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Audio-visual quality tests. VQEG meeting, June 2009, Berlin. Marie-Neige Garcia, Alexander Raake. Tests overview. Scope: Audio-visual quality modeling for IPTV services 4 audio-visual tests: 2 HD 2 SD. Modeling approach*. Quality-based*: Audio quality – video quality interaction:
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Audio-visual quality tests.VQEG meeting, June 2009, Berlin Marie-Neige Garcia, Alexander Raake DT_200906_VQEGMM2_AVtest.ppt
Tests overview. • Scope: Audio-visual quality modeling for IPTV services • 4 audio-visual tests: • 2 HD • 2 SD DT_200906_VQEGMM2_AVtest.ppt
Modeling approach*. • Quality-based*: Audio quality – video quality interaction: => Impact of degradation type? => Impact of content? • Impairment-factor based*: * Garcia, M.N, Raake, A. „Impairment-factor-based audio-visual quality model for IPTV”, to be published in Qomex 2009, San Diego DT_200906_VQEGMM2_AVtest.ppt
Test design.Adressed degradations Combination of all degradation types at all degradation strengths DT_200906_VQEGMM2_AVtest.ppt
Test design.Audio-visual stimuli • 5 audio-visual contents • Duration: 16s • Video format: SD, HD • Audio format: 48 Hz, 16 bit, stereo, normalized. • Types of degradations: • Audio and video coding impairments • Audio and video transmission impairment (video: slicing & freezing) • 49 HRCs, 245 PVS => 3 test sessions per format => use of anchors: 9 common HRCs (45 PVS) in each session DT_200906_VQEGMM2_AVtest.ppt
Test design.Test method • Test method: ACR • Rating scale: 11-point continuous scale • Question asked: please rate the overall quality (image + sound) • 1 subject per session • 24 subjects per test DT_200906_VQEGMM2_AVtest.ppt
Test design.Test equipment • LCD screen (Barco 1080p 42“) • 2 Genelec 8030.LSE stereo loudspeakers • Audio calibration: • on pink noise (-18dB) • Listening level: • SPL A-weighted(A-WTD) Leq slow mode • ~65dB (62dB for each loudspeakers) • Low background room illumination (<20 lux) • No background noise DT_200906_VQEGMM2_AVtest.ppt