Changeset 15176

Timestamp:

Oct 3, 2007, 10:21:45 AM (19 years ago)

Author:

Paul Price

Message:

Renaming fits->compression to fits->compConvention to distinguish between compression and compresion convention. Reworking psFitsMoveExtName, essentially using p_psFitsMoveExtName_UserKey as psFitsMoveExtName: Files compressed with cfitsio's 'imcopy' program may have multiple EXTNAME keywords, with the first set to COMPRESSED_IMAGE. However, fits_movnam_hdu won't find the second (proper) value of EXTNAME, and so can fail to find a perfectly legitimate extension, simply because imcopy does something silly. However, we really want to be able to read these files (MegaCam data are shipped as imcopy-compressed images). Therefore, we implement our own version of moving to an extension specified by name. The pure cfitsio version (what was originally in psFitsMoveExtName) is used if 'compConvention' handling is turned off in the psFits structure.

Location:

branches/pap_branch_070920/psLib/src/fits

Files:

• psFits.c (modified) (5 diffs)
• psFits.h (modified) (2 diffs)

branches/pap_branch_070920/psLib/src/fits/psFits.c

@@ -7 +7 @@
  *  @author Robert DeSonia, MHPCC
  *
- *  @version $Revision: 1.71.2.3 $ $Name: not supported by cvs2svn $
- *  @date $Date: 2007-10-03 03:01:45 $
+ *  @version $Revision: 1.71.2.4 $ $Name: not supported by cvs2svn $
+ *  @date $Date: 2007-10-03 20:21:45 $
  *
  *  Copyright 2004-2005 Maui High Performance Computing Center, University of Hawaii
@@ -20 +20 @@
 
 #include "psFits.h"
+#include "psFitsHeader.h"
 #include "string.h"
 #include "psError.h"
@@ -161 +162 @@
     fits->writable = (iomode == READWRITE);
     fits->extword = NULL;
-    fits->compression = true;
+    fits->compConvention = true;
     psMemSetDeallocator(fits,(psFreeFunc)fitsFree);
 
@@ -232 +233 @@
 }
 
-// move to the first HDU where extword == extname.  this is equivalent to fits_movnam_hdu() for
-// a user-defined word in place of EXTNAME
-bool p_psFitsMoveExtName_UserKey(const psFits *fits,
-                                 const char *extname,
-                                 const char *extword)
-{
-    PS_ASSERT_FITS_NON_NULL(fits,   false);
-    PS_ASSERT_PTR_NON_NULL(extname, false);
-    PS_ASSERT_PTR_NON_NULL(extword, false);
-
-    int hdutype = 0;
-    char name[MAX_STRING_LENGTH];
-    char extstring[MAX_STRING_LENGTH];
-
-    sprintf (extstring, "'%s'", extname);
-
-    // NOTE: fits_* return 0 for success
-    for (int i = 1; true; i++) {
-        // are we able to read the next HDU?
-
-        int status = 0;
-        if (fits_movabs_hdu(fits->fd, i, &hdutype, &status)) {
-            char fitsErr[MAX_STRING_LENGTH];
-            fits_get_errstatus(status, fitsErr);
-            psError(PS_ERR_LOCATION_INVALID, true,
-                    _("Could not find HDU with %s = '%s'. CFITSIO Error: %s"),
-                    extword, extname, fitsErr);
-            return false;
-        }
-        // is there a keyword called 'extword'? (read as string regardless of type)
-        status = 0;
-        if (fits_read_keyword(fits->fd, (char *)extword, name, NULL, &status)) {
-            continue;
-        }
-        // if this was read as a string, we will have leading and trailing single-quotes
-        // try both for comparison
-
-        // do we have the right hdu (names match)?
-        if (!strcmp (name, extname) || !strcmp (name, extstring)) {
-            return true;
-        }
-    }
-    psAbort("we should not reach here");
-}
-
-// XXX I will need to define a low-level function p_psFitsMoveExtName_UserKey () which
-// uses fits_movabs_hdu() to replicate the functionality of fits_movnam_hdu using an
-// alternate name for EXTNAME
+// Files compressed with cfitsio's "imcopy" program may have multiple EXTNAME keywords, with the first set to
+// COMPRESSED_IMAGE.  However, fits_movnam_hdu won't find the second (proper) value of EXTNAME, and so can
+// fail to find a perfectly legitimate extension, simply because imcopy does something silly.  However, we
+// really want to be able to read these files (MegaCam data are shipped as imcopy-compressed images).
+// Therefore, we implement our own version of moving to an extension specified by name.  The pure cfitsio
+// version is used if "compConvention" handling is turned off in the psFits structure.
 bool psFitsMoveExtName(const psFits* fits,
                        const char* extname)
@@ -288 +247 @@
     int status = 0;
 
