fixing modal dialog quit after nested message box problem

[wxWidgets.git] / src / common / imagtiff.cpp

diff --git a/src/common/imagtiff.cpp b/src/common/imagtiff.cpp
index 4fb132a42dbef10db0df55d22de323167317e506..2b48f30b6df8ae0b5958b738cb94dfb8d30eda8d 100644 (file)
--- a/src/common/imagtiff.cpp
+++ b/src/common/imagtiff.cpp
@@ -1,5 +1,5 @@
 /////////////////////////////////////////////////////////////////////////////
 /////////////////////////////////////////////////////////////////////////////

-// Name:        imagtiff.cpp
+// Name:        src/common/imagtiff.cpp

 // Purpose:     wxImage TIFF handler
 // Author:      Robert Roebling
 // RCS-ID:      $Id$
 // Purpose:     wxImage TIFF handler
 // Author:      Robert Roebling
 // RCS-ID:      $Id$


@@ -7,36 +7,96 @@
 // Licence:     wxWindows licence
 /////////////////////////////////////////////////////////////////////////////
 
 // Licence:     wxWindows licence
 /////////////////////////////////////////////////////////////////////////////
 

-#ifdef __GNUG__
-#pragma implementation "imagtiff.h"
-#endif
+// ============================================================================
+// declarations
+// ============================================================================
+
+// ----------------------------------------------------------------------------
+// headers
+// ----------------------------------------------------------------------------

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

-#pragma hdrstop
+    #pragma hdrstop

 #endif
 
 #endif
 

-#include "wx/defs.h"
-
-#if wxUSE_LIBTIFF
+#if wxUSE_IMAGE && wxUSE_LIBTIFF

 
 #include "wx/imagtiff.h"
 
 #include "wx/imagtiff.h"

-#include "wx/bitmap.h"
-#include "wx/debug.h"
-#include "wx/log.h"
-#include "wx/app.h"
+
+#ifndef WX_PRECOMP
+    #include "wx/log.h"
+    #include "wx/app.h"
+    #include "wx/intl.h"
+    #include "wx/bitmap.h"
+    #include "wx/module.h"
+    #include "wx/wxcrtvararg.h"
+#endif
+

 extern "C"
 {
 extern "C"
 {

+#ifdef __DMC__
+    #include "tif_config.h"
+#endif

     #include "tiff.h"
     #include "tiffio.h"
     #include "tiff.h"
     #include "tiffio.h"

-    #include "tiffiop.h"

 }
 #include "wx/filefn.h"
 #include "wx/wfstream.h"
 }
 #include "wx/filefn.h"
 #include "wx/wfstream.h"

-#include "wx/intl.h"
-#include "wx/module.h"
+
+#ifndef TIFFLINKAGEMODE
+    #if defined(__WATCOMC__) && defined(__WXMGL__)
+        #define TIFFLINKAGEMODE cdecl
+    #else
+        #define TIFFLINKAGEMODE LINKAGEMODE
+    #endif
+#endif
+
+// ============================================================================
+// implementation
+// ============================================================================
+
+// ----------------------------------------------------------------------------
+// TIFF library error/warning handlers
+// ----------------------------------------------------------------------------
+
+static wxString
+FormatTiffMessage(const char *module, const char *fmt, va_list ap)
+{
+    char buf[512];
+    if ( wxCRT_VsnprintfA(buf, WXSIZEOF(buf), fmt, ap) <= 0 )
+    {
+        // this isn't supposed to happen, but if it does, it's better
+        // than nothing
+        strcpy(buf, "Incorrectly formatted TIFF message");
+    }
+    buf[WXSIZEOF(buf)-1] = 0; // make sure it is always NULL-terminated
+
+    wxString msg(buf);
+    if ( module )
+        msg += wxString::Format(_(" (in module \"%s\")"), module);
+
+    return msg;
+}
+
+extern "C"
+{
+
+static void
+TIFFwxWarningHandler(const char* module, const char *fmt, va_list ap)
+{
+    wxLogWarning("%s", FormatTiffMessage(module, fmt, ap));
+}
+
+static void
+TIFFwxErrorHandler(const char* module, const char *fmt, va_list ap)
+{
+    wxLogError("%s", FormatTiffMessage(module, fmt, ap));
+}
+
+} // extern "C"

