MODEL OBSERVERS FOR ASSESSMENT OF IMAGE QUALITY
MODEL OBSERVERS FOR ASSESSMENT OF IMAGE QUALITY
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DOI：
10.1073/pnas.90.21.9758
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发表时间：
1993-11-01
影响因子：
11.1
通讯作者：
MYERS, KJ
中科院分区：
文献类型：
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作者：
BARRETT, HH;YAO, J;MYERS, KJ
图像质量可以根据某个“观察者”(无论是人还是数学模型)在一些实际感兴趣的任务中的表现来客观地定义。如果图像的最终用户将是人类，则使用模型观察者来预测通过心理物理研究测量的人类的任务表现，从而作为优化图像质量的基础。在本文中，我们考虑了噪声图像中弱信号的检测任务。所考虑的数学观测器包括理想贝叶斯观测器、非预白化匹配滤波器、基于线性判别分析的模型，称为霍特林观测器，以及修正的霍特林观测器和贝叶斯观测器，以解释人类视觉系统中的空间频率选择性通道。简要回顾了这些观察者模型背后的理论，并总结了与这些观察者模型之间的选择有关的几个心理物理学研究。在这里考虑的所有情况下，只有带有通道的霍特林模型在数学上是容易处理的，并且能够解释所有这些数据。该模型不需要调整参数来拟合数据，并且对通道机制的细节相对不敏感。因此，我们建议将其作为一种有用的模型观测器，用于评估和优化简单检测任务的图像质量。
Image quality can be defined objectively in terms of the performance of some ''observer'' (either a human or a mathematical model) for some task of practical interest. If the end user of the image will be a human, model observers are used to predict the task performance of the human, as measured by psychophysical studies, and hence to serve as the basis for optimization of image quality. In this paper, we consider the task of detection of a weak signal in a noisy image. The mathematical observers considered include the ideal Bayesian, the nonprewhitening matched filter, a model based on linear-discriminant analysis and referred to as the Hotelling observer, and the Hotelling and Bayesian observers modified to account for the spatial-frequency-selective channels in the human visual system. The theory behind these observer models is briefly reviewed, and several psychophysical studies relating to the choice among them are summarized. Only the Hotelling model with channels is mathematically tractable in all cases considered here and capable of accounting for all of these data. This model requires no adjustment of parameters to fit the data and is relatively insensitive to the details of the channel mechanism. We therefore suggest it as a useful model observer for the purpose of assessing and optimizing image quality with respect to simple detection tasks.