1. DT_200906_VQEGMM2_AVtest.ppt1 Audio-visual quality tests. VQEG meeting, June 2009, Berlin Marie-Neige Garcia, Alexander Raake

2. DT_200906_VQEGMM2_AVtest.ppt2 Tests overview.  Scope: Audio-visual quality modeling for IPTV services  4 audio-visual tests:  2 HD  2 SD

3. DT_200906_VQEGMM2_AVtest.ppt3 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

4. DT_200906_VQEGMM2_AVtest.ppt4 Test design. Adressed degradations Audio degradationsVideo degradations TypeStrength Type Compression  High  Medium  Low  High  Medium  Low Compression Packet Loss  High  Medium  Low  High  Medium  Low Packet loss PLC: slicing  High  Medium  Low Packet loss PLC: freezing Combination of all degradation types at all degradation strengths

5. DT_200906_VQEGMM2_AVtest.ppt5 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

6. DT_200906_VQEGMM2_AVtest.ppt6 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

7. DT_200906_VQEGMM2_AVtest.ppt7 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