static int stbi__jpeg_test(stbi__context *s)
{
   int r;
   stbi__jpeg* j = (stbi__jpeg*)stbi__malloc(sizeof(stbi__jpeg));
   if (!j) return stbi__err("outofmem", "Out of memory");
   j->s = s;
   stbi__setup_jpeg(j);
   r = stbi__decode_jpeg_header(j, STBI__SCAN_type);
   stbi__rewind(s);
   STBI_FREE(j);
   return r;
}
Unknown