1 files changed, 253 insertions, 0 deletions
diff --git a/editor/pgmmorphconv.c b/editor/pgmmorphconv.c
new file mode 100644
index 00000000..abc4e718
--- /dev/null
+++ b/editor/pgmmorphconv.c
@@ -0,0 +1,253 @@
+/* pgmmorphconv.c - morphological convolutions on a graymap: dilation and 
+** erosion
+**
+** Copyright (C) 2000 by Luuk van Dijk/Mind over Matter
+**
+** Based on 
+** pnmconvol.c - general MxN convolution on a portable anymap
+**
+** Copyright (C) 1989, 1991 by Jef Poskanzer.
+**
+** Permission to use, copy, modify, and distribute this software and its
+** documentation for any purpose and without fee is hereby granted, provided
+** that the above copyright notice appear in all copies and that both that
+** copyright notice and this permission notice appear in supporting
+** documentation.  This software is provided "as is" without express or
+** implied warranty.
+*/
+
+#include "pm_c_util.h"
+#include "pgm.h"
+
+
+/************************************************************
+ * Dilate 
+ ************************************************************/
+
+static int 
+dilate( bit** template, int trowso2, int tcolso2, 
+        gray** in_image, gray** out_image, 
+        int rows, int cols ){
+
+  int c, r, tc, tr;
+  int templatecount;
+  gray source;
+
+  for( c=0; c<cols; ++c)
+    for( r=0; r<rows; ++r )
+      out_image[r][c] = 0;   /* only difference with erode is here and below */
+  
+  /* 
+   *  for each non-black pixel of the template
+   *  add in to out
+   */
+
+  templatecount=0;
+
+  for( tr=-trowso2; tr<=trowso2; ++tr ){
+    for( tc=-tcolso2; tc<=tcolso2; ++tc ){
+
+      if( template[trowso2+tr][tcolso2+tc] == PBM_BLACK ) continue;
+
+      ++templatecount;
+
+      for( r= ((tr>0)?0:-tr) ; r< ((tr>0)?(rows-tr):rows) ; ++r ){
+        for( c= ((tc>0)?0:-tc) ; c< ((tc>0)?(cols-tc):cols) ; ++c ){
+          source = in_image[r+tr][c+tc];
+          out_image[r][c] = MAX(source, out_image[r][c]);
+        } /* for c */
+      } /* for r */
+    } /* for tr */
+  } /* for tc */
+
+  return templatecount;
+
+} /* dilate */
+
+
+
+/************************************************************
+ * Erode: same as dilate except !!!!
+ ************************************************************/
+
+static int 
+erode( bit** template, int trowso2, int tcolso2, 
+       gray** in_image, gray** out_image, 
+       int rows, int cols ){
+
+  int c, r, tc, tr;
+  int templatecount;
+  gray source;
+
+  for( c=0; c<cols; ++c)
+    for( r=0; r<rows; ++r )
+      out_image[r][c] = PGM_MAXMAXVAL; /* !!!! */
+  
+  /* 
+   *  for each non-black pixel of the template
+   *  add in to out
+   */
+
+  templatecount=0;
+
+  for( tr=-trowso2; tr<=trowso2; ++tr ){
+    for( tc=-tcolso2; tc<=tcolso2; ++tc ){
+
+      if( template[trowso2+tr][tcolso2+tc] == PBM_BLACK ) continue;
+
+      ++templatecount;
+
+      for( r= ((tr>0)?0:-tr) ; r< ((tr>0)?(rows-tr):rows) ; ++r ){
+    for( c= ((tc>0)?0:-tc) ; c< ((tc>0)?(cols-tc):cols) ; ++c ){
+
+      source = in_image[r+tr][c+tc];
+      out_image[r][c] = MIN(source, out_image[r][c]);
+      
+    } /* for c */
+      } /* for r */
+
+
+
+    } /* for tr */
+  } /* for tc */
+
+  return templatecount;
+
+} /* erode */
+
+
+
+/************************************************************
+ *  Main
+ ************************************************************/
+
+
+int main( int argc, char* argv[] ){
