src/common/imagbmp.cpp

/////////////////////////////////////////////////////////////////////////////
// Name:        imagbmp.cpp
// Purpose:     wxImage BMP handler
// Author:      Robert Roebling
// RCS-ID:      $Id$
// Copyright:   (c) Robert Roebling
// Licence:     wxWindows licence
/////////////////////////////////////////////////////////////////////////////

#ifdef __GNUG__
#pragma implementation "imagbmp.h"
#endif

// For compilers that support precompilation, includes "wx.h".
#include "wx/wxprec.h"

#ifdef __BORLANDC__
#pragma hdrstop
#endif

#include "wx/defs.h"

#if wxUSE_IMAGE

#include "wx/imagbmp.h"
#include "wx/bitmap.h"
#include "wx/debug.h"
#include "wx/log.h"
#include "wx/app.h"
#include "wx/filefn.h"
#include "wx/wfstream.h"
#include "wx/intl.h"
#include "wx/module.h"
#include "wx/quantize.h"

// For memcpy
#include <string.h>

#ifdef __SALFORDC__
#ifdef FAR
#undef FAR
#endif
#endif

#ifdef __WXMSW__
#include <windows.h>
#endif

//-----------------------------------------------------------------------------
// wxBMPHandler
//-----------------------------------------------------------------------------

IMPLEMENT_DYNAMIC_CLASS(wxBMPHandler,wxImageHandler)


#if wxUSE_STREAMS


bool wxBMPHandler::SaveFile(wxImage *image,
                            wxOutputStream& stream,
                            bool verbose)
{
    wxCHECK_MSG( image, FALSE, _T("invalid pointer in wxBMPHandler::SaveFile") );

    if (!image->Ok())
    {
        if (verbose) wxLogError(_("BMP: Couldn't save invalid image."));
        return FALSE;
    }

    // get the format of the BMP file to save, else use 24bpp
    unsigned format = wxBMP_24BPP;
    if (image->HasOption(wxBMP_FORMAT))
        format = image->GetOptionInt(wxBMP_FORMAT);

    unsigned bpp;     // # of bits per pixel
    int palette_size; // # of color map entries, ie. 2^bpp colors

    // set the bpp and appropriate palette_size, and do additional checks
    if ((format == wxBMP_1BPP) || (format == wxBMP_1BPP_BW))
    {
        bpp = 1;
        palette_size = 2;
    }
    else if (format == wxBMP_4BPP)
    {
        bpp = 4;
        palette_size = 16;
    }
    else if ((format == wxBMP_8BPP) || (format == wxBMP_8BPP_GREY) ||
             (format == wxBMP_8BPP_RED) || (format == wxBMP_8BPP_PALETTE))
    {
        // need to set a wxPalette to use this, HOW TO CHECK IF VALID, SIZE?
        if ((format == wxBMP_8BPP_PALETTE)
#if wxUSE_PALETTE
                && !image->HasPalette()
#endif // wxUSE_PALETTE
            )
        {
            if (verbose)
                wxLogError(_("BMP: wImage doesn't have own wxPalette."));
            return FALSE;
        }
        bpp = 8;
        palette_size = 256;
    }
    else  // you get 24bpp
    {
        format = wxBMP_24BPP;
        bpp = 24;
        palette_size = 0;
    }

    unsigned width = image->GetWidth();
    unsigned row_padding = (4 - int(width*bpp/8.0) % 4) % 4; // # bytes to pad to dword
    unsigned row_width = int(width * bpp/8.0) + row_padding; // # of bytes per row

    struct
    {
        // BitmapHeader:
        wxUint16  magic;          // format magic, always 'BM'
        wxUint32  filesize;       // total file size, inc. headers
        wxUint32  reserved;       // for future use
        wxUint32  data_offset;    // image data offset in the file

        // BitmapInfoHeader:
        wxUint32  bih_size;       // 2nd part's size
        wxUint32  width, height;  // bitmap's dimensions
        wxUint16  planes;         // num of planes
        wxUint16  bpp;            // bits per pixel
        wxUint32  compression;    // compression method
        wxUint32  size_of_bmp;    // size of the bitmap
        wxUint32  h_res, v_res;   // image resolution in dpi
        wxUint32  num_clrs;       // number of colors used
        wxUint32  num_signif_clrs;// number of significant colors
    } hdr;

    wxUint32 hdr_size = 14/*BitmapHeader*/ + 40/*BitmapInfoHeader*/;

    hdr.magic = wxUINT16_SWAP_ON_BE(0x4D42/*'BM'*/);
    hdr.filesize = wxUINT32_SWAP_ON_BE( hdr_size + palette_size*4 +
                                        row_width * image->GetHeight() );
    hdr.reserved = 0;
    hdr.data_offset = wxUINT32_SWAP_ON_BE(hdr_size + palette_size*4);

    hdr.bih_size = wxUINT32_SWAP_ON_BE(hdr_size - 14);
    hdr.width = wxUINT32_SWAP_ON_BE(image->GetWidth());
    hdr.height = wxUINT32_SWAP_ON_BE(image->GetHeight());
    hdr.planes = wxUINT16_SWAP_ON_BE(1); // always 1 plane
    hdr.bpp = wxUINT16_SWAP_ON_BE(bpp);
    hdr.compression = 0; // RGB uncompressed
    hdr.size_of_bmp = wxUINT32_SWAP_ON_BE(row_width * image->GetHeight());
    hdr.h_res = hdr.v_res = wxUINT32_SWAP_ON_BE(72);  // 72dpi is standard
    hdr.num_clrs = wxUINT32_SWAP_ON_BE(palette_size); // # colors in colormap
    hdr.num_signif_clrs = 0;     // all colors are significant

    if (// VS: looks ugly but compilers tend to do ugly things with structs,
        //     like aligning hdr.filesize's ofset to dword :(
        // VZ: we should add padding then...
        !stream.Write(&hdr.magic, 2) ||
        !stream.Write(&hdr.filesize, 4) ||
        !stream.Write(&hdr.reserved, 4) ||
        !stream.Write(&hdr.data_offset, 4) ||
        !stream.Write(&hdr.bih_size, 4) ||
        !stream.Write(&hdr.width, 4) ||
        !stream.Write(&hdr.height, 4) ||
        !stream.Write(&hdr.planes, 2) ||
        !stream.Write(&hdr.bpp, 2) ||
        !stream.Write(&hdr.compression, 4) ||
        !stream.Write(&hdr.size_of_bmp, 4) ||
        !stream.Write(&hdr.h_res, 4) ||
        !stream.Write(&hdr.v_res, 4) ||
        !stream.Write(&hdr.num_clrs, 4) ||
        !stream.Write(&hdr.num_signif_clrs, 4)
       )
    {
        if (verbose)
            wxLogError(_("BMP: Couldn't write the file header."));
        return FALSE;
    }

    wxPalette *palette = NULL; // entries for quantized images
    wxUint8 *rgbquad = NULL;   // for the RGBQUAD bytes for the colormap
    wxImage *q_image = NULL;   // destination for quantized image

    // if <24bpp use quantization to reduce colors for *some* of the formats
    if ( (format == wxBMP_1BPP) || (format == wxBMP_4BPP) ||
         (format == wxBMP_8BPP) || (format == wxBMP_8BPP_PALETTE))
    {
        // make a new palette and quantize the image
        if (format != wxBMP_8BPP_PALETTE)
        {
            q_image = new wxImage();

