CLAW Library (a C++ Library Absolutely Wonderful) 1.5.5
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claw::graphic::bitmap::reader Class Reference

This class read data from a bitmap file and store it in an image. More...

#include <bitmap.hpp>

Inheritance diagram for claw::graphic::bitmap::reader:
claw::graphic::bitmap::file_structure

List of all members.

Classes

class  pixel1_to_pixel32
 Functor converting a 1bpp buffer to a 32bpp buffer. More...
class  pixel24_to_pixel32
 Functor converting a 24bpp buffer to a 32bpp buffer. More...
class  pixel4_to_pixel32
 Functor converting a 4bpp buffer to a 32bpp buffer. More...
class  pixel8_to_pixel32
 Functor converting a 8bpp buffer to a 32bpp buffer. More...
class  rle_bitmap_decoder
 RLE decoder for bitmap RLE format. More...
class  rle_bitmap_output_buffer
 The output buffer for the RLE decoder. More...

Public Member Functions

 reader (image &img)
 Constructor.
 reader (image &img, std::istream &f)
 Constructor.
void load (std::istream &f)
 Load the image data from a stream.

Private Types

typedef buffered_istream
< std::istream > 		file_input_buffer
 The type of the input buffer associated with the file when decoding RLE files.
typedef rle_bitmap_decoder
< rle_bitmap_output_buffer
< true > > 		rle4_decoder
 RLE decoder for 4 bpp bitmap images.
typedef rle_bitmap_decoder
< rle_bitmap_output_buffer
< false > > 		rle8_decoder
 RLE decoder for 8 bpp bitmap images.

Private Member Functions

void load_palette (const header &h, std::istream &f, color_palette_type &palette) const
 Load the palette of the image.
void load_1bpp (const header &h, std::istream &f)
 Load a monochrome bitmap file.
void load_4bpp (const header &h, std::istream &f)
 Loads a 4 bpp bitmap file.
void load_8bpp (const header &h, std::istream &f)
 Loads a 8 bpp bitmap file.
void load_24bpp (const header &h, std::istream &f)
 Loads a 24 bpp bitmap file.
void load_4bpp_rle (const header &h, std::istream &f, const color_palette_type &palette)
 Loads a 4 bpp RLE encoded bitmap file.
void load_4bpp_rgb (const header &h, std::istream &f, const color_palette_type &palette)
 Loads a 4 bpp RGB encoded bitmap file.
void load_8bpp_rle (const header &h, std::istream &f, const color_palette_type &palette)
 Loads a 8 bpp bitmap file.
void load_8bpp_rgb (const header &h, std::istream &f, const color_palette_type &palette)
 Loads a 8 bpp RGB encoded bitmap file.
template<typename Convert >
void load_rgb_data (std::istream &f, unsigned int buffer_size, const color_palette_type &palette, const Convert &pixel_convert)
 Load uncompressed data from the file.

Private Attributes

image & m_image
 The image in which we store the data we read.

Detailed Description

This class read data from a bitmap file and store it in an image.

Author:
Julien Jorge

Definition at line 134 of file bitmap.hpp.

Member Typedef Documentation

typedef buffered_istream<std::istream> claw::graphic::bitmap::reader::file_input_buffer [private]

The type of the input buffer associated with the file when decoding RLE files.

Definition at line 139 of file bitmap.hpp.

typedef rle_bitmap_decoder< rle_bitmap_output_buffer<true> > claw::graphic::bitmap::reader::rle4_decoder [private]

RLE decoder for 4 bpp bitmap images.

Definition at line 210 of file bitmap.hpp.

typedef rle_bitmap_decoder< rle_bitmap_output_buffer<false> > claw::graphic::bitmap::reader::rle8_decoder [private]

RLE decoder for 8 bpp bitmap images.

Definition at line 214 of file bitmap.hpp.

Constructor & Destructor Documentation

claw::graphic::bitmap::reader::reader ( image &  img)

Constructor.

Parameters:
imgThe image in which the data will be stored.

Definition at line 287 of file bitmap_reader.cpp.

  : m_image( img )
{

} // bitmap::reader::reader()
claw::graphic::bitmap::reader::reader ( image &  img,
std::istream &  f 
)

Constructor.

Parameters:
imgThe image in which the data will be stored.
fThe file from which we read the data.
Postcondition:
img contains the data from f.

