Error-resilient performance of Dirac video codec over packet-erasure channel

Video transmission over the wireless or wired network requires error-resilient mechanism since compressed video bitstreams are sensitive to transmission errors because of the use of predictive coding and variable length coding. This paper investigates the performance of a simple and low complexity error-resilient coding scheme which combines source and channel coding to protect compressed bitstream of wavelet-based Dirac video codec in the packet-erasure channel. By partitioning the wavelet transform coefficients of the motion-compensated residual frame into groups and independently processing each group using arithmetic and Forward Error Correction (FEC) coding, Dirac could achieves the robustness to transmission errors by giving the video quality which is gracefully decreasing over a range of packet loss rates up to 30% when compared with conventional FEC only methods. Simulation results also show that the proposed scheme using multiple partitions can achieve up to 10 dB PSNR gain over its existing un-partitioned format. This paper also investigates the error-resilient performance of the proposed scheme in comparison with H.264 over packet-erasure channel

Enabling error-resilient internet broadcasting using motion compensated spatial partitioning and packet FEC for the dirac video codec

Video transmission over the wireless or wired network require protection from channel errors since compressed video bitstreams are very sensitive to transmission errors because of the use of predictive coding and variable length coding. In this paper, a simple, low complexity and patent free error-resilient coding is proposed. It is based upon the idea of using spatial partitioning on the motion compensated residual frame without employing the transform coefficient coding. The proposed scheme is intended for open source Dirac video codec in order to enable the codec to be used for Internet broadcasting. By partitioning the wavelet transform coefficients of the motion compensated residual frame into groups and independently processing each group using arithmetic coding and Forward Error Correction (FEC), robustness to transmission errors over the packet erasure wired network could be achieved. Using the Rate Compatibles Punctured Code (RCPC) and Turbo Code (TC) as the FEC, the proposed technique provides gracefully decreasing perceptual quality over packet loss rates up to 30%. The PSNR performance is much better when compared with the conventional data partitioning only methods. Simulation results show that the use of multiple partitioning of wavelet coefficient in Dirac can achieve up to 8 dB PSNR gain over its existing un-partitioned method

Abdominopelvic Splenosis—An Unusual Cause of Tenesmus

Splenosis is a rare condition defined as seeding and autotransplantation of splenic tissue, typically after blunt abdominal trauma (e.g. from road traffic collision). Sites of splenosis ranging from intrathoracic to intrapelvic have been reported, and symptoms vary greatly depending on the site and size of lesions. We present the use of Tc-99m sulphur colloid SPECT/CT in diagnosing a case of multiple abdominopelvic splenosis as the cause of new-onset tenesmus and constipation, which was initially thought to be due to colorectal malignancy, 47 years following the initial abdominal trauma

Computational depth of anesthesia via multiple vital signs based on artificial neural networks

This study evaluated the depth of anesthesia (DoA) index using artificial neural networks (ANN) which is performed as the modeling technique. Totally 63-patient data is addressed, for both modeling and testing of 17 and 46 patients, respectively. The empirical mode decomposition (EMD) is utilized to purify between the electroencephalography (EEG) signal and the noise. The filtered EEG signal is subsequently extracted to achieve a sample entropy index by every 5-second signal. Then, it is combined with other mean values of vital signs, that is, electromyography (EMG), heart rate (HR), pulse, systolic blood pressure (SBP), diastolic blood pressure (DBP), and signal quality index (SQI) to evaluate the DoA index as the input. The 5 doctor scores are averaged to obtain an output index. The mean absolute error (MAE) is utilized as the performance evaluation. 10-fold cross-validation is performed in order to generalize the model. The ANN model is compared with the bispectral index (BIS). The results show that the ANN is able to produce lower MAE than BIS. For the correlation coefficient, ANN also has higher value than BIS tested on the 46-patient testing data. Sensitivity analysis and cross-validation method are applied in advance. The results state that EMG has the most effecting parameter, significantly.This research is financially supported by the Ministry of Science and Technology (MOST) of Taiwan. This research is also supported by the Centre for Dynamical Biomarkers and Translational Medicine, National Central University, Taiwan, which is also sponsored by MOST (MOST103-2911-I-008-001). Also, it is supported by National Chung-Shan Institute of Science & Technology in Taiwan (Grant nos. CSIST-095-V301 and CSIST-095-V302)

Analysis of cyclic delay diversity on DVB-H systems over spatially correlated channel