            // I get a delete error using Quantize when desired colors > 236
            int quantize = ((palette_size > 236) ? 236 : palette_size);
            // fill the destination too, it gives much nicer 4bpp images
            wxQuantize::Quantize( *image, *q_image, &palette, quantize, 0,
                                  wxQUANTIZE_FILL_DESTINATION_IMAGE );
        }
        else
        {
#if wxUSE_PALETTE
            palette = new wxPalette(image->GetPalette());
#endif // wxUSE_PALETTE
        }

        int i;
        unsigned char r, g, b;
        rgbquad = new wxUint8 [palette_size*4];

        for (i=0; i<palette_size; i++)
        {
#if wxUSE_PALETTE
            if (!palette->GetRGB( i, &r, &g, &b ))
#endif // wxUSE_PALETTE
                r = g = b = 0;

            rgbquad[i*4] = b;
            rgbquad[i*4+1] = g;
            rgbquad[i*4+2] = r;
            rgbquad[i*4+3] = 0;
        }
    }
    // make a 256 entry greyscale colormap or 2 entry black & white
    else if ((format == wxBMP_8BPP_GREY) || (format == wxBMP_8BPP_RED) ||
             (format == wxBMP_1BPP_BW))
    {
        int i;
        rgbquad = new wxUint8 [palette_size*4];

        for (i=0; i<palette_size; i++)
        {
            // if 1BPP_BW then just 0 and 255 then exit
            if (( i > 0) && (format == wxBMP_1BPP_BW)) i = 255;
            rgbquad[i*4] = i;
            rgbquad[i*4+1] = i;
            rgbquad[i*4+2] = i;
            rgbquad[i*4+3] = 0;
        }
    }

    // if the colormap was made, then it needs to be written
    if (rgbquad)
    {
        if (!stream.Write(rgbquad, palette_size*4))
        {
            if (verbose)
                wxLogError(_("BMP: Couldn't write RGB color map."));
            delete [] rgbquad;
#if wxUSE_PALETTE
            delete palette;
#endif // wxUSE_PALETTE
            delete q_image;
            return FALSE;
        }
        delete []rgbquad;
    }

    // pointer to the image data, use quantized if available
    wxUint8 *data = (wxUint8*) image->GetData();
    if (q_image) if (q_image->Ok()) data = (wxUint8*) q_image->GetData();

    wxUint8 *buffer = new wxUint8[row_width];
    memset(buffer, 0, row_width);
    int y; unsigned x;
    long int pixel;

    for (y = image->GetHeight() -1 ; y >= 0; y--)
    {
        if (format == wxBMP_24BPP)  // 3 bytes per pixel red,green,blue
        {
            for (x = 0; x < width; x++)
            {
                pixel = 3*(y*width + x);

                buffer[3*x    ] = data[pixel+2];
                buffer[3*x + 1] = data[pixel+1];
                buffer[3*x + 2] = data[pixel];
            }
        }
        else if ((format == wxBMP_8BPP) ||       // 1 byte per pixel in color
                 (format == wxBMP_8BPP_PALETTE))
        {
            for (x = 0; x < width; x++)
            {
                pixel = 3*(y*width + x);
#if wxUSE_PALETTE
                buffer[x] = palette->GetPixel( data[pixel],
                                               data[pixel+1],
                                               data[pixel+2] );
#else
                // FIXME: what should this be? use some std palette maybe?
                buffer[x] = 0;
#endif // wxUSE_PALETTE
            }
        }
        else if (format == wxBMP_8BPP_GREY) // 1 byte per pix, rgb ave to grey
        {
            for (x = 0; x < width; x++)
            {
                pixel = 3*(y*width + x);
                buffer[x] = (wxUint8)(.299*data[pixel] +
                                      .587*data[pixel+1] +
                                      .114*data[pixel+2]);
            }
        }
        else if (format == wxBMP_8BPP_RED) // 1 byte per pixel, red as greys
        {
            for (x = 0; x < width; x++)
            {
                buffer[x] = (wxUint8)data[3*(y*width + x)];
            }
        }
        else if (format == wxBMP_4BPP) // 4 bpp in color
        {
            for (x = 0; x < width; x+=2)
            {
                pixel = 3*(y*width + x);

                // fill buffer, ignore if > width
#if wxUSE_PALETTE
                buffer[x/2] =
                    ((wxUint8)palette->GetPixel(data[pixel],
                                                data[pixel+1],
                                                data[pixel+2]) << 4) |
                    (((x+1) > width)
                     ? 0
                     : ((wxUint8)palette->GetPixel(data[pixel+3],
                                                   data[pixel+4],
                                                   data[pixel+5]) ));
#else
                // FIXME: what should this be? use some std palette maybe?
                buffer[x/2] = 0;
#endif // wxUSE_PALETTE
            }
        }
        else if (format == wxBMP_1BPP) // 1 bpp in "color"
        {
            for (x = 0; x < width; x+=8)
            {
                pixel = 3*(y*width + x);

#if wxUSE_PALETTE
                buffer[x/8] = ((wxUint8)palette->GetPixel(data[pixel], data[pixel+1], data[pixel+2]) << 7) |
                    (((x+1) > width) ? 0 : ((wxUint8)palette->GetPixel(data[pixel+3], data[pixel+4], data[pixel+5]) << 6)) |
                    (((x+2) > width) ? 0 : ((wxUint8)palette->GetPixel(data[pixel+6], data[pixel+7], data[pixel+8]) << 5)) |
                    (((x+3) > width) ? 0 : ((wxUint8)palette->GetPixel(data[pixel+9], data[pixel+10], data[pixel+11]) << 4)) |
                    (((x+4) > width) ? 0 : ((wxUint8)palette->GetPixel(data[pixel+12], data[pixel+13], data[pixel+14]) << 3)) |
                    (((x+5) > width) ? 0 : ((wxUint8)palette->GetPixel(data[pixel+15], data[pixel+16], data[pixel+17]) << 2)) |
                    (((x+6) > width) ? 0 : ((wxUint8)palette->GetPixel(data[pixel+18], data[pixel+19], data[pixel+20]) << 1)) |
                    (((x+7) > width) ? 0 : ((wxUint8)palette->GetPixel(data[pixel+21], data[pixel+22], data[pixel+23])     ));
#else
                // FIXME: what should this be? use some std palette maybe?
                buffer[x/8] = 0;
#endif // wxUSE_PALETTE
            }
        }
        else if (format == wxBMP_1BPP_BW) // 1 bpp B&W colormap from red color ONLY
        {
            for (x = 0; x < width; x+=8)
            {
                pixel = 3*(y*width + x);

                buffer[x/8] =
                                            (((wxUint8)(data[pixel]   /128.)) << 7) |
                    ( ((x+1) > width) ? 0 : (((wxUint8)(data[pixel+3] /128.)) << 6)) |
                    ( ((x+2) > width) ? 0 : (((wxUint8)(data[pixel+6] /128.)) << 5)) |
                    ( ((x+3) > width) ? 0 : (((wxUint8)(data[pixel+9] /128.)) << 4)) |
                    ( ((x+4) > width) ? 0 : (((wxUint8)(data[pixel+12]/128.)) << 3)) |
                    ( ((x+5) > width) ? 0 : (((wxUint8)(data[pixel+15]/128.)) << 2)) |
                    ( ((x+6) > width) ? 0 : (((wxUint8)(data[pixel+18]/128.)) << 1)) |
                    ( ((x+7) > width) ? 0 : (((wxUint8)(data[pixel+21]/128.))     ));
            }
        }

        if (!stream.Write(buffer, row_width))
        {
            if (verbose)
                wxLogError(_("BMP: Couldn't write data."));
            delete[] buffer;
#if wxUSE_PALETTE
            delete palette;
#endif // wxUSE_PALETTE
            delete q_image;
            return FALSE;
        }
    }
    delete[] buffer;
#if wxUSE_PALETTE
    delete palette;
#endif // wxUSE_PALETTE
    delete q_image;

    return TRUE;
}


#ifndef BI_RGB
#define BI_RGB       0
#define BI_RLE8      1
#define BI_RLE4      2
#endif