 
 //-----------------------------------------------------------------------------
 // wxTIFFHandler
 
 //-----------------------------------------------------------------------------
 // wxTIFFHandler


@@ -44,84 +104,165 @@ extern "C"
 
 IMPLEMENT_DYNAMIC_CLASS(wxTIFFHandler,wxImageHandler)
 
 
 IMPLEMENT_DYNAMIC_CLASS(wxTIFFHandler,wxImageHandler)
 

-static tsize_t
-_tiffReadProc(thandle_t handle, tdata_t buf, tsize_t size)
+wxTIFFHandler::wxTIFFHandler()
+{
+    m_name = wxT("TIFF file");
+    m_extension = wxT("tif");
+    m_altExtensions.Add(wxT("tiff"));
+    m_type = wxBITMAP_TYPE_TIF;
+    m_mime = wxT("image/tiff");
+    TIFFSetWarningHandler((TIFFErrorHandler) TIFFwxWarningHandler);
+    TIFFSetErrorHandler((TIFFErrorHandler) TIFFwxErrorHandler);
+}
+
+#if wxUSE_STREAMS
+
+// helper to translate our, possibly 64 bit, wxFileOffset to TIFF, always 32
+// bit, toff_t
+static toff_t wxFileOffsetToTIFF(wxFileOffset ofs)
+{
+    if ( ofs == wxInvalidOffset )
+        return (toff_t)-1;
+
+    toff_t tofs = wx_truncate_cast(toff_t, ofs);
+    wxCHECK_MSG( (wxFileOffset)tofs == ofs, (toff_t)-1,
+                    _T("TIFF library doesn't support large files") );
+
+    return tofs;
+}
+
+// another helper to convert standard seek mode to our
+static wxSeekMode wxSeekModeFromTIFF(int whence)
+{
+    switch ( whence )
+    {
+        case SEEK_SET:
+            return wxFromStart;
+
+        case SEEK_CUR:
+            return wxFromCurrent;
+
+        case SEEK_END:
+            return wxFromEnd;
+
+        default:
+            return wxFromCurrent;
+    }
+}
+
+extern "C"
+{
+
+tsize_t TIFFLINKAGEMODE
+wxTIFFNullProc(thandle_t WXUNUSED(handle),
+          tdata_t WXUNUSED(buf),
+          tsize_t WXUNUSED(size))
+{
+    return (tsize_t) -1;
+}
+
+tsize_t TIFFLINKAGEMODE
+wxTIFFReadProc(thandle_t handle, tdata_t buf, tsize_t size)

 {
     wxInputStream *stream = (wxInputStream*) handle;
     stream->Read( (void*) buf, (size_t) size );
 {
     wxInputStream *stream = (wxInputStream*) handle;
     stream->Read( (void*) buf, (size_t) size );

-    return stream->LastRead();
+    return wx_truncate_cast(tsize_t, stream->LastRead());

 }
 
 }
 

-static tsize_t
-_tiffWriteProc(thandle_t handle, tdata_t buf, tsize_t size)
+tsize_t TIFFLINKAGEMODE
+wxTIFFWriteProc(thandle_t handle, tdata_t buf, tsize_t size)

 {
     wxOutputStream *stream = (wxOutputStream*) handle;
     stream->Write( (void*) buf, (size_t) size );
 {
     wxOutputStream *stream = (wxOutputStream*) handle;
     stream->Write( (void*) buf, (size_t) size );

-    return stream->LastWrite();
+    return wx_truncate_cast(tsize_t, stream->LastWrite());

 }
 
 }
 

-static toff_t
-_tiffSeekProc(thandle_t handle, toff_t off, int whence)
+toff_t TIFFLINKAGEMODE
+wxTIFFSeekIProc(thandle_t handle, toff_t off, int whence)

