Experienced quality factors: qualitative evaluation approach to audiovisual quality

Abstract

Subjective evaluation is used to identify impairment factors of multimedia quality. The final quality is often formulated via quantitative experiments, but this approach has its constraints, as subject's quality interpretations, experiences and quality evaluation criteria are disregarded. To identify these quality evaluation factors, this study examined qualitatively the criteria participants used to evaluate audiovisual video quality. A semi-structured interview was conducted with 60 participants after a subjective audiovisual quality evaluation experiment. The assessment compared several, relatively low audio-video bitrate ratios with five different television contents on mobile device. In the analysis, methodological triangulation (grounded theory, Bayesian networks and correspondence analysis) was applied to approach the qualitative quality. The results showed that the most important evaluation criteria were the factors of visual quality, contents, factors of audio quality, usefulness -followability and audiovisual interaction. Several relations between the quality factors and the similarities between the contents were identified. As a research methodological recommendation, the focus on content and usage related factors need to be further examined to improve the quality evaluation experiments.

User Perception of Media Content Association in Olfaction-Enhanced Multimedia

“…The results from the repeated measures ANOVA test show that the effects of the two factors under consideration, as well as the interaction effects between them are statistically significant. Thus, as previous research (Ghinea and Thomas, 1998;Jumisko-Pyykkö et al, 2007) and the results from the earlier experiments reported in this research work have shown (Ghinea and Ademoye 2010; Ghinea and Ademoye, in press) content has a significant impact on users' perception of multimedia (F=3.989, p=0.002). More importantly, however, the association between olfactory media content and audiovisual content in the olfaction-enhanced videos was also found to be significant, and consequently impacts on the perceived sense of relevance of the olfactory media (F=42.965, p=0.000).…”

A Qualitative Approach to Evaluation of Perceived Qualities of Audio and Video in a Distance Education Context

“…This approach also allows more flexibility in data collection because follow-up questions can be asked [32], which is not possible with questionnaires. Collecting descriptive data from interviews could be beneficial when the research field is relatively unexplored [20].…”

“…Jumisko-Pyykkö et al [20] used aqualitative approach to evaluate audio-visual quality by combining asingle-stimulus method, for quality evaluation, with semi-structured interviews, to establish quality evaluation criteria. The data analysis combined aq ualitative analysis based on grounded theory and aq uantitative statistical analysis, Bayesian modelling.…”

“…Other researchers have already applied grounded theory in the form of semi-structured interviews to evaluate the perception of audio-visual quality [20,21] (asd iscussed Table I. Top: Questionnaire 1.…”

Understanding User Experience of Mobile Video: Framework, Measurement, and Optimization

“…Given a bit rate constraint, the video can be encoded with different parameters by different video coding codecs; and the variations eventually lead to divergent user-perceived video qualities (Ahmad, 2006b;Cranley, Murphy & Perry, 2004;Kun, Richard & Shih-Ping, 2001;Song, Tjondronegoro & Azad, 2010). Audio quality, including the volume, sampling rate, bit rate of the audio, often takes effects with the usage ambient (e.g., noisy or quiet) and the content type (e.g., music videos) together (JumiskoPyykkö, Häkkinen & Nyman, 2007). Delivery strategy is about how the video service is delivered to the user.…”