1,681 research outputs found
Influence of distortions of key frames on video transfer in wireless networks
In this paper it is shown that for substantial increase of video quality in
wireless network it is necessary to execute two obligatory points on
modernization of the communication scheme. The player on the received part
should throw back automatically duplicated RTP packets, server of streaming
video should duplicate the packets containing the information of key frames.
Coefficients of the mathematical model describing video quality in wireless
network have been found for WiFi and 3G standards and codecs MPEG-2 and MPEG-4
(DivX). The special experimental technique which has allowed collecting and
processing the data has been developed for calculation of values of factors.Comment: 6 pages, 4 figures, 2 Table
Modeling, Simulation and Analysis of Video Streaming Errors in Wireless Wideband Access Networks
Analysis of simulated models has become a veritable tool for
investigating network behavioral patterns vis-à-vis transmitted content. The
streaming video research domain employs modeling extensively due to availability
of relevant tools. A vast majority of which are presented on the FOSS platform.
The transmission of audio and video streaming services over different media is
becoming ever more popular. This widespread increase is accompanied by the
difficult task of maintaining the QoS of streaming video. The use of very accurate
coding techniques for transmissions over wireless networks alone cannot guarantee
a complete eradication of distortions characteristic of the video signal. A software-
hardware composite system has been developed for investigating the effect of
single bit error and bit packet errors in wideband wireless access systems on the
quality of H.264/AVC standard video streams. Numerical results of the modeling
and analysis of the effect of interference robustness on quality of video streaming
are presented and discussed. Analytic results also suggest that the Markov model
of packetization of error obtained from a real network for streaming video can be
used in the simulations of transmission of video across networks in the hardware-
software complex developed by the authors in a previous work
Effect of Wideband Wireless Access Systems Interference Robustness on the Quality of Video Streaming
The transmission of audio and video streaming
services over different conduits (wireless access systems,
Internet, etc.) is becoming ever more popular. This widespread
increase is accompanied by the attendant new and difficult task
of maintaining the quality of service of streaming video. The use of very accurate coding techniques for transmissions over wireless networks alone cannot guarantee a complete eradication of distortions characteristic of the video signal. A software-hardware composite system has been developed for investigating the effect of single bit error and bit packet errors in wideband wireless access systems on the quality of H.264/AVC standard bursty video streams. Numerical results of the modeling and analysis of the effect of interference robustness on quality of video streaming are presented and discussed
A reduced-reference perceptual image and video quality metric based on edge preservation
In image and video compression and transmission, it is important to rely on an objective image/video quality metric which accurately represents the subjective quality of processed images and video sequences. In some scenarios, it is also important to evaluate the quality of the received video sequence with minimal reference to the transmitted one. For instance, for quality improvement of video transmission through closed-loop optimisation, the video quality measure can be evaluated at the receiver and provided as feedback information to the system controller. The original image/video sequence-prior to compression and transmission-is not usually available at the receiver side, and it is important to rely at the receiver side on an objective video quality metric that does not need reference or needs minimal reference to the original video sequence. The observation that the human eye is very sensitive to edge and contour information of an image underpins the proposal of our reduced reference (RR) quality metric, which compares edge information between the distorted and the original image. Results highlight that the metric correlates well with subjective observations, also in comparison with commonly used full-reference metrics and with a state-of-the-art RR metric. © 2012 Martini et al
Generative Compression
Traditional image and video compression algorithms rely on hand-crafted
encoder/decoder pairs (codecs) that lack adaptability and are agnostic to the
data being compressed. Here we describe the concept of generative compression,
the compression of data using generative models, and suggest that it is a
direction worth pursuing to produce more accurate and visually pleasing
reconstructions at much deeper compression levels for both image and video
data. We also demonstrate that generative compression is orders-of-magnitude
more resilient to bit error rates (e.g. from noisy wireless channels) than
traditional variable-length coding schemes
Recommended from our members
Intelligent synthesis mechanism for deriving streaming priorities of multimedia content
We address the problem of integrating user preferences with network Quality of Service parameters for the streaming of media content, and suggest protocol stack configurations
that satisfy user and technical requirements to the best available degree. Our approach is able to handle inconsistencies between user and networking considerations, formulating the
problem of construction of tailor-made protocols as a prioritization problem, solvable using fuzzy programming
DVB-T Digital Terrestrial Television Transmission over Fading Channels
The paper deals with the transmission of the digital television signal according to the DVB-T standard in SFN network over fading channels for the fixed reception. The laboratory transmission system for the real broadcasting based on R&S RF test and measuring equipments is presented including the transmission parameters setup. The results of broadcasting over Gausian, Ricean and Rayleigh channels and results of the echo impairments are presented and discussed with the theory and simulation results. The BER before and after Viterbi decoding and according to MER equal to S/N ratio in the channel from the constellation diagram were compared in all transmission experiments. Additional picture quality evaluation is presented using DVQL-W metric that monitors blockiness structures in MPEG-2 compressed pictures and gives notice of known \"cliff-off\" effect
- …