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[FILE BEGIN]
1/**
2 * BITMAP
3 * © 2025 0x4248
4 */
5
6#include <stdio.h>
7#include <stdlib.h>
8#include <stdint.h>
9#include "bmp_head.h"
10#include "bmp_pixel.h"
11
12void printRGB(PIXEL24 *pixels, int width, int height, int row_padded) {
13    for (int x = 0; x < width; x++) {
14        PIXEL24 *row = (PIXEL24 *)((uint8_t *)pixels + (height - 1 - x) * row_padded);
15            for (int y = 0; y < height; y++) {
16            printf("%d,%d:%u,%u,%u\n",
17                   x, y, row[x].r, row[x].g, row[x].b);
18        }
19    }
20}
21
22int main(int argc, char *argv[]) {
23    if (argc != 2) {
24        printf("Usage: %s <bitmap_file.bmp>\n", argv[0]);
25        return 1;
26    }
27
28    const char *filename = argv[1];
29    FILE *fp = fopen(filename, "rb");
30    if (!fp) {
31        perror("Error opening file");
32        return 1;
33    }
34
35    BM_FILE_HEAD fileHeader;
36
37
38    fread(&fileHeader, sizeof(BM_FILE_HEAD), 1, fp);
39    BM_INFO_V3 infoHeaderV3 = {0};
40    BM_INFO_V2 infoHeaderV2 = {0};
41    BM_INFO_V1 infoHeader = {0};
42
43    printf("Reading base header\n");
44    fread(&infoHeader, sizeof(BM_INFO_V1), 1, fp);
45
46    switch (fileHeader.biSize) {
47        case 52:
48            printf("Using V2\n");
49            fread(&infoHeaderV2, sizeof(BM_INFO_V2), 1, fp);
50            break;
51
52        case 56:
53            printf("Using V2\n");
54            fread(&infoHeaderV2, sizeof(BM_INFO_V2), 1, fp);
55            printf("Using V3\n");
56            fread(&infoHeaderV3, sizeof(BM_INFO_V3), 1, fp);
57            break;
58
59        default:
60            printf("Only using V1");
61            fclose(fp);
62            return 1;
63    }
64
65    if (fileHeader.bfType != 0x4D42) { // 'BM' in little endian
66        printf("Error: Not a valid BMP file.\n");
67        fclose(fp);
68        return 1;
69    }
70
71    printf("\n=== FILE HEADER ===\n");
72    printf("File Size: %u bytes\n", fileHeader.bfSize);
73    printf("Data Offset: %u bytes\n", fileHeader.bfOffBits);
74    printf("Header Size: %u bytes\n", fileHeader.biSize);
75
76    printf("\n=== BITMAP INFO ===\n");
77    printf("Width: %d px\n", infoHeader.biWidth);
78    printf("Height: %d px\n", infoHeader.biHeight);
79    printf("Bits per Pixel: %u\n", infoHeader.biBitCount);
80
81    int row_bytes = (infoHeader.biWidth * 3 + 3) & ~3;
82    int width = infoHeader.biWidth;
83    int height = infoHeader.biHeight;
84    int row_padded = (width * sizeof(PIXEL24) + 3) & ~3;
85
86    PIXEL24 *pixels = malloc(row_padded * height);
87
88    fseek(fp, fileHeader.bfOffBits, SEEK_SET);
89
90    for (int y = 0; y < height; y++) {
91        fread((uint8_t*)pixels + y * row_padded, 1, row_padded, fp);
92    }
93
94    printRGB(pixels, width, height, row_padded);
95
96    fclose(fp);
97    return 0;
98}
99
[FILE END]
(C) 2025 0x4248
(C) 2025 4248 Media and 4248 Systems, All part of 0x4248
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