N64FlashcartMenu/src/menu/png_decoder.c
2023-07-26 18:41:38 +02:00

109 lines
2.8 KiB
C

#include <libspng/spng/spng.h>
#include "path.h"
#include "png_decoder.h"
png_err_t png_decode (char *path, surface_t *image, int max_width, int max_height) {
spng_ctx *ctx;
enum spng_errno err = SPNG_OK;
path_t *file_path;
FILE *file;
size_t image_size;
struct spng_ihdr ihdr;
struct spng_row_info row_info;
uint8_t *row_buffer;
uint16_t *image_buffer;
image->buffer = NULL;
if ((ctx = spng_ctx_new(SPNG_CTX_IGNORE_ADLER32)) == NULL) {
return PNG_ERR_OUT_OF_MEM;
}
if (spng_set_crc_action(ctx, SPNG_CRC_USE, SPNG_CRC_USE) != SPNG_OK) {
spng_ctx_free(ctx);
return PNG_ERR_INT;
}
if (spng_set_image_limits(ctx, max_width, max_height) != SPNG_OK) {
spng_ctx_free(ctx);
return PNG_ERR_INT;
}
file_path = path_init("sd:/");
path_append(file_path, path);
if ((file = fopen(path_get(file_path), "r")) == NULL) {
spng_ctx_free(ctx);
path_free(file_path);
return PNG_ERR_NO_FILE;
}
path_free(file_path);
if (spng_set_png_file(ctx, file) != SPNG_OK) {
spng_ctx_free(ctx);
fclose(file);
return PNG_ERR_INT;
}
if (spng_decoded_image_size(ctx, SPNG_FMT_RGB8, &image_size) != SPNG_OK) {
spng_ctx_free(ctx);
fclose(file);
return PNG_ERR_BAD_FILE;
}
if (spng_decode_image(ctx, NULL, image_size, SPNG_FMT_RGB8, SPNG_DECODE_PROGRESSIVE) != SPNG_OK) {
spng_ctx_free(ctx);
fclose(file);
return PNG_ERR_BAD_FILE;
}
if (spng_get_ihdr(ctx, &ihdr) != SPNG_OK) {
spng_ctx_free(ctx);
fclose(file);
return PNG_ERR_BAD_FILE;
}
*image = surface_alloc(FMT_RGBA16, ihdr.width, ihdr.height);
if (image->buffer == NULL) {
spng_ctx_free(ctx);
fclose(file);
return PNG_ERR_OUT_OF_MEM;
}
if ((row_buffer = malloc(ihdr.width * 3)) == NULL) {
spng_ctx_free(ctx);
fclose(file);
surface_free(image);
return PNG_ERR_OUT_OF_MEM;
}
do {
if ((err = spng_get_row_info(ctx, &row_info)) != SPNG_OK) {
break;
}
err = spng_decode_row(ctx, row_buffer, ihdr.width * 3);
if (err == SPNG_OK || err == SPNG_EOI) {
image_buffer = image->buffer + (row_info.row_num * image->stride);
for (int i = 0; i < ihdr.width * 3; i += 3) {
uint8_t r = row_buffer[i + 0] >> 3;
uint8_t g = row_buffer[i + 1] >> 3;
uint8_t b = row_buffer[i + 2] >> 3;
*image_buffer++ = (r << 11) | (g << 6) | (b << 1) | 1;
}
}
} while (err == SPNG_OK);
spng_ctx_free(ctx);
free(row_buffer);
fclose(file);
if (err != SPNG_EOI) {
surface_free(image);
return PNG_ERR_BAD_FILE;
}
return PNG_OK;
}