Changeset 13039 for trunk/Ohana/src/libfits/matrix/F_read_segment.c

Timestamp:

Apr 25, 2007, 4:18:23 PM (19 years ago)

Author:

eugene

Message:

convert gfits_read_segment to gfits_read_matrix_segment; add gfits_fread_matrix_segment

File:

• trunk/Ohana/src/libfits/matrix/F_read_segment.c (modified) (5 diffs)

trunk/Ohana/src/libfits/matrix/F_read_segment.c

@@ -2 +2 @@
 # include <gfitsio.h>
 
-/** warning: this function requires 'dparse' which is included in libohana.a **/
-int dparse (double *, int, char *region);
-
 /*********************** fits read matrix ***********************************/
-int gfits_read_segment (char *filename, Matrix *matrix, char *region) {
+int gfits_read_matrix_segment (char *filename, Matrix *matrix, char *region) {
 
   FILE *f;
   Header header;
+  int status;
+
+  f = fopen (filename, "r");
+  if (f == NULL) {
+    return (FALSE);
+  }
+
+  status = gfits_fread_header (f, &header);
+  if (!status) {
+    fclose (f);
+    fprintf (stderr, "error reading header of FITS file %s\n", filename);
+    return (FALSE);
+  }
+
+  status = gfits_fread_matrix_segment (f, matrix, &header, region);
+  if (!status) {
+    fclose (f);
+    fprintf (stderr, "error reading header of FITS file %s\n", filename);
+    return (FALSE);
+  }
+
+  fclose (f);
+  return (TRUE);
+}
+
+// read header before calling this function
+// file pointer should be at start of Matrix data segment
+int gfits_fread_matrix_segment (FILE *f, Matrix *matrix, Header *header, char *region) {
+
   int status, i, nbytes, Nbytes, Nskip, NbytesData;
   int wantaxis[FT_MAX_NAXES][2];
@@ -16 +42 @@
   int perpix;
 
-  status = gfits_read_header (filename, &header);
-  if (!status) {
-    fprintf (stderr, "error reading header of FITS file %s\n", filename);
-    return (FALSE);
-  }
-
-  f = fopen (filename, "r");
-  if (f == NULL) {
-    return (FALSE);
-  }
-
   for (i = 0; i < FT_MAX_NAXES; i++) {
     wantaxis[i][0] = wantaxis[i][1] = 0;
   }
 
-  for (i = 0; i < header.Naxes; i++) {
+  for (i = 0; i < header[0].Naxes; i++) {
     status = dparse (&tmp, 2*i + 1, region);
     if (!status || (tmp < 0))
       wantaxis[i][0] = 0;
     else 
-      wantaxis[i][0] = (tmp > header.Naxis[i] - 1) ? header.Naxis[i] - 1 : tmp;
+      wantaxis[i][0] = (tmp > header[0].Naxis[i] - 1) ? header[0].Naxis[i] - 1 : tmp;
     status = dparse (&tmp, 2*i + 2, region);
     if (!status || (tmp < 0))
-      wantaxis[i][1] = header.Naxis[i];
+      wantaxis[i][1] = header[0].Naxis[i];
     else 
-      wantaxis[i][1] = (tmp > header.Naxis[i]) ? header.Naxis[i] : tmp;
+      wantaxis[i][1] = (tmp > header[0].Naxis[i]) ? header[0].Naxis[i] : tmp;
   }
 
-  fseek (f, header.size, 0);
-
-  matrix[0].bitpix = header.bitpix;
-  matrix[0].unsign = header.unsign;
-  matrix[0].bscale = header.bscale;
-  matrix[0].bzero  = header.bzero;
-  matrix[0].Naxes  = header.Naxes;
+  matrix[0].bitpix = header[0].bitpix;
+  matrix[0].unsign = header[0].unsign;
+  matrix[0].bscale = header[0].bscale;
+  matrix[0].bzero  = header[0].bzero;
+  matrix[0].Naxes  = header[0].Naxes;
   for (i = 0; i < FT_MAX_NAXES; i++)
     matrix[0].Naxis[i] = wantaxis[i][1] - wantaxis[i][0];
@@ -76 +89 @@
   /* currently only good for reading in full planes in 3-D */
   fseek (f, Nskip, SEEK_CUR);
-
   nbytes = fread (matrix[0].buffer, sizeof(char), Nbytes, f);
-  fclose (f);
   matrix[0].size = Nbytes;
 
 # ifdef BYTE_SWAP  
-  perpix = abs(header.bitpix) / 8;
+  perpix = abs(header[0].bitpix) / 8;
   if (perpix > 1) {
     byte0 = (unsigned char *) matrix[0].buffer;
@@ -128 +139 @@
 # endif
 
-  gfits_free_header (&header);
-
   if (nbytes < Nbytes - 2880) {  /* this is a bad FITS error: image is not OK */
-    fprintf (stderr, "error reading in matrix data from FITS file %s (%d < %d - 2880)\n", filename, nbytes, Nbytes);
+    fprintf (stderr, "error reading in matrix data from FITS file (%d < %d - 2880)\n", nbytes, Nbytes);
     return (FALSE);
   }
   if (nbytes != Nbytes) {  /* this is a FITS error, but often the image is OK */
-    fprintf (stderr, "incomplete block in %s: (%d, %d)\n", filename, nbytes, Nbytes);
+    fprintf (stderr, "incomplete block in FITS file: (%d, %d)\n", nbytes, Nbytes);
     return (TRUE); 
   }
@@ -142 +151 @@
 
 }
-