Recognition of positive and negative bandpass-filtered images.
A study is reported in which the significance for vision of low- and high-spatial-frequency components of photographic positive and negative images was investigated by measuring recognition of bandpass-filtered photographs of faces. The results show that a 1.5 octave bandpass-filtered image contains sufficient visual information for good recognition performance, provided the filter is centred close to 20 cycles facewidth-1. At low spatial frequencies negatives are more difficult to recognize than positives, but at high spatial frequencies there is no difference in recognition, implying that it is the low-frequency components of negatives which present difficulties for the visual system.
D003118:Color Perception; D005145:Face; D005556:Form Perception; D006801:Humans; D010364:Pattern Recognition, Visual; D010812:Physical Stimulation