Index: trunk/psModules/src/objects/pmModelClass.c
===================================================================
--- trunk/psModules/src/objects/pmModelClass.c	(revision 34259)
+++ trunk/psModules/src/objects/pmModelClass.c	(revision 36441)
@@ -66,4 +66,5 @@
 
 static pmModelClass *models = NULL;
+static psVector *modelClassLookupTable = NULL;  // translation between model types in header and here
 static int Nmodels = 0;
 
@@ -135,4 +136,6 @@
     models = NULL;
     Nmodels = 0;
+    psFree(modelClassLookupTable);
+    modelClassLookupTable = NULL;
     return;
 }
@@ -193,2 +196,80 @@
 }
 
+
+bool pmModelClassWriteHeader(psMetadata *header)
+{
+    psMetadataAddS32(header, PS_LIST_TAIL, "MTNUM", PS_META_REPLACE, "number of model types", Nmodels);
+    for (int i = 0; i < Nmodels; i++) {
+        char modelNameKey[16];
+        char modelValKey[16];
+        sprintf(modelNameKey, "MTNAM%02d", i);
+        sprintf(modelValKey,  "MTVAL%02d", i);
+        psMetadataAddStr(header, PS_LIST_TAIL, modelNameKey, PS_META_REPLACE, "", models[i].name);
+        psMetadataAddS32(header, PS_LIST_TAIL, modelValKey, PS_META_REPLACE, "", i);
+    }
+
+    return true;
+}
+
+bool pmModelClassReadHeader(psMetadata *header) {
+    psFree(modelClassLookupTable);
+
+    bool status;
+    int numHeaderModels = psMetadataLookupS32(&status, header, "MTNUM");
+    if (!status) {
+        return false;
+    }
+
+    psVector *inputTypes = psVectorAlloc(numHeaderModels, PS_TYPE_S32);
+    psVector *localTypes = psVectorAlloc(numHeaderModels, PS_TYPE_S32);
+    int max_val = -1;
+    for (int i = 0; i < numHeaderModels; i++) {
+        char modelNameKey[16];
+        char modelValKey[16];
+        sprintf(modelNameKey, "MTNAM%02d", i);
+        sprintf(modelValKey,  "MTVAL%02d", i);
+        psString thisName = psMetadataLookupStr(&status, header, modelNameKey);
+        int thisVal = psMetadataLookupS32(&status, header, modelValKey);
+        if (thisVal > max_val) {
+            max_val = thisVal;
+        }
+        inputTypes->data.S32[i] = thisVal;
+        localTypes->data.S32[i] = pmModelClassGetType(thisName);
+    }
+    if (max_val < 0) {
+        psFree(inputTypes);
+        psFree(localTypes);
+        return false;
+    }
+
+    modelClassLookupTable = psVectorAlloc(max_val + 1, PS_TYPE_S32);
+    psVectorInit(modelClassLookupTable, -1);
+
+    for (int i = 0; i < numHeaderModels; i++) {
+        int thisVal = inputTypes->data.S32[i];
+        int localVal = localTypes->data.S32[i];
+        modelClassLookupTable->data.S32[thisVal] = localVal;
+    }
+    psFree(inputTypes);
+    psFree(localTypes);
+
+    return true;
+}
+
+pmModelType pmModelClassGetLocalType(pmModelType inputType) {
+    pmModelType localType = -1;
+
+    if (modelClassLookupTable) {
+        if (inputType >= 0 && inputType < modelClassLookupTable->n) {
+            localType = modelClassLookupTable->data.S32[inputType];
+        }
+    } else {
+        // no lookup table defined
+        // for backwards compatability if inputType refers to a defined model, return it
+        if (inputType >= 0 && pmModelClassGetName(inputType)) {
+            localType = inputType;
+        }
+    }
+
+    return localType;
+}