/******************************************************************************* License: This software and/or related materials was developed at the National Institute of Standards and Technology (NIST) by employees of the Federal Government in the course of their official duties. Pursuant to title 17 Section 105 of the United States Code, this software is not subject to copyright protection and is in the public domain. This software and/or related materials have been determined to be not subject to the EAR (see Part 734.3 of the EAR for exact details) because it is a publicly available technology and software, and is freely distributed to any interested party with no licensing requirements. Therefore, it is permissible to distribute this software as a free download from the internet. Disclaimer: This software and/or related materials was developed to promote biometric standards and biometric technology testing for the Federal Government in accordance with the USA PATRIOT Act and the Enhanced Border Security and Visa Entry Reform Act. Specific hardware and software products identified in this software were used in order to perform the software development. In no case does such identification imply recommendation or endorsement by the National Institute of Standards and Technology, nor does it imply that the products and equipment identified are necessarily the best available for the purpose. This software and/or related materials are provided "AS-IS" without warranty of any kind including NO WARRANTY OF PERFORMANCE, MERCHANTABILITY, NO WARRANTY OF NON-INFRINGEMENT OF ANY 3RD PARTY INTELLECTUAL PROPERTY or FITNESS FOR A PARTICULAR PURPOSE or for any purpose whatsoever, for the licensed product, however used. In no event shall NIST be liable for any damages and/or costs, including but not limited to incidental or consequential damages of any kind, including economic damage or injury to property and lost profits, regardless of whether NIST shall be advised, have reason to know, or in fact shall know of the possibility. By using this software, you agree to bear all risk relating to quality, use and performance of the software and/or related materials. You agree to hold the Government harmless from any claim arising from your use of the software. *******************************************************************************/ /*********************************************************************** LIBRARY: LFS - NIST Latent Fingerprint System FILE: MORPH.C AUTHOR: Michael D. Garris DATE: 10/04/1999 UPDATED: 10/26/1999 by MDG To avoid indisciminate erosion of pixels along the edge of the binary image. UPDATED: 03/16/2005 by MDG Contains general support image morphology routines required by the NIST Latent Fingerprint System (LFS). *********************************************************************** ROUTINES: erode_charimage_2() dilate_charimage_2() get_south8_2() get_north8_2() get_east8_2() get_west8_2() ***********************************************************************/ #include #include /************************************************************************* ************************************************************************** #cat: erode_charimage_2 - Erodes an 8-bit image by setting true pixels to zero #cat: if any of their 4 neighbors is zero. Allocation of the #cat: output image is the responsibility of the caller. The #cat: input image remains unchanged. This routine will NOT #cat: erode pixels indiscriminately along the image border. Input: inp - input 8-bit image to be eroded iw - width (in pixels) of image ih - height (in pixels) of image Output: out - contains to the resulting eroded image **************************************************************************/ void erode_charimage_2(unsigned char *inp, unsigned char *out, const int iw, const int ih) { int row, col; unsigned char *itr = inp, *otr = out; memcpy(out, inp, iw*ih); /* for true pixels. kill pixel if there is at least one false neighbor */ for ( row = 0 ; row < ih ; row++ ) for ( col = 0 ; col < iw ; col++ ) { if (*itr) /* erode only operates on true pixels */ { /* more efficient with C's left to right evaluation of */ /* conjuctions. E N S functions not executed if W is false */ if (!(get_west8_2 ((char *)itr, col , 1 ) && get_east8_2 ((char *)itr, col, iw , 1 ) && get_north8_2((char *)itr, row, iw , 1 ) && get_south8_2((char *)itr, row, iw, ih, 1))) *otr = 0; } itr++ ; otr++; } } /************************************************************************* ************************************************************************** #cat: dilate_charimage_2 - Dilates an 8-bit image by setting false pixels to #cat: one if any of their 4 neighbors is non-zero. Allocation #cat: of the output image is the responsibility of the caller. #cat: The input image remains unchanged. Input: inp - input 8-bit image to be dilated iw - width (in pixels) of image ih - height (in pixels) of image Output: out - contains to the resulting dilated image **************************************************************************/ void dilate_charimage_2(unsigned char *inp, unsigned char *out, const int iw, const int ih) { int row, col; unsigned char *itr = inp, *otr = out; memcpy(out, inp, iw*ih); /* for all pixels. set pixel if there is at least one true neighbor */ for ( row = 0 ; row < ih ; row++ ) for ( col = 0 ; col < iw ; col++ ) { if (!*itr) /* pixel is already true, neighbors irrelevant */ { /* more efficient with C's left to right evaluation of */ /* conjuctions. E N S functions not executed if W is false */ if (get_west8_2 ((char *)itr, col , 0) || get_east8_2 ((char *)itr, col, iw , 0) || get_north8_2((char *)itr, row, iw , 0) || get_south8_2((char *)itr, row, iw, ih, 0)) *otr = 1; } itr++ ; otr++; } } /************************************************************************* ************************************************************************** #cat: get_south8_2 - Returns the value of the 8-bit image pixel 1 below the #cat: current pixel if defined else it returns (char)0. Input: ptr - points to current pixel in image row - y-coord of current pixel iw - width (in pixels) of image ih - height (in pixels) of image failcode - return value if desired pixel does not exist Return Code: Zero - if neighboring pixel is undefined (outside of image boundaries) Pixel - otherwise, value of neighboring pixel **************************************************************************/ char get_south8_2(char *ptr, const int row, const int iw, const int ih, const int failcode) { if (row >= ih-1) /* catch case where image is undefined southwards */ return failcode; /* use plane geometry and return code. */ return *(ptr+iw); } /************************************************************************* ************************************************************************** #cat: get_north8_2 - Returns the value of the 8-bit image pixel 1 above the #cat: current pixel if defined else it returns (char)0. Input: ptr - points to current pixel in image row - y-coord of current pixel iw - width (in pixels) of image failcode - return value if desired pixel does not exist Return Code: Zero - if neighboring pixel is undefined (outside of image boundaries) Pixel - otherwise, value of neighboring pixel **************************************************************************/ char get_north8_2(char *ptr, const int row, const int iw, const int failcode) { if (row < 1) /* catch case where image is undefined northwards */ return failcode; /* use plane geometry and return code. */ return *(ptr-iw); } /************************************************************************* ************************************************************************** #cat: get_east8_2 - Returns the value of the 8-bit image pixel 1 right of the #cat: current pixel if defined else it returns (char)0. Input: ptr - points to current pixel in image col - x-coord of current pixel iw - width (in pixels) of image failcode - return value if desired pixel does not exist Return Code: Zero - if neighboring pixel is undefined (outside of image boundaries) Pixel - otherwise, value of neighboring pixel **************************************************************************/ char get_east8_2(char *ptr, const int col, const int iw, const int failcode) { if (col >= iw-1) /* catch case where image is undefined eastwards */ return failcode; /* use plane geometry and return code. */ return *(ptr+ 1); } /************************************************************************* ************************************************************************** #cat: get_west8_2 - Returns the value of the 8-bit image pixel 1 left of the #cat: current pixel if defined else it returns (char)0. Input: ptr - points to current pixel in image col - x-coord of current pixel failcode - return value if desired pixel does not exist Return Code: Zero - if neighboring pixel is undefined (outside of image boundaries) Pixel - otherwise, value of neighboring pixel **************************************************************************/ char get_west8_2(char *ptr, const int col, const int failcode) { if (col < 1) /* catch case where image is undefined westwards */ return failcode; /* use plane geometry and return code. */ return *(ptr- 1); }