source/graphics/imageloader.cpp

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