4. Audiovisual Integration for Call Quality

Multi-modal aspects of audiovisual quality assessment for interactive communication services are presented in this chapter. The focus is brought on how perceived auditory and visual qualities integrate to form an overall audiovisual quality perception for different experimental contexts. In particular, three main aspects are investigated: first, the influence of the experimental context referring to the mode of assessment (whether the subjects are placed in a one-way listening and viewing setting, or in a two-way interactive situation of assessment) on the audio, video and audiovisual qualities; second, the effects of cross-modal interactions on the assessment of the audio and video qualities are measured for those experimental contexts and confronted to the results found in the literature; third, the impact of the conversational scenario on the assessment of the auditory and visual qualities is investigated. Finally, audiovisual integration functions are proposed for each mode of assessment and conversational scenario that can be used in a general context.