45,877 research outputs found
A Revision Control System for Image Editing in Collaborative Multimedia Design
Revision control is a vital component in the collaborative development of
artifacts such as software code and multimedia. While revision control has been
widely deployed for text files, very few attempts to control the versioning of
binary files can be found in the literature. This can be inconvenient for
graphics applications that use a significant amount of binary data, such as
images, videos, meshes, and animations. Existing strategies such as storing
whole files for individual revisions or simple binary deltas, respectively
consume significant storage and obscure semantic information. To overcome these
limitations, in this paper we present a revision control system for digital
images that stores revisions in form of graphs. Besides, being integrated with
Git, our revision control system also facilitates artistic creation processes
in common image editing and digital painting workflows. A preliminary user
study demonstrates the usability of the proposed system.Comment: pp. 512-517 (6 pages
Semantic multimedia remote display for mobile thin clients
Current remote display technologies for mobile thin clients convert practically all types of graphical content into sequences of images rendered by the client. Consequently, important information concerning the content semantics is lost. The present paper goes beyond this bottleneck by developing a semantic multimedia remote display. The principle consists of representing the graphical content as a real-time interactive multimedia scene graph. The underlying architecture features novel components for scene-graph creation and management, as well as for user interactivity handling. The experimental setup considers the Linux X windows system and BiFS/LASeR multimedia scene technologies on the server and client sides, respectively. The implemented solution was benchmarked against currently deployed solutions (VNC and Microsoft-RDP), by considering text editing and WWW browsing applications. The quantitative assessments demonstrate: (1) visual quality expressed by seven objective metrics, e.g., PSNR values between 30 and 42 dB or SSIM values larger than 0.9999; (2) downlink bandwidth gain factors ranging from 2 to 60; (3) real-time user event management expressed by network round-trip time reduction by factors of 4-6 and by uplink bandwidth gain factors from 3 to 10; (4) feasible CPU activity, larger than in the RDP case but reduced by a factor of 1.5 with respect to the VNC-HEXTILE
Temporal Analysis of Activity Patterns of Editors in Collaborative Mapping Project of OpenStreetMap
In the recent years Wikis have become an attractive platform for social
studies of the human behaviour. Containing millions records of edits across the
globe, collaborative systems such as Wikipedia have allowed researchers to gain
a better understanding of editors participation and their activity patterns.
However, contributions made to Geo-wikis_wiki-based collaborative mapping
projects_ differ from systems such as Wikipedia in a fundamental way due to
spatial dimension of the content that limits the contributors to a set of those
who posses local knowledge about a specific area and therefore cross-platform
studies and comparisons are required to build a comprehensive image of online
open collaboration phenomena. In this work, we study the temporal behavioural
pattern of OpenStreetMap editors, a successful example of geo-wiki, for two
European capital cities. We categorise different type of temporal patterns and
report on the historical trend within a period of 7 years of the project age.
