text: /* 
   *  Copyright (c) 2008  Noah Snavely (snavely (at) cs.washington.edu)
   *    and the University of Washington
   *
   *  This program is free software; you can redistribute it and/or modify
   *  it under the terms of the GNU General Public License as published by
   *  the Free Software Foundation; either version 2 of the License, or
   *  (at your option) any later version.
   *
   *  This program is distributed in the hope that it will be useful,
   *  but WITHOUT ANY WARRANTY; without even the implied warranty of
   *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
   *  GNU General Public License for more details.
   *
   */
  
  /* pyramid.h */
  /* Routines for creating a gaussian pyramid from an image */
  
  #ifndef __pyramid_h__
  #define __pyramid_h__
  
  #ifdef __cplusplus
  extern "C" {
  #endif
  
  #include <sys/types.h>
  
  #include "image.h"
  #include "vector.h"
  
  typedef struct {
      u_int16_t num_levels;  /* Number of levels of the pyramid */
      u_int16_t w, h;        /* Width and height of the bottom of the pyramid */
      img_t **imgs;          /* Images in the pyramid */
  } img_pyr_t;
  
  img_pyr_t *img_pyramid_new(int w, int h);
  
  /* Create a gaussian pyramid from an image, with a number of extra levels */
  img_pyr_t *img_create_gaussian_pyramid(img_t *img, int extra);
  
  /* Use linear interpolation to compute the color of the point (x,y) 
   * in the given image pyramid */
  fcolor_t img_pyramid_pixel_lerp(img_pyr_t *pyr, double x, double y, 
                                  double scale);
  
  #ifdef __cplusplus
  }
  #endif
  
  #endif /* __pyramid_h__ */
  