 {
     wxInputStream *stream = (wxInputStream*) handle;
 {
     wxInputStream *stream = (wxInputStream*) handle;

-    wxSeekMode mode;
-    switch (whence)
-    {
-        case SEEK_SET: mode = wxFromStart; break;
-        case SEEK_CUR: mode = wxFromCurrent; break;
-        case SEEK_END: mode = wxFromEnd; break;
-        default:       mode = wxFromCurrent; break;
-    }

 
 

-    return (toff_t)stream->SeekI( (off_t)off, mode );
+    return wxFileOffsetToTIFF(stream->SeekI((wxFileOffset)off,
+                                            wxSeekModeFromTIFF(whence)));

 }
 
 }
 

-static int
-_tiffCloseProc(thandle_t WXUNUSED(handle))
+toff_t TIFFLINKAGEMODE
+wxTIFFSeekOProc(thandle_t handle, toff_t off, int whence)

 {
 {

-    return 0;  // ?
+    wxOutputStream *stream = (wxOutputStream*) handle;
+
+    return wxFileOffsetToTIFF(stream->SeekO((wxFileOffset)off,
+                                            wxSeekModeFromTIFF(whence)));

 }
 
 }
 

-static toff_t
-_tiffSizeProc(thandle_t handle)
+int TIFFLINKAGEMODE
+wxTIFFCloseIProc(thandle_t WXUNUSED(handle))

 {
 {

-    wxInputStream *stream = (wxInputStream*) handle;
+    // there is no need to close the input stream
+    return 0;
+}
+
+int TIFFLINKAGEMODE
+wxTIFFCloseOProc(thandle_t handle)
+{
+    wxOutputStream *stream = (wxOutputStream*) handle;
+
+    return stream->Close() ? 0 : -1;
+}
+
+toff_t TIFFLINKAGEMODE
+wxTIFFSizeProc(thandle_t handle)
+{
+    wxStreamBase *stream = (wxStreamBase*) handle;

     return (toff_t) stream->GetSize();
 }
 
     return (toff_t) stream->GetSize();
 }
 

-static int
-_tiffMapProc(thandle_t WXUNUSED(handle),
+int TIFFLINKAGEMODE
+wxTIFFMapProc(thandle_t WXUNUSED(handle),

              tdata_t* WXUNUSED(pbase),
              toff_t* WXUNUSED(psize))
 {
     return 0;
 }
 
              tdata_t* WXUNUSED(pbase),
              toff_t* WXUNUSED(psize))
 {
     return 0;
 }
 

-static void
-_tiffUnmapProc(thandle_t WXUNUSED(handle),
+void TIFFLINKAGEMODE
+wxTIFFUnmapProc(thandle_t WXUNUSED(handle),

                tdata_t WXUNUSED(base),
                toff_t WXUNUSED(size))
 {
 }
 
                tdata_t WXUNUSED(base),
                toff_t WXUNUSED(size))
 {
 }
 

+} // extern "C"
+

 TIFF*
 TIFFwxOpen(wxInputStream &stream, const char* name, const char* mode)
 {
     TIFF* tif = TIFFClientOpen(name, mode,
         (thandle_t) &stream,
 TIFF*
 TIFFwxOpen(wxInputStream &stream, const char* name, const char* mode)
 {
     TIFF* tif = TIFFClientOpen(name, mode,
         (thandle_t) &stream,

-        _tiffReadProc, _tiffWriteProc,
-        _tiffSeekProc, _tiffCloseProc, _tiffSizeProc,
-        _tiffMapProc, _tiffUnmapProc);
-
-    if (tif)
-        tif->tif_fd = (int) &stream;
+        wxTIFFReadProc, wxTIFFNullProc,
+        wxTIFFSeekIProc, wxTIFFCloseIProc, wxTIFFSizeProc,
+        wxTIFFMapProc, wxTIFFUnmapProc);