We also draw a comparison with the previously observed editing activity
patterns of Wikipedia.Comment: Submitte
Conflict and Computation on Wikipedia: a Finite-State Machine Analysis of Editor Interactions
What is the boundary between a vigorous argument and a breakdown of
relations? What drives a group of individuals across it? Taking Wikipedia as a
test case, we use a hidden Markov model to approximate the computational
structure and social grammar of more than a decade of cooperation and conflict
among its editors. Across a wide range of pages, we discover a bursty war/peace
structure where the systems can become trapped, sometimes for months, in a
computational subspace associated with significantly higher levels of
conflict-tracking "revert" actions. Distinct patterns of behavior characterize
the lower-conflict subspace, including tit-for-tat reversion. While a fraction
of the transitions between these subspaces are associated with top-down actions
taken by administrators, the effects are weak. Surprisingly, we find no
statistical signal that transitions are associated with the appearance of
particularly anti-social users, and only weak association with significant news
events outside the system. These findings are consistent with transitions being
driven by decentralized processes with no clear locus of control. Models of
belief revision in the presence of a common resource for information-sharing
predict the existence of two distinct phases: a disordered high-conflict phase,
and a frozen phase with spontaneously-broken symmetry. The bistability we
observe empirically may be a consequence of editor turn-over, which drives the
system to a critical point between them.Comment: 23 pages, 3 figures. Matches published version. Code for HMM fitting
available at http://bit.ly/sfihmm ; time series and derived finite state
machines at bit.ly/wiki_hm
git2net - Mining Time-Stamped Co-Editing Networks from Large git Repositories
Data from software repositories have become an important foundation for the
empirical study of software engineering processes. A recurring theme in the
repository mining literature is the inference of developer networks capturing
e.g. collaboration, coordination, or communication from the commit history of
projects. Most of the studied networks are based on the co-authorship of
software artefacts defined at the level of files, modules, or packages. While
this approach has led to insights into the social aspects of software
development, it neglects detailed information on code changes and code
ownership, e.g. which exact lines of code have been authored by which
developers, that is contained in the commit log of software projects.
Addressing this issue, we introduce git2net, a scalable python software that
facilitates the extraction of fine-grained co-editing networks in large git
repositories. It uses text mining techniques to analyse the detailed history of
textual modifications within files. This information allows us to construct
directed, weighted, and time-stamped networks, where a link signifies that one
developer has edited a block of source code originally written by another
developer. Our tool is applied in case studies of an Open Source and a
commercial software project. We argue that it opens up a massive new source of
high-resolution data on human collaboration patterns.Comment: MSR 2019, 12 pages, 10 figure
MoodBar: Increasing new user retention in Wikipedia through lightweight socialization
Socialization in online communities allows existing members to welcome and
recruit newcomers, introduce them to community norms and practices, and sustain
their early participation. However, socializing newcomers does not come for
free: in large communities, socialization can result in a significant workload
for mentors and is hard to scale. In this study we present results from an
experiment that measured the effect of a lightweight socialization tool on the
activity and retention of newly registered users attempting to edit for the
first time Wikipedia. Wikipedia is struggling with the retention of newcomers
and our results indicate that a mechanism to elicit lightweight feedback and to
provide early mentoring to newcomers improves their chances of becoming
long-term contributors.Comment: 9 pages, 5 figures, accepted for presentation at CSCW'1
Design of a shared whiteboard component for multimedia conferencing
This paper reports on the development of a framework for multimedia applications in the domain of tele-education. The paper focuses on the protocol design of a specific component of the framework, namely a shared whiteboard application. The relationship of this component with other components of the framework is also discussed. A salient feature of the framework is that it uses an advanced ATM-based network service. The design of the shared whiteboard component is considered representative for the design as a whole, and is used to illustrate how a flexible protocol architecture utilizing innovative network functions and satisfying demanding user requirements can be developed
SWISH: SWI-Prolog for Sharing
Recently, we see a new type of interfaces for programmers based on web
technology. For example, JSFiddle, IPython Notebook and R-studio. Web
technology enables cloud-based solutions, embedding in tutorial web pages,
atractive rendering of results, web-scale cooperative development, etc. This
article describes SWISH, a web front-end for Prolog. A public website exposes
SWI-Prolog using SWISH, which is used to run small Prolog programs for
demonstration, experimentation and education. We connected SWISH to the
ClioPatria semantic web toolkit, where it allows for collaborative development
of programs and queries related to a dataset as well as performing maintenance
tasks on the running server and we embedded SWISH in the Learn Prolog Now!
online Prolog book.Comment: International Workshop on User-Oriented Logic Programming (IULP
2015), co-located with the 31st International Conference on Logic Programming
(ICLP 2015), Proceedings of the International Workshop on User-Oriented Logic
Programming (IULP 2015), Editors: Stefan Ellmauthaler and Claudia Schulz,
pages 99-113, August 201
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