The interrelations between audio compression and graphical texture detail in video games : How they affect players perception of quality

Abstract: For this study three questions are being studied. Question one: “How does the audio compressionaffect the perceived video quality?” Question two is somewhat reversed: “How does the texturedetail affect the perceived audio quality?” The final question follows: “How do the audiocompression and texture detail affect the perceived overall quality?” The experiment was done on 36different untrained listeners, whereof 2 didn’t give complete answers and were therefore notincluded in the results. In total the result was based on 34 test subjects. Subjects participating in theexperiment had to play through three levels, one level for each research question. In each levelsubjects evaluated the game’s different qualities. In one level only the texture detail changed (LevelVV), in the other only audio compression rate changed (Level AA) and in the third both audiocompression and texture detail changed (Level AV). The texture detail ranged from low to medium tohigh setting, while the audio compression had four different levels ranging from 49 kbit/s to 150kbit/s, in the compressed format of ogg vorbis. The result shows that subjects did not perceive animprovement in quality in either of the single quality tests, i.e. levels AA and VV. In the last level withmultiple changing stimuli (AV), subjects could identify the lower video quality from medium and high.Subjects also showed a significant difference in perceived overall quality in the AV level, subjectsshowed that they could identify a difference in audio quality better, when video quality was on thelow setting.