+
+  int argn;
+  char operation;
+  const char* usage = "-dilate|-erode|-open|-close <templatefile> [pgmfile]";
+
+  FILE* tifp;   /* template */
+  int tcols, trows;
+  int tcolso2, trowso2;
+  bit** template;
+
+
+  FILE*  ifp;   /* input image */
+  int cols, rows;
+  gray maxval;
+
+  gray** in_image;
+  gray** out_image;
+
+  int templatecount=0;
+
+  pgm_init( &argc, argv );
+
+  /*
+   *  parse arguments
+   */ 
+  
+  ifp = stdin;
+  operation = 'd';
+
+  argn=1;
+  
+  if( argn == argc ) pm_usage( usage );
+  
+  if( pm_keymatch( argv[argn], "-erode", 2  )) { operation='e'; argn++; }
+  else
+  if( pm_keymatch( argv[argn], "-dilate", 2 )) { operation='d'; argn++; }
+  else
+  if( pm_keymatch( argv[argn], "-open", 2   )) { operation='o'; argn++; }
+  else
+  if( pm_keymatch( argv[argn], "-close", 2  )) { operation='c'; argn++; }
+  
+  if( argn == argc ) pm_usage( usage );
+  
+  tifp = pm_openr( argv[argn++] );
+  
+  if( argn != argc ) ifp = pm_openr( argv[argn++] );
+
+  if( argn != argc ) pm_usage( usage );
+
+  
+  /* 
+   * Read in the template matrix.
+   */
+
+  template = pbm_readpbm( tifp, &tcols, &trows );
+  pm_close( tifp );
+
+  if( tcols % 2 != 1 || trows % 2 != 1 )
+    pm_error("the template matrix must have an odd number of "
+             "rows and columns" );
+
+  /* the reason is that we want the middle pixel to be the origin */
+  tcolso2 = tcols / 2; /* template coords run from -tcols/2 .. 0 .. +tcols/2 */
+  trowso2 = trows / 2;
+
+#if 0
+  fprintf(stderr, "template: %d  x %d\n", trows, tcols);
+  fprintf(stderr, "half: %d  x %d\n", trowso2, tcolso2);
+#endif
+
+  /*
+   * Read in the image
+   */
+  
+  in_image = pgm_readpgm( ifp, &cols, &rows, &maxval);
+
+  if( cols < tcols || rows < trows )
+    pm_error("the image is smaller than the convolution matrix" );
+  
+#if 0
+  fprintf(stderr, "image: %d  x %d (%d)\n", rows, cols, maxval);
+#endif
+
+  /* 
+   * Allocate  output buffer and initialize with min or max value 
+   */
+
+  out_image = pgm_allocarray( cols, rows );
+  
+  if( operation == 'd' ){
+    templatecount = dilate(template, trowso2, tcolso2, 
+               in_image, out_image, rows, cols);
+  } 
+  else if( operation == 'e' ){
+    templatecount = erode(template, trowso2, tcolso2, 
+              in_image, out_image, rows, cols);
+  }
+  else if( operation == 'o' ){
+    gray ** eroded_image;
+    eroded_image = pgm_allocarray( cols, rows );
+    templatecount = erode(template, trowso2, tcolso2, 
+                          in_image, eroded_image, rows, cols);
+    templatecount = dilate(template, trowso2, tcolso2, 
+                           eroded_image, out_image, rows, cols);
+    pgm_freearray( eroded_image, rows );
+  }
+  else if( operation == 'c' ){
+    gray ** dilated_image;
+    dilated_image = pgm_allocarray( cols, rows );
+    templatecount = dilate(template, trowso2, tcolso2, 
+                           in_image, dilated_image, rows, cols);
+    templatecount = erode(template, trowso2, tcolso2, 
+                          dilated_image, out_image, rows, cols);
+    pgm_freearray( dilated_image, rows );
+  }
+  
+  if(templatecount == 0 ) pm_error( "The template was empty!" );
+
+  pgm_writepgm( stdout, out_image, cols, rows, maxval, 1 );
+
+  pgm_freearray( out_image, rows );
+  pgm_freearray( in_image, rows );
+  pm_close( ifp );
+
+  exit( 0 );
+
+} /* main */
+