dmtxsymbol.c

/**
 * libdmtx - Data Matrix Encoding/Decoding Library
 * Copyright 2008, 2009 Mike Laughton. All rights reserved.
 * Copyright 2012-2016 Vadim A. Misbakh-Soloviov. All rights reserved.
 * Copyright 2016 Tim Zaman. All rights reserved.
 *
 * See LICENSE file in the main project directory for full
 * terms of use and distribution.
 *
 * Contact:
 * Vadim A. Misbakh-Soloviov <dmtx@mva.name>
 * Mike Laughton <mike@dragonflylogic.com>
 *
 * \file dmtxsymbol.c
 * \brief Data Matrix symbol attributes
 */


/**
 * \brief  Retrieve symbol index from rows and columns
 * \param  rows
 * \param  cols
 * \return sizeIdx value
 */
extern int 
getSizeIdxFromSymbolDimension(int rows, int cols)
{
  int symbolRows, symbolCols;
  for (int i=0; i<30; i++){
    symbolRows = dmtxGetSymbolAttribute(DmtxSymAttribSymbolRows, i);
    symbolCols = dmtxGetSymbolAttribute(DmtxSymAttribSymbolCols, i);
    if (rows==symbolRows && cols==symbolCols){
      return i;
    }
  }
  return -1;
}


/**
 * \brief  Retrieve property based on symbol size
 * \param  attribute
 * \param  sizeIdx
 * \return Attribute value
 */
extern int
dmtxGetSymbolAttribute(int attribute, int sizeIdx)
{
   static const int symbolRows[] = { 10, 12, 14, 16, 18, 20,  22,  24,  26,
                                                 32, 36, 40,  44,  48,  52,
                                                 64, 72, 80,  88,  96, 104,
                                                        120, 132, 144,
                                                  8,  8, 12,  12,  16,  16 };

   static const int symbolCols[] = { 10, 12, 14, 16, 18, 20,  22,  24,  26,
                                                 32, 36, 40,  44,  48,  52,
                                                 64, 72, 80,  88,  96, 104,
                                                        120, 132, 144,
                                                 18, 32, 26,  36,  36,  48 };

   static const int dataRegionRows[] = { 8, 10, 12, 14, 16, 18, 20, 22, 24,
                                                    14, 16, 18, 20, 22, 24,
                                                    14, 16, 18, 20, 22, 24,
                                                            18, 20, 22,
                                                     6,  6, 10, 10, 14, 14 };

   static const int dataRegionCols[] = { 8, 10, 12, 14, 16, 18, 20, 22, 24,
                                                    14, 16, 18, 20, 22, 24,
                                                    14, 16, 18, 20, 22, 24,
                                                            18, 20, 22,
                                                    16, 14, 24, 16, 16, 22 };

   static const int horizDataRegions[] = { 1, 1, 1, 1, 1, 1, 1, 1, 1,
                                                    2, 2, 2, 2, 2, 2,
                                                    4, 4, 4, 4, 4, 4,
                                                          6, 6, 6,
                                                    1, 2, 1, 2, 2, 2 };

   static const int interleavedBlocks[] = { 1, 1, 1, 1, 1, 1, 1,  1, 1,
                                                     1, 1, 1, 1,  1, 2,
                                                     2, 4, 4, 4,  4, 6,
                                                           6, 8, 10,
                                                     1, 1, 1, 1,  1, 1 };

   static const int symbolDataWords[] = { 3, 5, 8,  12,   18,   22,   30,   36,  44,
                                                    62,   86,  114,  144,  174, 204,
                                                   280,  368,  456,  576,  696, 816,
                                                              1050, 1304, 1558,
                                                     5,   10,   16,   22,   32,  49 };

   static const int blockErrorWords[] = { 5, 7, 10, 12, 14, 18, 20, 24, 28,
                                                    36, 42, 48, 56, 68, 42,
                                                    56, 36, 48, 56, 68, 56,
                                                            68, 62, 62,
                                                     7, 11, 14, 18, 24, 28 };

   static const int blockMaxCorrectable[] = { 2, 3, 5,  6,  7,  9,  10,  12,  14,
                                                       18, 21, 24,  28,  34,  21,
                                                       28, 18, 24,  28,  34,  28,
                                                               34,  31,  31,
                                                   3,  5,  7,   9,  12,  14 };