Definition at line 300 of file bitmap_reader.cpp.

References load().

  : m_image( img )
{
  load(f);
} // bitmap::reader::reader()

Member Function Documentation

void claw::graphic::bitmap::reader::load ( std::istream &  f)

Load the image data from a stream.

Parameters:
fThe file from which we read the data.
Postcondition:
The image passed to the constructor contains the data from f.

Definition at line 312 of file bitmap_reader.cpp.

References claw::graphic::bitmap::file_structure::header::bpp, CLAW_PRECOND, claw::graphic::bitmap::file_structure::header::height, claw::graphic::bitmap::file_structure::header::id, and claw::graphic::bitmap::file_structure::header::width.

Referenced by reader().

{
  CLAW_PRECOND( !!f );
  std::istream::pos_type init_pos = f.tellg();

  try
    {
      header h;

      f.read( reinterpret_cast<char*>(&h), sizeof(header) );

      if ( (h.id[0] == 'B') && (h.id[1] == 'M')
           && (f.rdstate() == std::ios_base::goodbit) )
        {
          m_image.set_size(h.width, h.height);
      
          switch(h.bpp)
            {
            case 1 : load_1bpp(h, f); break;
            case 4 : load_4bpp(h, f); break;
            case 8 : load_8bpp(h, f); break;
              //case 16 : load_16bpp(h, f); break;
            case 24 : load_24bpp(h, f); break;
            default : 
              throw claw::bad_format
                ("bitmap::bitmap: unsupported color depth.");
            }
        }
      else
        throw claw::bad_format( "bitmap::bitmap: invalid header." );
    }
  catch(...)
    {
      f.clear();
      f.seekg( init_pos, std::ios_base::beg );
      throw;
    }
} // bitmap::reader::load()
void claw::graphic::bitmap::reader::load_1bpp ( const header &  h,
std::istream &  f 
) [private]

Load a monochrome bitmap file.

Parameters:
hFile's header, must have been read before call.
fBitmap file.
Precondition:
h.bpp == 1

Definition at line 396 of file bitmap_reader.cpp.

References claw::graphic::bitmap::file_structure::header::bpp, and claw::graphic::bitmap::file_structure::header::data_offset.

{
  assert(h.bpp == 1);
  //assert(h.compression == BMP_COMPRESSION_BITFIELDS);

  color_palette_type palette(2);
  unsigned int buffer_size = m_image.width() / (sizeof(char) * 8);
        
  if ( m_image.width() % (sizeof(char) * 8) )
    ++buffer_size;
    
  load_palette(h, f, palette);
  f.seekg(h.data_offset);

  load_rgb_data(f, buffer_size, palette, pixel1_to_pixel32());
} // bitmap::reader::load_1bpp()
void claw::graphic::bitmap::reader::load_24bpp ( const header &  h,
std::istream &  f 
) [private]

Loads a 24 bpp bitmap file.

Parameters:
hFile's header, must have been read before call.
fBitmap file.
Precondition:
(h.bpp == 24)

Definition at line 467 of file bitmap_reader.cpp.

References claw::graphic::bitmap::file_structure::header::bpp, and claw::graphic::bitmap::file_structure::header::data_offset.

{
  assert(h.bpp == 24);

  unsigned int buffer_size = m_image.width() * 3;
  color_palette_type palette(0);
        
  f.seekg(h.data_offset);

  load_rgb_data(f, buffer_size, palette, pixel24_to_pixel32());
} // bitmap::reader::load_24bpp()
void claw::graphic::bitmap::reader::load_4bpp ( const header &  h,
std::istream &  f 
) [private]

Loads a 4 bpp bitmap file.

Parameters:
hFile's header, must have been read before call.
fBitmap file.
Precondition:
(h.bpp == 4)

Definition at line 421 of file bitmap_reader.cpp.

References claw::graphic::bitmap::file_structure::header::bpp, and claw::graphic::bitmap::file_structure::header::compression.

{
  assert(h.bpp == 4);
  assert( (h.compression == BMP_COMPRESSION_RGB)
          || (h.compression == BMP_COMPRESSION_RLE4) );

  color_palette_type palette(16);
  load_palette(h, f, palette);

  if (h.compression == BMP_COMPRESSION_RLE4)
    load_4bpp_rle(h, f, palette);
  else
    load_4bpp_rgb(h, f, palette);
} // bitmap::reader::load_4bpp()
void claw::graphic::bitmap::reader::load_4bpp_rgb ( const header &  h,
std::istream &  f,
const color_palette_type &  palette 
) [private]

Loads a 4 bpp RGB encoded bitmap file.

