Обновить sk1/compressor.c

sk1/compressor.c

@@ -1,4 +1,275 @@
-int compress_1(const char* input_file_name, const char* output_file_name);
+#include <stdio.h>
-int decompress_1(const char* input_file_name, const char* output_file_name);
+#include <stdlib.h>
+#include <string.h>
+
+#define MAX_TREE_HT 256
+
+// A Huffman tree node
+struct MinHeapNode {
+    unsigned char data;
+    unsigned freq;
+    struct MinHeapNode *left, *right;
+};
+
+// A MinHeap
+struct MinHeap {
+    unsigned size;
+    unsigned capacity;
+    struct MinHeapNode** array;
+};
+
+// Function to create a new node
+struct MinHeapNode* createNode(unsigned char data, unsigned freq) {
+    struct MinHeapNode* temp = (struct MinHeapNode*)malloc(sizeof(struct MinHeapNode));
+    temp->data = data;
+    temp->freq = freq;
+    temp->left = temp->right = NULL;
+    return temp;
+}
+
+// Function to create a MinHeap
+struct MinHeap* createMinHeap(unsigned capacity) {
+    struct MinHeap* minHeap = (struct MinHeap*)malloc(sizeof(struct MinHeap));
+    minHeap->size = 0;
+    minHeap->capacity = capacity;
+    minHeap->array = (struct MinHeapNode**)malloc(minHeap->capacity * sizeof(struct MinHeapNode*));
+    return minHeap;
+}
+
+// Swap function
+void swapMinHeapNode(struct MinHeapNode** a, struct MinHeapNode** b) {
+    struct MinHeapNode* t = *a;
+    *a = *b;
+    *b = t;
+}
+
+// MinHeapify function
+void minHeapify(struct MinHeap* minHeap, int idx) {
+    int smallest = idx;
+    int left = 2 * idx + 1;
+    int right = 2 * idx + 2;
+
+    if (left < minHeap->size && minHeap->array[left]->freq < minHeap->array[smallest]->freq)
+        smallest = left;
+
+    if (right < minHeap->size && minHeap->array[right]->freq < minHeap->array[smallest]->freq)
+        smallest = right;
+
+    if (smallest != idx) {
+        swapMinHeapNode(&minHeap->array[smallest], &minHeap->array[idx]);
+        minHeapify(minHeap, smallest);
+    }
+}
+
+// Extract minimum value node from heap
+struct MinHeapNode* extractMin(struct MinHeap* minHeap) {
+    struct MinHeapNode* temp = minHeap->array[0];
+    minHeap->array[0] = minHeap->array[minHeap->size - 1];
+    --minHeap->size;
+    minHeapify(minHeap, 0);
+    return temp;
+}
+
+// Insert a new node to MinHeap
+void insertMinHeap(struct MinHeap* minHeap, struct MinHeapNode* minHeapNode) {
+    ++minHeap->size;
+    int i = minHeap->size - 1;
+    while (i && minHeapNode->freq < minHeap->array[(i - 1) / 2]->freq) {
+        minHeap->array[i] = minHeap->array[(i - 1) / 2];
+        i = (i - 1) / 2;
+    }
+    minHeap->array[i] = minHeapNode;
+}
+
+// Build the MinHeap
+void buildMinHeap(struct MinHeap* minHeap) {
+    int n = minHeap->size - 1;
+    for (int i = (n - 1) / 2; i >= 0; --i)
+        minHeapify(minHeap, i);
+}
+
+// Check if size is 1
+int isSizeOne(struct MinHeap* minHeap) {
+    return (minHeap->size == 1);
+}
+
+// Create and build a MinHeap
+struct MinHeap* createAndBuildMinHeap(unsigned char data[], int freq[], int size) {
+    struct MinHeap* minHeap = createMinHeap(size);
+    for (int i = 0; i < size; ++i)
+        minHeap->array[i] = createNode(data[i], freq[i]);
+    minHeap->size = size;
+    buildMinHeap(minHeap);
+    return minHeap;
+}
+
+// Build Huffman Tree
+struct MinHeapNode* buildHuffmanTree(unsigned char data[], int freq[], int size) {
+    struct MinHeapNode *left, *right, *top;
+    struct MinHeap* minHeap = createAndBuildMinHeap(data, freq, size);
+
+    while (!isSizeOne(minHeap)) {
+        left = extractMin(minHeap);
+        right = extractMin(minHeap);
+
+        top = createNode('$', left->freq + right->freq);
+        top->left = left;
+        top->right = right;
+
+        insertMinHeap(minHeap, top);
+    }
+    return extractMin(minHeap);
+}
+
+// Print Huffman Codes to a map
+void storeCodes(struct MinHeapNode* root, char** codes, char* currentCode, int top) {
+    if (root->left) {
+        currentCode[top] = '0';
+        storeCodes(root->left, codes, currentCode, top + 1);
+    }
+    if (root->right) {
+        currentCode[top] = '1';
+        storeCodes(root->right, codes, currentCode, top + 1);