 
     return tif;
 }
 
 
     return tif;
 }
 

+TIFF*
+TIFFwxOpen(wxOutputStream &stream, const char* name, const char* mode)
+{
+    TIFF* tif = TIFFClientOpen(name, mode,
+        (thandle_t) &stream,
+        wxTIFFNullProc, wxTIFFWriteProc,
+        wxTIFFSeekOProc, wxTIFFCloseOProc, wxTIFFSizeProc,
+        wxTIFFMapProc, wxTIFFUnmapProc);
+
+    return tif;
+}

 
 bool wxTIFFHandler::LoadFile( wxImage *image, wxInputStream& stream, bool verbose, int index )
 {
 
 bool wxTIFFHandler::LoadFile( wxImage *image, wxInputStream& stream, bool verbose, int index )
 {

+    if (index == -1)
+        index = 0;
+

     image->Destroy();
 
     TIFF *tif = TIFFwxOpen( stream, "image", "r" );
     image->Destroy();
 
     TIFF *tif = TIFFwxOpen( stream, "image", "r" );


@@ -131,7 +272,7 @@ bool wxTIFFHandler::LoadFile( wxImage *image, wxInputStream& stream, bool verbos
         if (verbose)
             wxLogError( _("TIFF: Error loading image.") );
 
         if (verbose)
             wxLogError( _("TIFF: Error loading image.") );
 

-        return FALSE;
+        return false;

     }
 
     if (!TIFFSetDirectory( tif, (tdir_t)index ))
     }
 
     if (!TIFFSetDirectory( tif, (tdir_t)index ))


@@ -141,26 +282,46 @@ bool wxTIFFHandler::LoadFile( wxImage *image, wxInputStream& stream, bool verbos
 
         TIFFClose( tif );
 
 
         TIFFClose( tif );
 

-        return FALSE;
+        return false;

     }
 
     uint32 w, h;
     }
 
     uint32 w, h;

-    uint32 npixels;

     uint32 *raster;
 
     TIFFGetField( tif, TIFFTAG_IMAGEWIDTH, &w );
     TIFFGetField( tif, TIFFTAG_IMAGELENGTH, &h );
 
     uint32 *raster;
 
     TIFFGetField( tif, TIFFTAG_IMAGEWIDTH, &w );
     TIFFGetField( tif, TIFFTAG_IMAGELENGTH, &h );
 

-    npixels = w * h;
+    uint16 extraSamples;
+    uint16* samplesInfo;
+    TIFFGetFieldDefaulted(tif, TIFFTAG_EXTRASAMPLES,
+                          &extraSamples, &samplesInfo);
+    const bool hasAlpha = (extraSamples == 1 &&
+                           (samplesInfo[0] == EXTRASAMPLE_ASSOCALPHA ||
+                            samplesInfo[0] == EXTRASAMPLE_UNASSALPHA));
+
+    // guard against integer overflow during multiplication which could result
+    // in allocating a too small buffer and then overflowing it
+    const double bytesNeeded = (double)w * (double)h * sizeof(uint32);
+    if ( bytesNeeded >= wxUINT32_MAX )
+    {
+        if ( verbose )
+            wxLogError( _("TIFF: Image size is abnormally big.") );
+
+        TIFFClose(tif);

 
 

-    raster = (uint32*) _TIFFmalloc( npixels * sizeof(uint32) );
+        return false;
+    }
+
+    raster = (uint32*) _TIFFmalloc( bytesNeeded );

 
     if (!raster)
     {
         if (verbose)
             wxLogError( _("TIFF: Couldn't allocate memory.") );
 
 
     if (!raster)
     {
         if (verbose)
             wxLogError( _("TIFF: Couldn't allocate memory.") );
 

-        return FALSE;
+        TIFFClose( tif );
+
+        return false;

     }
 
     image->Create( (int)w, (int)h );
     }
 
     image->Create( (int)w, (int)h );


@@ -170,10 +331,14 @@ bool wxTIFFHandler::LoadFile( wxImage *image, wxInputStream& stream, bool verbos
             wxLogError( _("TIFF: Couldn't allocate memory.") );
 
         _TIFFfree( raster );
             wxLogError( _("TIFF: Couldn't allocate memory.") );
 
