bool open(const std::experimental::filesystem::path& jpeg_file) override
{
auto fp = ::fopen(to_osmbstr(to_utf8(jpeg_file.native())).c_str(), "rb");
if(nullptr == fp) return false;
bool is_opened = false;
struct ::jpeg_decompress_struct jdstru;
error_mgr jerr;
jdstru.err = ::jpeg_std_error(&jerr.pub);
jerr.pub.error_exit = _m_error_handler;
if (!setjmp(jerr.setjmp_buf))
{
::jpeg_create_decompress(&jdstru);
::jpeg_stdio_src(&jdstru, fp);
_m_read_jpg(jdstru);
jpeg_finish_decompress(&jdstru);
is_opened = true;
}
::jpeg_destroy_decompress(&jdstru);
::fclose(fp);
return is_opened;
}
std::shared_ptr<image::image_impl_interface> create_image(const fs::path & p)
{
std::shared_ptr<image::image_impl_interface> ptr;
auto ext = p.extension().native();
if (ext.empty())
return ptr;
std::transform(ext.begin(), ext.end(), ext.begin(), [](int ch)
{
if ('A' <= ch && ch <= 'Z')
ch -= ('A' - 'a');
return ch;
});
#if defined(NANA_WINDOWS)
const wchar_t* ext_ico = L".ico";
const wchar_t* ext_png = L".png";
const wchar_t* ext_jpg = L".jpg";
const wchar_t* ext_jpeg = L".jpeg";
#else
const char* ext_ico = ".ico";
const char* ext_png = ".png";
const char* ext_jpg = ".jpg";
const char* ext_jpeg = ".jpeg";
#endif
do
{
if (ext_ico == ext)
{
ptr = std::make_shared<detail::image_ico>();
break;
}
if (ext_png == ext)
{
#if defined(NANA_ENABLE_PNG)
ptr = std::make_shared<detail::image_png>();
#else
return ptr;
#endif
break;
}
if (ext_jpg == ext || ext_jpeg == ext)
{
#if defined(NANA_ENABLE_JPEG)
ptr = std::make_shared<detail::image_jpeg>();
#else
return ptr;
#endif
break;
}
} while (false);
//Check for BMP
if (!ptr)
{
#ifndef NANA_MINGW
std::ifstream ifs(p.c_str(), std::ios::binary);
#else
std::ifstream ifs(to_osmbstr(to_utf8(p.native())).c_str(), std::ios::binary);
#endif
if (ifs)
{
unsigned short meta = 0;
ifs.read(reinterpret_cast<char*>(&meta), 2);
if (*reinterpret_cast<const short*>("BM") == meta)
ptr = std::make_shared<detail::image_bmp>();
else if (*reinterpret_cast<const short*>("MZ") == meta)
ptr = std::make_shared<detail::image_ico_resource>();
}
}
return ptr;
}