Dimitris Agrafiotis
Department of Electrical and Electronic Engineering, University of Bristol

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Reduced-reference Video Quality Metric Using Spatio-temporal Activity Information Farah Diyana Abdul Rahman; Ahmad Imran Ibrahim; Dimitris Agrafiotis
TELKOMNIKA (Telecommunication Computing Electronics and Control) Vol 16, No 2: April 2018
Publisher : Universitas Ahmad Dahlan

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.12928/telkomnika.v16i2.9044

Abstract

Monitoring and maintaining acceptable Quality of Experience is of great importance to video service providers.  Perceived visual quality of transmitted video via wireless networks can be degraded by transmission errors. This paper presents a reduced-reference video quality metric of very low complexity and overhead that makes use of frame based spatial (SI) and temporal (TI) activity levels to monitor the effect of channel errors on video transmitted over error prone networks. The performance of the metric is evaluated relative to that of a number of full and reduced reference metrics. The proposed metric outperforms some of the most popular full reference metrics whilst requiring very little overhead.
Edge Dissimilarity Reduced-Reference Quality Metric with Low Overhead Bitrate Farah Diyana Abdul Rahman; Dimitris Agrafiotis; Ahmad Imran Ibrahim
Indonesian Journal of Electrical Engineering and Computer Science Vol 10, No 2: May 2018
Publisher : Institute of Advanced Engineering and Science

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.11591/ijeecs.v10.i2.pp631-640

Abstract

In multimedia transmission, it is important to rely on an objective quality metric which accurately represents the subjective quality of processed images and video sequences. Reduced-reference metrics make use of side-information that is transmitted to the receiver for estimating the quality of the received sequence with low complexity. In this paper, an Edge-based Dissimilarity Reduced-Reference video quality metric with low overhead bitrate is proposed. The metric is evaluated by finding the dissimilarity between the edge information of original and distorted sequences. The edge degradation can be detected in this manner as perceived video quality is highly associated with edge structural. Due to the high overhead using the Soergel distance, it is pertinent to find a way to reduce the overhead while maintaining the edge information that can convey the quality measure of the sequences. The effects of different edge detection operator, video resolution and file compressor are investigated. The aim of this paper is to significantly reduce the bitrate required in order to transmit the side information overhead as the reduced reference video quality metric. From the results obtained, the side information extracted using Sobel edge detector maintained consistency throughout the reduction of spatial and temporal down-sample.