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

   1 //
   2 // Copyright 2012 Christian Henning
   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_PNM_DETAIL_READ_HPP
   9 #define BOOST_GIL_EXTENSION_IO_PNM_DETAIL_READ_HPP
  10
  11 #include <boost/gil/extension/io/pnm/tags.hpp>
  12 #include <boost/gil/extension/io/pnm/detail/reader_backend.hpp>
  13 #include <boost/gil/extension/io/pnm/detail/is_allowed.hpp>
  14
  15 #include <boost/gil.hpp> // FIXME: Include what you use!
  16 #include <boost/gil/io/base.hpp>
  17 #include <boost/gil/io/bit_operations.hpp>
  18 #include <boost/gil/io/conversion_policies.hpp>
  19 #include <boost/gil/io/device.hpp>
  20 #include <boost/gil/io/dynamic_io_new.hpp>
  21 #include <boost/gil/io/reader_base.hpp>
  22 #include <boost/gil/io/row_buffer_helper.hpp>
  23 #include <boost/gil/io/typedefs.hpp>
  24
  25 #include <type_traits>
  26 #include <vector>
  27
  28 namespace boost { namespace gil {
  29
  30 #if BOOST_WORKAROUND(BOOST_MSVC, >= 1400)
  31 #pragma warning(push)
  32 #pragma warning(disable:4512) //assignment operator could not be generated
  33 #endif
  34
  35 ///
  36 /// PNM Reader
  37 ///
  38 template< typename Device
  39         , typename ConversionPolicy
  40         >
  41 class reader< Device
  42             , pnm_tag
  43             , ConversionPolicy
  44             >
  45     : public reader_base< pnm_tag
  46                         , ConversionPolicy
  47                         >
  48     , public reader_backend< Device
  49                            , pnm_tag
  50                            >
  51 {
  52
  53 private:
  54
  55     using this_t = reader<Device, pnm_tag, ConversionPolicy>;
  56     using cc_t = typename ConversionPolicy::color_converter_type;
  57
  58 public:
  59
  60     using backend_t = reader_backend<Device, pnm_tag>;
  61
  62     reader( const Device&                         io_dev
  63           , const image_read_settings< pnm_tag >& settings
  64           )
  65     : reader_base< pnm_tag
  66                  , ConversionPolicy
  67                  >()
  68     , backend_t( io_dev
  69                , settings
  70                )
  71     {}
  72
  73     reader( const Device&                         io_dev
  74           , const cc_t&                           cc
  75           , const image_read_settings< pnm_tag >& settings
  76           )
  77     : reader_base< pnm_tag
  78                  , ConversionPolicy
  79                  >( cc )
  80     , backend_t( io_dev
  81                , settings
  82                )
  83     {}
  84
  85     template<typename View>
  86     void apply( const View& view )
  87     {
  88         using is_read_and_convert_t = typename std::is_same
  89             <
  90                 ConversionPolicy,
  91                 detail::read_and_no_convert
  92             >::type;
  93
  94         io_error_if( !detail::is_allowed< View >( this->_info
  95                                                 , is_read_and_convert_t()
  96                                                 )
  97                    , "Image types aren't compatible."
  98                    );
  99
 100         switch( this->_info._type )
 101         {
 102             // reading mono text is reading grayscale but with only two values
 103             case pnm_image_type::mono_asc_t::value:
 104             case pnm_image_type::gray_asc_t::value:
 105             {
 106                 this->_scanline_length = this->_info._width;
 107
 108                 read_text_data< gray8_view_t >( view );
 109
 110                 break;
 111             }
 112
 113             case pnm_image_type::color_asc_t::value:
 114             {
 115                 this->_scanline_length = this->_info._width * num_channels< rgb8_view_t >::value;
 116
 117                 read_text_data< rgb8_view_t  >( view );
 118
 119                 break;
 120             }
 121
 122             case pnm_image_type::mono_bin_t::value:
 123             {
 124                 //gray1_image_t
 125                 this->_scanline_length = ( this->_info._width + 7 ) >> 3;
 126
 127                 read_bin_data< gray1_image_t::view_t >( view );
 128
 129                 break;
 130             }
 131
 132             case pnm_image_type::gray_bin_t::value:
 133             {
 134                 // gray8_image_t
 135                 this->_scanline_length = this->_info._width;
 136
 137                 read_bin_data< gray8_view_t >( view );
 138
 139                 break;
 140             }
 141
 142             case pnm_image_type::color_bin_t::value:
 143             {
 144                 // rgb8_image_t
 145                 this->_scanline_length = this->_info._width * num_channels< rgb8_view_t >::value;
 146
 147                 read_bin_data< rgb8_view_t >( view );
 148                 break;
 149             }
 150         }
 151     }
 152
 153 private:
 154
 155     template< typename View_Src
 156             , typename View_Dst
 157             >
 158     void read_text_data( const View_Dst& dst )
 159     {
 160         using y_t = typename View_Dst::y_coord_t;
 161
 162         byte_vector_t row( this->_scanline_length );
 163
 164         //Skip scanlines if necessary.