The objective of this work is to research and analyze the performance of Cyclic Delay Diversity (CDD) with two transmit antenna on DVB-H systems operating in spatially correlated channel. It is shown in this paper that CDD can achieve desirable transmit diversity gain over uncorrelated channel with or without receiver diversity. However, in reality, the respective signal paths between spatially separated antennas and the mobile receiver is likely to be correlated because of insufficient antenna separation at the transmitter and the lack of scattering effect of the channel. Under this spatially correlated channel, it is apparent that CDD cannot achieve the same diversity gain as obtained under the uncorrelated channel. In this paper, a new upper bound on the pairwise error probability (PEP) of the CDD with spatial correlation of two transmit antennas is derived. The upper bound is used to study the CDD theoretical error performance and diversity gain losses over a generalized spatially correlated Rayleigh channel. This theoretical analysis is validated by the simulation of DVB-H systems with two transmit antennas and the CDD scheme. Both the theoretical and simulated results give the valuable insight that the CDD ability to perform well with a certain amount of channel correlation

Evaluation of diversity gains for DVB-T systems

Copyright @ 2008 Eurescom GmbHThe requirements for future DVB-T/H networks demand that broadcasters design and deploy networks that provide ubiquitous reception in challenging indoors and other obstructed situations. It is essential that such networks are designed costeffectively and with minimized environmental impact. The EC funded project PLUTO has since its start in 2006 explored the use of diversity to improve coverage in these difficult situations. The purpose of this paper is to investigate the performance of transmit and receive diversity gains with two antennas to improve the reception of DVB-T/H systems operating in different realistic propagation conditions through a series of tests using the Spirent dual channel emulator

Rooftop and indoor reception with transmit diversity applied to DVB-T networks: A long term measurement campaign

Although transmit Delay Diversity (DD) can provide a gain in indoor and other Non Line of Sight situations (NLOS), it can introduce degradation in rooftop reception. In fact, when the Ricean K factor of the channel is significantly high (e.g. Line of Sight reception), the channel performs similar to an AWGN channel where the performance degrades due to DD that artificially increase the fading. This paper investigates through practical evaluation the impacts of Transmit DD on LOS and NLOS stationary reception. Then, it studies 2 techniques to reduce the degradation performance in LOS while aiming to keep the same diversity gain in NLOS receptio

Analysis of DVB-H network coverage with the application of transmit diversity

This paper investigates the effects of the Cyclic Delay Diversity (CDD) transmit diversity scheme on DVB-H networks. Transmit diversity improves reception and Quality of Service (QoS) in areas of poor coverage such as sparsely populated or obscured locations. The technique not only povides robust reception in mobile environments thus improving QoS, but it also reduces network costs in terms of the transmit power, number of infrastructure elements, antenna height and the frequency reuse factor over indoor and outdoor environments. In this paper, the benefit and effectiveness of CDD transmit diversity is tackled through simulation results for comparison in several scenarios of coverage in DVB-H networks. The channel model used in the simulations is based on COST207 and a basic radio planning technique is used to illustrate the main principles developed in this paper. The work reported in this paper was supported by the European Commission IST project—PLUTO (Physical Layer DVB Transmission Optimization)

Estimating the economic burden of cardiovascular events in patients receiving lipid-modifying therapy in the UK.

OBJECTIVES: To characterise the costs to the UK National Health Service of cardiovascular (CV) events among individuals receiving lipid-modifying therapy. DESIGN: Retrospective cohort study using Clinical Practice Research Datalink records from 2006 to 2012 to identify individuals with their first and second CV-related hospitalisations (first event and second event cohorts). Within-person differences were used to estimate CV-related outcomes. SETTING: Patients in the UK who had their first CV event between January 2006 and March 2012. PARTICIPANTS: Patients ≥18 years who had a CV event and received at least 2 lipid-modifying therapy prescriptions within 180 days beforehand. PRIMARY AND SECONDARY OUTCOME MEASURES: Direct medical costs (2014 £) were estimated in 3 periods: baseline (pre-event), acute (6 months afterwards) and long-term (subsequent 30 months). Primary outcomes included incremental costs, resource usage and total costs per period. RESULTS: There were 24 093 patients in the first event cohort of whom 5274 were included in the second event cohort. The mean incremental acute CV event costs for the first event and second event cohorts were: coronary artery bypass graft/percutaneous transluminal coronary angioplasty (CABG/PTCA) £5635 and £5823, myocardial infarction £4275 and £4301, ischaemic stroke £3512 and £4572, heart failure £2444 and £3461, unstable angina £2179 and £2489 and transient ischaemic attack £1537 and £1814. The mean incremental long-term costs were: heart failure £848 and £2829, myocardial infarction £922 and £1385, ischaemic stroke £973 and £682, transient ischaemic attack £705 and £1692, unstable angina £328 and £677, and CABG/PTCA £-368 and £599. Hospitalisation accounted for 95% of acute and 61% of long-term incremental costs. Higher comorbidity was associated with higher long-term costs. CONCLUSIONS: Revascularisation and myocardial infarction were associated with the highest incremental costs following a CV event. On the basis of real-world data, the economic burden of CV events in the UK is substantial, particularly among those with greater comorbidity burden