code: private static boolean cv_from_64(long[] res, char[] str )
  	{
  	    int len, i, j, index;
  
  	    for(len = 1; len<5; len++)
  	    	if(str[len]=='\0') break;
  
  	    res[0]=0;
  
  	    for (i = 0; i < len; i++) {
  	        index = -1;
  	        for (j = 0; j < 64; j++) {
  	            if (cConversionTable[j] == str[i]) {
  	               index = j;
  	               break;
  	            }
  	        }
  	        if (index == -1)
  	            return false;
  	        res[0] = res[0] * 64 + index;
  	    }
  	    return true;
  	}
docs: Calculate a numberer from the code
  @param res
  @param str
  @return true if no error occurred