af_medfilt

The C interface for medfilt. More...

afError	af_medfilt_B (char *d_out, unsigned m, unsigned n, const char *d_in, const unsigned *h_W)
	Median filtering of a matrix using the specified window (or a 3 x 3 default window). More...
afError	af_medfilt_c (unsigned char *d_out, unsigned m, unsigned n, const unsigned char *d_in, const unsigned *h_W)
	Medfilt: 8-bit unsigned int. More...
afError	af_medfilt_I (int *d_out, unsigned m, unsigned n, const int *d_in, const unsigned *h_W)
	Medfilt: int data. More...
afError	af_medfilt_U (unsigned *d_out, unsigned m, unsigned n, const unsigned *d_in, const unsigned *h_W)
	Medfilt: unsigned int data. More...
afError	af_medfilt_S (float *d_out, unsigned m, unsigned n, const float *d_in, const unsigned *h_W)
	Medfilt: single-precision data. More...
afError	af_medfilt_D (double *d_out, unsigned m, unsigned n, const double *d_in, const unsigned *h_W)
	Medfilt: double-precision data. More...

Detailed Description

The C interface for medfilt.

Apply a median filter of a given size to an image. A median filter is similar to the arbitrary filter except that instead of a weighted sum, the median value of the pixels covered by the kernel is returned.

For instance, if we apply a median filter to an simple sequential image:

array = array(seq(1,16), 4, 4);
print(a);
//a = 1.0000        5.0000        9.0000       13.0000
//    2.0000        6.0000       10.0000       14.0000
//    3.0000        7.0000       11.0000       15.0000
//    4.0000        8.0000       12.0000       16.0000

print(medfilt(a, 3, 3));
//    0.0000        2.0000        6.0000        0.0000
//    2.0000        6.0000       10.0000       10.0000
//    3.0000        7.0000       11.0000       11.0000
//    0.0000        4.0000        8.0000        0.0000

This example highlights that pixels outside the image are treated as zeros. So, for the first pixel, the neighborhood looks like:

0 0 0
0 1 5
0 2 6

the median of which is zero.

Function Documentation

afError af_medfilt_B	(	char *	d_out,
		unsigned	m,
		unsigned	n,
		const char *	d_in,
		const unsigned *	h_W
	)

Median filtering of a matrix using the specified window (or a 3 x 3 default window).

Parameters

[out]	d_out	Output buffer to hold the filtered result
[in]	d_in	Input buffer containing matrix to be filtered
[in]	m	Number of rows in input matrix
[in]	n	Number of columns in input matrix
[in]	h_W	2x1 Vector specifying window dimensions to be usedMedfilt: Binary input

afError af_medfilt_c	(	unsigned char *	d_out,
		unsigned	m,
		unsigned	n,
		const unsigned char *	d_in,
		const unsigned *	h_W
	)

Medfilt: 8-bit unsigned int.

afError af_medfilt_I	(	int *	d_out,
		unsigned	m,
		unsigned	n,
		const int *	d_in,
		const unsigned *	h_W
	)

Medfilt: int data.

afError af_medfilt_U	(	unsigned *	d_out,
		unsigned	m,
		unsigned	n,
		const unsigned *	d_in,
		const unsigned *	h_W
	)

Medfilt: unsigned int data.

afError af_medfilt_S	(	float *	d_out,
		unsigned	m,
		unsigned	n,
		const float *	d_in,
		const unsigned *	h_W
	)

Medfilt: single-precision data.

afError af_medfilt_D	(	double *	d_out,
		unsigned	m,
		unsigned	n,
		const double *	d_in,
		const unsigned *	h_W
	)

Medfilt: double-precision data.