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Illusory Contours and Linear Neurons

B. Skottun
Journal / Anthology

Experimental Brain Research
Year: 1994
Volume: 100
Page range: 360-364

The purpose of the project described here is to provide a graphic demonstration of the role of phases and amplitudes in determining the appearance of printed characters. The images of two printed characters are Fourier analyzed and the amplitude spectrum of one is combined with the phase spectrum of the other. In the resulting hybrid image, one can clearly recognize the letter whose phase spectrum is used, while no trace of the other letter is evident. This procedure is also carried out with letters of different fonts and sizes. Again, the resulting images are mainly determined by the phase spectra. However, with letter of different sizes, the amplitude spectra, as one might expect, influence the appearance.

*Science > Biology