The performance of the MaxRGB illumination-estimation method for color constancy and automatic white balancing has been reported in the literature as being mediocre at best; however, MaxRGB has usually been tested on images of only 8-bits per channel. The question arises as to whether the method itself is inadequate, or rather whether it has simply been tested on data of inadequate dynamic range. To address this question, a database of sets of exposurebracketed images was created. The image sets include exposures ranging from very underexposed to slightly overexposed. The color of the scene illumination was determined by taking an extra image of the scene containing 4 Gretag Macbeth mini Colorcheckers placed at an angle to one another. MaxRGB was then run on the images of increasing exposure. The results clearly show that its performance drops dramatically when the 14-bit exposure range of the Nikon D700 camera is exceeded, thereby resulting in clipping of high values. For those images exposed such that no clipping occurs, the median error in MaxRGB's estimate of the color of the scene illumination is found to be relatively small.
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机译：在文献中报道了MAXRGB照明估计方法的性能和自动白色平衡的估计方法是最佳平庸;但是，MaxRGB通常在每个通道仅8位的图像上进行测试。问题出现了该方法本身是否不充分，或者是在动态范围不足的数据上是否已经测试过。为了解决这个问题，创建了一组曝光映像数据库。图像集包括从非常曝光的曝光范围到略微过度曝光的曝光。通过拍摄彼此以一定角度放置的4个Gretag Macbeth Mini Colorcheckers的场景的额外图像来确定场景照明的颜色。然后在MaxRGB上运行越来越多的曝光的图像。结果清楚地表明，当超过尼康D700摄像机的14位曝光范围时，其性能显着下降，从而导致高值的剪切。对于暴露的那些图像，使得不会发生剪裁，MaxRGB在场景照明颜色的估计中的中值误差被发现相对较小。
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