scholarly journals A Lossless Video Compression Method Based on Adaptive Linear Predictive Coding Using Spatio-temporal Hilbert Scanning.

Author(s):  
Yukihiro Bando ◽  
Takamasa Yokoyama ◽  
Sei-ichiro Kamata
Author(s):  
Martin Fleury ◽  
Ismail Ali ◽  
Nadia Qadri ◽  
Mohammed Ghanbari

Mobile devices are replacing the desktop computer in most spheres outside the workplace. This development brings a problem to video streaming services, as wireless channels are fundamentally error-prone, whereas video compression depends for most of its gains on predictive coding. The H.264 codec family has included a good number of error resilience facilities to counter-act the spatio-temporal error propagation brought on by packet loss. This chapter outlines these facilities before examining ways in which predictive coding can be temporally restrained. In particular, intra-refresh techniques are the focus, as these bring additional utility to the video stream. For example, the chapter compares periodic and gradual intra-refresh, each of which provides recovery points for the decoder and also allow stream switching or joining at these points. Thus, in intra-coding, the more normal temporal prediction is temporally replaced by spatial prediction, at a cost in coding efficiency but allowing a decoder in a mobile device to reset itself. After a review of research into this area, the chapter provides a case study in non-periodic intra-refresh before considering possible future research directions.


2020 ◽  
Vol 6 (s1) ◽  
Author(s):  
Tyler Kendall ◽  
Charlotte Vaughn

AbstractThis paper contributes insight into the sources of variability in vowel formant estimation, a major analytic activity in sociophonetics, by reviewing the outcomes of two simulations that manipulated the settings used for linear predictive coding (LPC)-based vowel formant estimation. Simulation 1 explores the range of frequency differences obtained when minor adjustments are made to LPC settings, and measurement timepoints around the settings used by trained analysts, in order to determine the range of variability that should be expected in sociophonetic vowel studies. Simulation 2 examines the variability that emerges when LPC settings are varied combinatorially around constant default settings, rather than settings set by trained analysts. The impacts of different LPC settings are discussed as a way of demonstrating the inherent properties of LPC-based formant estimation. This work suggests that differences more fine-grained than about 10 Hz in F1 and 15–20 Hz in F2 are within the range of LPC-based formant estimation variability.


2017 ◽  
Vol 24 (2) ◽  
pp. 17-26
Author(s):  
Mustafa Yagimli ◽  
Huseyin Kursat Tezer

Abstract The real-time voice command recognition system used for this study, aims to increase the situational awareness, therefore the safety of navigation, related especially to the close manoeuvres of warships, and the courses of commercial vessels in narrow waters. The developed system, the safety of navigation that has become especially important in precision manoeuvres, has become controllable with voice command recognition-based software. The system was observed to work with 90.6% accuracy using Mel Frequency Cepstral Coefficients (MFCC) and Dynamic Time Warping (DTW) parameters and with 85.5% accuracy using Linear Predictive Coding (LPC) and DTW parameters.


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