Local Intensity Order Pattern (LIOP) descriptor
liop.h implements Local Intensity Order Pattern descriptor (LIOP) of [32] . LIOP is a local image descriptor, similarly to the SIFT descriptor.
Getting started with LIOP demonstrates how to use the C API to compute the LIOP descriptor of a patch. For further details refer to:
- LIOP fundamentals - LIOP definition and parameters.
Getting started with LIOP
The following code fragment demonstrates how tow to use liop.h in a C program in order to compute the LIOP descriptor of an image patch.
#include <vl/liop.h>
// Create a new object instance (these numbers corresponds to parameter
// values proposed by authors of the paper, except for 41)
vl_size sideLength = 41 ;
VlLiopDesc * liop = vl_liopdesc_new_basic (sideLength);
// allocate the descriptor array
vl_size dimension = vl_liopdesc_get_dimension(liop) ;
// compute descriptor from a patch (an array of length sideLegnth *
// sideLength)
vl_liopdesc_process(liop, desc, patch) ;
// delete the object
vl_liopdesc_delete(liop) ;
void vl_liopdesc_delete(VlLiopDesc *self)
Delete object instance.
Definition: liop.c:417
void vl_liopdesc_process(VlLiopDesc *self, float *desc, float const *patch)
Compute liop descriptor for a patch.
Definition: liop.c:442
VlLiopDesc * vl_liopdesc_new_basic(vl_size sideLength)
Create a new object with default parameters.
Definition: liop.c:405
vl_size vl_liopdesc_get_dimension(VlLiopDesc const *self)
Get the dimension of a LIOP descriptor.
Definition: liop.c:569
Local Intensity Order Pattern (LIOP) descriptor (Local Intensity Order Pattern (LIOP) descriptor)
The image patch must be of odd side length and in single precision. There are several parameters affecting the LIOP descriptor. An example is the threshold used to discard low-contrast oder pattern in the computation of the statistics. This is changed by using vl_liopdesc_set_intensity_threshold.