 165         for( int y = 0; y <  this->_settings._top_left.y; ++y )
 166         {
 167             read_text_row< View_Src >( dst, row, y, false );
 168         }
 169
 170         for( y_t y = 0; y < dst.height(); ++y )
 171         {
 172             read_text_row< View_Src >( dst, row, y, true );
 173         }
 174     }
 175
 176     template< typename View_Src
 177             , typename View_Dst
 178             >
 179     void read_text_row( const View_Dst&              dst
 180                       , byte_vector_t&               row
 181                       , typename View_Dst::y_coord_t y
 182                       , bool                         process
 183                       )
 184     {
 185         View_Src src = interleaved_view( this->_info._width
 186                                        , 1
 187                                        , (typename View_Src::value_type*) &row.front()
 188                                        , this->_scanline_length
 189                                        );
 190
 191         for( uint32_t x = 0; x < this->_scanline_length; ++x )
 192         {
 193             for( uint32_t k = 0; ; )
 194             {
 195                 int ch = this->_io_dev.getc_unchecked();
 196
 197                 if( isdigit( ch ))
 198                 {
 199                     buf[ k++ ] = static_cast< char >( ch );
 200                 }
 201                 else if( k )
 202                 {
 203                     buf[ k ] = 0;
 204                     break;
 205                 }
 206                 else if( ch == EOF || !isspace( ch ))
 207                 {
 208                     return;
 209                 }
 210             }
 211
 212             if( process )
 213             {
 214                 int value = atoi( buf );
 215
 216                 if( this->_info._max_value == 1 )
 217                 {
 218                     using channel_t = typename channel_type<typename get_pixel_type<View_Dst>::type>::type;
 219
 220                     // for pnm format 0 is white
 221                     row[x] = ( value != 0 )
 222                              ? typename channel_traits< channel_t >::value_type( 0 )
 223                              : channel_traits< channel_t >::max_value();
 224                 }
 225                 else
 226                 {
 227                     row[x] = static_cast< byte_t >( value );
 228                 }
 229             }
 230         }
 231
 232         if( process )
 233         {
 234             // We are reading a gray1_image like a gray8_image but the two pixel_t
 235             // aren't compatible. Though, read_and_no_convert::read(...) wont work.
 236             copy_data< View_Dst
 237                      , View_Src >( dst
 238                                  , src
 239                                  , y
 240                                  , typename std::is_same< View_Dst
 241                                                    , gray1_image_t::view_t
 242                                                    >::type()
 243                                  );
 244         }
 245     }
 246
 247     template< typename View_Dst
 248             , typename View_Src
 249             >
 250     void copy_data( const View_Dst&              dst
 251                   , const View_Src&              src
 252                   , typename View_Dst::y_coord_t y
 253                   , std::true_type // is gray1_view
 254                   )
 255     {
 256         if(  this->_info._max_value == 1 )
 257         {
 258             typename View_Dst::x_iterator it = dst.row_begin( y );
 259
 260             for( typename View_Dst::x_coord_t x = 0
 261                ; x < dst.width()
 262                ; ++x
 263                )
 264             {
 265                 it[x] = src[x];
 266             }
 267         }
 268         else
 269         {
 270             copy_data(dst, src, y, std::false_type{});
 271         }
 272     }
 273
 274     template< typename View_Dst
 275             , typename View_Src
 276             >
 277     void copy_data( const View_Dst&              view
 278                   , const View_Src&              src
 279                   , typename View_Dst::y_coord_t y
 280                   , std::false_type // is gray1_view
 281                   )
 282     {
 283         typename View_Src::x_iterator beg = src.row_begin( 0 ) + this->_settings._top_left.x;
 284         typename View_Src::x_iterator end = beg + this->_settings._dim.x;
 285
 286         this->_cc_policy.read( beg
 287                              , end
 288                              , view.row_begin( y )
 289                              );
 290     }
 291
 292
 293     template< typename View_Src
 294             , typename View_Dst
 295             >
 296     void read_bin_data( const View_Dst& view )
 297     {
 298         using y_t = typename View_Dst::y_coord_t;
 299         using is_bit_aligned_t = typename is_bit_aligned<typename View_Src::value_type>::type;
 300
 301         using rh_t = detail::row_buffer_helper_view<View_Src>;
 302         rh_t rh( this->_scanline_length, true );
 303
 304         typename rh_t::iterator_t beg = rh.begin() + this->_settings._top_left.x;
 305         typename rh_t::iterator_t end = beg + this->_settings._dim.x;
 306
 307         // For bit_aligned images we need to negate all bytes in the row_buffer
 308         // to make sure that 0 is black and 255 is white.