   if(sizeIdx < 0 || sizeIdx >= DmtxSymbolSquareCount + DmtxSymbolRectCount)
      return DmtxUndefined;

   switch(attribute) {
      case DmtxSymAttribSymbolRows:
         return symbolRows[sizeIdx];
      case DmtxSymAttribSymbolCols:
         return symbolCols[sizeIdx];
      case DmtxSymAttribDataRegionRows:
         return dataRegionRows[sizeIdx];
      case DmtxSymAttribDataRegionCols:
         return dataRegionCols[sizeIdx];
      case DmtxSymAttribHorizDataRegions:
         return horizDataRegions[sizeIdx];
      case DmtxSymAttribVertDataRegions:
         return (sizeIdx < DmtxSymbolSquareCount) ? horizDataRegions[sizeIdx] : 1;
      case DmtxSymAttribMappingMatrixRows:
         return dataRegionRows[sizeIdx] *
               dmtxGetSymbolAttribute(DmtxSymAttribVertDataRegions, sizeIdx);
      case DmtxSymAttribMappingMatrixCols:
         return dataRegionCols[sizeIdx] * horizDataRegions[sizeIdx];
      case DmtxSymAttribInterleavedBlocks:
         return interleavedBlocks[sizeIdx];
      case DmtxSymAttribBlockErrorWords:
         return blockErrorWords[sizeIdx];
      case DmtxSymAttribBlockMaxCorrectable:
         return blockMaxCorrectable[sizeIdx];
      case DmtxSymAttribSymbolDataWords:
         return symbolDataWords[sizeIdx];
      case DmtxSymAttribSymbolErrorWords:
         return blockErrorWords[sizeIdx] * interleavedBlocks[sizeIdx];
      case DmtxSymAttribSymbolMaxCorrectable:
         return blockMaxCorrectable[sizeIdx] * interleavedBlocks[sizeIdx];
   }

   return DmtxUndefined;
}

/**
 * \brief  Retrieve data size for a specific symbol size and block number
 * \param  sizeIdx
 * \param  blockIdx
 * \return Attribute value
 */
extern int
dmtxGetBlockDataSize(int sizeIdx, int blockIdx)
{
   int symbolDataWords;
   int interleavedBlocks;
   int count;

   symbolDataWords = dmtxGetSymbolAttribute(DmtxSymAttribSymbolDataWords, sizeIdx);
   interleavedBlocks = dmtxGetSymbolAttribute(DmtxSymAttribInterleavedBlocks, sizeIdx);

   if(symbolDataWords < 1 || interleavedBlocks < 1)
      return DmtxUndefined;

   count = (int)(symbolDataWords/interleavedBlocks);

   return (sizeIdx == DmtxSymbol144x144 && blockIdx < 8) ? count + 1 : count;
}

/**
 * \brief  Determine symbol size based on data size and requested properties
 * \param  dataWords
 * \param  sizeIdxRequest
 * \return Symbol size index (or DmtxUndefined if none)
 */
static int
FindSymbolSize(int dataWords, int sizeIdxRequest)
{
   int sizeIdx;
   int idxBeg, idxEnd;

   if(dataWords <= 0)
      return DmtxUndefined;

   if(sizeIdxRequest == DmtxSymbolSquareAuto || sizeIdxRequest == DmtxSymbolRectAuto) {

      if(sizeIdxRequest == DmtxSymbolSquareAuto) {
         idxBeg = 0;
         idxEnd = DmtxSymbolSquareCount;
      }
      else {
         idxBeg = DmtxSymbolSquareCount;
         idxEnd = DmtxSymbolSquareCount + DmtxSymbolRectCount;
      }

      for(sizeIdx = idxBeg; sizeIdx < idxEnd; sizeIdx++) {
         if(dmtxGetSymbolAttribute(DmtxSymAttribSymbolDataWords, sizeIdx) >= dataWords)
            break;
      }

      if(sizeIdx == idxEnd)
         return DmtxUndefined;
   }
   else {
      sizeIdx = sizeIdxRequest;
   }

   if(dataWords > dmtxGetSymbolAttribute(DmtxSymAttribSymbolDataWords, sizeIdx))
      return DmtxUndefined;

   return sizeIdx;
}