1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
|
#ifndef PNG_H
#define PNG_H
#include <stdint.h>
#include <stdio.h>
#include <stdbool.h>
#include <string.h>
#include <stdlib.h>
#include "tinyff/result.h"
#include "tinyff/common.h"
static const unsigned char PNG_SIGNATURE[8] = {
0x89, 'P', 'N', 'G', 0x0D, 0x0A, 0x1A, 0x0A
};
typedef struct {
FILE *raw;
uint32_t width;
uint32_t height;
uint8_t bit_depth;
uint8_t color_type;
uint8_t *pixels;
size_t count_pixels;
bool valid;
} ff_png_ctx;
typedef struct {
uint32_t length;
const char *type;
uint32_t *data; // length bytes (maximum is uint32_t)
uint32_t crc;
} ff_png_chunk;
// Chunk handling
typedef (*ff_png_chunk_handler_ptr)(uint8_t *buf, size_t len, ff_png_ctx* ctx);
typedef struct {
const char *type;
ff_png_chunk_handler_ptr handler;
} ff_png_chunk_handler;
const ff_png_chunk_handler ff_png_chunk_handlers[] = {
{"IHDR", ff_png_header_handler},
{"IDAT", ff_png_data_handler},
{"IEND", ff_png_end_handler},
{NULL, NULL} // Terminator
};
// Handler declarations
// Massive W.I.P
// Required by definition
void ff_png_header_handler(uint8_t *buf, size_t len, ff_png_ctx* ctx); // IHDR
void ff_png_data_handler(uint8_t *buf, size_t len, ff_png_ctx* ctx); // IDAT
void ff_png_end_handler(uint8_t *buf, size_t len, ff_png_ctx* ctx); // IEND
// PLTE is a funny one
// Its only required for indexed color types
ff_result ff_png_isvalid(FILE *file);
ff_result ff_open_png(const char *filepath, ff_png_ctx **out_ctx);
#endif
|
