Conference Paper

Explicit and Implicit Measures in Video Quality Assessment

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... Its main drawback is that it measures the subjective judgment of viewers and, hence, does not provide information about the processes that underlie the forming of the said judgment. To this end, physiological methods such as electroencephalogram (EEG) have been helpful [5]. ...
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The omnidirectional nature of Virtual Reality (VR) content provides an immersive experience for the viewer. At the same time, VR content relies heavily on the quality of the video to deliver an immersive experience. This study investigates the effect of video quality degradation on aspects of the viewer’s quality of experience (QoE) via subjective (i.e., a questionnaire) and objective (i.e., electroencephalogram) methods. We measured the viewer’s experience of watching a five-minute-long 6DoF VR movie in four video quality versions. Analysis of the questionnaire data showed that subjective ratings of the video quality decreased in parallel with the degradation of the quality. Also, the lower video quality versions yielded lower sensory immersion and simulator sickness scores. Finally, analysis of the EEG data revealed significantly lower parietal and occipital alpha values for the low video quality versions of the content.
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