DD::Image::Filter::Coefficients Struct Reference

#include <Filter.h>

Public Member Functions
float	apply (const float *array) const
float	apply (const float *array, int left, int right) const

Public Attributes
const float *	array
	coefficients
int	delta
	distance between cefficients in array
int	count
	number of coefficients
int	first
	index to multiply by array[0]
float	normalize
	common multiplier to make it sum to 1

Detailed Description

Coefficients for the filter at a particular position & width.

Member Function Documentation

apply()

float Filter::Coefficients::apply

(

const float *

array

)

const

Multiply an array of pixels by the filter coefficients and return the sum of the results. It is equivalent to the following code:

float sum = pixels[first]*array[0];
for (int i = 1; i < count; i++) sum += pixels[first+i]*array[delta*i];
return sum*normalize;

Note that in many cases your input is a bounded array or is not an array at all. You can either write equivalent code to read your source, or copy it to an array and call this.

References array, count, delta, first, and normalize.