         _TIFFfree( raster );

+        TIFFClose( tif );

 
 

-        return FALSE;
+        return false;

     }
 
     }
 

+    if ( hasAlpha )
+        image->SetAlpha();
+

     if (!TIFFReadRGBAImage( tif, w, h, raster, 0 ))
     {
         if (verbose)
     if (!TIFFReadRGBAImage( tif, w, h, raster, 0 ))
     {
         if (verbose)


@@ -181,55 +346,84 @@ bool wxTIFFHandler::LoadFile( wxImage *image, wxInputStream& stream, bool verbos
 
         _TIFFfree( raster );
         image->Destroy();
 
         _TIFFfree( raster );
         image->Destroy();

+        TIFFClose( tif );

 
 

-        return FALSE;
+        return false;

     }
 
     }
 

-    bool hasmask = FALSE;
-

     unsigned char *ptr = image->GetData();
     ptr += w*3*(h-1);
     unsigned char *ptr = image->GetData();
     ptr += w*3*(h-1);

+
+    unsigned char *alpha = hasAlpha ? image->GetAlpha() : NULL;
+    if ( hasAlpha )
+        alpha += w*(h-1);
+

     uint32 pos = 0;
 
     for (uint32 i = 0; i < h; i++)
     {
         for (uint32 j = 0; j < w; j++)
         {
     uint32 pos = 0;
 
     for (uint32 i = 0; i < h; i++)
     {
         for (uint32 j = 0; j < w; j++)
         {

-            unsigned char alpha = (unsigned char)TIFFGetA(raster[pos]);
-            if (alpha < 127)
-            {
-                hasmask = TRUE;
-                ptr[0] = image->GetMaskRed();
-                ptr++;
-                ptr[0] = image->GetMaskGreen();
-                ptr++;
-                ptr[0] = image->GetMaskBlue();
-                ptr++;
-            }
-            else
-            {
-                ptr[0] = (unsigned char)TIFFGetR(raster[pos]);
-                ptr++;
-                ptr[0] = (unsigned char)TIFFGetG(raster[pos]);
-                ptr++;
-                ptr[0] = (unsigned char)TIFFGetB(raster[pos]);
-                ptr++;
-            }
+            *(ptr++) = (unsigned char)TIFFGetR(raster[pos]);
+            *(ptr++) = (unsigned char)TIFFGetG(raster[pos]);
+            *(ptr++) = (unsigned char)TIFFGetB(raster[pos]);
+            if ( hasAlpha )
+                *(alpha++) = (unsigned char)TIFFGetA(raster[pos]);
+

             pos++;
         }
             pos++;
         }

-        ptr -= 2*w*3; // subtract line we just added plus one line
+
+        // subtract line we just added plus one line:
+        ptr -= 2*w*3;
+        if ( hasAlpha )
+            alpha -= 2*w;
+    }
+
+    // set the image resolution if it's available
+    uint16 tiffRes;
+    if ( TIFFGetField(tif, TIFFTAG_RESOLUTIONUNIT, &tiffRes) )
+    {
+        wxImageResolution res;
+        switch ( tiffRes )
+        {
+            default:
+                wxLogWarning(_("Unknown TIFF resolution unit %d ignored"),
+                             tiffRes);
+                // fall through
+
+            case RESUNIT_NONE:
+                res = wxIMAGE_RESOLUTION_NONE;
+                break;
+
+            case RESUNIT_INCH:
+                res = wxIMAGE_RESOLUTION_INCHES;
+                break;
+
+            case RESUNIT_CENTIMETER:
+                res = wxIMAGE_RESOLUTION_CM;
+                break;
+        }
+
+        if ( res != wxIMAGE_RESOLUTION_NONE )
+        {
+            float xres, yres;
+            if ( TIFFGetField(tif, TIFFTAG_XRESOLUTION, &xres) )
+                image->SetOption(wxIMAGE_OPTION_RESOLUTIONX, wxRound(xres));
+
+            if ( TIFFGetField(tif, TIFFTAG_YRESOLUTION, &yres) )
+                image->SetOption(wxIMAGE_OPTION_RESOLUTIONY, wxRound(yres));
+        }

