Update pikture.c

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Nexoniarz 2026-05-14 22:31:02 +00:00 • committed by GitHub
commit e6406519f2
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110
pikture.c
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@ -36,31 +36,22 @@ static uint8_t system_is_be() {
return *((uint8_t*)&x) == 0; return *((uint8_t*)&x) == 0;
} }
static uint16_t read_u16_be(FILE* f) {
uint8_t bytes[2];
fread(bytes, 1, 2, f);
return (bytes[0] << 8) | bytes[1];
}
static void write_u16_be(FILE* f, uint16_t value) {
uint8_t bytes[2] = { (value >> 8) & 0xFF, value & 0xFF };
fwrite(bytes, 1, 2, f);
}
pikture_t* pikture_load(const char* filename) { pikture_t* pikture_load(const char* filename) {
FILE* f = fopen(filename, "rb"); FILE* f = fopen(filename, "rb");
if (!f) return NULL; if (!f) return NULL;
char magic[4]; uint8_t header[11];
fread(magic, 1, 4, f); if (fread(header, 1, 11, f) != 11) {
if (memcmp(magic, PIKT_MAGIC, 4) != 0) {
fclose(f); fclose(f);
return NULL; return NULL;
} }
uint8_t version; if (memcmp(header, PIKT_MAGIC, 4) != 0) {
fread(&version, 1, 1, f); fclose(f);
if (version != PIKT_VERSION) { return NULL;
}
if (header[4] != PIKT_VERSION) {
fclose(f); fclose(f);
return NULL; return NULL;
} }
@ -71,16 +62,21 @@ pikture_t* pikture_load(const char* filename) {
return NULL; return NULL;
} }
img->width = read_u16_be(f); img->endianness = header[10];
img->height = read_u16_be(f);
uint8_t depth;
fread(&depth, 1, 1, f);
img->channels = 4;
fread(&img->endianness, 1, 1, f); if (img->endianness) {
img->width = (header[5] << 8) | header[6];
img->height = (header[7] << 8) | header[8];
} else {
img->width = (header[6] << 8) | header[5];
img->height = (header[8] << 8) | header[7];
}
size_t data_size = (size_t)img->width * img->height * 4; img->depth = header[9];
img->channels = (img->depth + 7) / 8;
if (img->channels == 0) img->channels = 1;
size_t data_size = (size_t)img->width * img->height * img->channels;
img->pixels = (uint8_t*)malloc(data_size); img->pixels = (uint8_t*)malloc(data_size);
if (!img->pixels) { if (!img->pixels) {
free(img); free(img);
@ -120,6 +116,7 @@ pikture_t* pikture_load(const char* filename) {
b = (uint8_t)(b + (b0 & 0x03) - 2); b = (uint8_t)(b + (b0 & 0x03) - 2);
} else if (match == 0x80) { } else if (match == 0x80) {
int b1 = fgetc(f); int b1 = fgetc(f);
if (b1 == EOF) break;
int8_t dg = (b0 & 0x3F) - 32; int8_t dg = (b0 & 0x3F) - 32;
r = (uint8_t)(r + dg + ((b1 >> 4) & 0x0F) - 8); r = (uint8_t)(r + dg + ((b1 >> 4) & 0x0F) - 8);
g = (uint8_t)(g + dg); g = (uint8_t)(g + dg);
@ -128,9 +125,9 @@ pikture_t* pikture_load(const char* filename) {
int run = (b0 & 0x3F) + 1; int run = (b0 & 0x3F) + 1;
for (int i = 0; i < run && ptr < data_size; i++) { for (int i = 0; i < run && ptr < data_size; i++) {
img->pixels[ptr++] = r; img->pixels[ptr++] = r;
img->pixels[ptr++] = g; if (img->channels >= 2) img->pixels[ptr++] = (img->channels == 2) ? a : g;
img->pixels[ptr++] = b; if (img->channels >= 3) img->pixels[ptr++] = b;
img->pixels[ptr++] = a; if (img->channels >= 4) img->pixels[ptr++] = a;
} }
continue; continue;
} }
@ -144,9 +141,9 @@ pikture_t* pikture_load(const char* filename) {
if (ptr < data_size) { if (ptr < data_size) {
img->pixels[ptr++] = r; img->pixels[ptr++] = r;
img->pixels[ptr++] = g; if (img->channels >= 2) img->pixels[ptr++] = (img->channels == 2) ? a : g;
img->pixels[ptr++] = b; if (img->channels >= 3) img->pixels[ptr++] = b;
img->pixels[ptr++] = a; if (img->channels >= 4) img->pixels[ptr++] = a;
} }
} }
@ -160,16 +157,27 @@ int pikture_save(const char* filename, const pikture_t* img) {
FILE* f = fopen(filename, "wb"); FILE* f = fopen(filename, "wb");
if (!f) return 0; if (!f) return 0;
fwrite(PIKT_MAGIC, 1, 4, f); uint8_t header[11];
uint8_t version = PIKT_VERSION; memcpy(header, PIKT_MAGIC, 4);
fwrite(&version, 1, 1, f); header[4] = PIKT_VERSION;
write_u16_be(f, img->width);
write_u16_be(f, img->height);
uint8_t depth = 32;
fwrite(&depth, 1, 1, f);
uint8_t current_endianness = system_is_be(); uint8_t current_endianness = system_is_be();
fwrite(&current_endianness, 1, 1, f); if (current_endianness) {
header[5] = (img->width >> 8) & 0xFF;
header[6] = img->width & 0xFF;
header[7] = (img->height >> 8) & 0xFF;
header[8] = img->height & 0xFF;
} else {
header[5] = img->width & 0xFF;
header[6] = (img->width >> 8) & 0xFF;
header[7] = img->height & 0xFF;
header[8] = (img->height >> 8) & 0xFF;
}
header[9] = img->depth ? img->depth : (img->channels * 8);
header[10] = current_endianness;
fwrite(header, 1, 11, f);
pikt_pixel index[64] = {0}; pikt_pixel index[64] = {0};
uint8_t prev_r = 0, prev_g = 0, prev_b = 0, prev_a = 255; uint8_t prev_r = 0, prev_g = 0, prev_b = 0, prev_a = 255;
@ -181,11 +189,25 @@ int pikture_save(const char* filename, const pikture_t* img) {
#ifdef PIKT_USE_THREADS #ifdef PIKT_USE_THREADS
#pragma omp parallel #pragma omp parallel
#endif #endif
while (px_idx < total_pixels * 4) { while (px_idx < total_pixels * img->channels) {
uint8_t r = img->pixels[px_idx++]; uint8_t r = 0, g = 0, b = 0, a = 255;
uint8_t g = img->pixels[px_idx++];
uint8_t b = img->pixels[px_idx++]; r = img->pixels[px_idx++];
uint8_t a = img->pixels[px_idx++]; if (img->channels == 4) {
g = img->pixels[px_idx++];
b = img->pixels[px_idx++];
a = img->pixels[px_idx++];
} else if (img->channels == 3) {
g = img->pixels[px_idx++];
b = img->pixels[px_idx++];
} else if (img->channels == 2) {
g = r;
b = r;
a = img->pixels[px_idx++];
} else if (img->channels == 1) {
g = r;
b = r;
}
if (r == prev_r && g == prev_g && b == prev_b && a == prev_a) { if (r == prev_r && g == prev_g && b == prev_b && a == prev_a) {
run++; run++;