Generate a bandpass filter with sinusoidal shape.
gen_sin_bandpass generates a rotationally invariant bandpass filter with the response being a sinusoidal function in the frequency domain. The maximum of the sine (255) is determined by Frequency (distance from the DC term in pixels). The filter is always zero for the DC term, rises with the sine function up to Frequency, and drops for higher frequencies accordingly. The range of the sine used is from 0 to pi. All other points are set to zero.
ImageFilter (output_object) |
image(-array) -> object : byte |
Bandpass filter as image in the frequency domain. |
Frequency (input_control) |
real -> real |
Distance of the filter's maximum from the DC term. | |
Default value: 20 | |
Suggested values: 0.0, 5, 10, 15, 20, 25, 30, 35, 40, 45, 50, 55, 60, 65, 80, 100, 150, 200 | |
Range of values: 0.0 <= Frequency <= 1000 | |
Minimum increment: 1 | |
Recommended increment: 2 |
Size (input_control) |
integer -> integer |
Size (dimension) of the image (filter). | |
Default value: 512 | |
List of values: 8, 16, 32, 64, 128, 256, 512, 1024, 2048, 4096, 8192 |
gen_sin_bandpass returns TRUE if all parameters are correct. If necessary, an exception is raised.
gen_std_bandpass, gen_bandpass, gen_bandfilter, gen_highpass, gen_lowpass