Wagner R F, Brown D G, Pastel M S
Med Phys. 1979 Mar-Apr;6(2):83-94. doi: 10.1118/1.594559.
The imaging process has two fundamental stages: detection and display. The detection stage can be quantified rigourously using Shannon's information theory. This requires the contrast scale (CS), modulation transfer function (MTF), and noise power spectrum [N(f)] to be combined into a signal-to-noise ratio (SNR). This results in two fundamental summary figures of merit: the density of noise equivalent quanta (NEQ) in the image and the information bandwidth integral (IBWI). These algorithm-independent measures are used to quantify the recording stage. The display stage is less well understood since it couples to an external observer. Several types of decision makers are treated. Examples are drawn from first and second generation CT, demonstrating that thye are nearly quantum limited for large signals, indicating how their algorithms are matched or mismatched to the geometry, and calculating the contrast-detail diagrams for those decision makers.
检测和显示。检测阶段可以使用香农信息论进行严格量化。这需要将对比度标度（CS）、调制传递函数（MTF）和噪声功率谱[N(f)]组合成信噪比（SNR）。这产生了两个基本的品质因数汇总指标：图像中噪声等效量子（NEQ）的密度和信息带宽积分（IBWI）。这些与算法无关的测量用于量化记录阶段。由于显示阶段与外部观察者相关联，所以对其了解较少。文中讨论了几种类型的决策者。示例取自第一代和第二代CT，表明对于大信号它们几乎受量子限制，指出了它们的算法与几何结构如何匹配或不匹配，并为这些决策者计算了对比度细节图。
