ENH: Support several types of derived datasets, all declared in one p…

…lace

gdal/frmts/cderived/cderiveddataset.cpp

@@ -1,10 +1,10 @@
 #include "../vrt/vrtdataset.h"
 #include "gdal_pam.h"
 #include "gdal_proxy.h"
+#include "derivedlist.h"
 
 #include <iostream>
 
-
 class ComplexDerivedDatasetContainer: public GDALPamDataset
 {
     public:
@@ -19,7 +19,6 @@ class ComplexDerivedDataset : public VRTDataset
   ~ComplexDerivedDataset();
 
     static GDALDataset *Open( GDALOpenInfo * );
-    static int          Identify( GDALOpenInfo * );
 };
 
 
@@ -33,26 +32,11 @@ ComplexDerivedDataset::~ComplexDerivedDataset()
 {
 }
 
-int ComplexDerivedDataset::Identify(GDALOpenInfo * poOpenInfo)
-{
-  if(STARTS_WITH_CI(poOpenInfo->pszFilename, "DERIVED_SUBDATASET:COMPLEX_AMPLITUDE:"))
-    return TRUE;
-
-  return FALSE;
-}
-
 GDALDataset * ComplexDerivedDataset::Open(GDALOpenInfo * poOpenInfo)
-{ 
-  if( !Identify(poOpenInfo) )
-    {
-    return NULL;
-    }
-
+{
   /* Try to open original dataset */
   CPLString filename(poOpenInfo->pszFilename);
-
-  // TODO: check starts with
-
+
   /* DERIVED_SUBDATASET should be first domain */
   size_t dsds_pos = filename.find("DERIVED_SUBDATASET:");
 
@@ -62,14 +46,35 @@ GDALDataset * ComplexDerivedDataset::Open(GDALOpenInfo * poOpenInfo)
     return NULL;
     }
 
-  /* DERIVED_SUBDATASET should be first domain */
+  /* Next, we need to now which derived dataset to compute */
   size_t alg_pos = filename.find(":",dsds_pos+20);
   if (alg_pos == std::string::npos)
     {
-    /* Unable to Open in this case */
+    /* Unable to Open if we do not find the name of the derived dataset */
     return NULL;
     }
-
+
+  CPLString odDerivedName = filename.substr(dsds_pos+19,alg_pos-dsds_pos-19);
+
+  CPLDebug("ComplexDerivedDataset::Open","Derived dataset identified: %s",odDerivedName.c_str());
+
+  CPLString pixelFunctionName = "";
+  bool datasetFound = false;
+
+  for(unsigned int derivedId = 0; derivedId<NB_DERIVED_DATASETS;++derivedId)
+    {
+    if(odDerivedName == asDDSDesc[derivedId].pszDatasetName)
+      {
+      datasetFound = true;
+      pixelFunctionName = asDDSDesc[derivedId].pszPixelFunction;
+      }
+    }
+
+  if(!datasetFound)
+    {
+    return NULL;
+    }
+
   CPLString odFilename = filename.substr(alg_pos+1,filename.size() - alg_pos);
 
   GDALDataset * poTmpDS = (GDALDataset*)GDALOpen(odFilename, GA_ReadOnly);

gdal/frmts/cderived/derivedlist.h

@@ -0,0 +1,25 @@
+#ifndef DERIVEDLIST_H_INCLUDEd
+#define DERIVEDLIST_H_INCLUDEd
+
+typedef struct
+{
+  const char * pszDatasetName;
+  const char * pszDatasetDescritpion;
+  const char * pszPixelFunction;
+} DerivedDatasetDescription;
+
+static const DerivedDatasetDescription asDDSDesc [] =
+{
+  { "AMPLITUDE", "Amplitude of input bands", "mod"},
+  { "PHASE", "Phase of input bands", "phase"},
+  { "REAL", "Real part of input bands", "real"},
+  { "IMAG", "Imaginary part of input bands", "imag"},
+  { "CONJ", "Conjugate of input bands", "conj"},
+  { "INTENSITY", "Intensity (squared amplitude) of input bands", "intensity"},
+  { "LOGAMPLITUDE", "log10 of amplitude of input bands", "log10"}
+};
+
+#define NB_DERIVED_DATASETS (sizeof(asDDSDesc)/sizeof(asDDSDesc[0]))
+
+
+#endif

gdal/gcore/gdaldataset.cpp

@@ -40,6 +40,7 @@
 #include "ograpispy.h"
 #include "ogrunionlayer.h"
 #include "swq.h"
+#include "../frmts/cderived/derivedlist.h"
 
 #ifdef SQLITE_ENABLED
 #include "../sqlite/ogrsqliteexecutesql.h"
@@ -3305,13 +3306,19 @@ char ** GDALDataset::GetMetadata(const char * pszDomain)
     {
     papoDerivedMetadataList->Clear();
 
+
+
     // First condition: at least one raster band
     if(GetRasterCount()>0)
       {
-      papoDerivedMetadataList->SetNameValue("DERIVED_SUBDATASET_1_NAME",CPLSPrintf("DERIVED_SUBDATASET:COMPLEX_AMPLITUDE:%s",GetDescription()));
-
-      CPLString osDesc(CPLSPrintf("Complex amplitude of bands from %s",GetDescription()));
-      papoDerivedMetadataList->SetNameValue("DERIVED_SUBDATASET_1_DESC",osDesc.c_str());
+      CPLDebug("GDALDataset::GetMetadata","Number of derived datasets to report: %i",(int)NB_DERIVED_DATASETS);
+        for(unsigned int derivedId = 0; derivedId<NB_DERIVED_DATASETS;++derivedId)
+          {          
+          papoDerivedMetadataList->SetNameValue(CPLSPrintf("DERIVED_SUBDATASET_%i_NAME",derivedId),CPLSPrintf("DERIVED_SUBDATASET:%s:%s",asDDSDesc[derivedId].pszDatasetName,GetDescription()));
+
+          CPLString osDesc(CPLSPrintf("%s from %s",asDDSDesc[derivedId].pszDatasetDescritpion,GetDescription()));
+          papoDerivedMetadataList->SetNameValue(CPLSPrintf("DERIVED_SUBDATASET_%i_DESC",derivedId),osDesc.c_str());
+          }
       }
 
     return papoDerivedMetadataList->List();