3rdparty/OpenCV-2.3.0/modules/features2d/src/sift.cpp
static IplImage* downsample( IplImage* img )
{
  IplImage* smaller = cvCreateImage( cvSize(img->width / 2, img->height / 2),
                                     img->depth, img->nChannels );
  cvResize( img, smaller, CV_INTER_NN );

  return smaller;
}
/*
  Downsamples an image to a quarter of its size (half in each dimension)
  using nearest-neighbor interpolation

  @param img an image

  @return Returns an image whose dimensions are half those of img
*/
Downsamples an image to a quarter of its size (half in each dimension)
using nearest-neighbor interpolation
Downsamples an image to a quarter of its size ( half in each dimension ) using nearest - neighbor interpolation
static IplImage* downsample( IplImage* img )
{
  IplImage* smaller = cvCreateImage( cvSize(img->width / 2, img->height / 2),
                                     img->depth, img->nChannels );
  cvResize( img, smaller, CV_INTER_NN );
  return smaller;
}
static IplImage * downsample ( IplImage * img ) { IplImage * smaller = cvCreateImage ( cvSize ( img -> width / 2 , img -> height / 2 ) , img -> depth , img -> nChannels ) ; cvResize ( img , smaller , CV_INTER_NN ) ; return smaller ; }
Downsamples an image to a quarter of its size (half in each dimension)
using nearest-neighbor interpolation
Downsamples an image to a quarter of its size ( half in each dimension ) using nearest - neighbor interpolation