imaging (HSI) technology has been used for various remote sensing applications due to its excellent capability of monitoring regions-of-interest over a period of time. However, the large data volume of four-dimensional multitemporal hyperspectral imagery demands massive data compression techniques. While conventional 3D hyperspectral data compression methods exploit only spatial and spectral correlations, we propose a simple yet effective predictive lossless compression algorithm that can achieve significant gains on compression efficiency, by also taking into account temporal correlations inherent in the multitemporal data. We present an information theoretic analysis to estimate potential compression performance gain with varying configurations of context vectors. Extensive simulation results demonstrate the effectiveness of the proposed algorithm. We also provide in-depth discussions on how to construct the context vectors in the prediction model for both multitemporal HSI and conventional 3D HSI data.


Author(s):  
Dave Headlam

The information age has pushed music performance into the era of music informance, in which information and performance are combined in an integrated way. The types of presentation formats and analytical information found in public music theory are ideal for music informance, and present-day explorations of informance on the Internet have a history of noted musical informants including Leonard Bernstein and Glenn Gould. In order to continue to be relevant and to thrive in our connected world, live and recorded music scenarios need to develop ever more innovative ways to enhance music performance with information effectively presented in music informance.


Author(s):  
Ferri Susanto

The students' reading comprehension is very lowat the pandemic era, Theyare difficult to understand  the text, they don’t haveEnough English vocabulary, Many teachers/lecturer used  techniques that wereless precise in teaching reading, and the students got reading comprehension scores below the minimum completion criteria (KKM). This research aims to determine whether using Reading, Encoding, Annotating, and Pondering techhnique as Learning process in pandemic era to improve reading comprehension stability for students.This research is conducted by using descriptive qualitative method, which describe of students’s problem at pandemic era by zoom in the Internet after that, analyze the data which used percentage.The researcher also has done pre-assesment for supporting accurate data.The subjects of this research were 20 students, consisted 11 females and 9 males. The subject Instrument used in this research is reading comprehension test, researcher observation cheklits and field notes, student observation Cheklist and field notes, interview and documentation by zoom at the Internet. According to avarage results, the increasing for  students' reading comprehension ability on the pre-assessment  is the average student reaches, (55.14%), learning 1  (62.15%), learning 2  (70.14%), and learning 3 (75.65%)  avarage students’ score increase and got standardization of school. Based on the result in each levels which  there is  indeed REAP technique could increasing students’ reading comprehension text.


2013 ◽  
Vol 19 ◽  
pp. 39-46
Author(s):  
Bo Zhao

The internet and other new technologies have changed personal reputation fundamentally, as seen in many similar cases regarding online defamation and privacy invasion. These changes include: a) digital reputation becomes the prevailing form of personal reputation with new characteristics; b) traditional reputational networks have been updated to online networks; c) therefore the ways for individuals to establish, maintain and defend reputations are altered in the new environment; and d) many social functions traditionally played by personal reputation have been challenged by the development of digital reputation. This article tries to provide a brief analysis of such changes and sound the warning bell. We, as citizens of the new Database Nation, have to be fully aware of such changes in order to avoid potential harms while enjoying the benefits of the information age.


2008 ◽  
Vol 67 (1) ◽  
pp. 69-91 ◽  
Author(s):  
Arthur Chaskalson

There are two themes that recur in previous Sir David Williams lectures. First, that it is a considerable honour to be invited to give the lecture. Secondly, that it is a daunting task to do so in the presence of Sir David, particularly in a field in which he has expertise. Since that covers most of the law there is no escape from this dilemma. Let me then acknowledge the privilege of having been asked to give this year's lecture, and confess that it is with some trepidation that I do so. The subject, terrorism and human rights, is not exactly uncharted territory. When I looked into the internet for some guidance on what might be relevant to terrorism and human rights, the response to my Google search informed me that in .03 seconds 32,900,000 references had been found. This seemed to indicate that it was unlikely that I would be able to say anything that has not already been said. But there are some subjects that are of such importance that there is value in reminding ourselves of the issues that are at stake, and if necessary for that purpose, repeating what others have said. And it is with that in mind that I approach my chosen topic.


2008 ◽  
Vol 2 (2) ◽  
Author(s):  
Alan Sondheim

The Internet Text is an extended analysis of the environment of Internet communication, an extended meditation on the psychology and philosophy of Net exchange. As such, it is concerned primarily with virtual or electronic subjectivity – the simultaneous presence and absence of the user, the sorts of libidinal projections that result, the nature of flamewars, and the ontological or epistemological issues that underlie these processes. Internet Text begins with a brief, almost corrosive, account of the subject – an account based on the concepts of Address, Protocol, and Recognition. This section “reduces” virtual subjectivity to packets of information, Internet sputterings, and an ontology of the self based on Otherness – your recognition of me is responsible for my Net-presence. The reduction then begins to break down through a series of further texts detailing the nature of this presence; a nature which is both sexualized/gendered, and absenting, the result of an imaginary site. Eventually, it has become clear that everything revolves around issues of the virtual subject, who is only virtual on the Net, but who has a very real body elsewhere. So Internet Text has evolved more and more in a meditation on this subject – a subject which will perhaps be one of the dominant modes of being within the next millennium. Finally, it should be noted that there are no conclusions to be drawn in Internet Text, no series of protocol statements or declarations creating any sort of ultimate defining or explanatory position. The entire history of philosophy mitigates against this; instead, I side with the Schlegels, with Nietzsche, Bataille, Jabes, and others, for whom the fragment is crucial to an understanding of contemporary life... It is dedicated to Michael Current and Clara Hielo.


2013 ◽  
Vol 824 ◽  
pp. 206-214
Author(s):  
Babatunde A. Adegboye ◽  
B.B. Bello ◽  
K.R. Ekundayo ◽  
Juliet N. Adegboye

This paper deals with data transfer from one computer to another. The serial ports of the computer are used. MAX 232 is used to convert RS 232 logic to TTL logic and then an optical transmitter circuit is used to transmit data via fiber optic cable. The optical transmitter circuit has an LED which is matched with the cable. At the receiver an optical receiver circuit is used which receives data using a photo diode and a MAX 232 again to convert TTL logic to RS 232 for the serial port at the receiving end computer. The desired baud rate can be set. Although the internet can be used, but due to its time consuming nature, one can implement data transfer using wireless medium, though at a relatively high cost. The need, therefore, is felt for fiber optic communication which is cheaper and more suitable for the task. It is cheaper than wireless medium and is prone to lesser loss as compared to wireless medium.


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