#ifndef BI_BITFIELDS
#define BI_BITFIELDS 3
#endif

#define poffset (line * width * 3 + column * 3)

bool wxBMPHandler::LoadFile( wxImage *image, wxInputStream& stream, bool verbose, int WXUNUSED(index) )
{
    int             rshift = 0, gshift = 0, bshift = 0;
    wxUint8         aByte;
    wxUint16        aWord;
    wxInt32         dbuf[4];
	wxInt32         aDword, rmask = 0, gmask = 0, bmask = 0;
    wxInt8          bbuf[4];
    struct _cmap {
        unsigned char r, g, b;
    } *cmap = NULL;

    off_t start_offset = stream.TellI();
    if (start_offset == wxInvalidOffset) start_offset = 0;

    image->Destroy();

    /*
     * Read the BMP header
     */

    stream.Read( bbuf, 2 );
    stream.Read( dbuf, 4 * 4 );

#if 0 // unused
    wxInt32 size = wxINT32_SWAP_ON_BE( dbuf[0] );
#endif
    wxInt32 offset = wxINT32_SWAP_ON_BE( dbuf[2] );

    stream.Read(dbuf, 4 * 2);
    int width = (int)wxINT32_SWAP_ON_BE( dbuf[0] );
    int height = (int)wxINT32_SWAP_ON_BE( dbuf[1] );
    if (width > 32767)
    {
        if (verbose)
            wxLogError( _("BMP: Image width > 32767 pixels for file.") );
        return FALSE;
    }
    if (height > 32767)
    {
        if (verbose)
            wxLogError( _("BMP: Image height > 32767 pixels for file.") );
        return FALSE;
    }

    stream.Read( &aWord, 2 );
/*
    TODO
    int planes = (int)wxUINT16_SWAP_ON_BE( aWord );
*/
    stream.Read( &aWord, 2 );
    int bpp = (int)wxUINT16_SWAP_ON_BE( aWord );
    if (bpp != 1 && bpp != 4 && bpp != 8 && bpp != 16 && bpp != 24 && bpp != 32)
    {
        if (verbose)
            wxLogError( _("BMP: Unknown bitdepth in file.") );
        return FALSE;
    }

    stream.Read( dbuf, 4 * 4 );
    int comp = (int)wxINT32_SWAP_ON_BE( dbuf[0] );
    if (comp != BI_RGB && comp != BI_RLE4 && comp != BI_RLE8 && comp != BI_BITFIELDS)
    {
        if (verbose)
            wxLogError( _("BMP: Unknown encoding in file.") );
        return FALSE;
    }

    stream.Read( dbuf, 4 * 2 );
    int ncolors = (int)wxINT32_SWAP_ON_BE( dbuf[0] );
    if (ncolors == 0)
        ncolors = 1 << bpp;
    /* some more sanity checks */
    if (((comp == BI_RLE4) && (bpp != 4)) ||
        ((comp == BI_RLE8) && (bpp != 8)) ||
        ((comp == BI_BITFIELDS) && (bpp != 16 && bpp != 32)))
    {
        if (verbose)
            wxLogError( _("BMP: Encoding doesn't match bitdepth.") );
        return FALSE;
    }
    if (bpp < 16)
    {
        cmap = (struct _cmap *)malloc(sizeof(struct _cmap) * ncolors);
        if (!cmap)
        {
            if (verbose)
                wxLogError( _("BMP: Couldn't allocate memory.") );
            return FALSE;
        }
    }
    else
        cmap = NULL;

    image->Create( width, height );
    unsigned char *ptr = image->GetData();
    if (!ptr)
    {
        if (verbose)
            wxLogError( _("BMP: Couldn't allocate memory.") );
        if (cmap)
            free(cmap);
        return FALSE;
    }

    /*
     * Reading the palette, if it exists.
     */
    if (bpp < 16 && ncolors != 0)
    {
        unsigned char* r = new unsigned char[ncolors];
        unsigned char* g = new unsigned char[ncolors];
        unsigned char* b = new unsigned char[ncolors];
        for (int j = 0; j < ncolors; j++)
        {
            stream.Read( bbuf, 4 );
            cmap[j].b = bbuf[0];
            cmap[j].g = bbuf[1];
            cmap[j].r = bbuf[2];

            r[j] = cmap[j].r;
            g[j] = cmap[j].g;
            b[j] = cmap[j].b;
        }

#if wxUSE_PALETTE
        // Set the palette for the wxImage
        image->SetPalette(wxPalette(ncolors, r, g, b));
#endif // wxUSE_PALETTE

        delete[] r;
        delete[] g;
        delete[] b;
    }
    else if (bpp == 16 || bpp == 32)
    {
        if (comp == BI_BITFIELDS)
        {
            int bit = 0;
            stream.Read( dbuf, 4 * 3 );
            bmask = wxINT32_SWAP_ON_BE( dbuf[0] );
            gmask = wxINT32_SWAP_ON_BE( dbuf[1] );
            rmask = wxINT32_SWAP_ON_BE( dbuf[2] );
            /* find shift amount.. ugly, but i can't think of a better way */
            for (bit = 0; bit < bpp; bit++)
            {
                if (bmask & (1 << bit))
                    bshift = bit;
                if (gmask & (1 << bit))
                    gshift = bit;
                if (rmask & (1 << bit))
                    rshift = bit;
            }
        }
        else if (bpp == 16)
        {
            rmask = 0x7C00;
            gmask = 0x03E0;
            bmask = 0x001F;
            rshift = 10;
            gshift = 5;
            bshift = 0;
        }
        else if (bpp == 32)
        {
            rmask = 0x00FF0000;
            gmask = 0x0000FF00;
            bmask = 0x000000FF;
            rshift = 16;
            gshift = 8;
            bshift = 0;
        }
    }

    /*
     * Reading the image data
     */
    stream.SeekI( start_offset + offset );
    unsigned char *data = ptr;

    /* set the whole image to the background color */
    if (bpp < 16 && (comp == BI_RLE4 || comp == BI_RLE8))
    {
        for (int i = 0; i < width * height; i++)
        {
            *ptr++ = cmap[0].r;
            *ptr++ = cmap[0].g;
            *ptr++ = cmap[0].b;
        }
        ptr = data;
    }

    int line = 0;
    int column = 0;
    int linesize = ((width * bpp + 31) / 32) * 4;

