Subjective evaluation of Head-Related Transfer Functions reconstructed with Spatial Principal Component Analysis and their domain dependency
* Presenting author
It is well known that data amount for spatial variation of Head-Related Transfer Functions (HRTFs) can be compressed by using Principal Component Analysis (PCA) with less perceptual influence. The PCA of the HRTFs is called Spatial PCA (SPCA). The author analyzed the effect of domain selection for SPCA in objective aspect [S. Takane, Appl. Acoust., 101, 64-77(2016)], but the effect is not analyzed in subjective aspect. In this paper, the effect was investigated using non-individual HRTFs with a 3 alternative forced choice (3AFC) experiment. The domains for the SPCA were HRIR (Head-Related Impulse Response), HRTF, amplitude of HRTF, and log-amplitude of HRTF. In the latter two domains, minimum phase was assumed for generating the phase components of the HRTFs reconstructed from the SPCA results. As a result, it was found that number of the principal components required to reconstruct the HRTFs with perceptually undetectable difference is small for all domains, and this corresponds to the results of many researches. Moreover, the HRTFs reconstructed from the results of the SPCA in log-amplitude domain achieved the relatively low number of the principal components, differed from the results of the objective evaluation done by the authors previous research.