importing old mnist loader

Author: kemsig

include/TensorSANN/data/MNISTDataset.hpp

@@ -10,11 +10,13 @@ namespace TensorSANN{
 class MNISTDataset : public Dataset<float>{
     protected:
         std::vector<Tensor> images;
-        std::vector<int> labels;
+        std::vector<unsigned int> labels;
 
     public:
+        MNISTDataset(std::string labels_path, std::string images_path);
         size_t size() const override;
         std::pair<Tensor, int> get_item(size_t index) const override;
+        void print_mnist_index(int index);
 
 
 };

src/data/MNISTDataset.cpp

@@ -1,66 +1,119 @@
 #include "TensorSANN/data/MNISTDataset.hpp"
 #include "TensorSANN/utils/Tensor.hpp"
-#include <fstream>
+
 #include <stdexcept>
+#include <iostream>
+#include <fstream>
+#include <vector>
 
 #define MNIST_IMAGE_MNUM 2051
 #define MNIST_LABEL_MNUM 2049
 #define MINIST_IMG_DIM 28
 
 
+namespace TensorSANN{
+    
+static std::vector<unsigned int> load_mnist_labels(std::string path){
+    std::ifstream file(path, std::ios::binary);
+    if (!file.is_open()) {
+        throw std::invalid_argument("Could not open file.");
+    }
 
-protected:
-std::vector<Tensor> images;
-std::vector<int> labels;
+    int magic_number = 0;
+    file.read(reinterpret_cast<char*>(&magic_number), 4);
+    magic_number = __builtin_bswap32(magic_number);
 
+    if (magic_number != MNIST_LABEL_MNUM) throw std::invalid_argument("Invalid magic nubmer.");
 
-static std::vector<unsigned int> load_mnist_labels(std::string path){
+    int num_labels = 0;
+    file.read(reinterpret_cast<char*>(&num_labels), 4);
+    num_labels = __builtin_bswap32(num_labels);
 
-    std::ifstream file(path, std::ios::binary);
-    if (!file.is_open()) {
-        throw std::invalid_argument("Could not open file: %s", path);
+    std::vector<unsigned int> labels;
+    for (int i = 0; i < num_labels; i++) {
+        uint8_t label;
+        file.read(reinterpret_cast<char*>(&label), 1);
+        labels.push_back(label);
     }
 
+    file.close();
+
+    return labels;
+
 
 }
-static std::vector<Tensor> MNISTDataset::load_mnist_images(std::string path){
+static std::vector<Tensor> load_mnist_images(std::string path){
     std::ifstream file(path, std::ios::binary);
     if (!file.is_open()) {
-        throw std::invalid_argument("Could not open file: %s", path);
+        throw std::invalid_argument("Could not open file.");
     }
 
     int magic_number = 0;
     file.read(reinterpret_cast<char*>(&magic_number), 4);
     magic_number = __builtin_bswap32(magic_number); // Convert from big-endian
 
-    if (magic_number != MNIST_IMAGE_MNUM) throw std::invalid_argume
+    if (magic_number != MNIST_IMAGE_MNUM) throw std::invalid_argument("Invalid magic number.");
 
+    int num_images = 0;
     file.read(reinterpret_cast<char*>(&num_images), 4);
     num_images = __builtin_bswap32(num_images);
 
+    size_t rows = 0;
     file.read(reinterpret_cast<char*>(&rows), 4);
     rows = __builtin_bswap32(rows);
 
+    size_t cols = 0;
     file.read(reinterpret_cast<char*>(&cols), 4);
     cols = __builtin_bswap32(cols);
 
-    vector<vector<uint8_t>> images(num_images, vector<uint8_t>(rows * cols));
+    std::vector<Tensor> images;
     for (int i = 0; i < num_images; i++) {
-        file.read(reinterpret_cast<char*>(images[i].data()), rows * cols);
+        std::vector<float> buffer(rows * cols);
+        file.read(reinterpret_cast<char*>(buffer.data()), rows * cols);
+        
+        //@@ temporary
+        images.push_back(Tensor({rows * cols, 1}, buffer) / 255.0);
     }
-
     file.close();
     return images;
 }
 
+MNISTDataset::MNISTDataset(std::string labels_path, std::string images_path){
+    labels = load_mnist_labels(labels_path);
+    images = load_mnist_images(images_path);
+
+}
 
-size_t MNISTDataset::size(){
 
+size_t MNISTDataset::size(){
+    return 0;
 }
 std::pair<Tensor, int> MNISTDataset::get_item(size_t index){
 
 }
 
+static char pixel_to_char(float pixel_value) {
+    if (pixel_value > 0.8f) return '#'; // Dark pixel
+    else if (pixel_value > 0.6f) return 'O'; // Medium-dark pixel
+    else if (pixel_value > 0.4f) return '+'; // Medium pixel
+    else if (pixel_value > 0.2f) return '.';  // Light pixel
+    else return ' ';  // Very light pixel (almost white)
+}
+
+void TensorSANN::print_mnist_index(int index){
+    auto image = images[index].data;
+    int label = labels[index];
+    std::cout << "Index: " << index << " Label: " << label << std::endl;
+
+    for (int i = 0; i < MINIST_IMG_DIM; i++) {
+        for (int j = 0; j < MINIST_IMG_DIM; j++) {
+            printf("%c ", pixel_to_char(image[i * MINIST_IMG_DIM + j]));
+        }
+        printf("\n");
+    }
+
+}
+}