#define ID_LENGTH 34
#define MODE_INDICATOR_LENGTH 4
+std::vector<unsigned int> log_table(256, 0), antilog_table(255,0);
+
std::string id_generator(unsigned int seed);
+std::size_t get_degree(std::vector<unsigned int> polynomial);
+std::vector<unsigned int> field_multiply(std::vector<unsigned int> polynomial, unsigned int value);
int main() {
//std::cout << id_generator(69) << std::endl;
}
std::cout << std::endl;
*/
-
// Convert character count indicator to binary (10 bits for version 1-H):
std::bitset<10> character_count_indicator {input_length};
for (std::size_t i{0}; i < character_count_indicator.size(); ++i){
}
std::cout << std::endl;
*/
-
// Numeric data type
std::vector<bool> mode_indicator{0,0,0,1};
input_data_vector.insert(input_data_vector.begin(), mode_indicator.begin(), mode_indicator.end());
// terminator
std::vector<bool> terminator{0,0,0,0};
input_data_vector.insert(input_data_vector.end(), terminator.begin(), terminator.end());
-
+ /*
int k = 0;
for (auto i : input_data_vector){
k++;
}
std::cout << std::endl;
-
+ */
// padding bits
for (std::size_t i{0}; i < input_data_vector.size() % 8; ++i){
input_data_vector.push_back(0);
}
-
- k = 0;
+ int k = 0;
for (auto i : input_data_vector){
if (k != 0 && k % 8 == 0){std::cout << " ";}
std::cout << i;
std::cout << "Length: " << input_data_vector.size() << std::endl;
std::cout << "Number of data codewords: " << input_data_vector.size() / 8 << std::endl;
-
// padding bits for codewords for V1 QR code with M-level error correction (table 8)
std::vector<bool> pad_codeword1 = {1,1,1,0,1,1,0,0};
std::vector<bool> pad_codeword2 = {0,0,0,1,0,0,0,1};
unsigned int primitive = 0b100011101;
std::cout << "Primitive: " << primitive << std::endl;
//unsigned int log_table[255]{}, antilog_table[510]{};
- std::vector<unsigned int> log_table, antilog_table(510,0);
-
- //std::cout << "Log table: ";
for (unsigned int i{0}; i < 255; ++i){
if (i == 0){
- log_table.push_back(1);
- }
- else if (log_table[i-1] * 2 > 255){
- log_table.push_back((log_table[i-1] * 2) ^ primitive);
+ antilog_table[0] = 1;
}
else {
- log_table.push_back((log_table[i-1] * 2));
+ unsigned int antilog_value = antilog_table[i-1] * 2;
+ if (antilog_value >= 255){
+ antilog_value ^= primitive;
+ }
+ antilog_table[i] = antilog_value;
}
- //std::cout << log_table[i] << " ";
}
- //std::cout << std::endl;
+ //std::cout << "Antilog table: ";for (unsigned int i{0}; i <255;++i){std::cout << antilog_table[i] << " ";}std::cout << std::endl;
+
- //std::cout << "Antilog table: ";
- for (unsigned int i{0}; i < 255; ++i){
- antilog_table[log_table[i]] = i;
- antilog_table[510-log_table[i]-1] = i;
- }
- for (unsigned int i{0}; i < 510;++i){
- //std::cout << antilog_table[i] << " ";
+ for (unsigned int i{0}; i < 256; ++i){
+ if (i == 0){
+ log_table[0] = -1;
+ }
+ else {
+ log_table[antilog_table[i]] = i;
+ }
+
}
- //std::cout << std::endl;
+
+ //std::cout << "Log table: ";for (auto i: log_table){std::cout << i << " ";}std::cout << std::endl;
+
+ // print out important values in log table
+ /*
+ std::cout << log_table[1] << std::endl;
+ std::cout << log_table[2] << std::endl;
+ std::cout << log_table[4] << std::endl;
+ std::cout << log_table[8] << std::endl;
+ std::cout << log_table[16] << std::endl;
+ std::cout << log_table[32] << std::endl;
+ std::cout << log_table[64] << std::endl;
+ std::cout << log_table[128] << std::endl;
+ std::cout << log_table[29] << std::endl;
+ std::cout << log_table[58] << std::endl;
+ */
// Data polynomial
std::vector<unsigned int> data_polynomial(16,0);
