Index: /trunk/Ohana/src/opihi/cmd.data/Makefile
===================================================================
--- /trunk/Ohana/src/opihi/cmd.data/Makefile	(revision 16004)
+++ /trunk/Ohana/src/opihi/cmd.data/Makefile	(revision 16005)
@@ -50,4 +50,5 @@
 $(SRC)/grid.$(ARCH).o		\
 $(SRC)/gridify.$(ARCH).o       \
+$(SRC)/grow.$(ARCH).o		\
 $(SRC)/ungridify.$(ARCH).o     \
 $(SRC)/histogram.$(ARCH).o	\
Index: /trunk/Ohana/src/opihi/cmd.data/grow.c
===================================================================
--- /trunk/Ohana/src/opihi/cmd.data/grow.c	(revision 16005)
+++ /trunk/Ohana/src/opihi/cmd.data/grow.c	(revision 16005)
@@ -0,0 +1,50 @@
+# include "data.h"
+
+int grow (int argc, char **argv) {
+  
+  int i, j, nx, ny, npix, nsum, Nx, Ny;
+  float *input, *output;
+  Buffer *in;
+
+  if (argc != 3) {
+    gprint (GP_ERR, "USAGE: grow (input) (npix)\n");
+    return (FALSE);
+  }
+  
+  if ((in  = SelectBuffer (argv[1], OLDBUFFER, TRUE)) == NULL) return (FALSE);
+  npix = atoi (argv[2]);
+
+  Nx = in[0].matrix.Naxis[0];
+  Ny = in[0].matrix.Naxis[1];
+  ALLOCATE (output, float, Nx*Ny);
+  memset (output, 0, Nx*Ny*sizeof(float));
+
+  input = (float *) in[0].matrix.buffer;
+
+  for (j = 0; j < Ny; j++) {
+    for (i = 0; i < Nx; i++) {
+      nsum = 0;
+      for (ny = -1; ny <= +1; ny++) {
+	if (j + ny < 0) continue;
+	if (j + ny >= Ny) continue;
+	for (nx = -1; nx <= +1; nx++) {
+	  if (i + nx < 0) continue;
+	  if (i + nx >= Nx) continue;
+	  if (!nx && !ny) continue;
+	  if (input[i + nx + Nx*(j + ny)] == 0) continue;
+	  nsum ++;
+	}
+      }
+      if (nsum >= npix) {
+	output[i + j*Nx] = 1;
+      } else {
+	output[i + j*Nx] = input[i + j*Nx];
+      }
+    }
+  }
+  
+  free (in[0].matrix.buffer);
+  in[0].matrix.buffer = (char *) output;
+  return (TRUE);
+}
+
Index: /trunk/Ohana/src/opihi/cmd.data/init.c
===================================================================
--- /trunk/Ohana/src/opihi/cmd.data/init.c	(revision 16004)
+++ /trunk/Ohana/src/opihi/cmd.data/init.c	(revision 16005)
@@ -35,4 +35,5 @@
 int grid             PROTO((int, char **));
 int gridify          PROTO((int, char **));
+int grow             PROTO((int, char **));
 int ungridify        PROTO((int, char **));
 int histogram        PROTO((int, char **));
@@ -151,4 +152,5 @@
   {"grid",    	   grid,	     "plot cartesian grid"},
   {"gridify",      gridify,	     "convert vector triplet to buffer"},
+  {"grow",    	   grow,	     "grow a mask"},
   {"ungridify",    ungridify,        "convert buffer region to vector triplet"},
   {"header",       header,	     "print buffer header"},