Fixed resizing of resulting jpeg images: leave one grid point at boundaries

as interpolation stencil.


git-svn-id: http://svn.cactuscode.org/arrangements/CactusIO/IOJpeg/trunk@107 eff87b29-5268-4891-90a3-a07138403961

1 files changed, 12 insertions, 9 deletions

diff --git a/src/Write.c b/src/Write.c
index 8c416c9..b978f66 100644
--- a/src/Write.c
+++ b/src/Write.c
@@ -242,7 +242,7 @@ static void *RefineData (CCTK_INT input_dims[2], const void *input_data)
   CCTK_REAL coord_delta[2];
   const CCTK_INT array_type_codes[2] = {CCTK_VARIABLE_REAL, CCTK_VARIABLE_REAL};
   CCTK_REAL *interp_coords[2], *refined_data;
-  int i, j, interp_handle, N_interp_points;
+  int i, j, interp_handle, table_handle, N_interp_points;
   CCTK_INT output_dims[2];
   DECLARE_CCTK_PARAMETERS
 
@@ -256,27 +256,29 @@ static void *RefineData (CCTK_INT input_dims[2], const void *input_data)
     return (NULL);
   }
 
+  table_handle = Util_TableCreateFromString ("order = 1");
   coord_delta[0] = coord_delta[1] = refinement_factor;
 
-  output_dims[0] = refinement_factor * (input_dims[0] - 1);
-  output_dims[1] = refinement_factor * (input_dims[1] - 1);
+  /* leave one grid point at the boundary as interpolation stencil */
+  output_dims[0] = refinement_factor * (input_dims[0] - 1) - 2;
+  output_dims[1] = refinement_factor * (input_dims[1] - 1) - 2;
   N_interp_points = output_dims[0] * output_dims[1];
 
   interp_coords[0] = malloc (2 * N_interp_points * sizeof (CCTK_REAL));
-  interp_coords[1] = interp_coords[0];
-  for (i = 0; i < output_dims[0]; i++)
+  interp_coords[1] = interp_coords[0] + N_interp_points;
+  for (j = 0; j < output_dims[1]; j++)
   {
-    for (j = 0; j < output_dims[1]; j++)
+    for (i = 0; i < output_dims[0]; i++)
     {
-      *interp_coords[0]++ = i;
-      *interp_coords[1]++ = j;
+      *interp_coords[0]++ = i + 1;
+      *interp_coords[1]++ = j + 1;
     }
   }
   interp_coords[0] -= N_interp_points;
   interp_coords[1] -= N_interp_points;
 
   refined_data = malloc (N_interp_points * sizeof (CCTK_REAL));
-  if (CCTK_InterpLocalUniform (2, interp_handle, -1,
+  if (CCTK_InterpLocalUniform (2, interp_handle, table_handle,
                                coord_origin, coord_delta, N_interp_points,
                                CCTK_VARIABLE_REAL,
                                (const void *const *) interp_coords,
@@ -295,6 +297,7 @@ static void *RefineData (CCTK_INT input_dims[2], const void *input_data)
   }
 
   free (interp_coords[0]);
+  Util_TableDestroy (table_handle);
 
   return (refined_data);
 }