通过彩色数码相机单幅RGB图像的响应值重建物体表面的光谱反射率,不仅可以有效避免基于带通滤光片光谱成像系统存在的通道间图像像素偏移问题,而且可以缩短图像采集周期和获得高空间分辨率的光谱图像,但是光谱重建误差受光谱重建方法的影响。提出了一种基于相机响应值扩展和局部反距离加权优化的光谱重建方法,以CIEDE2000色差和光谱均方根误差为评价指标,以600个矿物颜料色块为实验样本,利用佳能600D型数码相机对所提方法进行了验证,并与当前几种较先进的方法进行了对比。实验结果表明,所提方法的平均CIEDE2000色差和平均光谱均方根误差分别降低到1.0389和0.0230,所提方法的光谱重建精度优于当前几种较先进方法的光谱重建精度。

Spectral reflectance reconstruction from a single RGB image of a trichromatic digital camera not only can effectively avoid the pixel distortion between the imaging channels existing in spectrum imaging system based on optical bandpass filters, but also can save the capturing time and acquire the spectral images with high spatial resolution. However, the spectral reconstruction error is influenced by reconstruction methods. A new spectral reconstruction method based on camera response expansion and local inverse distance weighted optimization is proposed. Using CIEDE2000 color difference and spectral root-mean-square error as the evaluated metrics, we use Canon 600D digital camera to verify the proposed method, and compare the proposed method with current advanced methods. The results show that the proposed method outperforms the several existing advanced methods, and average CIEDE2000 color difference and average spectral root-mean-square error of the proposed method decrease to 1.0389 and 0.0230, respectively.