Conference Paper

Influence of chroma variations on naturalness and image quality of stereoscopic images.

DOI: 10.1117/12.817749 Conference: Human Vision and Electronic Imaging XIV - part of the IS&T-SPIE Electronic Imaging Symposium, San Jose, CA, USA, January 19-22, 2009, Proceedings
Source: DBLP

ABSTRACT The computational view on image quality of Janssen and Blommaert states
that the quality of an image is determined by the degree to which the
image is both useful (discriminability) and natural (identifiability).
This theory is tested by creating two manipulations. Firstly,
multiplication of the chroma values of each pixel with a constant in the
CIELab color space, i.e., chroma manipulation, is expected to increase
only the usefulness by increasing the distances between the individual
color points, enhancing the contrast. Secondly, introducing stereoscopic
depth by varying the screen disparity, i.e., depth manipulation, is
expected to increase both the usefulness and the naturalness. Twenty
participants assessed perceived image quality, perceived naturalness and
perceived depth of the manipulated versions of two natural scenes. The
results revealed a small, yet significant shift between image quality
and naturalness as a function of the chroma manipulation. In line with
previous research, preference in quality was shifted to higher chroma
values in comparison to preference in naturalness. Introducing depth
enhanced the naturalness scores, however, in contrast to our
expectations, not the image quality scores. It is argued that image
quality is not sufficient to evaluate the full experience of 3D. Image
quality appears to be only one of the attributes underlying the
naturalness of stereoscopic images.

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