source/graphics/imageloader.cpp

   1 #include <msp/core/refptr.h>
   2 #include <msp/io/file.h>
   3 #include <msp/strings/format.h>
   4 #include "bmploader.h"
   5 #include "imageloader.h"
   6 #ifdef WITH_LIBPNG
   7 #include "png/pngloader.h"
   8 #endif
   9 #ifdef WITH_LIBJPEG
  10 #include "jpeg/jpegloader.h"
  11 #endif
  12 #ifdef WITH_DEVIL
  13 #include "devil/devilloader.h"
  14 #endif
  15 #ifdef WITH_QUARTZ
  16 #include "quartz/quartzloader.h"
  17 #endif
  18
  19 using namespace std;
  20
  21 namespace Msp {
  22 namespace Graphics {
  23
  24 bool ImageLoader::registered_loaders_changed = false;
  25
  26 ImageLoader::ImageLoader():
  27         source(0)
  28 { }
  29
  30 ImageLoader::~ImageLoader()
  31 {
  32         delete source;
  33 }
  34
  35 ImageLoader *ImageLoader::open_file(const string &fn)
  36 {
  37         try
  38         {
  39                 RefPtr<IO::BufferedFile> file = new IO::BufferedFile(fn);
  40                 ImageLoader *loader = open_io(*file);
  41                 loader->source = file.release();
  42                 return loader;
  43         }
  44         catch(const unsupported_image_format &e)
  45         {
  46                 throw unsupported_image_format(format("%s: %s", fn, e.what()));
  47         }
  48 }
  49
  50 ImageLoader *ImageLoader::open_io(IO::Seekable &io)
  51 {
  52         (void)RegisteredImageLoader<BmpLoader>::reg;
  53 #ifdef WITH_LIBPNG
  54         (void)RegisteredImageLoader<PngLoader>::reg;
  55 #endif
  56 #ifdef WITH_LIBJPEG
  57         (void)RegisteredImageLoader<JpegLoader>::reg;
  58 #endif
  59 #ifdef WITH_DEVIL
  60         (void)RegisteredImageLoader<DevilLoader>::reg;
  61 #endif
  62 #ifdef WITH_QUARTZ
  63         (void)RegisteredImageLoader<QuartzLoader>::reg;
  64 #endif
  65
  66         list<RegisterBase *> &loaders = get_registered_loaders();
  67         if(registered_loaders_changed)
  68         {
  69                 registered_loaders_changed = false;
  70                 loaders.sort(signature_size_compare);
  71         }
  72
  73         if(loaders.empty())
  74                 throw unsupported_image_format("no loaders");
  75
  76         vector<char> sig_buf(loaders.back()->get_signature_size());
  77         unsigned sig_len = io.read(&sig_buf[0], sig_buf.size());
  78         string signature(sig_buf.begin(), sig_buf.end());
  79
  80         ImageLoader *loader = 0;
  81         for(list<RegisterBase *>::const_iterator i=loaders.begin(); (!loader && i!=loaders.end()); ++i)
  82                 if((*i)->detect(signature))
  83                         loader = (*i)->create(io);
  84
  85         io.seek(0, IO::S_BEG);
  86
  87         if(!loader)
  88         {
  89                 string sig_hex;
  90                 for(unsigned i=0; i<sig_len; ++i)
  91                 {
  92                         if(i)
  93                                 sig_hex += ' ';
  94                         sig_hex += format("%02X", static_cast<unsigned char>(sig_buf[i]));
  95                 }
  96                 throw unsupported_image_format(sig_hex);
  97         }
  98
  99         return loader;
 100 }
 101
 102
 103 ImageLoader::RegisterBase::RegisterBase()
 104 {
 105         get_registered_loaders().push_back(this);
 106         registered_loaders_changed = true;
 107 }
 108
 109
 110 list<ImageLoader::RegisterBase *> &ImageLoader::get_registered_loaders()
 111 {
 112         static list<RegisterBase *> regs;
 113         return regs;
 114 }
 115
 116 bool ImageLoader::signature_size_compare(RegisterBase *r1, RegisterBase *r2)
 117 {
 118         return r1->get_signature_size()<r2->get_signature_size();
 119 }
 120
 121 } // namespace Graphics
 122 } // namespace Msp