    /* BMPs are stored upside down */
    for (line = (height - 1); line >= 0; line--)
    {
        int linepos = 0;
        for (column = 0; column < width;)
        {
            if (bpp < 16)
            {
                int index = 0;
                linepos++;
                aByte = stream.GetC();
                if (bpp == 1)
                {
                    int bit = 0;
                    for (bit = 0; bit < 8 && column < width; bit++)
                    {
                        index = ((aByte & (0x80 >> bit)) ? 1 : 0);
                        ptr[poffset] = cmap[index].r;
                        ptr[poffset + 1] = cmap[index].g;
                        ptr[poffset + 2] = cmap[index].b;
                        column++;
                    }
                }
                else if (bpp == 4)
                {
                    if (comp == BI_RLE4)
                    {
                        if (verbose)
                            wxLogError( _("BMP: Cannot deal with 4bit encoded yet.") );
                        image->Destroy();
                        free(cmap);
                        return FALSE;
                    }
                    else
                    {
                        int nibble = 0;
                        for (nibble = 0; nibble < 2 && column < width; nibble++)
                        {
                            index = ((aByte & (0xF0 >> nibble * 4)) >> (!nibble * 4));
                            if (index >= 16)
                                index = 15;
                            ptr[poffset] = cmap[index].r;
                            ptr[poffset + 1] = cmap[index].g;
                            ptr[poffset + 2] = cmap[index].b;
                            column++;
                        }
                    }
                }
                else if (bpp == 8)
                {
                    if (comp == BI_RLE8)
                    {
                        unsigned char first;
                        first = aByte;
                        aByte = stream.GetC();
                        if (first == 0)
                        {
                            if (aByte == 0)
                            {
                                /* column = width; */
                            }
                            else if (aByte == 1)
                            {
                                column = width;
                                line = -1;
                            }
                            else if (aByte == 2)
                            {
                                aByte = stream.GetC();
                                column += aByte;
                                linepos = column * bpp / 8;
                                aByte = stream.GetC();
                                line += aByte;
                            }
                            else
                            {
                                int absolute = aByte;
                                for (int k = 0; k < absolute; k++)
                                {
                                    linepos++;
                                    aByte = stream.GetC();
                                    ptr[poffset    ] = cmap[aByte].r;
                                    ptr[poffset + 1] = cmap[aByte].g;
                                    ptr[poffset + 2] = cmap[aByte].b;
                                    column++;
                                }
                                if (absolute & 0x01)
                                    aByte = stream.GetC();
                            }
                        }
                        else
                        {
                            for (int l = 0; l < first && column < width; l++)
                            {
                                ptr[poffset    ] = cmap[aByte].r;
                                ptr[poffset + 1] = cmap[aByte].g;
                                ptr[poffset + 2] = cmap[aByte].b;
                                column++;
                                linepos++;
                            }
                        }
                    }
                    else
                    {
                        ptr[poffset    ] = cmap[aByte].r;
                        ptr[poffset + 1] = cmap[aByte].g;
                        ptr[poffset + 2] = cmap[aByte].b;
                        column++;
                        // linepos += size;    seems to be wrong, RR
                    }
                }
               }
               else if (bpp == 24)
               {
                   stream.Read( bbuf, 3 );
                   linepos += 3;
                   ptr[poffset    ] = (unsigned char)bbuf[2];
                   ptr[poffset + 1] = (unsigned char)bbuf[1];
                   ptr[poffset + 2] = (unsigned char)bbuf[0];
                   column++;
               }
               else if (bpp == 16)
               {
                   unsigned char temp;
                   stream.Read( &aWord, 2 );
                   aWord = wxUINT16_SWAP_ON_BE( aWord );
                   linepos += 2;
                   temp = (aWord & rmask) >> rshift;
                   ptr[poffset] = temp;
                   temp = (aWord & gmask) >> gshift;
                   ptr[poffset + 1] = temp;
                   temp = (aWord & bmask) >> bshift;
                   ptr[poffset + 2] = temp;
                   column++;
               }
               else
               {
                   unsigned char temp;
                   stream.Read( &aDword, 4 );
                   aDword = wxINT32_SWAP_ON_BE( aDword );
                   linepos += 4;
                   temp = (aDword & rmask) >> rshift;
                   ptr[poffset] = temp;
                   temp = (aDword & gmask) >> gshift;
                   ptr[poffset + 1] = temp;
                   temp = (aDword & bmask) >> bshift;
                   ptr[poffset + 2] = temp;
                   column++;
               }
          }
          while ((linepos < linesize) && (comp != 1) && (comp != 2))
          {
              stream.Read( &aByte, 1 );
              linepos += 1;
              if (stream.LastError() != wxStream_NOERROR)
                  break;
          }
     }
     if (cmap)
       free(cmap);

     image->SetMask( FALSE );

     return TRUE;
}

bool wxBMPHandler::DoCanRead( wxInputStream& stream )
{
    unsigned char hdr[2];

    stream.Read(hdr, 2);
    stream.SeekI(-2, wxFromCurrent);
    return (hdr[0] == 'B' && hdr[1] == 'M');
}

