maxicode.c

This is program with source code to convert ascii text files to the maxicode barcode standard.

          randloc += 1;
        }

      if ( difval > data[randloc])
        {
          
         this_error = difval - data[randloc];
	}
      else
	{
	  this_error = data[randloc] - difval;
        }

      save_val = data[randloc];
      data[randloc] = difval;    // cause error at location k
    
      save_val2 = data[1];
      data[1] = 1;
   
      printf("Data [randloc=%d,1] = %d %d \n", randloc, data[randloc], data[1]);

      syndromes( data, msg_len, ecclen/2);
  
      eras_dec_rs( data, erase_posit, 0, msg_len, ecclen/2 );
      
      if ( (data[randloc] != save_val) | ( data[1] != save_val2))
        {
	  printf(" Error at k = %d data[randloc] = %d save = %d \n", 
		 k , data[randloc], save_val );
          printf(" Error2 at k = %d data[1] = %d save = %d \n", 
		 k , data[1], save_val2 );
        }
      data[randloc] = save_val;
      data[1] = save_val2;
    }

  printf("Test two random errors at different locations \n");

  // two random errors at random locs

  for ( k = 0 ; k < 100 ; k += 1)
    {

       randint = random();
       randint2 = random();
      randint = randint & NN;
      randint2 = randint2 & NN;
      difval = randint % (NN+1);
      difval2 = randint2 % (NN+1);


      randloc = random();
      randloc = randloc % 62;

      randloc2 = random();
      randloc2 = randloc % 62;

      if (randloc == randloc2)
	{
          randloc = (randloc+ 1)% (NN+1);
        }

      if ( difval > data[randloc])
        {
          
         this_error = difval - data[randloc];
	}
      else
	{
	  this_error = data[randloc] - difval;
        }

      save_val = data[randloc];
      data[randloc] = difval;    // cause error at location k
    
      save_val2 = data[1];


      if ( difval2 > data[randloc2])
        {
          
         this_error2 = difval2 - data[randloc2];
	}
      else
	{
	  this_error2 = data[randloc2] - difval2;
        }

      save_val2 = data[randloc2];
      data[randloc2] = difval2;    // cause error at location k
    
   
      printf("Data [randloc,randloc2] = %d %d \n", data[randloc], data[randloc2]);

      syndromes( data, msg_len, ecclen/2);
  
      eras_dec_rs( data, erase_posit, 0, msg_len, ecclen/2 );
      
      if ( (data[randloc] != save_val) || ( data[randloc2] != save_val2))
        {
	  printf(" Error at k = %d data[randloc] = %d save = %d \n", 
		 k , data[randloc], save_val );
          printf(" Error2 at k = %d data[randloc2] = %d save = %d \n", 
		 k , data[randloc2], save_val2 );
        }
      data[randloc] = save_val;
      data[randloc2] = save_val2;
    }

  for(j =0; j < 20; j += 1)
    {
      printf("data[%d] =  %d \n", 42 + j, data[42+j]);

    }

  // three random errors at random locs

  printf("Testing random triple errors \n");

  for ( k = 0 ; k < 500 ; k += 1)
    {

       randint = random();
       randint2 = random();
       randint3 = random();

      randint = randint & NN;
      randint2 = randint2 & NN;
      randint3 = randint3 & NN;

      difval = randint %NN;
      difval2 = randint2 % NN;
      difval3 = randint3 % NN;

      randloc = random();
      randloc = randloc % 61;
      

      randloc2 = random();
      randloc2 = randloc % 61;

      if ( randloc2 > randloc)
        {
	  if (randloc2 - randloc != 1)
            {
              if ((randloc2 - randloc) % 2 == 0)
                {
                  randloc3 = (randloc2 - randloc)/2;
                }
              else
                {
                  randloc3 = ( 1 + randloc2 - randloc)/2;
                }
	    }
        }
      else   // randloc2 < or = randloc1
        {
          if (randloc2 != 0)
	    {
	      randloc3 = randloc2 - 1;
            }               
          else
            {
	      randloc3 = (randloc + 1) % NN;
            }
	}

      if (randloc == randloc2)
	{
          randloc = (randloc+ 1)%NN;
        }

      if ( randloc == randloc3)
        {
	  randloc = 37;
        }
      if ( difval > data[randloc])
        {
          
         this_error = difval - data[randloc];
	}
      else
	{
	  this_error = data[randloc] - difval;
        }

      save_val = data[randloc];
      data[randloc] = difval;    // cause error at location k
      //  data[randloc] = save_val ^ 1;

      if ( difval2 > data[randloc2])
        {
          
         this_error2 = difval2 - data[randloc2];
	}
      else
	{
	  this_error2 = data[randloc2] - difval2;
        }

