Morrone M C, Burr D C
Department of Psychology, University of Western Australia, Nedlands.
Proc R Soc Lond B Biol Sci. 1988 Dec 22;235(1280):221-45. doi: 10.1098/rspb.1988.0073.
This paper presents a simple and biologically plausible model of how mammalian visual systems could detect and identify features in an image. We suggest that the points in a waveform that have unique perceptual significance as 'lines' and 'edges' are the points where the Fourier components of the waveform come into phase with each other. At these points 'local energy' is maximal. Local energy is defined as the square root of the sum of the squared response of sets of matched filters, of identical amplitude spectrum but differing in phase spectrum by 90 degrees: one filter type has an even-symmetric line-spread function, the other an odd-symmetric line-spread function. For a line the main contribution to the local energy peak is in the output of the even-symmetric filters, whereas for edges it is in the output of the odd-symmetric filters. If both filter types respond at the peak of local energy, both edges and lines are seen, either simultaneously or alternating in time. The model was tested with a series of images, and shown to predict well the position of perceived features and the organization of the images.
本文提出了一个简单且符合生物学原理的模型，用于解释哺乳动物视觉系统如何检测和识别图像中的特征。我们认为，波形中具有独特感知意义的“线条”和“边缘”的点，是波形的傅里叶分量相互同相的点。在这些点上，“局部能量”最大。局部能量定义为一组匹配滤波器平方响应之和的平方根，这些滤波器具有相同的幅度谱，但相位谱相差90度：一种滤波器类型具有偶对称线扩展函数，另一种具有奇对称线扩展函数。对于线条，局部能量峰值的主要贡献来自偶对称滤波器的输出，而对于边缘，则来自奇对称滤波器的输出。如果两种滤波器类型都在局部能量峰值处响应，则会同时或交替看到边缘和线条。该模型用一系列图像进行了测试，并被证明能够很好地预测感知特征的位置和图像的组织。