#endif // wxUSE_STREAMS

#endif // wxUSE_IMAGE
Commit	Line	Data
	1	/////////////////////////////////////////////////////////////////////////////
	2	// Name: imagbmp.cpp
	3	// Purpose: wxImage BMP handler
	4	// Author: Robert Roebling
	5	// RCS-ID: $Id$
	6	// Copyright: (c) Robert Roebling
	7	// Licence: wxWindows licence
	8	/////////////////////////////////////////////////////////////////////////////
	9
	10	#ifdef __GNUG__
	11	#pragma implementation "imagbmp.h"
	12	#endif
	13
	14	// For compilers that support precompilation, includes "wx.h".
	15	#include "wx/wxprec.h"
	16
	17	#ifdef __BORLANDC__
	18	#pragma hdrstop
	19	#endif
	20
	21	#include "wx/defs.h"
	22
	23	#if wxUSE_IMAGE
	24
	25	#include "wx/imagbmp.h"
	26	#include "wx/bitmap.h"
	27	#include "wx/debug.h"
	28	#include "wx/log.h"
	29	#include "wx/app.h"
	30	#include "wx/filefn.h"
	31	#include "wx/wfstream.h"
	32	#include "wx/intl.h"
	33	#include "wx/module.h"
	34	#include "wx/quantize.h"
	35
	36	// For memcpy
	37	#include <string.h>
	38
	39	#ifdef __SALFORDC__
	40	#ifdef FAR
	41	#undef FAR
	42	#endif
	43	#endif
	44
	45	#ifdef __WXMSW__
	46	#include <windows.h>
	47	#endif
	48
	49	//-----------------------------------------------------------------------------
	50	// wxBMPHandler
	51	//-----------------------------------------------------------------------------
	52
	53	IMPLEMENT_DYNAMIC_CLASS(wxBMPHandler,wxImageHandler)
	54
	55
	56	#if wxUSE_STREAMS
	57
	58
	59	bool wxBMPHandler::SaveFile(wxImage *image,
	60	wxOutputStream& stream,
	61	bool verbose)
	62	{
	63	wxCHECK_MSG( image, FALSE, _T("invalid pointer in wxBMPHandler::SaveFile") );
	64
	65	if (!image->Ok())
	66	{
	67	if (verbose) wxLogError(_("BMP: Couldn't save invalid image."));
	68	return FALSE;
	69	}
	70
	71	// get the format of the BMP file to save, else use 24bpp
	72	unsigned format = wxBMP_24BPP;
	73	if (image->HasOption(wxBMP_FORMAT))
	74	format = image->GetOptionInt(wxBMP_FORMAT);
	75
	76	unsigned bpp; // # of bits per pixel
	77	int palette_size; // # of color map entries, ie. 2^bpp colors
	78
	79	// set the bpp and appropriate palette_size, and do additional checks
	80	if ((format == wxBMP_1BPP) \|\| (format == wxBMP_1BPP_BW))
	81	{
	82	bpp = 1;
	83	palette_size = 2;
	84	}
	85	else if (format == wxBMP_4BPP)
	86	{
	87	bpp = 4;
	88	palette_size = 16;
	89	}
	90	else if ((format == wxBMP_8BPP) \|\| (format == wxBMP_8BPP_GREY) \|\|
	91	(format == wxBMP_8BPP_RED) \|\| (format == wxBMP_8BPP_PALETTE))
	92	{
	93	// need to set a wxPalette to use this, HOW TO CHECK IF VALID, SIZE?
	94	if ((format == wxBMP_8BPP_PALETTE)
	95	#if wxUSE_PALETTE
	96	&& !image->HasPalette()
	97	#endif // wxUSE_PALETTE
	98	)
	99	{
	100	if (verbose)
	101	wxLogError(_("BMP: wImage doesn't have own wxPalette."));
	102	return FALSE;
	103	}
	104	bpp = 8;
	105	palette_size = 256;
	106	}
	107	else // you get 24bpp
	108	{
	109	format = wxBMP_24BPP;
	110	bpp = 24;
	111	palette_size = 0;
	112	}
	113
	114	unsigned width = image->GetWidth();
	115	unsigned row_padding = (4 - int(width*bpp/8.0) % 4) % 4; // # bytes to pad to dword
	116	unsigned row_width = int(width * bpp/8.0) + row_padding; // # of bytes per row
	117
	118	struct
	119	{
	120	// BitmapHeader:
	121	wxUint16 magic; // format magic, always 'BM'
	122	wxUint32 filesize; // total file size, inc. headers
	123	wxUint32 reserved; // for future use
	124	wxUint32 data_offset; // image data offset in the file
	125
	126	// BitmapInfoHeader:
	127	wxUint32 bih_size; // 2nd part's size
	128	wxUint32 width, height; // bitmap's dimensions
	129	wxUint16 planes; // num of planes
	130	wxUint16 bpp; // bits per pixel
	131	wxUint32 compression; // compression method
	132	wxUint32 size_of_bmp; // size of the bitmap
	133	wxUint32 h_res, v_res; // image resolution in dpi
	134	wxUint32 num_clrs; // number of colors used
	135	wxUint32 num_signif_clrs;// number of significant colors
	136	} hdr;
	137
	138	wxUint32 hdr_size = 14/BitmapHeader/ + 40/BitmapInfoHeader/;
	139
	140	hdr.magic = wxUINT16_SWAP_ON_BE(0x4D42/'BM'/);
	141	hdr.filesize = wxUINT32_SWAP_ON_BE( hdr_size + palette_size*4 +
	142	row_width * image->GetHeight() );
	143	hdr.reserved = 0;
	144	hdr.data_offset = wxUINT32_SWAP_ON_BE(hdr_size + palette_size*4);
	145
	146	hdr.bih_size = wxUINT32_SWAP_ON_BE(hdr_size - 14);
	147	hdr.width = wxUINT32_SWAP_ON_BE(image->GetWidth());
	148	hdr.height = wxUINT32_SWAP_ON_BE(image->GetHeight());
	149	hdr.planes = wxUINT16_SWAP_ON_BE(1); // always 1 plane
	150	hdr.bpp = wxUINT16_SWAP_ON_BE(bpp);
	151	hdr.compression = 0; // RGB uncompressed
	152	hdr.size_of_bmp = wxUINT32_SWAP_ON_BE(row_width * image->GetHeight());
	153	hdr.h_res = hdr.v_res = wxUINT32_SWAP_ON_BE(72); // 72dpi is standard
	154	hdr.num_clrs = wxUINT32_SWAP_ON_BE(palette_size); // # colors in colormap
	155	hdr.num_signif_clrs = 0; // all colors are significant
	156
	157	if (// VS: looks ugly but compilers tend to do ugly things with structs,
	158	// like aligning hdr.filesize's ofset to dword :(
	159	// VZ: we should add padding then...
	160	!stream.Write(&hdr.magic, 2) \|\|
	161	!stream.Write(&hdr.filesize, 4) \|\|
	162	!stream.Write(&hdr.reserved, 4) \|\|
	163	!stream.Write(&hdr.data_offset, 4) \|\|
	164	!stream.Write(&hdr.bih_size, 4) \|\|
	165	!stream.Write(&hdr.width, 4) \|\|
	166	!stream.Write(&hdr.height, 4) \|\|
	167	!stream.Write(&hdr.planes, 2) \|\|
	168	!stream.Write(&hdr.bpp, 2) \|\|
	169	!stream.Write(&hdr.compression, 4) \|\|