-    if (fits->extword != NULL) {
-        bool result = p_psFitsMoveExtName_UserKey(fits, extname, fits->extword);
-        return (result);
-    }
-
-    if (fits_movnam_hdu(fits->fd, ANY_HDU, (char*)extname, 0, &status) != 0) {
-        char fitsErr[MAX_STRING_LENGTH];
-        fits_get_errstatus(status, fitsErr);
-        psError(PS_ERR_LOCATION_INVALID, true,
-                _("Could not find HDU '%s'. CFITSIO Error: %s"),
-                extname, fitsErr);
-        return false;
-    }
-
-    return true;
+    if (!fits->compConvention && !fits->extword) {
+        // User wants to use cfitsio.  Good luck to them!
+        if (fits_movnam_hdu(fits->fd, ANY_HDU, (char*)extname, 0, &status) != 0) {
+            psFitsError(status, true, _("Could not find HDU '%s'"), extname);
+            return false;
+        }
+        return true;
+    }
+
+    bool ignoreCI = (fits->compConvention &&
+                     (strcmp(extname, "COMPRESSED_IMAGE") != 0)); // Ignore COMPRESSED_IMAGE extension name?
+    char *extword = (fits->extword ? fits->extword : "EXTNAME"); // Word to use as extension name
+
+#if 0
+    // XXX Future optimisation: loop through from the current HDU to the end, then from the start to the
+    // current position.  This will save seeking through the file multiple times.
+    int currentExt = psFitsGetExtNum(fits); // Current extension number
+    int numExt = psFitsGetSize(fits);   // Total number of extensions
+#endif
+
+    for (int i = 1; true; i++) {
+        int hdutype = 0;
+        if (fits_movabs_hdu(fits->fd, i, &hdutype, &status)) {
+            // We've run off the end
+            psFitsError(status, true, _("Could not find HDU with %s = '%s'"), extword, extname);
+            return false;
+        }
+        // Is there a keyword called 'extword'? (read as string regardless of type)
+        char name[MAX_STRING_LENGTH];  // Name of extension
+        if (fits_read_keyword(fits->fd, extword, name, NULL, &status)) {
+            // It doesn't exist in the header.
+            // This isn't the extension you're looking for.  Move along.
+            status = 0;
+            continue;
+        }
+        char *fixed = p_psFitsHeaderParseString(name); // Parsed version (removing quotes and spaces)
+
+        if (ignoreCI && strcmp(fixed, "COMPRESSED_IMAGE") == 0) {
+            // Read it again, Sam
+            if (fits_read_keyword(fits->fd, extword, name, NULL, &status)) {
+                status = 0;
+                continue;
+            }
+            fixed = p_psFitsHeaderParseString(name);
+        }
+
+        if (strcmp(fixed, extname) == 0) {
+            // We've arrived
+            return true;
+        }
+    }
+    psAbort("Should never reach here.");
 }
 

branches/pap_branch_070920/psLib/src/fits/psFits.h

@@ -4 +4 @@
  * @author Robert DeSonia, MHPCC
  *
- * @version $Revision: 1.31.2.3 $ $Name: not supported by cvs2svn $
- * @date $Date: 2007-10-03 03:01:45 $
+ * @version $Revision: 1.31.2.4 $ $Name: not supported by cvs2svn $
+ * @date $Date: 2007-10-03 20:21:45 $
  * Copyright 2004-2005 Maui High Performance Computing Center, University of Hawaii
  */
@@ -55 +55 @@
     bool writable;                      ///< Is the file writable?
     char *extword;                      ///< user-specified word to name extensions (NULL implies EXTNAME)
-    bool compression;                   ///< Treat compressed images automatically?
+    bool compConvention;                ///< Honour compression convention, handling compressed images
 } psFits;