boost/gil/extension/io/jpeg/detail/read.hpp

   1 //
   2 // Copyright 2007-2012 Christian Henning, Andreas Pokorny, Lubomir Bourdev
   3 //
   4 // Distributed under the Boost Software License, Version 1.0
   5 // See accompanying file LICENSE_1_0.txt or copy at
   6 // http://www.boost.org/LICENSE_1_0.txt
   7 //
   8 #ifndef BOOST_GIL_EXTENSION_IO_JPEG_DETAIL_READ_HPP
   9 #define BOOST_GIL_EXTENSION_IO_JPEG_DETAIL_READ_HPP
  10
  11 #include <boost/gil/extension/io/jpeg/tags.hpp>
  12 #include <boost/gil/extension/io/jpeg/detail/base.hpp>
  13 #include <boost/gil/extension/io/jpeg/detail/is_allowed.hpp>
  14
  15 #include <boost/gil/io/base.hpp>
  16 #include <boost/gil/io/conversion_policies.hpp>
  17 #include <boost/gil/io/device.hpp>
  18 #include <boost/gil/io/dynamic_io_new.hpp>
  19 #include <boost/gil/io/reader_base.hpp>
  20 #include <boost/gil/io/typedefs.hpp>
  21
  22 #include <csetjmp>
  23 #include <type_traits>
  24 #include <vector>
  25
  26 namespace boost { namespace gil {
  27
  28 #if BOOST_WORKAROUND(BOOST_MSVC, >= 1400)
  29 #pragma warning(push)
  30 #pragma warning(disable:4512) //assignment operator could not be generated
  31 #pragma warning(disable:4611) //interaction between '_setjmp' and C++ object destruction is non-portable
  32 #endif
  33
  34 ///
  35 /// JPEG Reader
  36 ///
  37 template< typename Device
  38         , typename ConversionPolicy
  39         >
  40 class reader< Device
  41             , jpeg_tag
  42             , ConversionPolicy
  43             >
  44     : public reader_base< jpeg_tag
  45                         , ConversionPolicy
  46                         >
  47     , public reader_backend< Device
  48                            , jpeg_tag
  49                            >
  50 {
  51 private:
  52
  53     using this_t = reader<Device, jpeg_tag, ConversionPolicy>;
  54     using cc_t = typename ConversionPolicy::color_converter_type;
  55
  56 public:
  57
  58     using backend_t = reader_backend<Device, jpeg_tag>;
  59
  60 public:
  61
  62     //
  63     // Constructor
  64     //
  65     reader( const Device&                          io_dev
  66           , const image_read_settings< jpeg_tag >& settings
  67           )
  68     : reader_base< jpeg_tag
  69                  , ConversionPolicy
  70                  >()
  71
  72     , backend_t( io_dev
  73                , settings
  74                )
  75     {}
  76
  77     //
  78     // Constructor
  79     //
  80     reader( const Device&                                          io_dev
  81           , const typename ConversionPolicy::color_converter_type& cc
  82           , const image_read_settings< jpeg_tag >&                 settings
  83           )
  84     : reader_base< jpeg_tag
  85                  , ConversionPolicy
  86                  >( cc )
  87     , backend_t( io_dev
  88                , settings
  89                )
  90     {}
  91
  92     template<typename View>
  93     void apply( const View& view )
  94     {
  95         // Fire exception in case of error.
  96         if( setjmp( this->_mark ))
  97         {
  98             this->raise_error();
  99         }
 100
 101         this->get()->dct_method = this->_settings._dct_method;
 102
 103         using is_read_and_convert_t = typename std::is_same
 104             <
 105                 ConversionPolicy,
 106                 detail::read_and_no_convert
 107             >::type;
 108
 109         io_error_if( !detail::is_allowed< View >( this->_info
 110                                                 , is_read_and_convert_t()
 111                                                 )
 112                    , "Image types aren't compatible."
 113                    );
 114
 115         if( jpeg_start_decompress( this->get() ) == false )
 116         {
 117             io_error( "Cannot start decompression." );
 118         }
 119
 120         switch( this->_info._color_space )
 121         {
 122             case JCS_GRAYSCALE:
 123             {
 124                 this->_scanline_length = this->_info._width;
 125                 read_rows< gray8_pixel_t >( view );
 126
 127                 break;
 128             }
 129
 130             case JCS_RGB:
 131             //!\todo add Y'CbCr? We loose image quality when reading JCS_YCbCr as JCS_RGB
 132             case JCS_YCbCr:
 133             {
 134                 this->_scanline_length = this->_info._width * num_channels< rgb8_view_t >::value;
 135
 136                 read_rows< rgb8_pixel_t  >( view );
 137                 break;
 138             }
 139
 140             case JCS_CMYK:
 141             //!\todo add Y'CbCrK? We loose image quality when reading JCS_YCCK as JCS_CMYK
 142             case JCS_YCCK:
 143             {
 144                 this->get()->out_color_space = JCS_CMYK;
 145                 this->_scanline_length = this->_info._width * num_channels< cmyk8_view_t >::value;
 146
 147                 read_rows< cmyk8_pixel_t >( view );
 148
 149                 break;
 150             }
 151             default: { io_error( "Unsupported jpeg color space." ); }
 152         }
 153
 154         jpeg_finish_decompress ( this->get() );
 155     }
 156
 157 private:
 158
 159     template< typename ImagePixel
 160             , typename View
 161             >
 162     void read_rows( const View& view )
 163     {
 164         using buffer_t = std::vector<ImagePixel>;
 165         buffer_t buffer( this->_info._width );
 166
 167         // In case of an error we'll jump back to here and fire an exception.
