grass
7.8.6
About: GRASS (Geographic Resources Analysis Support System) is a raster- and vector-based GIS, image processing system, graphics production system and spatial modeling system.
Fossies Dox: grass-7.8.6.tar.gz ("unofficial" and yet experimental doxygen-generated source code documentation) |
Zero Crossing functions. More...
#include <stdio.h>
#include <math.h>
Go to the source code of this file.
Macros | |
#define | TINY 1.0e-3 |
Functions | |
int | G_math_findzc (double conv[], int size, double zc[], double thresh, int num_orients) |
Finds locations and orientations of zero crossings. More... | |
Zero Crossing functions.
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.
You should have received a copy of the GNU General Public License along with this program; if not, write to the Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
Definition in file findzc.c.
int G_math_findzc | ( | double | conv[], |
int | size, | ||
double | zc[], | ||
double | thresh, | ||
int | num_orients | ||
) |
Finds locations and orientations of zero crossings.
Finds the locations and orientations of zero crossings in the input array conv, which is the result of the convolution of the Marr-Hildreth operator with the image. The output array is zc, which is non-zero only at zero crossing pixels. At those pixels, the value is 1 + (orientation), where orientation is a value from 0 to num_orients.
[in] | conv | input |
[in] | size | size of largest matrix column or row |
[out] | zc | output |
[in] | thresh | magnitude threshold |
[in] | num_orients |