Sarkar Abhijit, Autrusseau Florent, Viénot Françoise, Le Callet Patrick, Blondé Laurent
Technicolor Research & Innovation, Cesson-Sévigné, France.
J Opt Soc Am A Opt Image Sci Vis. 2011 Oct 1;28(10):2033-48. doi: 10.1364/JOSAA.28.002033.
In the context of color perception on modern wide-gamut displays with narrowband spectral primaries, we performed a theoretical analysis on various aspects of physiological observers proposed by CIE TC 1-36 (CIEPO06). We allowed certain physiological factors to vary, which was not considered in the CIEPO06 framework. For example, we analyzed that the long-wave-sensitive (LWS) or medium-wave-sensitive (MWS) peak wavelength shift in the photopigment absorption spectra, a factor not modeled in CIEPO06, contributed more toward observer variability than some of the factors considered in the model. Further, we compared the color-matching functions derived from the CIEPO06 model and the CIE 10° standard colorimetric observer to the average observer data from three distinct subgroups of Stiles-Burch observers, formed on the basis of observer ages (22-23 years, 27-29 years, and 49-50 years). The errors in predicting the x(λ) and y(λ) color-matching functions of the intragroup average observers in the long-wave range and in the medium-wave range, respectively, were generally more in the case of the CIEPO06 model compared to the 10° standard colorimetric observer and manifested in both spectral and chromaticity space. In contrast, the short-wave-sensitive z₁₀(λ) function of the 10° standard colorimetric observer performed poorly compared to the CIEPO06 model for all three subgroups. Finally, a constrained nonlinear optimization on the CIEPO06 model outputs showed that a peak wavelength shift of photopigment density alone could not improve the model prediction errors at higher wavelengths. As an alternative, two optimized weighting functions for each of the LWS and MWS cone photopigment densities led to significant improvement in the prediction of intra-age-group average data for both the 22-23 year and 49-50 year age groups. We hypothesize that the assumption in the CIEPO06 model that the peak optical density of visual pigments does not vary with age is false and is the source of these prediction errors at higher wavelengths. Correcting these errors in the model can lead to an improved age-dependent observer and can also help update the current CIE 10° standard colorimetric observer. Accordingly, it would reduce the discrepancies between color matches with broadband spectral primaries and color matches with narrowband spectral primaries.
在现代具有窄带光谱原色的广色域显示器的颜色感知背景下，我们对国际照明委员会（CIE）第1 - 36技术委员会（CIEPO06）提出的生理观察者的各个方面进行了理论分析。我们允许某些生理因素变化，而这些因素在CIEPO06框架中未被考虑。例如，我们分析了视色素吸收光谱中的长波敏感（LWS）或中波敏感（MWS）峰值波长偏移，这是CIEPO06模型中未建模的一个因素，它对视观察者变异性的贡献比模型中考虑的一些因素更大。此外，我们将从CIEPO06模型和CIE 10°标准色度观察者得出的颜色匹配函数与基于观察者年龄（22 - 23岁、27 - 29岁和49 - 50岁）形成的三个不同子组的Stiles - Burch观察者的平均观察者数据进行了比较。与10°标准色度观察者相比，CIEPO06模型在预测组内平均观察者在长波范围和中波范围内的x(λ)和y(λ)颜色匹配函数时的误差通常更大，并且在光谱和色度空间中都有体现。相比之下，对于所有三个子组，10°标准色度观察者的短波敏感z₁₀(λ)函数与CIEPO06模型相比表现较差。最后，对CIEPO06模型输出进行的约束非线性优化表明，仅视色素密度的峰值波长偏移并不能改善较高波长处的模型预测误差。作为一种替代方法，针对LWS和MWS锥体视色素密度分别采用两个优化加权函数，在预测22 - 23岁和49 - 50岁年龄组的年龄组内平均数据时带来了显著改进。我们假设CIEPO06模型中视觉色素的峰值光密度不随年龄变化这一假设是错误的，并且是这些较高波长处预测误差的来源。纠正模型中的这些误差可以得到改进的年龄相关观察者，也有助于更新当前的CIE 10°标准色度观察者。因此，这将减少宽带光谱原色的颜色匹配与窄带光谱原色的颜色匹配之间的差异。
