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, signature_size_compare);
  62         }
  63
  64         if(registry.loaders.empty())
  65                 throw unsupported_image_format("no loaders");
  66
  67         string signature(registry.loaders.back()->get_signature_size(), 0);
  68         unsigned sig_len = io.read(&signature[0], signature.size());
  69
  70         ImageLoader *loader = nullptr;
  71         for(auto i=registry.loaders.begin(); (!loader && i!=registry.loaders.end()); ++i)
  72                 if((*i)->detect(signature))
  73                         loader = (*i)->create(io);
  74
  75         io.seek(0, IO::S_BEG);
  76
  77         if(!loader)
  78         {
  79                 string sig_hex;
  80                 for(unsigned i=0; i<sig_len; ++i)
  81                         append(sig_hex, " ", format("%02X", static_cast<unsigned char>(signature[i])));
  82                 throw unsupported_image_format(sig_hex);
  83         }
  84
  85         return loader;
  86 }
  87
  88 void ImageLoader::load(Image::Data &data)
  89 {
  90         if(state>=FINISHED)
  91                 throw logic_error("already loaded");
  92
  93         if(state<HEADERS_LOADED)
  94                 load_headers_(data);
  95         if(!data.pixels)
  96                 data.pixels = data.owned_pixels = new char[data.stride*data.height];
  97         load_pixels_(data);
  98         state = FINISHED;
  99 }
 100
 101 void ImageLoader::load_headers(Image::Data &data)
 102 {
 103         if(state>=HEADERS_LOADED)
 104                 throw logic_error("headers already loaded");
 105
 106         load_headers_(data);
 107         state = HEADERS_LOADED;
 108 }
 109
 110 ImageLoader::Registry &ImageLoader::get_registry()
 111 {
 112         static Registry registry;
 113         static bool initialized = false;
 114         if(!initialized)
 115         {
 116                 initialized = true;
 117                 register_loader<BmpLoader>();
 118 #ifdef WITH_LIBPNG
 119                 register_loader<PngLoader>();
 120 #endif
 121 #ifdef WITH_LIBJPEG
 122                 register_loader<JpegLoader>();
 123 #endif
 124 #ifdef WITH_DEVIL
 125                 register_loader<DevilLoader>();
 126 #endif
 127 #ifdef WITH_QUARTZ
 128                 register_loader<QuartzLoader>();
 129 #endif
 130         }
 131         return registry;
 132 }
 133
 134 bool ImageLoader::signature_size_compare(RegisterBase *r1, RegisterBase *r2)
 135 {
 136         return r1->get_signature_size()<r2->get_signature_size();
 137 }
 138
 139
 140 ImageLoader::Registry::~Registry()
 141 {
 142         for(auto l: loaders)
 143                 delete l;
 144 }
 145
 146 } // namespace Graphics
 147 } // namespace Msp