void a_png_readFile(const char* path, Pixel** pixels, int* width, int* height)
{
File* const f = a_file_open(path, "r");
png_structp png = NULL;
png_infop info = NULL;
if(!f) {
goto cleanUp;
}
#define PNG_SIG 8
png_byte sig[PNG_SIG];
a_file_read(f, sig, PNG_SIG);
if(png_sig_cmp(sig, 0, PNG_SIG) != 0) {
a_error("%s is not a PNG", path);
goto cleanUp;
}
png = png_create_read_struct(PNG_LIBPNG_VER_STRING, NULL, NULL, NULL);
if(!png) {
goto cleanUp;
}
info = png_create_info_struct(png);
if(!info) {
goto cleanUp;
}
if(setjmp(png_jmpbuf(png))) {
goto cleanUp;
}
png_init_io(png, a_file_handle(f));
png_set_sig_bytes(png, PNG_SIG);
png_read_png(png, info, PNG_TRANSFORM_IDENTITY, NULL);
const int type = png_get_color_type(png, info);
if(type != PNG_COLOR_TYPE_RGB && type != PNG_COLOR_TYPE_RGBA) {
a_error("%s not 8-bit RGBA PNG", path);
goto cleanUp;
}
pngToPixels(png, info, pixels, width, height);
cleanUp:
if(png) {
png_destroy_read_struct(&png, info ? &info : NULL, NULL);
}
if(f) {
a_file_close(f);
}
}
void a_png_write(const char* path, const Pixel* data, int width, int height)
{
File* f = a_file_open(path, "w");
png_structp png = NULL;
png_infop info = NULL;
png_bytepp rows = NULL;
if(!f) {
goto cleanUp;
}
rows = malloc(height * sizeof(png_bytep));
memset(rows, 0, height * sizeof(png_bytep));
png = png_create_write_struct(PNG_LIBPNG_VER_STRING, NULL, NULL, NULL);
if(!png) {
goto cleanUp;
}
info = png_create_info_struct(png);
if(!info) {
goto cleanUp;
}
if(setjmp(png_jmpbuf(png))) {
goto cleanUp;
}
png_set_compression_level(png, Z_BEST_COMPRESSION);
png_set_IHDR(
png, info,
width, height,
8, PNG_COLOR_TYPE_RGB,
PNG_INTERLACE_NONE, PNG_COMPRESSION_TYPE_DEFAULT,
PNG_FILTER_TYPE_DEFAULT
);
for(int i = 0; i < height; i++) {
rows[i] = malloc(width * 3 * sizeof(png_byte));
for(int j = 0; j < width; j++) {
const Pixel p = *(data + i * width + j);
rows[i][j * 3 + 0] = a_pixel_red(p);
rows[i][j * 3 + 1] = a_pixel_green(p);
rows[i][j * 3 + 2] = a_pixel_blue(p);
}
}
png_init_io(png, a_file_handle(f));
png_set_rows(png, info, rows);
png_write_png(png, info, PNG_TRANSFORM_IDENTITY, NULL);
png_write_end(png, NULL);
cleanUp:
if(png) {
png_destroy_write_struct(&png, info ? &info : NULL);
}
if(rows) {
for(int i = 0; i < height; i++) {
free(rows[i]);
}
free(rows);
}
if(f) {
a_file_close(f);
}
}
void a_png_write(const char* Path, const APixel* Data, int Width, int Height, char* Title, char* Description)
{
AFile* f = a_file_open(Path, "wb");
png_structp png = NULL;
png_infop info = NULL;
png_bytepp rows = NULL;
png_text text[2];
int numText = 0;
if(!f) {
goto cleanUp;
}
rows = a_mem_malloc(Height * sizeof(png_bytep));
memset(rows, 0, Height * sizeof(png_bytep));
png = png_create_write_struct(PNG_LIBPNG_VER_STRING, NULL, NULL, NULL);
if(!png) {
goto cleanUp;
}
info = png_create_info_struct(png);
if(!info) {
goto cleanUp;
}
if(setjmp(png_jmpbuf(png))) {
goto cleanUp;
}
png_set_compression_level(png, Z_BEST_COMPRESSION);
png_set_IHDR(
png, info,
Width, Height,
8, PNG_COLOR_TYPE_RGB,
PNG_INTERLACE_NONE, PNG_COMPRESSION_TYPE_DEFAULT,
PNG_FILTER_TYPE_DEFAULT
);
for(int i = 0; i < Height; i++) {
rows[i] = a_mem_malloc(Width * 3 * sizeof(png_byte));
for(int j = 0; j < Width; j++) {
const APixel p = *(Data + i * Width + j);
rows[i][j * 3 + 0] = a_pixel_red(p);
rows[i][j * 3 + 1] = a_pixel_green(p);
rows[i][j * 3 + 2] = a_pixel_blue(p);
}
}
if(Title != NULL) {
text[numText].compression = PNG_TEXT_COMPRESSION_NONE;
text[numText].key = "Title";
text[numText].text = Title;
numText++;
}
if(Description != NULL) {
text[numText].compression = PNG_TEXT_COMPRESSION_NONE;
text[numText].key = "Description";
text[numText].text = Description;
numText++;
}
png_init_io(png, a_file_handle(f));
png_set_rows(png, info, rows);
png_set_text(png, info, text, numText);
png_write_png(png, info, PNG_TRANSFORM_IDENTITY, NULL);
png_write_end(png, NULL);
cleanUp:
if(png) {
png_destroy_write_struct(&png, info ? &info : NULL);
}
if(rows) {
for(int i = 0; i < Height; i++) {
free(rows[i]);
}
free(rows);
}
if(f) {
a_file_close(f);
}
}