      save_val2 = data[randloc2];
      data[randloc2] = difval2;    // cause error at location k
      //  data[randloc2] = save_val2 ^ 1;

      save_val3 = data[randloc3];
      data[randloc3] = difval3;    // cause error at location k
      //  data[randloc2] = save_val3 ^ 1;
   
      printf("Data [randloc=%d,randloc2=%d,randloc3=%d] = %d %d %d\n",
       randloc, randloc2, randloc3,
         data[randloc], data[randloc2], data[randloc3] );

      syndromes( data, msg_len, ecclen/2);
  
      eras_dec_rs( data, erase_posit, 0, msg_len, ecclen/2 );
      
      if  (data[randloc] != save_val) 
            
        {
	  printf(" Error at k = %d data[randloc] = %d save = %d \n", 
		 k , data[randloc], save_val );
        }
      if( data[randloc2] != save_val2)
        
        {
          printf(" Error2 at k = %d data[randloc2] = %d save = %d \n", 
		 k , data[randloc2], save_val2 );
        }
 
       if ( data[randloc3] != save_val3 )
        {
          printf(" Error3 at k = %d data[randloc3] = %d save = %d \n", 
		 k , data[randloc3], save_val3 );
        }
      data[randloc] = save_val;
      data[randloc2] = save_val2;
      data[randloc3] = save_val3;
    }

  for(j =0; j < 20; j += 1)
    {
      printf("data[%d] =  %d \n", 42 + j, data[42+j]);

    }

  // three random errors at random locs, error at 76

  printf("Begin random quad errors \n");

  for ( k = 0 ; k < 100 ; k += 1)
    {

       randint = random();
       randint2 = random()+ 17;
       randint3 = random()-12;
       randint4 = random()+74;

      randint = randint & NN;
      randint2 = randint2 & NN;
      randint3 = randint3 & NN;
      randint4 = randint4 & NN;

      difval = randint % NN;
      difval2 = randint2 %  NN;
      difval3 = randint3 %  NN;
      difval4 = randint4 %  NN;

      save_val = data[33];
      data[33] = difval;    // cause error at location k

      save_val2 = data[34];
      data[34] = difval2;    // cause error at location k

      save_val3 = data[35];
      data[35] = difval3;    // cause error at location k

      save_val4 = data[36];
      data[36] = difval4;    // cause error at location k

      printf("Data [33,34,35,36] = %d %d %d %d\n",
       data[33], data[34], data[35], data[36] );

      syndromes( data, msg_len, ecclen/2);
  
      printf("Done with syndromes \n");

      eras_dec_rs( data, erase_posit, 0, msg_len, ecclen/2 );
      
      printf("Returned from eras_dec_rs \n");

      if ( (data[33] != save_val) || ( data[34] != save_val2)
        || ( data[35] != save_val3 ) || ( data[36] != save_val4))
        {
          
		
	  printf(" Error at k = %d data[33] = %d save = %d \n", 
		 k , data[33], save_val );
          printf(" Error2 at k = %d data[34] = %d save = %d \n", 
		 k , data[34], save_val2 );
          printf(" Error3 at k = %d data[35] = %d save = %d \n", 
		 k , data[randloc3], save_val3 );
          printf(" Error4 at k = %d data[36] = %d save = %d \n", 
		 k , data[36], save_val4);
        }
      data[33] = save_val;
      data[34] = save_val2;
      data[35] = save_val3;
      data[36] = save_val4;
    }

  for(j =0; j < 20; j += 1)
    {
      printf("data[%d] =  %d \n", 42 + j, data[42+j]);

    }

}

void copy_ecc_bytes()
{
  int j;

  for(j = 0; j < 10; j += 1)
    {
      data[j+10] = ecc_results[j];
      
    }

}

void test_ecc_primary()
  {
int j;
 int save_val;
 int save_val2;
 int save_val3;
 int save_val4;

 int k;
 int this_error;
 int this_error2;
 int this_error3;

 int randint;
 int randint2;
 int randint3;
 int randint4;

 int randloc2;
 int randloc3;
 int randloc4;
 int randloc;

 int difval;
 int difval2;
 int difval3;
 int difval4;

 set_debug = 0;

  data[0] = 4;
  data[1] = 13;
  data[2] = 63;
  data[3] = 1;
  data[4] = 24;
  data[5] = 9;
  data[6] = 59;
  data[7] = 3;
  data[8] = 15;
  data[9] = 4;

  set_debug = 0;

  codeindex = 10;

  generateEC(  data, 10, 10 );  /* do the error correction, 10  */

  for(j = 0; j < 10; j += 1)
    {
      data[j+10] = ecc_results[j];
      
