1 files changed, 66 insertions, 0 deletions
diff --git a/python/openvino/runtime/common/format_reader/MnistUbyte.cpp b/python/openvino/runtime/common/format_reader/MnistUbyte.cpp
new file mode 100644
index 0000000..182ef99
--- /dev/null
+++ b/python/openvino/runtime/common/format_reader/MnistUbyte.cpp
@@ -0,0 +1,66 @@
+// Copyright (C) 2018-2022 Intel Corporation
+// SPDX-License-Identifier: Apache-2.0
+//
+
+// clang-format off
+#include <fstream>
+#include <iostream>
+#include <string>
+
+#include "MnistUbyte.h"
+// clang-format on
+
+using namespace FormatReader;
+
+int MnistUbyte::reverseInt(int i) {
+    unsigned char ch1, ch2, ch3, ch4;
+    ch1 = (unsigned char)(i & 255);
+    ch2 = (unsigned char)((i >> 8) & 255);
+    ch3 = (unsigned char)((i >> 16) & 255);
+    ch4 = (unsigned char)((i >> 24) & 255);
+    return (static_cast<int>(ch1) << 24) + (static_cast<int>(ch2) << 16) + (static_cast<int>(ch3) << 8) + ch4;
+}
+
+MnistUbyte::MnistUbyte(const std::string& filename) {
+    std::ifstream file(filename, std::ios::binary);
+    if (!file.is_open()) {
+        return;
+    }
+    int magic_number = 0;
+    int number_of_images = 0;
+    int n_rows = 0;
+    int n_cols = 0;
+    file.read(reinterpret_cast<char*>(&magic_number), sizeof(magic_number));
+    magic_number = reverseInt(magic_number);
+    if (magic_number != 2051) {
+        return;
+    }
+    file.read(reinterpret_cast<char*>(&number_of_images), sizeof(number_of_images));
+    number_of_images = reverseInt(number_of_images);
+    file.read(reinterpret_cast<char*>(&n_rows), sizeof(n_rows));
+    n_rows = reverseInt(n_rows);
+    _height = (size_t)n_rows;
+    file.read(reinterpret_cast<char*>(&n_cols), sizeof(n_cols));
+    n_cols = reverseInt(n_cols);
+    _width = (size_t)n_cols;
+    if (number_of_images > 1) {
+        std::cout << "[MNIST] Warning: number_of_images  in mnist file equals " << number_of_images
+                  << ". Only a first image will be read." << std::endl;
+    }
+
+    size_t size = _width * _height * 1;
+
+    _data.reset(new unsigned char[size], std::default_delete<unsigned char[]>());
+    size_t count = 0;
+    if (0 < number_of_images) {
+        for (int r = 0; r < n_rows; ++r) {
+            for (int c = 0; c < n_cols; ++c) {
+                unsigned char temp = 0;
+                file.read(reinterpret_cast<char*>(&temp), sizeof(temp));
+                _data.get()[count++] = temp;
+            }
+        }
+    }
+
+    file.close();
+}