Method Image.Image()->apply_matrix()

Method apply_matrix

object apply_matrix(array(array(int|array(int))) matrix)
object apply_matrix(array(array(int|array(int))) matrix, int r, int g, int b)
object apply_matrix(array(array(int|array(int))) matrix, int r, int g, int b, int|float div)

Description

Applies a pixel-transform matrix, or filter, to the image.

                       2   2
pixel(x,y)= base+ k ( sum sum pixel(x+k-1,y+l-1)*matrix(k,l) )
                      k=0 l=0

1/k is sum of matrix, or sum of matrix multiplied with div. base is given by r,g,b and is normally black.

blur (ie a 2d gauss function): ({({1,2,1}), ({2,5,2}), ({1,2,1})})
		original
sharpen (k>8, preferably 12 or 16): ({({-1,-1,-1}), ({-1, k,-1}), ({-1,-1,-1})})
edge detect: ({({1, 1,1}), ({1,-8,1}), ({1, 1,1})})
horisontal edge detect (get the idea): ({({0, 0,0}), ({1,-2,1}), ({0, 0,0})})
emboss (might prefer to begin with a grey image): ({({2, 1, 0}), ({1, 0,-1}), ({0,-1,-2})}), 128,128,128, 3
		greyed

This function is not very fast.

Parameter array

the matrix; innermost is a value or an array with red, green, blue values for red, green, blue separation.

Parameter r

Parameter g

Parameter b

base level of result, default is zero

Parameter div

division factor, default is 1.0.

Returns

the new image object