    }

  syndromes( data, 20, 5 );    // total data = 20  codes, 5  syndromes */
                               //  10 data + 10 ecc

  for (j = 0; j < 10; j += 1)
    {
      erase_posit[j] = 0;
    }

  // eras_dec_rs ( data, erasures, number_of_erasures, data length
  //                        syndrome_length);

  eras_dec_rs( data, erase_posit, 0 , 20, 5 );   

  for(j =0; j < 10; j += 1)
    {
      printf("data[%d] =  %d \n", 10 + j, data[10+j]);

    }

  codeindex = 10;

  generateEC(  data, 10, 10 );  /* do the error correction, 64  */

  copy_ecc_bytes();

  data[0] = 5;  // cause an error in the recieved data...

  syndromes( data, 20, 5);    // total data = 10 codes, 5 syndromes */

 
  for (j = 0; j < 10; j += 1)
    {
      erase_posit[j] = 0;
    }

  printf("before data[9] = %d \n", data[9]);

  
  eras_dec_rs( data, erase_posit, 0, 20,  5 );  

  printf("after data[9] = %d \n", data[9]);

   data[0] = 4;

  for ( k = 0 ; k < 10 ; k += 1)
    {
      this_error = data[k] - 5;
      save_val = data[k];
      data[k] = 5;         // cause error at location k
      
      syndromes( data, 20, 5);
  
      eras_dec_rs( data, erase_posit, 0, 20, 5 );
      
      if (data[k] != save_val)
        {
	  printf(" Error at k = %d data[k] = %d save = %d \n", 
		 k , data[k], save_val );
        }
      data[k] = save_val;
    }

  // test random single errors  at data[5]

  printf("Testing random single errors \n");

  for ( k = 0 ; k < 100 ; k += 1)
    {
      randint = random();
      randint = randint & NN;
      difval = randint;

      if ( difval > data[5])
        {
          
         this_error = difval - data[5];
	}
      else
	{
	  this_error = data[5] - difval;
        }

      save_val = data[5];
      data[5] = difval;    // cause error at location k
      
   
      syndromes( data, 20, 5);
  
      eras_dec_rs( data, erase_posit, 0, 20, 5 );
      
      if (data[5] != save_val)
        {
	  printf(" Error at k = %d data[k] = %d save = %d \n", 
		 k , data[5], save_val );
        }
      data[5] = save_val;
    }

  // simple double errors

  printf("Testing random double errors data[0] = random data[1] = 1 \n");

  data[0] = 4;   // 4
  data[1] = 13;  // 13
  data[2] = 63; 
  data[3] = 1;
  data[4] = 24;
  data[5] = 9;
  data[6] = 59;
  data[7] = 3;
  data[8] = 15;
  data[9] = 4;


  // one random error at 0 and error of 1 at 1

  set_debug = 0;
  for ( k = 0 ; k < 100 ; k += 1)
    {

       randint = random();
      randint = randint & NN;
      difval = randint;

      if ( difval > data[0])
        {
          
         this_error = difval - data[0];
	}
      else
	{
	  this_error = data[0] - difval;
        }

      save_val = data[0];
      data[0] = difval;    // cause error at location k
    
      save_val2 = data[1];
      data[1] = 1;
   
      printf("Data [0,1] = %d %d \n", data[0], data[1]);

      syndromes( data, 20, 5);
  
      eras_dec_rs( data, erase_posit, 0, 20, 5 );
      
      if ( (data[0] != save_val) | ( data[1] != save_val2))
        {
	  printf(" Error at k = %d data[0] = %d save = %d \n", 
		 k , data[0], save_val );
          printf(" Error2 at k = %d data[1] = %d save = %d \n", 
		 k , data[1], save_val2 );
        }
      data[0] = save_val;
      data[1] = save_val2;
    }

  // random error at random loc and error at 1

  printf("Testing two random errors at data[0] and data[1] \n");

  for ( k = 0 ; k < 100 ; k += 1)
    {

       randint = random();
      randint = randint & NN;
      difval = randint ;

      randloc = random();
      randloc = randloc % 10;

      if (randloc == 1)
	{
          randloc += 1;
        }

      if ( difval > data[randloc])
        {
          
         this_error = difval - data[randloc];
	}
      else
	{
	  this_error = data[randloc] - difval;
        }

      save_val = data[randloc];
      data[randloc] = difval;    // cause error at location k
    
      save_val2 = data[1];
      data[1] = 1;
   
      printf("Data [randloc,1] = %d %d \n", data[randloc], data[1]);