LVParseTree Summary

 A ParseTree represents a sentence diagram of SRE output, according to the SRGS grammar that was matched.  Information about the tree is accessed through iterators.

The function call LVCA_GetParseTreeHandle retrieves a pointer of type H_PARSE_TREE.  

BOOL LVCA_GetParseTreeHandle(HANDLE hCA, LONG ParseIndex, void ** Tree) ;

All functions using the H_PARSE_TREE can be found in the header <LV_SRE_ParseTree.h>.  The help documentation can be found in the LumenVox Speech Rec API help document.

Cast the void pointer to a H_PARSE_TREE Variable Type.

void* Tree;

LONG count;

LVCA_GetNumberOfSRGSParses(hCA, &count);

for(int i = 0; i < count; i++)

{

LVCA_GetParseTreeHandle(hCA, 1, tree)

H_PARSE_TREE ptree = (H_PARSE_TREE) Tree

PrintTags(ptree);

PrintTree(ptree);

LVParseTree_Release(ptree);

}

For the examples below the active grammar will be:

#ABNF 1.0;
language en-US;
mode voice;
tag-format <XML>; //a made up tag format.

root $PhoneNumber;

$Digit = one {1} | two {2} | three {3} | four {4} | five {5} |
         six {6} | seven {7} | eight {8} | nine {9} | (zero | oh) {0};         

$AreaCode = [area code | one] {<AREA_CODE>} $Digit<3> {</AREA_CODE>};

$PhoneNumber = [$AreaCode] {<PHONE>} $Digit<7> {</PHONE>};

And the decoded sentence will be "area code eight five eight seven oh seven oh seven oh seven"

Example 1

void PrintTags(H_PARSE_TREE Tree)

{

H_PARSE_TREE_NODE N;

H_PARSE_TREE_ITR Itr;

char buffer[1024];

Itr = LVParseTree_CreateIteratorBegin(Tree);

for (; !LVParseTree_Iterator_IsPastEnd(Itr); LVParseTree_Iterator_Advance(Itr))

{

N = LVParseTree_Iterator_GetNode(Itr);

if(LVParseTree_Node_IsTag(N))

{

printf("%s ", LVParseTree_Node_GetLabel(N));

}

}

LVParseTree_Iterator_Release(Itr);

}

Example 1 result:

"<AREA_CODE> 8 5 8 </AREA_CODE> <PHONE> 7 0 7 0 7 0 7 </PHONE>"

Example 2

void PrintNode(H_PARSE_TREE_NODE N)

{
     H_PARSE_TREE_CHILDREN_ITR I;
     int i;

     for (i = 0; i < LVParseTree_Node_GetLevel(N); ++i)
          printf("     ");
     
     if (LVParseTree_Node_IsTerminal(N))
          printf("\"%s\"\n",LVParseTree_Node_GetText(N));
     if (LVParseTree_Node_IsTag(N))
          printf("{ %s }\n",LVParseTree_Node_GetText(N));
     if (LVParseTree_Node_IsRule(N))
     {
          printf("$%s:\n",LVParseTree_Node_GetRuleName(N));
          I = LVParseTree_Node_CreateChildrenIterator(N);

          while (!LVParseTree_ChildrenIterator_IsPastEnd(I))
          {
               PrintNode(LVParseTree_ChildrenIterator_GetNode(I));
               LVParseTree_ChildrenIterator_Advance(I);
          }
          LVParseTree_ChildrenIterator_Release(I);
     }
}


void PrintTree(H_PARSE_TREE Tree)
{
     PrintNode(LVParseTree_GetRoot(Tree));
}

Example 2 Result

$PhoneNumber:
     $AreaCode:
          "AREA"
          "CODE"
          { <AREA_CODE> }
          $Digit:
               "EIGHT"
               { 8 }
          $Digit:
               "FIVE"
               { 5 }
          $Digit:
               "EIGHT"
               { 8 }
          { </AREA_CODE> }
     { <PHONE> }
     $Digit:
          "SEVEN"
          { 7 }
     $Digit:
          "OH"
          { 0 }
     $Digit:
          "SEVEN"
          { 7 }
     $Digit:
          "OH"
          { 0 }
     $Digit:
          "SEVEN"
          { 7 }
     $Digit:
          "OH"
          { 0 }
     $Digit:
          "SEVEN"
          { 7 }
     { </PHONE> }

Additional Information

LumenVox Speech Rec API

LVParseTree C API Functions

LVParseTree_Node C API

Complete Help Topic List | Speech Platform Product Information