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#include "tinyff/image/png.h"
#include "png.h"
ff_result ff_png_isvalid(FILE *file)
{
char raw_sig[8];
if (fread(raw_sig, sizeof(char), 8, file) != 8) {
// Unable to read first 8 bytes
return FF_RESULT_ERROR_INVALID_FILE;
}
if (memcmp(raw_sig, PNG_SIGNATURE, 8) != 0) {
// Signature did not match
return FF_RESULT_ERROR_INVALID_FILE_SIGNITURE;
}
return FF_RESULT_OK;
}
ff_result ff_open_png(const char *filepath, ff_png_ctx **out_ctx) {
// Validate
ff_png_ctx ctx;
ctx.raw = fopen(filepath, "rb");
if (!ctx.raw) {
return FF_RESULT_ERROR_READ_FILE_FAILURE;
}
if (ff_png_isvalid(ctx.raw) != FF_RESULT_OK) {
return ff_png_isvalid(ctx.raw);
}
// This is a heavy W.I.P
}
void ff_png_header_handler(uint8_t *data, size_t len, ff_png_ctx *ctx)
{
if (len != 13) return; // Invalid length
printf("Width: %d\n", get_big_endian(data));
printf("Height: %d\n", get_big_endian(data + 4));
printf("Bit depth: %d\n", (unsigned char)data[8]);
printf("Color type: %d\n", (unsigned char)data[9]);
printf("Compression method: %d\n", (unsigned char)data[10]);
printf("Filter method: %d\n", (unsigned char)data[11]);
printf("Interlace method: %d\n", (unsigned char)data[12]);
// Store in context
ctx->width = get_big_endian(data);
ctx->height = get_big_endian(data + 4);
ctx->bit_depth = (unsigned char)data[8];
ctx->color_type = (unsigned char)data[9];
}
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