	170	!stream.Write(&hdr.size_of_bmp, 4) \|\|
	171	!stream.Write(&hdr.h_res, 4) \|\|
	172	!stream.Write(&hdr.v_res, 4) \|\|
	173	!stream.Write(&hdr.num_clrs, 4) \|\|
	174	!stream.Write(&hdr.num_signif_clrs, 4)
	175	)
	176	{
	177	if (verbose)
	178	wxLogError(_("BMP: Couldn't write the file header."));
	179	return FALSE;
	180	}
	181
	182	wxPalette *palette = NULL; // entries for quantized images
	183	wxUint8 *rgbquad = NULL; // for the RGBQUAD bytes for the colormap
	184	wxImage *q_image = NULL; // destination for quantized image
	185
	186	// if <24bpp use quantization to reduce colors for some of the formats
	187	if ( (format == wxBMP_1BPP) \|\| (format == wxBMP_4BPP) \|\|
	188	(format == wxBMP_8BPP) \|\| (format == wxBMP_8BPP_PALETTE))
	189	{
	190	// make a new palette and quantize the image
	191	if (format != wxBMP_8BPP_PALETTE)
	192	{
	193	q_image = new wxImage();
	194
	195	// I get a delete error using Quantize when desired colors > 236
	196	int quantize = ((palette_size > 236) ? 236 : palette_size);
	197	// fill the destination too, it gives much nicer 4bpp images
	198	wxQuantize::Quantize( image, q_image, &palette, quantize, 0,
	199	wxQUANTIZE_FILL_DESTINATION_IMAGE );
	200	}
	201	else
	202	{
	203	#if wxUSE_PALETTE
	204	palette = new wxPalette(image->GetPalette());
	205	#endif // wxUSE_PALETTE
	206	}
	207
	208	int i;
	209	unsigned char r, g, b;
	210	rgbquad = new wxUint8 [palette_size*4];
	211
	212	for (i=0; i<palette_size; i++)
	213	{
	214	#if wxUSE_PALETTE
	215	if (!palette->GetRGB( i, &r, &g, &b ))
	216	#endif // wxUSE_PALETTE
	217	r = g = b = 0;
	218
	219	rgbquad[i*4] = b;
	220	rgbquad[i*4+1] = g;
	221	rgbquad[i*4+2] = r;
	222	rgbquad[i*4+3] = 0;
	223	}
	224	}
	225	// make a 256 entry greyscale colormap or 2 entry black & white
	226	else if ((format == wxBMP_8BPP_GREY) \|\| (format == wxBMP_8BPP_RED) \|\|
	227	(format == wxBMP_1BPP_BW))
	228	{
	229	int i;
	230	rgbquad = new wxUint8 [palette_size*4];
	231
	232	for (i=0; i<palette_size; i++)
	233	{
	234	// if 1BPP_BW then just 0 and 255 then exit
	235	if (( i > 0) && (format == wxBMP_1BPP_BW)) i = 255;
	236	rgbquad[i*4] = i;
	237	rgbquad[i*4+1] = i;
	238	rgbquad[i*4+2] = i;
	239	rgbquad[i*4+3] = 0;
	240	}
	241	}
	242
	243	// if the colormap was made, then it needs to be written
	244	if (rgbquad)
	245	{
	246	if (!stream.Write(rgbquad, palette_size*4))
	247	{
	248	if (verbose)
	249	wxLogError(_("BMP: Couldn't write RGB color map."));
	250	delete [] rgbquad;
	251	#if wxUSE_PALETTE
	252	delete palette;
	253	#endif // wxUSE_PALETTE
	254	delete q_image;
	255	return FALSE;
	256	}
	257	delete []rgbquad;
	258	}
	259
	260	// pointer to the image data, use quantized if available
	261	wxUint8 data = (wxUint8) image->GetData();
	262	if (q_image) if (q_image->Ok()) data = (wxUint8*) q_image->GetData();
	263
	264	wxUint8 *buffer = new wxUint8[row_width];
	265	memset(buffer, 0, row_width);
	266	int y; unsigned x;
	267	long int pixel;
	268
	269	for (y = image->GetHeight() -1 ; y >= 0; y--)
	270	{
	271	if (format == wxBMP_24BPP) // 3 bytes per pixel red,green,blue
	272	{
	273	for (x = 0; x < width; x++)
	274	{
	275	pixel = 3(ywidth + x);
	276
	277	buffer[3*x ] = data[pixel+2];
	278	buffer[3*x + 1] = data[pixel+1];
	279	buffer[3*x + 2] = data[pixel];
	280	}
	281	}
	282	else if ((format == wxBMP_8BPP) \|\| // 1 byte per pixel in color
	283	(format == wxBMP_8BPP_PALETTE))
	284	{
	285	for (x = 0; x < width; x++)
	286	{
	287	pixel = 3(ywidth + x);
	288	#if wxUSE_PALETTE
	289	buffer[x] = palette->GetPixel( data[pixel],
	290	data[pixel+1],
	291	data[pixel+2] );
	292	#else
	293	// FIXME: what should this be? use some std palette maybe?
	294	buffer[x] = 0;
	295	#endif // wxUSE_PALETTE
	296	}
	297	}
	298	else if (format == wxBMP_8BPP_GREY) // 1 byte per pix, rgb ave to grey
	299	{
	300	for (x = 0; x < width; x++)
	301	{
	302	pixel = 3(ywidth + x);
	303	buffer[x] = (wxUint8)(.299*data[pixel] +
	304	.587*data[pixel+1] +
	305	.114*data[pixel+2]);
	306	}
	307	}
	308	else if (format == wxBMP_8BPP_RED) // 1 byte per pixel, red as greys
	309	{
	310	for (x = 0; x < width; x++)
	311	{
	312	buffer[x] = (wxUint8)data[3(ywidth + x)];
	313	}
	314	}
	315	else if (format == wxBMP_4BPP) // 4 bpp in color
	316	{
	317	for (x = 0; x < width; x+=2)
	318	{
	319	pixel = 3(ywidth + x);
	320
	321	// fill buffer, ignore if > width
	322	#if wxUSE_PALETTE
	323	buffer[x/2] =
	324	((wxUint8)palette->GetPixel(data[pixel],
	325	data[pixel+1],
	326	data[pixel+2]) << 4) \|
	327	(((x+1) > width)
	328	? 0
	329	: ((wxUint8)palette->GetPixel(data[pixel+3],
	330	data[pixel+4],
	331	data[pixel+5]) ));
	332	#else
	333	// FIXME: what should this be? use some std palette maybe?
	334	buffer[x/2] = 0;
	335	#endif // wxUSE_PALETTE
	336	}
	337	}
	338	else if (format == wxBMP_1BPP) // 1 bpp in "color"
	339	{
	340	for (x = 0; x < width; x+=8)
	341	{
	342	pixel = 3(ywidth + x);
	343
	344	#if wxUSE_PALETTE
	345	buffer[x/8] = ((wxUint8)palette->GetPixel(data[pixel], data[pixel+1], data[pixel+2]) << 7) \|
	346	(((x+1) > width) ? 0 : ((wxUint8)palette->GetPixel(data[pixel+3], data[pixel+4], data[pixel+5]) << 6)) \|
	347	(((x+2) > width) ? 0 : ((wxUint8)palette->GetPixel(data[pixel+6], data[pixel+7], data[pixel+8]) << 5)) \|
	348	(((x+3) > width) ? 0 : ((wxUint8)palette->GetPixel(data[pixel+9], data[pixel+10], data[pixel+11]) << 4)) \|
	349	(((x+4) > width) ? 0 : ((wxUint8)palette->GetPixel(data[pixel+12], data[pixel+13], data[pixel+14]) << 3)) \|
