quickshift.h File Reference

Quick shift (Quick shift image segmentation) More...

#include "generic.h"
#include "mathop.h"

Data Structures
struct	VlQS
	quick shift results More...

Macros
#define	VL_QS_INF   VL_INFINITY_D /* Change to _F for float math */
	quick shift infinity constant

Typedefs
typedef double	vl_qs_type
	quick shift datatype

Functions
Create and destroy
VlQS *	vl_quickshift_new (vl_qs_type const *im, int height, int width, int channels)
	Create a quick shift object. More...
void	vl_quickshift_delete (VlQS *q)
	Delete quick shift object. More...
Process data
void	vl_quickshift_process (VlQS *q)
	Create a quick shift objet. More...
Retrieve data and parameters
vl_qs_type	vl_quickshift_get_max_dist (VlQS const *q)
	Get tau. More...
vl_qs_type	vl_quickshift_get_kernel_size (VlQS const *q)
	Get sigma. More...
vl_bool	vl_quickshift_get_medoid (VlQS const *q)
	Get medoid. More...
int *	vl_quickshift_get_parents (VlQS const *q)
	Get parents. More...
vl_qs_type *	vl_quickshift_get_dists (VlQS const *q)
	Get dists. More...
vl_qs_type *	vl_quickshift_get_density (VlQS const *q)
	Get density. More...
Set parameters
void	vl_quickshift_set_max_dist (VlQS *q, vl_qs_type tau)
	Set max distance. More...
void	vl_quickshift_set_kernel_size (VlQS *q, vl_qs_type sigma)
	Set sigma. More...
void	vl_quickshift_set_medoid (VlQS *q, vl_bool medoid)
	Set medoid. More...

Detailed Description

Author

Andrea Vedaldi

Brian Fulkerson

Function Documentation

vl_quickshift_delete()

void vl_quickshift_delete

(

VlQS *

q

)

Parameters

q	quick shift object.

vl_quickshift_get_density()

vl_qs_type * vl_quickshift_get_density ( VlQS const *  q )

inline

Parameters

q	quick shift object.

Returns

the estimate of the density at each pixel.

vl_quickshift_get_dists()

vl_qs_type * vl_quickshift_get_dists ( VlQS const *  q )

inline

Parameters

q	quick shift object.

Returns

for each pixel, the distance in feature space to the pixel that is its parent in the quick shift tree. The distance is set to 'inf' if the pixel is a root node.

vl_quickshift_get_kernel_size()

vl_qs_type vl_quickshift_get_kernel_size ( VlQS const *  q )

inline

Parameters

q	quick shift object.

Returns

the standard deviation of the kernel used in the Parzen density estimate.

vl_quickshift_get_max_dist()

vl_qs_type vl_quickshift_get_max_dist ( VlQS const *  q )

inline

Parameters

q	quick shift object.

Returns

the maximum distance in the feature space between nodes in the quick shift tree.

vl_quickshift_get_medoid()

vl_bool vl_quickshift_get_medoid ( VlQS const *  q )

inline

Parameters

q	quick Shift object.

Returns

true if medoid shift is used instead of quick shift.

vl_quickshift_get_parents()

int * vl_quickshift_get_parents ( VlQS const *  q )

inline

Parameters

q	quick shift object.

Returns

a height x width matrix where each element contains the linear index of its parent node. The node is a root if its value is its own linear index.

vl_quickshift_new()

VlQS* vl_quickshift_new	(	vl_qs_type const *	image,
		int	height,
		int	width,
		int	channels
	)

Parameters

image	the image.
height	the height (number of rows) of the image.
width	the width (number of columns) of the image.
channels	the number of channels of the image.

Returns

new quick shift object.

The image is an array of vl_qs_type values with three dimensions (respectively widht, height, and channels). Typically, a color (e.g, RGB) image has three channels. The linear index of a pixel is computed with: channels * width* height + row + height * col.

vl_quickshift_process()

void vl_quickshift_process

(

VlQS *

q

)

Parameters

q	quick shift object.

vl_quickshift_set_kernel_size()

void vl_quickshift_set_kernel_size ( VlQS *  q, vl_qs_type  sigma  )

inline

Parameters

q	quick shift object.
sigma	standard deviation of the kernel used in the Parzen density estimate.

vl_quickshift_set_max_dist()

void vl_quickshift_set_max_dist ( VlQS *  q, vl_qs_type  tau  )

inline

Parameters

q	quick shift object.
tau	the maximum distance in the feature space between nodes in the quick shift tree.

vl_quickshift_set_medoid()

void vl_quickshift_set_medoid ( VlQS *  q, vl_bool  medoid  )

inline

Parameters

q	quick shift object.
medoid	true to use kernelized medoid shift, false (default) uses quick shift.