 168         // @todo Is the buffer above cleaned up when the exception is thrown?
 169         //       The strategy right now is to allocate necessary memory before
 170         //       the setjmp.
 171         if( setjmp( this->_mark ))
 172         {
 173             this->raise_error();
 174         }
 175
 176
 177         JSAMPLE *row_adr = reinterpret_cast< JSAMPLE* >( &buffer[0] );
 178
 179         //Skip scanlines if necessary.
 180         for( int y = 0; y <  this->_settings._top_left.y; ++y )
 181         {
 182             io_error_if( jpeg_read_scanlines( this->get()
 183                                             , &row_adr
 184                                             , 1
 185                                             ) !=1
 186                        , "jpeg_read_scanlines: fail to read JPEG file"
 187                        );
 188         }
 189
 190         // Read data.
 191         for( int y = 0; y < view.height(); ++y )
 192         {
 193             io_error_if( jpeg_read_scanlines( this->get()
 194                                             , &row_adr
 195                                             , 1
 196                                             ) != 1
 197                        , "jpeg_read_scanlines: fail to read JPEG file"
 198                        );
 199
 200             typename buffer_t::iterator beg = buffer.begin() + this->_settings._top_left.x;
 201             typename buffer_t::iterator end = beg + this->_settings._dim.x;
 202
 203             this->_cc_policy.read( beg
 204                                  , end
 205                                  , view.row_begin( y )
 206                                  );
 207         }
 208
 209         //@todo: There might be a better way to do that.
 210         while( this->get()->output_scanline < this->get()->image_height )
 211         {
 212             io_error_if( jpeg_read_scanlines( this->get()
 213                                             , &row_adr
 214                                             , 1
 215                                             ) !=1
 216                        , "jpeg_read_scanlines: fail to read JPEG file"
 217                        );
 218         }
 219
 220     }
 221 };
 222
 223 namespace detail {
 224
 225 struct jpeg_type_format_checker
 226 {
 227     jpeg_type_format_checker( jpeg_color_space::type color_space )
 228     : _color_space( color_space )
 229     {}
 230
 231     template< typename Image >
 232     bool apply()
 233     {
 234         return is_read_supported< typename get_pixel_type< typename Image::view_t >::type
 235                                 , jpeg_tag
 236                                 >::_color_space == _color_space;
 237     }
 238
 239 private:
 240
 241     jpeg_color_space::type _color_space;
 242 };
 243
 244 struct jpeg_read_is_supported
 245 {
 246     template< typename View >
 247     struct apply : public is_read_supported< typename get_pixel_type< View >::type
 248                                            , jpeg_tag
 249                                            >
 250     {};
 251 };
 252
 253 } // namespace detail
 254
 255 ///
 256 /// JPEG Dynamic Reader
 257 ///
 258 template< typename Device >
 259 class dynamic_image_reader< Device
 260                           , jpeg_tag
 261                           >
 262     : public reader< Device
 263                    , jpeg_tag
 264                    , detail::read_and_no_convert
 265                    >
 266 {
 267     using parent_t = reader<Device, jpeg_tag, detail::read_and_no_convert>;
 268
 269 public:
 270
 271     dynamic_image_reader( const Device&                          io_dev
 272                         , const image_read_settings< jpeg_tag >& settings
 273                         )
 274     : parent_t( io_dev
 275               , settings
 276               )
 277     {}
 278
 279     template< typename Images >
 280     void apply( any_image< Images >& images )
 281     {
 282         detail::jpeg_type_format_checker format_checker( this->_info._color_space != JCS_YCbCr
 283                                                        ? this->_info._color_space
 284                                                        : JCS_RGB
 285                                                        );
 286
 287         if( !construct_matched( images
 288                               , format_checker
 289                               ))
 290         {
 291             io_error( "No matching image type between those of the given any_image and that of the file" );
 292         }
 293         else
 294         {
 295             this->init_image( images
 296                             , this->_settings
 297                             );
 298
 299             detail::dynamic_io_fnobj< detail::jpeg_read_is_supported
 300                                     , parent_t
 301                                     > op( this );
 302
 303             apply_operation( view( images )
 304                            , op
 305                            );
 306         }
 307     }
 308 };
 309
 310 #if BOOST_WORKAROUND(BOOST_MSVC, >= 1400)
 311 #pragma warning(pop)
 312 #endif
 313
 314 } // gil
 315 } // boost
 316
 317 #endif