From d46ef0682e0696100b1049cb8f283508262b7019 Mon Sep 17 00:00:00 2001
From: go38coz <go38coz@mytum.de>
Date: Sat, 13 Jun 2026 21:27:54 +0200
Subject: [PATCH] Added save_bmp function to main.c to save the image array
 generated as a .bmp file

---
 Implementierung/main.c | 78 +++++++++++++++++++++++++++++++++++++++++-
 1 file changed, 77 insertions(+), 1 deletion(-)

diff --git a/Implementierung/main.c b/Implementierung/main.c
index be837a4..a2888d4 100644
--- a/Implementierung/main.c
+++ b/Implementierung/main.c
@@ -1,5 +1,81 @@
+#include <stdio.h>
+#include <stdlib.h>
+#include <stdint.h>
+
+void save_bmp(const char *filename, unsigned char *img, size_t width, ssize_t height);
+
 int main(int argc, char const *argv[])
 {
-    
     return 0;
 }
+
+
+void save_bmp(const char *filename, unsigned char *img, size_t width, ssize_t height) {
+    FILE *fptr = fopen(filename,"wb");
+    if(fptr == NULL) {
+        fprintf(stderr,"ERROR: Could not open output file at %s\n.",filename);
+        exit(EXIT_FAILURE);
+    }
+    int actual_height = (height < 0) ? -height : height;
+    size_t row_padding = (4 - (width) * 3 % 4) % 4;
+    size_t row_width = width * 3 + row_padding;
+
+    size_t image_size = actual_height * row_width;
+    size_t file_size = image_size + 54;
+
+    unsigned char file_header[14] = {
+        'B', 'M',           
+        0, 0, 0, 0,         
+        0, 0, 0, 0,         
+        54, 0, 0, 0         
+    };
+
+    file_header[2] = (unsigned char)(file_size);
+    file_header[3] = (unsigned char)(file_size >> 8);
+    file_header[4] = (unsigned char)(file_size >> 16);
+    file_header[5] = (unsigned char)(file_size >> 24);
+
+    unsigned char info_header[40] = {
+        40, 0, 0, 0,        
+        0, 0, 0, 0,         
+        0, 0, 0, 0,         
+        1, 0,               
+        24, 0,              
+        0, 0, 0, 0,         
+        0, 0, 0, 0,         
+        0x13, 0x0B, 0, 0,   
+        0x13, 0x0B, 0, 0,   
+        0, 0, 0, 0,         
+        0, 0, 0, 0          
+    };
+
+    info_header[4] = (unsigned char)(width);
+    info_header[5] = (unsigned char)(width >> 8);
+    info_header[6] = (unsigned char)(width >> 16);
+    info_header[7] = (unsigned char)(width >> 24);
+
+    uint32_t h = (uint32_t)height; 
+    info_header[8] = (unsigned char)(h);
+    info_header[9] = (unsigned char)(h >> 8);
+    info_header[10] = (unsigned char)(h >> 16);
+    info_header[11] = (unsigned char)(h >> 24);
+
+    info_header[20] = (unsigned char)(image_size);
+    info_header[21] = (unsigned char)(image_size >> 8);
+    info_header[22] = (unsigned char)(image_size >> 16);
+    info_header[23] = (unsigned char)(image_size >> 24);
+
+    fwrite(file_header,1,14,fptr);
+    fwrite(info_header,1,40,fptr);
+
+    unsigned char padding_bytes[3] = {0, 0, 0};
+
+    for(int i = 0; i < actual_height; i++) {
+        fwrite(img + (i * width * 3), 3, width, fptr);
+        if(row_padding > 0) {
+            fwrite(padding_bytes,1,row_padding,fptr);
+        }
+    }
+    
+    fclose(fptr);
+}
\ No newline at end of file