Low spatial frequencies, on the other hand, represent global information about the shape, such as general orientation and proportions.
They will respond to high spatial frequencies but, as mentioned above, the response is non-linear.
They can equally be applied to analyze spatial frequencies, and indeed for nearly any function domain.
The high spatial frequencies in an image give it its fine details.
Blurring is accomplished by reducing the contrast only of the high spatial frequencies.
This minimum difference will change with the spatial frequency of the bar target used.
An operator uses a series of 4-bar targets of different spatial frequencies.
The corresponding spatial frequencies used in each test are also stored into an array.
People noticed later when reading text of the same spatial frequency, in a book say, that it looked pink.
They also concluded that at lower spatial frequencies White's illusion is still present.
