Speaker: Bo Zhong & Ammar Lilamwala

Title: Perceptual Quality and Quality of Experience


This presentation is based on the tutorial “From Qos through to QoE” at QEST 2012. In this presentation we will talk about Quality of Experience (QoE), the importance of using QoE to measure end-user satisfaction, the methods available to measure QoE, the pros and cons of the methodologies available. We will then talk about Pseudo Subject Quality Assessment (PSQA) methodology proposed by the author of the tutorial. We will conclude by talking about how we use QoE in our research.

“QoE is a measure of the overall performance of a system as perceived subjectively by an end-user”. The popularity of an application is directly related to the end-user’s satisfaction, which is a component of QoE. Therefore methodologies to quantify QoE are needed. Subjective and Objective methodologies are available to measure the “Perceptual Quality” (PQ) of an application and either of the method has its pros and cons. The need to measure quality in real time along with time savings and cheapness in comparison to subjective methodologies is what makes objective methodologies the preferred way to measure PQ. To address the cons of the objective method, a hybrid of the subjective and objective methodologies known as Pseudo Subjective Quality Assessment (PSQA) is proposed by the authors of the tutorial.

PSQA consists of training a Random Neural Network to behave as a human observer and to deliver a numerical evaluation of quality, which must be close to the average value set of human observers would give to the received service streams. PSQA allows to reach the objective of being able to measure quality as perceived by the users, automatically and accurately. The implementation of PSQA involves several steps including subjective tests and learning. Case study result shows that PSQA is able to provide accurate prediction of subjective perception, and can be applied to control end to end transmission in order to achieve better user experiences.

Throughout the presentation, the authors made a clear distinction between perceptual quality and QoE, however, they conclude by stating PQ and QoE are used interchangeably and therefore the methods available for PQ are equally applicable to measure QoE.

Date: 7th  November, 2012.

Time: 14.00-15.00 hrs

Venue:  QMUL Maths:1.03

2012 Nov 7- Bo Zhong & Ammar Lilamwala