+    }
+    if (!(root->left) && !(root->right)) {
+        currentCode[top] = '\0';
+        codes[root->data] = strdup(currentCode);
+    }
+}
+// Compress the input file using Huffman Coding
+int compressFile(const char* input_file_name, const char* output_file_name) {
+    FILE* inputFile = fopen(input_file_name, "rb");
+    if (!inputFile) {
+        perror("Error opening input file");
+        return -1;
+    }
+
+    int freq[256] = {0};
+    unsigned char buffer;
+
+    // Count frequency of each byte
+    while (fread(&buffer, sizeof(unsigned char), 1, inputFile)) {
+        freq[buffer]++;
+    }
+    rewind(inputFile);
+
+    unsigned char data[256];
+    int frequencies[256], size = 0;
+    for (int i = 0; i < 256; i++) {
+        if (freq[i] > 0) {
+            data[size] = (unsigned char)i;
+            frequencies[size] = freq[i];
+            size++;
+        }
+    }
+
+    struct MinHeapNode* root = buildHuffmanTree(data, frequencies, size);
+    char* codes[256] = {0};
+    char currentCode[MAX_TREE_HT];
+    storeCodes(root, codes, currentCode, 0);
+
+    FILE* outputFile = fopen(output_file_name, "wb");
+    if (!outputFile) {
+        perror("Error opening output file");
+        fclose(inputFile);
+        return -1;
+    }
+
+    // Write codes to output file
+    fwrite(freq, sizeof(int), 256, outputFile);
+
+    unsigned char byte = 0;
+    int bitCount = 0;
+    while (fread(&buffer, sizeof(unsigned char), 1, inputFile)) {
+        char* code = codes[buffer];
+        for (int i = 0; code[i] != '\0'; i++) {
+            byte = (byte << 1) | (code[i] - '0');
+            bitCount++;
+            if (bitCount == 8) {
+                fwrite(&byte, sizeof(unsigned char), 1, outputFile);
+                byte = 0;
+                bitCount = 0;
+            }
+        }
+    }
+    if (bitCount > 0) {
+        byte <<= (8 - bitCount);
+        fwrite(&byte, sizeof(unsigned char), 1, outputFile);
+    }
+
+    fclose(inputFile);
+    fclose(outputFile);
+    return 0;
+}
+
+// Decompress the file
+int decompressFile(const char* input_file_name, const char* output_file_name) {
+    FILE* inputFile = fopen(input_file_name, "rb");
+    if (!inputFile) {
+        perror("Error opening input file");
+        return -1;
+    }
+
+    int freq[256];
+    fread(freq, sizeof(int), 256, inputFile);
+
+    unsigned char data[256];
+    int frequencies[256], size = 0;
+    for (int i = 0; i < 256; i++) {
+        if (freq[i] > 0) {
+            data[size] = (unsigned char)i;
+            frequencies[size] = freq[i];
+            size++;
+        }
+    }
+
+    struct MinHeapNode* root = buildHuffmanTree(data, frequencies, size);
+
+    FILE* outputFile = fopen(output_file_name, "wb");
+    if (!outputFile) {
+        perror("Error opening output file");
+        fclose(inputFile);
+        return -1;
+    }
+
+    struct MinHeapNode* current = root;
+    unsigned char buffer;
+    int bitCount = 0;
+    while (fread(&buffer, sizeof(unsigned char), 1, inputFile)) {
+        for (int i = 7; i >= 0; i--) {
+            int bit = (buffer >> i) & 1;
+            if (bit == 0)
+                current = current->left;
+            else
+                current = current->right;
+
+            if (!(current->left) && !(current->right)) {
+                fwrite(&current->data, sizeof(unsigned char), 1, outputFile);
+                current = root;
+            }
+        }
+    }
+
+    fclose(inputFile);
+    fclose(outputFile);
+    return 0;
+}
+
+
+
+int compress_1(const char* input_file_name, const char* output_file_name){
+	if(compressFile(input_file_name, output_file_name) == 0){
+		printf("Succsses!");
+	}
+	return 0;
+}
+
+int decompress_1(const char* input_file_name, const char* output_file_name){
+	if(decompressFile(input_file_name, output_file_name) == 0){
+                printf("Succsses!");
+        }
+        return 0;
+
+}
 int compress_2(const char* input_file_name, const char* output_file_name);
 int decompress_2(const char* input_file_name, const char* output_file_name);