for (unsigned int i{0}; i < 10; ++i){
data_polynomial.push_back(0);
}
+
+ std::cout << "Data Polynomial (size: "<< data_polynomial.size() << "): ";
for (auto i : data_polynomial){
std::cout << i << " ";
}
// Generator Polynomial
std::vector<unsigned int> generator_polynomial = {1, antilog_table[251], antilog_table[67], antilog_table[46], antilog_table[61], antilog_table[118], antilog_table[70], antilog_table[64], antilog_table[94], antilog_table[32], antilog_table[45]};
+
+ std::size_t generator_shift_amount = data_polynomial.size() - generator_polynomial.size();
+ for (std::size_t i{0}; i < generator_shift_amount; ++i){
+ generator_polynomial.push_back(0);
+ }
+
+ std::cout << "Generator Polynomial (size: " << generator_polynomial.size() << "): ";
for (auto i : generator_polynomial){
std::cout << i << " ";
}
std::cout << std::endl;
// remainder polynomial
- std::vector<unsigned int> remainder;
+ std::vector<unsigned int> remainder = data_polynomial;
+ for (unsigned int c{0}; c <= generator_shift_amount; ++c){
+ // find scaling factor for generator polynomial
+ unsigned int scaling_factor = antilog_table[log_table[remainder[remainder.size() - 1 - get_degree(remainder)]] - log_table[generator_polynomial[generator_polynomial.size() - 1 - get_degree(generator_polynomial)]]];
+ if (scaling_factor < 0){
+ scaling_factor += 255;
+ }
+ generator_polynomial = field_multiply(generator_polynomial, scaling_factor);
+ //std::cout << scaling_factor << std::endl;
+ //std::cout << "after field multiply: "; for (auto val: generator_polynomial){std::cout << val << " ";}std::cout<<std::endl;
+ for (std::size_t i{0}; i < remainder.size(); ++i){
+ remainder[i] ^= generator_polynomial[i];
+ if (remainder[i] > 255){
+ remainder[i] ^= primitive;
+ }
+ //std::cout << remainder[i] << " ";
+ }
+ //std::cout << std::endl;
+ unsigned int unscaling_factor = ((255 - log_table[scaling_factor]) % 255 + 255) % 255;
+ generator_polynomial = field_multiply(generator_polynomial, antilog_table[unscaling_factor]);
+ //std::cout << "after unmultiply: "; for (auto val: generator_polynomial){std::cout << val << " ";}std::cout<<std::endl;
+
+ generator_polynomial.insert(generator_polynomial.begin(), 0);
+ generator_polynomial.pop_back();
+ }
+
+ //std::cout << get_degree(remainder) << std::endl;
+ //std::cout << "Error correction codewords: ";for (auto i: remainder){std::cout << i << " ";}std::cout << std::endl;
+
+ remainder.erase(remainder.begin(), remainder.begin() + remainder.size() - get_degree(remainder) - 1);
+ std::cout << "Error correction codewords: ";for (auto i: remainder){std::cout << i << " ";}std::cout << std::endl;
+
+
+
+
+
return 0;
}
+// do not use until main function has defined log and antilog tables;
+std::vector<unsigned int> field_multiply(std::vector<unsigned int> polynomial, unsigned int value){
+ if (value == 0){
+ return std::vector<unsigned int>(polynomial.size(), 0);
+ }
+ for (std::size_t i{0}; i < polynomial.size(); ++i){
+ if (polynomial[i] == 0) {
+ polynomial[i] = 0;
+ }
+ else{
+ unsigned int log_sum = (log_table[value] + log_table[polynomial[i]]) % 255;
+ polynomial[i] = antilog_table[log_sum];
+ }
+ }
+ return polynomial;
+}
+
+
+std::size_t get_degree(std::vector<unsigned int> polynomial){
+ for (std::size_t i{0}; i < polynomial.size(); ++i){
+ if (polynomial[i] != 0){
+ return polynomial.size() - i - 1;
+ }
+ }
+ return polynomial.size() - 1;
+}
+
+
std::string id_generator(unsigned int seed){
srand(seed);
std::string ID{};
projects / qrcodescanner.git / commitdiff