 309         detail::negate_bits
 310             <
 311                 typename rh_t::buffer_t,
 312                 std::integral_constant<bool, is_bit_aligned_t::value> // TODO: Simplify after MPL removal
 313             > neg;
 314
 315         detail::swap_half_bytes
 316             <
 317                 typename rh_t::buffer_t,
 318                 std::integral_constant<bool, is_bit_aligned_t::value> // TODO: Simplify after MPL removal
 319             > swhb;
 320
 321         //Skip scanlines if necessary.
 322         for( y_t y = 0; y < this->_settings._top_left.y; ++y )
 323         {
 324             this->_io_dev.read( reinterpret_cast< byte_t* >( rh.data() )
 325                         , this->_scanline_length
 326                         );
 327         }
 328
 329         for( y_t y = 0; y < view.height(); ++y )
 330         {
 331             this->_io_dev.read( reinterpret_cast< byte_t* >( rh.data() )
 332                         , this->_scanline_length
 333                         );
 334
 335             neg( rh.buffer() );
 336             swhb( rh.buffer() );
 337
 338             this->_cc_policy.read( beg
 339                                  , end
 340                                  , view.row_begin( y )
 341                                  );
 342         }
 343     }
 344
 345 private:
 346
 347     char buf[16];
 348
 349 };
 350
 351
 352 namespace detail {
 353
 354 struct pnm_type_format_checker
 355 {
 356     pnm_type_format_checker( pnm_image_type::type type )
 357     : _type( type )
 358     {}
 359
 360     template< typename Image >
 361     bool apply()
 362     {
 363         using is_supported_t = is_read_supported
 364             <
 365                 typename get_pixel_type<typename Image::view_t>::type,
 366                 pnm_tag
 367             >;
 368
 369         return is_supported_t::_asc_type == _type
 370             || is_supported_t::_bin_type == _type;
 371     }
 372
 373 private:
 374
 375     pnm_image_type::type _type;
 376 };
 377
 378 struct pnm_read_is_supported
 379 {
 380     template< typename View >
 381     struct apply : public is_read_supported< typename get_pixel_type< View >::type
 382                                            , pnm_tag
 383                                            >
 384     {};
 385 };
 386
 387 } // namespace detail
 388
 389 ///
 390 /// PNM Dynamic Image Reader
 391 ///
 392 template< typename Device
 393         >
 394 class dynamic_image_reader< Device
 395                           , pnm_tag
 396                           >
 397     : public reader< Device
 398                    , pnm_tag
 399                    , detail::read_and_no_convert
 400                    >
 401 {
 402     using parent_t = reader
 403         <
 404             Device,
 405             pnm_tag,
 406             detail::read_and_no_convert
 407         >;
 408
 409 public:
 410
 411     dynamic_image_reader( const Device&                         io_dev
 412                         , const image_read_settings< pnm_tag >& settings
 413                         )
 414     : parent_t( io_dev
 415               , settings
 416               )
 417     {}
 418
 419     template< typename Images >
 420     void apply( any_image< Images >& images )
 421     {
 422         detail::pnm_type_format_checker format_checker( this->_info._type );
 423
 424         if( !construct_matched( images
 425                               , format_checker
 426                               ))
 427         {
 428             io_error( "No matching image type between those of the given any_image and that of the file" );
 429         }
 430         else
 431         {
 432             this->init_image( images
 433                             , this->_settings
 434                             );
 435
 436             detail::dynamic_io_fnobj< detail::pnm_read_is_supported
 437                                     , parent_t
 438                                     > op( this );
 439
 440             apply_operation( view( images )
 441                            , op
 442                            );
 443         }
 444     }
 445 };
 446
 447 #if BOOST_WORKAROUND(BOOST_MSVC, >= 1400)
 448 #pragma warning(pop)
 449 #endif
 450
 451 } // gil
 452 } // boost
 453
 454 #endif