Parameters:
hFile's header and palette, must have been read before call.
fBitmap file.
paletteThe color palette to use for converting colors.
Precondition:
(h.bpp == 4) && (h.compression = BMP_COMPRESSION_RGB) && (palette.size() == 16)

Definition at line 514 of file bitmap_reader.cpp.

References claw::graphic::bitmap::file_structure::header::bpp, claw::graphic::bitmap::file_structure::header::compression, claw::graphic::bitmap::file_structure::header::data_offset, and claw::graphic::color_palette< Color >::size().

{
  assert(h.bpp == 4);
  assert(h.compression == BMP_COMPRESSION_RGB);
  assert(palette.size() == 16);

  unsigned int buffer_size = m_image.width() / 2 + m_image.width() % 2;
    
  f.seekg(h.data_offset);

  load_rgb_data(f, buffer_size, palette, pixel4_to_pixel32());
} // bitmap::reader::load_4bpp_rgb()
void claw::graphic::bitmap::reader::load_4bpp_rle ( const header &  h,
std::istream &  f,
const color_palette_type &  palette 
) [private]

Loads a 4 bpp RLE encoded bitmap file.

Parameters:
hFile's header and palette, must have been read before call.
fBitmap file.
paletteThe color palette to use for converting colors.
Precondition:
(h.bpp == 4) && (h.compression = BMP_COMPRESSION_RLE4) && (palette.size() == 16)

Definition at line 489 of file bitmap_reader.cpp.

References claw::graphic::bitmap::file_structure::header::bpp, claw::graphic::bitmap::file_structure::header::compression, claw::graphic::bitmap::file_structure::header::data_offset, claw::rle_decoder< Pattern, InputBuffer, OutputBuffer >::decode(), and claw::graphic::color_palette< Color >::size().

{
  assert(h.bpp == 4);
  assert(h.compression == BMP_COMPRESSION_RLE4);
  assert(palette.size() == 16);

  f.seekg(h.data_offset);

  rle4_decoder decoder;
  rle4_decoder::output_buffer_type output_buffer( palette, m_image );
  file_input_buffer input_buffer(f);

  decoder.decode( input_buffer, output_buffer );
} // bitmap::reader::load_4bpp_rle()
void claw::graphic::bitmap::reader::load_8bpp ( const header &  h,
std::istream &  f 
) [private]

Loads a 8 bpp bitmap file.

Parameters:
hFile's header, must have been read before call.
fBitmap file.
Precondition:
(h.bpp == 8)

Definition at line 444 of file bitmap_reader.cpp.

References claw::graphic::bitmap::file_structure::header::bpp, and claw::graphic::bitmap::file_structure::header::compression.

{
  assert(h.bpp == 8);
  assert( (h.compression == BMP_COMPRESSION_RGB)
          || (h.compression == BMP_COMPRESSION_RLE8) );

  color_palette_type palette(256);
  load_palette(h, f, palette);

  if (h.compression == BMP_COMPRESSION_RLE8)
    load_8bpp_rle(h, f, palette);
  else
    load_8bpp_rgb(h, f, palette);
} // bitmap::reader::load_8bpp()
void claw::graphic::bitmap::reader::load_8bpp_rgb ( const header &  h,
std::istream &  f,
const color_palette_type &  palette 
) [private]

Loads a 8 bpp RGB encoded bitmap file.

Parameters:
hFile's header and palette, must have been read before call.
fBitmap file.
paletteThe color palette to use for converting colors.
Precondition:
(h.bpp == 8) && (h.compression = BMP_COMPRESSION_RGB) && (palette.size() == 256)

Definition at line 562 of file bitmap_reader.cpp.

References claw::graphic::bitmap::file_structure::header::bpp, claw::graphic::bitmap::file_structure::header::compression, claw::graphic::bitmap::file_structure::header::data_offset, and claw::graphic::color_palette< Color >::size().