	350	(((x+5) > width) ? 0 : ((wxUint8)palette->GetPixel(data[pixel+15], data[pixel+16], data[pixel+17]) << 2)) \|
	351	(((x+6) > width) ? 0 : ((wxUint8)palette->GetPixel(data[pixel+18], data[pixel+19], data[pixel+20]) << 1)) \|
	352	(((x+7) > width) ? 0 : ((wxUint8)palette->GetPixel(data[pixel+21], data[pixel+22], data[pixel+23]) ));
	353	#else
	354	// FIXME: what should this be? use some std palette maybe?
	355	buffer[x/8] = 0;
	356	#endif // wxUSE_PALETTE
	357	}
	358	}
	359	else if (format == wxBMP_1BPP_BW) // 1 bpp B&W colormap from red color ONLY
	360	{
	361	for (x = 0; x < width; x+=8)
	362	{
	363	pixel = 3(ywidth + x);
	364
	365	buffer[x/8] =
	366	(((wxUint8)(data[pixel] /128.)) << 7) \|
	367	( ((x+1) > width) ? 0 : (((wxUint8)(data[pixel+3] /128.)) << 6)) \|
	368	( ((x+2) > width) ? 0 : (((wxUint8)(data[pixel+6] /128.)) << 5)) \|
	369	( ((x+3) > width) ? 0 : (((wxUint8)(data[pixel+9] /128.)) << 4)) \|
	370	( ((x+4) > width) ? 0 : (((wxUint8)(data[pixel+12]/128.)) << 3)) \|
	371	( ((x+5) > width) ? 0 : (((wxUint8)(data[pixel+15]/128.)) << 2)) \|
	372	( ((x+6) > width) ? 0 : (((wxUint8)(data[pixel+18]/128.)) << 1)) \|
	373	( ((x+7) > width) ? 0 : (((wxUint8)(data[pixel+21]/128.)) ));
	374	}
	375	}
	376
	377	if (!stream.Write(buffer, row_width))
	378	{
	379	if (verbose)
	380	wxLogError(_("BMP: Couldn't write data."));
	381	delete[] buffer;
	382	#if wxUSE_PALETTE
	383	delete palette;
	384	#endif // wxUSE_PALETTE
	385	delete q_image;
	386	return FALSE;
	387	}
	388	}
	389	delete[] buffer;
	390	#if wxUSE_PALETTE
	391	delete palette;
	392	#endif // wxUSE_PALETTE
	393	delete q_image;
	394
	395	return TRUE;
	396	}
	397
	398
	399
	400	#ifndef BI_RGB
	401	#define BI_RGB 0
	402	#define BI_RLE8 1
	403	#define BI_RLE4 2
	404	#endif
	405
	406	#ifndef BI_BITFIELDS
	407	#define BI_BITFIELDS 3
	408	#endif
	409
	410	#define poffset (line * width * 3 + column * 3)
	411
	412	bool wxBMPHandler::LoadFile( wxImage *image, wxInputStream& stream, bool verbose, int WXUNUSED(index) )
	413	{
	414	int rshift = 0, gshift = 0, bshift = 0;
	415	wxUint8 aByte;
	416	wxUint16 aWord;
	417	wxInt32 dbuf[4];
	418	wxInt32 aDword, rmask = 0, gmask = 0, bmask = 0;
	419	wxInt8 bbuf[4];
	420	struct _cmap {
	421	unsigned char r, g, b;
	422	} *cmap = NULL;
	423
	424	off_t start_offset = stream.TellI();
	425	if (start_offset == wxInvalidOffset) start_offset = 0;
	426
	427	image->Destroy();
	428
	429	/*
	430	* Read the BMP header
	431	*/
	432
	433	stream.Read( bbuf, 2 );
	434	stream.Read( dbuf, 4 * 4 );
	435
	436	#if 0 // unused
	437	wxInt32 size = wxINT32_SWAP_ON_BE( dbuf[0] );
	438	#endif
	439	wxInt32 offset = wxINT32_SWAP_ON_BE( dbuf[2] );
	440
	441	stream.Read(dbuf, 4 * 2);
	442	int width = (int)wxINT32_SWAP_ON_BE( dbuf[0] );
	443	int height = (int)wxINT32_SWAP_ON_BE( dbuf[1] );
	444	if (width > 32767)
	445	{
	446	if (verbose)
	447	wxLogError( _("BMP: Image width > 32767 pixels for file.") );
	448	return FALSE;
	449	}
	450	if (height > 32767)
	451	{
	452	if (verbose)
	453	wxLogError( _("BMP: Image height > 32767 pixels for file.") );
	454	return FALSE;
	455	}
	456
	457	stream.Read( &aWord, 2 );
	458	/*
	459	TODO
	460	int planes = (int)wxUINT16_SWAP_ON_BE( aWord );
	461	*/
	462	stream.Read( &aWord, 2 );
	463	int bpp = (int)wxUINT16_SWAP_ON_BE( aWord );
	464	if (bpp != 1 && bpp != 4 && bpp != 8 && bpp != 16 && bpp != 24 && bpp != 32)
	465	{
	466	if (verbose)
	467	wxLogError( _("BMP: Unknown bitdepth in file.") );
	468	return FALSE;
	469	}
	470
	471	stream.Read( dbuf, 4 * 4 );
	472	int comp = (int)wxINT32_SWAP_ON_BE( dbuf[0] );
	473	if (comp != BI_RGB && comp != BI_RLE4 && comp != BI_RLE8 && comp != BI_BITFIELDS)
	474	{
	475	if (verbose)
	476	wxLogError( _("BMP: Unknown encoding in file.") );
	477	return FALSE;
	478	}
	479
	480	stream.Read( dbuf, 4 * 2 );
	481	int ncolors = (int)wxINT32_SWAP_ON_BE( dbuf[0] );
	482	if (ncolors == 0)
	483	ncolors = 1 << bpp;
	484	/* some more sanity checks */
	485	if (((comp == BI_RLE4) && (bpp != 4)) \|\|
	486	((comp == BI_RLE8) && (bpp != 8)) \|\|
	487	((comp == BI_BITFIELDS) && (bpp != 16 && bpp != 32)))
	488	{
	489	if (verbose)
	490	wxLogError( _("BMP: Encoding doesn't match bitdepth.") );
	491	return FALSE;
	492	}
	493	if (bpp < 16)
	494	{
	495	cmap = (struct _cmap )malloc(sizeof(struct _cmap) ncolors);
	496	if (!cmap)
	497	{
	498	if (verbose)
	499	wxLogError( _("BMP: Couldn't allocate memory.") );
	500	return FALSE;
	501	}
	502	}
	503	else
	504	cmap = NULL;
	505
	506	image->Create( width, height );
	507	unsigned char *ptr = image->GetData();
	508	if (!ptr)
	509	{
	510	if (verbose)
	511	wxLogError( _("BMP: Couldn't allocate memory.") );
	512	if (cmap)
	513	free(cmap);
	514	return FALSE;
	515	}
	516
	517	/*
	518	* Reading the palette, if it exists.
	519	*/
	520	if (bpp < 16 && ncolors != 0)
	521	{
	522	unsigned char* r = new unsigned char[ncolors];
	523	unsigned char* g = new unsigned char[ncolors];
	524	unsigned char* b = new unsigned char[ncolors];
	525	for (int j = 0; j < ncolors; j++)
	526	{
	527	stream.Read( bbuf, 4 );
	528	cmap[j].b = bbuf[0];
	529	cmap[j].g = bbuf[1];
	530	cmap[j].r = bbuf[2];
	531
	532	r[j] = cmap[j].r;
	533	g[j] = cmap[j].g;
	534	b[j] = cmap[j].b;
	535	}
	536
	537	#if wxUSE_PALETTE
	538	// Set the palette for the wxImage
	539	image->SetPalette(wxPalette(ncolors, r, g, b));
	540	#endif // wxUSE_PALETTE
	541
	542	delete[] r;
