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dsift.c File Reference

Dense SIFT - Definition. More...

`#include "dsift.h"`
`#include "pgm.h"`
`#include "mathop.h"`
`#include "imopv.h"`
`#include <math.h>`
`#include <string.h>`

## Functions

float * | _vl_dsift_new_kernel (int binSize, int numBins, int binIndex, double windowSize)
| Initialize new convolution kernel. More...
float | _vl_dsift_normalize_histogram (float *begin, float *end)
| Normalize histogram. More...
static void | _vl_dsift_free_buffers (VlDsiftFilter *self)
| Free internal buffers. More...
void | _vl_dsift_update_buffers (VlDsiftFilter *self)
| Updates internal buffers to current geometry. More...
static void | _vl_dsift_alloc_buffers (VlDsiftFilter *self)
| Allocate internal buffers. More...
VlDsiftFilter * | vl_dsift_new (int imWidth, int imHeight)
| Create a new DSIFT filter. More...
VlDsiftFilter * | vl_dsift_new_basic (int imWidth, int imHeight, int step, int binSize)
| Create a new DSIFT filter (basic interface) More...
void | vl_dsift_delete (VlDsiftFilter *self)
| Delete DSIFT filter. More...
void | _vl_dsift_with_gaussian_window (VlDsiftFilter *self)
| Process with Gaussian window. More...
void | _vl_dsift_with_flat_window (VlDsiftFilter *self)
| Process with flat window. More...
void | vl_dsift_process (VlDsiftFilter *self, float const *im)
| Compute keypoints and descriptors. More...

## Detailed Description

Author
  Andrea Vedaldi
  Brian Fulkerson

## Function Documentation

static void _vl_dsift_alloc_buffers | ( | VlDsiftFilter * | self | ) |

static

Parameters

  self | DSIFT filter.

The function (re)allocates the internal buffers in accordance with the current image and descriptor geometry.

static void _vl_dsift_free_buffers | ( | VlDsiftFilter * | self | ) |

static

Parameters

  self | DSIFT filter.

float* _vl_dsift_new_kernel | ( | int | binSize,
|  | int | numBins,
|  | int | binIndex,
|  | double | windowSize
| ) |  |

Parameters

  binSize |
  numBins |
  binIndex | negative to use flat window.
  windowSize |

Returns
  a pointer to new filter.

float _vl_dsift_normalize_histogram | ( | float * | begin,
|  | float * | end
| ) |  |

inline

Parameters

  begin | first element of the histogram.
  end | last plus one element of the histogram.

The function divides the specified histogram by its l2 norm.

void _vl_dsift_update_buffers | ( | VlDsiftFilter * | self | ) |

void _vl_dsift_with_flat_window | ( | VlDsiftFilter * | self | ) |

inline

Parameters

  self | DSIFT filter object.

void _vl_dsift_with_gaussian_window | ( | VlDsiftFilter * | self | ) |

inline

Parameters

  self | DSIFT filter.

void vl_dsift_delete | ( | VlDsiftFilter * | self | ) |

Parameters

  self | DSIFT filter.

VlDsiftFilter* vl_dsift_new | ( | int | imWidth,
|  | int | imHeight
| ) |  |

Parameters

  imWidth | width of the image.
  imHeight | height of the image

Returns
  new filter.

VlDsiftFilter* vl_dsift_new_basic | ( | int | imWidth,
|  | int | imHeight,
|  | int | step,
|  | int | binSize
| ) |  |

Parameters

  imWidth | width of the image.
  imHeight | height of the image.
  step | sampling step.
  binSize | bin size.

Returns
  new filter.

The descriptor geometry matches the standard SIFT descriptor.

void vl_dsift_process | ( | VlDsiftFilter * | self,
|  | float const * | im
| ) |  |

Parameters

  self | DSIFT filter.
  im | image data.