     }
 
     }
 

+

     _TIFFfree( raster );
 
     TIFFClose( tif );
 
     _TIFFfree( raster );
 
     TIFFClose( tif );
 

-    image->SetMask( hasmask );
-
-    return TRUE;
+    return true;

 }
 
 }
 

-int wxTIFFHandler::GetImageCount( wxInputStream& stream )
+int wxTIFFHandler::DoGetImageCount( wxInputStream& stream )

 {
     TIFF *tif = TIFFwxOpen( stream, "image", "r" );
 
 {
     TIFF *tif = TIFFwxOpen( stream, "image", "r" );
 


@@ -242,32 +436,177 @@ int wxTIFFHandler::GetImageCount( wxInputStream& stream )
     } while (TIFFReadDirectory(tif));
 
     TIFFClose( tif );
     } while (TIFFReadDirectory(tif));
 
     TIFFClose( tif );

+    
+    // NOTE: this function modifies the current stream position but it's ok
+    //       (see wxImageHandler::GetImageCount)

 
     return dircount;
 }
 
 
     return dircount;
 }
 

-bool wxTIFFHandler::SaveFile( wxImage *WXUNUSED(image), wxOutputStream& WXUNUSED(stream), bool WXUNUSED(verbose) )
+bool wxTIFFHandler::SaveFile( wxImage *image, wxOutputStream& stream, bool verbose )

 {
 {

-    return FALSE;
-}
+    TIFF *tif = TIFFwxOpen( stream, "image", "w" );

 
 

-bool wxTIFFHandler::DoCanRead( wxInputStream& stream )
-{
-    unsigned char hdr[2];
+    if (!tif)
+    {
+        if (verbose)
+            wxLogError( _("TIFF: Error saving image.") );

 
 

-    stream.Read(&hdr, 2);
-    stream.SeekI(-2, wxFromCurrent);
+        return false;
+    }

 
 

-    return ((hdr[0] == 0x49 && hdr[1] == 0x49) ||
-            (hdr[0] == 0x4D && hdr[1] == 0x4D));
-}
+    TIFFSetField(tif, TIFFTAG_ORIENTATION, ORIENTATION_TOPLEFT);
+    TIFFSetField(tif, TIFFTAG_IMAGEWIDTH,  (uint32)image->GetWidth());
+    TIFFSetField(tif, TIFFTAG_IMAGELENGTH, (uint32)image->GetHeight());
+    TIFFSetField(tif, TIFFTAG_ORIENTATION, ORIENTATION_TOPLEFT);
+    TIFFSetField(tif, TIFFTAG_PLANARCONFIG, PLANARCONFIG_CONTIG);
+
+    // save the image resolution if we have it
+    int xres, yres;
+    const wxImageResolution res = GetResolutionFromOptions(*image, &xres, &yres);
+    uint16 tiffRes;
+    switch ( res )
+    {
+        default:
+            wxFAIL_MSG( _T("unknown image resolution units") );
+            // fall through

 
 

+        case wxIMAGE_RESOLUTION_NONE:
+            tiffRes = RESUNIT_NONE;
+            break;

 
 

-#endif
-   // wxUSE_LIBTIFF
+        case wxIMAGE_RESOLUTION_INCHES:
+            tiffRes = RESUNIT_INCH;
+            break;
+
+        case wxIMAGE_RESOLUTION_CM:
+            tiffRes = RESUNIT_CENTIMETER;
+            break;
+    }
+
+    if ( tiffRes != RESUNIT_NONE )
+    {
+        TIFFSetField(tif, TIFFTAG_RESOLUTIONUNIT, tiffRes);
+        TIFFSetField(tif, TIFFTAG_XRESOLUTION, (float)xres);
+        TIFFSetField(tif, TIFFTAG_YRESOLUTION, (float)yres);
+    }

 
 
 
 

