L_BarCodeGetFirstDuplicated

#include "ltbar.h"

L_LTBAR_API L_INT L_BarCodeGetFirstDuplicated(pBarCodeData, nIndex)

Returns the index of the first barcode in the array that is a duplicate of the barcode at index nIndex.

Returns

Comments

LEADTOOLS provides a number of functions to let you work with duplicated barcodes. They let you:

• Find the number of duplicates of a specific barcode

• Determine whether a specific barcode is duplicated

• Get the index of the first duplicated barcode

• Get the index of a subsequent barcode

To determine whether a barcode is duplicated, use the L_BarCodeIsDuplicated function. If a barcode is duplicated, L_BarCodeGetDuplicated will return the index of the first barcode in the array after the specified barcode, which is a duplicate of the specified barcode.

If you know the index of a barcode within an array, you can get the index of the first duplicate of the specified barcode using L_BarCodeGetFirstDuplicated. Use the L_BarCodeGetNextDuplicated to get the next instance of a duplicated barcode.

Although no function is included to tell you the number of different sets of barcodes that are duplicated, you can easily program this by using the following code:

L_INT i, j, nCount;
L_BOOL * pbVisited = (L_BOOL *)malloc(pBarCodeData->nTotalCount*sizeof(L_BOOL));
memset(pbVisited, 0, pBarCodeData->nTotalCount*sizeof(L_BOOL));
nCount = 0;
for (i=0; i<pBarCodeData->nTotalCount; i++)
{
if(pbVisited[i])
continue;
pbVisited[i] = TRUE;
nCount++;
j = i;
while(pBarCodeData[j].nIndexDuplicate != -1)
{
j = pBarCodeData[j].nIndexDuplicate;
pbVisited[j] = TRUE;
}
}
free(pbVisited);

After this code is executed, nCount will contain the number of different sets of barcodes.

As an example, suppose you have a call to L_BarCodeRead that reads ten barcodes into a BARCODEDATA array. When L_BarCodeIsDuplicated is called for the item at index 3 in the array TRUE is returned. Therefore one or more barcodes in the array are duplicates of the specified item.

Calling L_BarCodeGetFirstDuplicated returns the index of the first barcode in the array that is a duplicate of the barcode at index 3 in the array. Suppose this value is 0. The barcode present at index zero in the array is the first duplicate of the barcode at index 3.

Calling L_BarCodeGetNextDuplicated with nIndex set to 3 will return the index of the next barcode in the array that is a duplicate of the barcodes at index 0 and 3. Suppose this value is 9. Therefore the barcodes at index 0, index 3, and index 9 of the array are all duplicates.

Required DLLs and Libraries

Platforms

Win32, x64, Mobile

See Also

Example

For complete sample code refer to MFCBar32 demo.

L_INT BarCodeGetFirstDuplicatedExample(HWND hWnd, pBARCODEDATA * ppBarCodeData)
{
   L_INT nDupIndex=0;
   L_TCHAR szBuffer[256];
   if (!ppBarCodeData) 
      return FAILURE;
   ZeroMemory(szBuffer, sizeof(szBuffer));
   // suppose you have more than 5 in ppBarCodeData of BARCODEDATA
   if (L_BarCodeIsDuplicated(&(*ppBarCodeData)[1]))
   {
      nDupIndex = L_BarCodeGetFirstDuplicated(*ppBarCodeData, 1);
      if (nDupIndex >= 0)
      {
         // Print the first duplicated bar code data
         wsprintf(szBuffer, TEXT("Data is %hs\nType %d\nUnits %d\nPosX %d\nPosY %d\nWidth %d\nHeight %d\n\n"),
                  (*ppBarCodeData)[nDupIndex].pszBarCodeData, (*ppBarCodeData)[nDupIndex].ulType, (*ppBarCodeData)[nDupIndex].nUnits, 
                  (*ppBarCodeData)[nDupIndex].rcBarLocation.left,
                  (*ppBarCodeData)[nDupIndex].rcBarLocation.top,
                  abs((*ppBarCodeData)[nDupIndex].rcBarLocation.right - (*ppBarCodeData)[nDupIndex].rcBarLocation.left),
                  abs((*ppBarCodeData)[nDupIndex].rcBarLocation.bottom - (*ppBarCodeData)[nDupIndex].rcBarLocation.top));
         return SUCCESS;
      }
      else
      {
         wsprintf(szBuffer, TEXT("An error occurred in L_BarCodeGetFirstDuplicated\nError Code = %d\n"), nDupIndex);
         return nDupIndex;
      }
   }
   else
      wsprintf(szBuffer, TEXT("This Bar Code does not duplicated ..."));
   MessageBox(hWnd, szBuffer, ((nDupIndex >= 0) ? TEXT("BarCode Info.") : TEXT("Notice!")), MB_OK);
   return SUCCESS;
}