resaseda [FEATURE]: provide shrink option

a new option for resaseda provides the shrink option in the resample function
of the interpolator

src/ts/wf/resaseda.cc

@@ -4,11 +4,11 @@
  * ----------------------------------------------------------------------------
  * 
  * \author Thomas Forbriger
- * \date 13/07/2005
+ * \date 07/11/2017
  * 
  * resample seismic data
  * 
- * Copyright (c) 2005 by Thomas Forbriger (BFO Schiltach) 
+ * Copyright (c) 2005, 2017 by Thomas Forbriger (BFO Schiltach) 
  *
  * ----
  * RESASEDA is free software; you can redistribute it and/or modify
@@ -34,11 +34,12 @@
  *  - 03/08/2011   V1.3   implement delay option
  *  - 14/09/2011   V1.4   implement sample offset windows
  *  - 21/11/2012   V1.5   provide different output formats
+ *  - 07/11/2017   V1.6   provide option shrink
  * 
  * ============================================================================
  */
 #define RESASEDA_VERSION \
-  "RESASEDA   V1.5   resample seismic data"
+  "RESASEDA   V1.6   resample seismic data"
 
 #include <fstream>
 #include <iostream>
@@ -61,7 +62,7 @@ using libtime::TAbsoluteTime;
 using libtime::TRelativeTime;
 
 struct Options {
-  bool verbose, overwrite, debug, delay;
+  bool verbose, overwrite, debug, delay, shrink;
   bool timefirstset, timelastset, timespanset, dtset, nset;
   TAbsoluteTime timefirst, timelast;
   TRelativeTime timespan, edge;
@@ -85,7 +86,7 @@ int main(int iargc, char* argv[])
     "usage: resaseda [-tf time] [-tl time] [-n n] [-dt dt] [-ts time]" "\n"
     "                [-v] [-o] [-sf time] [-sl time] [-edge s]" "\n"
     "                [-delay d] [-type type] [-Type type]\n"
-    "                [-sof n] [-sol n]" "\n"
+    "                [-sof n] [-sol n] [-shrink]" "\n"
     "                outfile infile [t:T] [infile [t:T] ...]" "\n"
     "   or: resaseda --help|-h" "\n"
     "   or: resaseda --xhelp" "\n"
@@ -122,6 +123,11 @@ int main(int iargc, char* argv[])
     "-sol n       define last sample index by offset n\n"
     "               positive sample index: define by offset from last sample\n"
     "               negative sample index: define by offset from first sample\n"
+    "-shrink      if defined output time window is larger than time span\n"
+    "               for which input data is available, reduce output time\n"
+    "               window approrpiate for each input trace while maintaining\n"
+    "               the defined ѕampling raster (useful for input data\n"
+    "               containing gaps)\n"
   };
 
   // define commandline options
@@ -164,6 +170,8 @@ int main(int iargc, char* argv[])
     {"Type",arg_yes,"sff"},
     // 17: extended help
     {"xhelp",arg_no,"-"},
+    // 18: use shrink option with resample function
+    {"shrink",arg_no,"-"},
     {NULL}
   };
 
@@ -233,6 +241,7 @@ int main(int iargc, char* argv[])
   opt.sampleoffsetbegin=cmdline.int_arg(14);
   opt.sampleoffsetend=cmdline.int_arg(15);
   opt.outputformat=cmdline.string_arg(16);
+  opt.shrink=cmdline.optset(18);
     
   // check options consistency
   {
@@ -425,6 +434,14 @@ int main(int iargc, char* argv[])
                  << "      prior to resampling!"
                  << endl;
           }
+          if (opt.shrink)
+          {
+            cout << "    shrink output time window to available input" <<
+              endl
+                 << "      data while maintaining the defined sampling" <<
+              endl
+                 << "      raster" << endl;
+          }
         }
         
         // go for interpolation
@@ -455,15 +472,31 @@ int main(int iargc, char* argv[])
         bool hot=true;
         try
         {
-          outseries=ts::ipo::resample(*hipo, firstsample, newdt, nsamples);
+          outseries=ts::ipo::resample(*hipo, firstsample, newdt, nsamples,
+                                      opt.shrink);
         }
         catch (ts::ipo::ExceptionTimeWindowOutside)
         {
           cout << "NOTICE: skipping this trace silently..." << endl;
           hot=false;
         }
+        catch (ts::ipo::ExceptionTimeWindowEmpty)
+        {
+          cout << "NOTICE: skipping this trace silently..." << endl;
+          hot=false;
+        }
         if (hot)
         {
+          if (opt.shrink && opt.verbose)
+          {
+            cout << "  time window returned from interpolator:" << endl
+              <<    "                begin: "
+              << outseries.header.date.timestring() << endl
+              <<    "                  end: " 
+              << sff::wid2lastsample(outseries.header).timestring() << endl
+              <<    "    number of samples: " 
+              << outseries.header.nsamples << endl;
+          }
           TFXX_debug(opt.debug, "main", 
                      "  series is resampled");
           os << outseries.header;