+    int spp = image->GetOptionInt(wxIMAGE_OPTION_SAMPLESPERPIXEL);
+    if ( !spp )
+        spp = 3;

 
 

+    int bpp = image->GetOptionInt(wxIMAGE_OPTION_BITSPERSAMPLE);
+    if ( !bpp )
+        bpp = 8;

 
 

+    int compression = image->GetOptionInt(wxIMAGE_OPTION_COMPRESSION);
+    if ( !compression )
+    {
+        // we can't use COMPRESSION_LZW because current version of libtiff
+        // doesn't implement it ("no longer implemented due to Unisys patent
+        // enforcement") and other compression methods are lossy so we
+        // shouldn't use them by default -- and the only remaining one is none
+        compression = COMPRESSION_NONE;
+    }
+
+    TIFFSetField(tif, TIFFTAG_SAMPLESPERPIXEL, spp);
+    TIFFSetField(tif, TIFFTAG_BITSPERSAMPLE, bpp);
+    TIFFSetField(tif, TIFFTAG_PHOTOMETRIC, spp*bpp == 1 ? PHOTOMETRIC_MINISBLACK
+                                                        : PHOTOMETRIC_RGB);
+    TIFFSetField(tif, TIFFTAG_COMPRESSION, compression);
+
+    // scanlinesize if determined by spp and bpp
+    tsize_t linebytes = (tsize_t)image->GetWidth() * spp * bpp / 8;
+
+    if ( (image->GetWidth() % 8 > 0) && (spp * bpp < 8) )
+        linebytes+=1;
+
+    unsigned char *buf;
+
+    if (TIFFScanlineSize(tif) > linebytes || (spp * bpp < 24))
+    {
+        buf = (unsigned char *)_TIFFmalloc(TIFFScanlineSize(tif));
+        if (!buf)
+        {
+            if (verbose)
+                wxLogError( _("TIFF: Couldn't allocate memory.") );
+
+            TIFFClose( tif );
+
+            return false;
+        }
+    }
+    else
+    {
+        buf = NULL;
+    }
+
+    TIFFSetField(tif, TIFFTAG_ROWSPERSTRIP,TIFFDefaultStripSize(tif, (uint32) -1));
+
+    unsigned char *ptr = image->GetData();
+    for ( int row = 0; row < image->GetHeight(); row++ )
+    {
+        if ( buf )
+        {
+            if ( spp * bpp > 1 )
+            {
+                // color image
+                memcpy(buf, ptr, image->GetWidth());
+            }
+            else // black and white image
+            {
+                for ( int column = 0; column < linebytes; column++ )
+                {
+                    uint8 reverse = 0;
+                    for ( int bp = 0; bp < 8; bp++ )
+                    {
+                        if ( ptr[column*24 + bp*3] > 0 )
+                        {
+                            // check only red as this is sufficient
+                            reverse = (uint8)(reverse | 128 >> bp);
+                        }
+                    }
+
+                    buf[column] = reverse;
+                }
+            }
+        }
+
+        if ( TIFFWriteScanline(tif, buf ? buf : ptr, (uint32)row, 0) < 0 )
+        {
+            if (verbose)
+                wxLogError( _("TIFF: Error writing image.") );
+
+            TIFFClose( tif );
+            if (buf)
+                _TIFFfree(buf);
+
+            return false;
+        }
+
+        ptr += image->GetWidth()*3;
+    }
+
+    (void) TIFFClose(tif);
+
+    if (buf)
+        _TIFFfree(buf);
+
+    return true;
+}
+
+bool wxTIFFHandler::DoCanRead( wxInputStream& stream )
+{
+    unsigned char hdr[2];
+
+    if ( !stream.Read(&hdr[0], WXSIZEOF(hdr)) )     // it's ok to modify the stream position here
+        return false;
+
+    return (hdr[0] == 'I' && hdr[1] == 'I') ||
+           (hdr[0] == 'M' && hdr[1] == 'M');
+}

 
 

+#endif  // wxUSE_STREAMS

 
 

+#endif  // wxUSE_LIBTIFF