	543	delete[] g;
	544	delete[] b;
	545	}
	546	else if (bpp == 16 \|\| bpp == 32)
	547	{
	548	if (comp == BI_BITFIELDS)
	549	{
	550	int bit = 0;
	551	stream.Read( dbuf, 4 * 3 );
	552	bmask = wxINT32_SWAP_ON_BE( dbuf[0] );
	553	gmask = wxINT32_SWAP_ON_BE( dbuf[1] );
	554	rmask = wxINT32_SWAP_ON_BE( dbuf[2] );
	555	/* find shift amount.. ugly, but i can't think of a better way */
	556	for (bit = 0; bit < bpp; bit++)
	557	{
	558	if (bmask & (1 << bit))
	559	bshift = bit;
	560	if (gmask & (1 << bit))
	561	gshift = bit;
	562	if (rmask & (1 << bit))
	563	rshift = bit;
	564	}
	565	}
	566	else if (bpp == 16)
	567	{
	568	rmask = 0x7C00;
	569	gmask = 0x03E0;
	570	bmask = 0x001F;
	571	rshift = 10;
	572	gshift = 5;
	573	bshift = 0;
	574	}
	575	else if (bpp == 32)
	576	{
	577	rmask = 0x00FF0000;
	578	gmask = 0x0000FF00;
	579	bmask = 0x000000FF;
	580	rshift = 16;
	581	gshift = 8;
	582	bshift = 0;
	583	}
	584	}
	585
	586	/*
	587	* Reading the image data
	588	*/
	589	stream.SeekI( start_offset + offset );
	590	unsigned char *data = ptr;
	591
	592	/* set the whole image to the background color */
	593	if (bpp < 16 && (comp == BI_RLE4 \|\| comp == BI_RLE8))
	594	{
	595	for (int i = 0; i < width * height; i++)
	596	{
	597	*ptr++ = cmap[0].r;
	598	*ptr++ = cmap[0].g;
	599	*ptr++ = cmap[0].b;
	600	}
	601	ptr = data;
	602	}
	603
	604	int line = 0;
	605	int column = 0;
	606	int linesize = ((width * bpp + 31) / 32) * 4;
	607
	608	/* BMPs are stored upside down */
	609	for (line = (height - 1); line >= 0; line--)
	610	{
	611	int linepos = 0;
	612	for (column = 0; column < width;)
	613	{
	614	if (bpp < 16)
	615	{
	616	int index = 0;
	617	linepos++;
	618	aByte = stream.GetC();
	619	if (bpp == 1)
	620	{
	621	int bit = 0;
	622	for (bit = 0; bit < 8 && column < width; bit++)
	623	{
	624	index = ((aByte & (0x80 >> bit)) ? 1 : 0);
	625	ptr[poffset] = cmap[index].r;
	626	ptr[poffset + 1] = cmap[index].g;
	627	ptr[poffset + 2] = cmap[index].b;
	628	column++;
	629	}
	630	}
	631	else if (bpp == 4)
	632	{
	633	if (comp == BI_RLE4)
	634	{
	635	if (verbose)
	636	wxLogError( _("BMP: Cannot deal with 4bit encoded yet.") );
	637	image->Destroy();
	638	free(cmap);
	639	return FALSE;
	640	}
	641	else
	642	{
	643	int nibble = 0;
	644	for (nibble = 0; nibble < 2 && column < width; nibble++)
	645	{
	646	index = ((aByte & (0xF0 >> nibble * 4)) >> (!nibble * 4));
	647	if (index >= 16)
	648	index = 15;
	649	ptr[poffset] = cmap[index].r;
	650	ptr[poffset + 1] = cmap[index].g;
	651	ptr[poffset + 2] = cmap[index].b;
	652	column++;
	653	}
	654	}
	655	}
	656	else if (bpp == 8)
	657	{
	658	if (comp == BI_RLE8)
	659	{
	660	unsigned char first;
	661	first = aByte;
	662	aByte = stream.GetC();
	663	if (first == 0)
	664	{
	665	if (aByte == 0)
	666	{
	667	/* column = width; */
	668	}
	669	else if (aByte == 1)
	670	{
	671	column = width;
	672	line = -1;
	673	}
	674	else if (aByte == 2)
	675	{
	676	aByte = stream.GetC();
	677	column += aByte;
	678	linepos = column * bpp / 8;
	679	aByte = stream.GetC();
	680	line += aByte;
	681	}
	682	else
	683	{
	684	int absolute = aByte;
	685	for (int k = 0; k < absolute; k++)
	686	{
	687	linepos++;
	688	aByte = stream.GetC();
	689	ptr[poffset ] = cmap[aByte].r;
	690	ptr[poffset + 1] = cmap[aByte].g;
	691	ptr[poffset + 2] = cmap[aByte].b;
	692	column++;
	693	}
	694	if (absolute & 0x01)
	695	aByte = stream.GetC();
	696	}
	697	}
	698	else
	699	{
	700	for (int l = 0; l < first && column < width; l++)
	701	{
	702	ptr[poffset ] = cmap[aByte].r;
	703	ptr[poffset + 1] = cmap[aByte].g;
	704	ptr[poffset + 2] = cmap[aByte].b;
	705	column++;
	706	linepos++;
	707	}
	708	}
	709	}
	710	else
	711	{
	712	ptr[poffset ] = cmap[aByte].r;
	713	ptr[poffset + 1] = cmap[aByte].g;
	714	ptr[poffset + 2] = cmap[aByte].b;
	715	column++;
	716	// linepos += size; seems to be wrong, RR
	717	}
	718	}
	719	}
	720	else if (bpp == 24)
	721	{
	722	stream.Read( bbuf, 3 );
	723	linepos += 3;
	724	ptr[poffset ] = (unsigned char)bbuf[2];
	725	ptr[poffset + 1] = (unsigned char)bbuf[1];
	726	ptr[poffset + 2] = (unsigned char)bbuf[0];
	727	column++;
	728	}
	729	else if (bpp == 16)
	730	{
	731	unsigned char temp;
	732	stream.Read( &aWord, 2 );
	733	aWord = wxUINT16_SWAP_ON_BE( aWord );
	734	linepos += 2;
	735	temp = (aWord & rmask) >> rshift;
	736	ptr[poffset] = temp;
	737	temp = (aWord & gmask) >> gshift;
	738	ptr[poffset + 1] = temp;
	739	temp = (aWord & bmask) >> bshift;
	740	ptr[poffset + 2] = temp;
	741	column++;
	742	}
	743	else
	744	{
	745	unsigned char temp;
	746	stream.Read( &aDword, 4 );
	747	aDword = wxINT32_SWAP_ON_BE( aDword );
	748	linepos += 4;
	749	temp = (aDword & rmask) >> rshift;
	750	ptr[poffset] = temp;
	751	temp = (aDword & gmask) >> gshift;
	752	ptr[poffset + 1] = temp;
	753	temp = (aDword & bmask) >> bshift;
	754	ptr[poffset + 2] = temp;
	755	column++;
	756	}
	757	}
	758	while ((linepos < linesize) && (comp != 1) && (comp != 2))
	759	{
	760	stream.Read( &aByte, 1 );
	761	linepos += 1;
	762	if (stream.LastError() != wxStream_NOERROR)
	763	break;
	764	}
	765	}
	766	if (cmap)
	767	free(cmap);
	768
	769	image->SetMask( FALSE );
	770
	771	return TRUE;
	772	}
	773
	774	bool wxBMPHandler::DoCanRead( wxInputStream& stream )
	775	{
	776	unsigned char hdr[2];
	777
	778	stream.Read(hdr, 2);
	779	stream.SeekI(-2, wxFromCurrent);
	780	return (hdr[0] == 'B' && hdr[1] == 'M');
	781	}
	782
	783	#endif // wxUSE_STREAMS
	784
	785	#endif // wxUSE_IMAGE