source/graphics/imageloader.cpp

   1 #include "imageloader.h"
   2 #include <msp/core/refptr.h>
   3 #include <msp/io/file.h>
   4 #include <msp/strings/format.h>
   5 #include <msp/strings/utils.h>
   6 #include "bmploader.h"
   7 #ifdef WITH_LIBPNG
   8 #include "png/pngloader.h"
   9 #endif
  10 #ifdef WITH_LIBJPEG
  11 #include "jpeg/jpegloader.h"
  12 #endif
  13 #ifdef WITH_DEVIL
  14 #include "devil/devilloader.h"
  15 #endif
  16 #ifdef WITH_QUARTZ
  17 #include "quartz/quartzloader.h"
  18 #endif
  19
  20 using namespace std;
  21
  22 namespace Msp {
  23 namespace Graphics {
  24
  25 ImageLoader::ImageLoader():
  26         source(0),
  27         state(INITIAL)
  28 { }
  29
  30 ImageLoader::~ImageLoader()
  31 {
  32         delete source;
  33 }
  34
  35 bool ImageLoader::detect_signature(const std::string &sig)
  36 {
  37         Registry &registry = get_registry();
  38         for(const RegisterBase *r: registry.loaders)
  39                 if(r->detect(sig))
  40                         return true;
  41         return false;
  42 }
  43
  44 ImageLoader *ImageLoader::open_file(const string &fn)
  45 {
  46         try
  47         {
  48                 RefPtr<IO::BufferedFile> file = new IO::BufferedFile(fn);
  49                 ImageLoader *loader = open_io(*file);
  50                 loader->source = file.release();
  51                 return loader;
  52         }
  53         catch(const unsupported_image_format &e)
  54         {
  55                 throw unsupported_image_format(format("%s: %s", fn, e.what()));
  56         }
  57 }
  58
  59 ImageLoader *ImageLoader::open_io(IO::Seekable &io)
  60 {
  61         Registry &registry = get_registry();
  62         if(registry.changed)
  63         {
  64                 registry.changed = false;
  65                 registry.loaders.sort(signature_size_compare);
  66         }
  67
  68         if(registry.loaders.empty())
  69                 throw unsupported_image_format("no loaders");
  70
  71         string signature(registry.loaders.back()->get_signature_size(), 0);
  72         unsigned sig_len = io.read(&signature[0], signature.size());
  73
  74         ImageLoader *loader = 0;
  75         for(auto i=registry.loaders.begin(); (!loader && i!=registry.loaders.end()); ++i)
  76                 if((*i)->detect(signature))
  77                         loader = (*i)->create(io);
  78
  79         io.seek(0, IO::S_BEG);
  80
  81         if(!loader)
  82         {
  83                 string sig_hex;
  84                 for(unsigned i=0; i<sig_len; ++i)
  85                         append(sig_hex, " ", format("%02X", static_cast<unsigned char>(signature[i])));
  86                 throw unsupported_image_format(sig_hex);
  87         }
  88
  89         return loader;
  90 }
  91
  92 void ImageLoader::load(Image::Data &data)
  93 {
  94         if(state>=FINISHED)
  95                 throw logic_error("already loaded");
  96
  97         if(state<HEADERS_LOADED)
  98                 load_headers_(data);
  99         if(!data.pixels)
 100                 data.pixels = data.owned_pixels = new char[data.stride*data.height];
 101         load_pixels_(data);
 102         state = FINISHED;
 103 }
 104
 105 void ImageLoader::load_headers(Image::Data &data)
 106 {
 107         if(state>=HEADERS_LOADED)
 108                 throw logic_error("headers already loaded");
 109
 110         load_headers_(data);
 111         state = HEADERS_LOADED;
 112 }
 113
 114 ImageLoader::Registry &ImageLoader::get_registry()
 115 {
 116         static Registry registry;
 117         static bool initialized = false;
 118         if(!initialized)
 119         {
 120                 initialized = true;
 121                 register_loader<BmpLoader>();
 122 #ifdef WITH_LIBPNG
 123                 register_loader<PngLoader>();
 124 #endif
 125 #ifdef WITH_LIBJPEG
 126                 register_loader<JpegLoader>();
 127 #endif
 128 #ifdef WITH_DEVIL
 129                 register_loader<DevilLoader>();
 130 #endif
 131 #ifdef WITH_QUARTZ
 132                 register_loader<QuartzLoader>();
 133 #endif
 134         }
 135         return registry;
 136 }
 137
 138 bool ImageLoader::signature_size_compare(RegisterBase *r1, RegisterBase *r2)
 139 {
 140         return r1->get_signature_size()<r2->get_signature_size();
 141 }
 142
 143
 144 ImageLoader::Registry::Registry():
 145         changed(false)
 146 { }
 147
 148 ImageLoader::Registry::~Registry()
 149 {
 150         for(auto l: loaders)
 151                 delete l;
 152 }
 153
 154 } // namespace Graphics
 155 } // namespace Msp