{
  assert(h.bpp == 8);
  assert(h.compression == BMP_COMPRESSION_RGB);
  assert(palette.size() == 256);

  unsigned int buffer_size = m_image.width();
    
  f.seekg(h.data_offset);

  load_rgb_data(f, buffer_size, palette, pixel8_to_pixel32());
} // bitmap::reader::load_8bpp_rgb()
void claw::graphic::bitmap::reader::load_8bpp_rle ( const header &  h,
std::istream &  f,
const color_palette_type &  palette 
) [private]

Loads a 8 bpp bitmap file.

Parameters:
hFile's header and palette, must have been read before call.
fBitmap file.
paletteThe color palette to use for converting colors.
Precondition:
(h.bpp == 8) && (h.compression = BMP_COMPRESSION_RLE8) && (palette.size() == 256)

Definition at line 537 of file bitmap_reader.cpp.

References claw::graphic::bitmap::file_structure::header::bpp, claw::graphic::bitmap::file_structure::header::compression, claw::graphic::bitmap::file_structure::header::data_offset, claw::rle_decoder< Pattern, InputBuffer, OutputBuffer >::decode(), and claw::graphic::color_palette< Color >::size().

{
  assert(h.bpp == 8);
  assert(h.compression == BMP_COMPRESSION_RLE8);
  assert(palette.size() == 256);

  f.seekg(h.data_offset);

  rle8_decoder decoder;
  rle8_decoder::output_buffer_type output_buffer( palette, m_image );
  file_input_buffer input_buffer(f);

  decoder.decode( input_buffer, output_buffer );
} // bitmap::reader::load_8bpp_rle()
void claw::graphic::bitmap::reader::load_palette ( const header &  h,
std::istream &  f,
color_palette_type &  palette 
) const [private]

Load the palette of the image.

Parameters:
hFile's header, must have been read before call.
fBitmap file.
paletteThe loaded palette.
Precondition:
h.bpp <= 8

Definition at line 360 of file bitmap_reader.cpp.

References claw::graphic::bitmap::file_structure::header::bpp, and claw::graphic::color_palette< Color >::size().

{
  assert(h.bpp <= 8);

  switch(h.bpp)
    {
    case 1 : assert( palette.size() == 2 ); break;
    case 4 : assert( palette.size() == 16 ); break;
    case 8 : assert( palette.size() == 256 ); break;
    }

  const unsigned int sizeof_color = sizeof(color_palette_type::color_type);
  const unsigned int buffer_size = sizeof_color * palette.size();
  char* buffer = new char[buffer_size];

  f.read(buffer, buffer_size);

  for (unsigned int i=0, j=0; i!=buffer_size; i+=sizeof_color, ++j)
    {
      palette[j].components.alpha = 255;
      palette[j].components.blue  = buffer[i];
      palette[j].components.green = buffer[i+1];
      palette[j].components.red   = buffer[i+2];
    }

  delete[] buffer;
} // bitmap::reader::load_palette()
template<typename Convert >
void claw::graphic::bitmap::reader::load_rgb_data ( std::istream &  f,
unsigned int  buffer_size,
const color_palette_type &  palette,
const Convert &  pixel_convert 
) [private]

Load uncompressed data from the file.

Parameters:
fThe file from which we're loading the bitmap.
buffer_sizeNumber of bytes needed to store one line of pixels.
paletteColor palette.
pixel_convertA method to convert one line of pixels from the file to a line of the current bitmap.
Remarks:
The Convert type method must take this four parameters in this order: # scanline& destination line, # const char* input buffer (contains one line of the bitmap), # const color_palette_type& palette The color palette of the file,

Definition at line 161 of file bitmap_reader.tpp.

{
  unsigned int line;

  // lines are 4-bytes aligned, so adjust buffer's size.
  if (buffer_size % 4 != 0) 
    buffer_size += 4 - buffer_size % 4;

  char* buffer = new char[buffer_size];

  for (line = m_image.height(); (line>0) && !f.eof(); )
    {
      --line;
      f.read(buffer, buffer_size);
      pixel_convert( m_image[line], buffer, palette );
    }

  delete[] buffer;

  if ( f.rdstate() != std::ios_base::goodbit )
    throw claw::bad_format("bitmap::reader::load_data");
} // bitmap::reader::load_data()

Member Data Documentation

image& claw::graphic::bitmap::reader::m_image [private]

The image in which we store the data we read.

Definition at line 287 of file bitmap.hpp.

The documentation for this class was generated from the following files:
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