]> git.saurik.com Git - wxWidgets.git/blobdiff - src/common/imagbmp.cpp
Return NULL from wxWindow::GetCapture() when the capture is being lost.
[wxWidgets.git] / src / common / imagbmp.cpp
index 1ba36f910c643e169b8a71280eae52f995889100..c3fcfb275e3719c05c64e2e3ed28de5bd4416ed4 100644 (file)
@@ -1,50 +1,52 @@
 /////////////////////////////////////////////////////////////////////////////
-// Name:        imagbmp.cpp
+// Name:        src/common/imagbmp.cpp
 // Purpose:     wxImage BMP,ICO and CUR handlers
 // Author:      Robert Roebling, Chris Elliott
-// RCS-ID:      $Id$
 // Copyright:   (c) Robert Roebling, Chris Elliott
 // 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
+    #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"
+
+#ifndef WX_PRECOMP
+    #ifdef __WXMSW__
+        #include "wx/msw/wrapwin.h"
+    #endif
+    #include "wx/log.h"
+    #include "wx/app.h"
+    #include "wx/bitmap.h"
+    #include "wx/palette.h"
+    #include "wx/intl.h"
+    #include "wx/math.h"
+#endif
+
 #include "wx/filefn.h"
 #include "wx/wfstream.h"
-#include "wx/intl.h"
-#include "wx/module.h"
 #include "wx/quantize.h"
+#include "wx/scopeguard.h"
+#include "wx/anidecod.h"
 
 // For memcpy
 #include <string.h>
 
-#ifdef __SALFORDC__
-#ifdef FAR
-#undef FAR
-#endif
-#endif
+// ----------------------------------------------------------------------------
+// private functions
+// ----------------------------------------------------------------------------
 
-#ifdef __WXMSW__
-#include <windows.h>
-#endif
+#if wxUSE_ICO_CUR
+
+static bool CanReadICOOrCUR(wxInputStream *stream, wxUint16 resourceType);
+
+#endif // wxUSE_ICO_CUR
 
 //-----------------------------------------------------------------------------
 // wxBMPHandler
@@ -55,8 +57,14 @@ IMPLEMENT_DYNAMIC_CLASS(wxBMPHandler,wxImageHandler)
 #if wxUSE_STREAMS
 
 #ifndef BI_RGB
-#define BI_RGB       0
+    #define BI_RGB       0
+#endif
+
+#ifndef BI_RLE8
 #define BI_RLE8      1
+#endif
+
+#ifndef BI_RLE4
 #define BI_RLE4      2
 #endif
 
@@ -70,7 +78,7 @@ bool wxBMPHandler::SaveFile(wxImage *image,
                             wxOutputStream& stream,
                             bool verbose)
 {
-    return SaveDib(image, stream, verbose, TRUE/*IsBmp*/, FALSE/*IsMask*/);
+    return SaveDib(image, stream, verbose, true/*IsBmp*/, false/*IsMask*/);
 }
 
 bool wxBMPHandler::SaveDib(wxImage *image,
@@ -80,13 +88,15 @@ bool wxBMPHandler::SaveDib(wxImage *image,
                            bool IsMask)
 
 {
-    wxCHECK_MSG( image, FALSE, _T("invalid pointer in wxBMPHandler::SaveFile") );
+    wxCHECK_MSG( image, false, wxT("invalid pointer in wxBMPHandler::SaveFile") );
 
-    if ( !image->Ok() )
+    if ( !image->IsOk() )
     {
         if ( verbose )
+        {
             wxLogError(_("BMP: Couldn't save invalid image."));
-        return FALSE;
+        }
+        return false;
     }
 
     // get the format of the BMP file to save, else use 24bpp
@@ -119,8 +129,10 @@ bool wxBMPHandler::SaveDib(wxImage *image,
             )
         {
             if ( verbose )
+            {
                 wxLogError(_("BMP: wxImage doesn't have own wxPalette."));
-            return FALSE;
+            }
+            return false;
         }
         bpp = 8;
         palette_size = 256;
@@ -133,8 +145,8 @@ bool wxBMPHandler::SaveDib(wxImage *image,
     }
 
     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
+    unsigned row_padding = (4 - ((width * bpp + 7) / 8) % 4) % 4; // # bytes to pad to dword
+    unsigned row_width = (width * bpp + 7) / 8 + row_padding; // # of bytes per row
 
     struct
     {
@@ -151,7 +163,7 @@ bool wxBMPHandler::SaveDib(wxImage *image,
         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  h_res, v_res;   // image resolution in pixels-per-meter
         wxUint32  num_clrs;       // number of colors used
         wxUint32  num_signif_clrs;// number of significant colors
     } hdr;
@@ -178,7 +190,36 @@ bool wxBMPHandler::SaveDib(wxImage *image,
     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
+
+    // get the resolution from the image options  or fall back to 72dpi standard
+    // for the BMP format if not specified
+    int hres, vres;
+    switch ( GetResolutionFromOptions(*image, &hres, &vres) )
+    {
+        default:
+            wxFAIL_MSG( wxT("unexpected image resolution units") );
+            // fall through
+
+        case wxIMAGE_RESOLUTION_NONE:
+            hres =
+            vres = 72;
+            // fall through to convert it to correct units
+
+        case wxIMAGE_RESOLUTION_INCHES:
+            // convert resolution in inches to resolution in centimeters
+            hres = (int)(10*mm2inches*hres);
+            vres = (int)(10*mm2inches*vres);
+            // fall through to convert it to resolution in meters
+
+        case wxIMAGE_RESOLUTION_CM:
+            // convert resolution in centimeters to resolution in meters
+            hres *= 100;
+            vres *= 100;
+            break;
+    }
+
+    hdr.h_res = wxUINT32_SWAP_ON_BE(hres);
+    hdr.v_res = wxUINT32_SWAP_ON_BE(vres);
     hdr.num_clrs = wxUINT32_SWAP_ON_BE(palette_size); // # colors in colormap
     hdr.num_signif_clrs = 0;     // all colors are significant
 
@@ -187,36 +228,40 @@ bool wxBMPHandler::SaveDib(wxImage *image,
         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.WriteAll(&hdr.magic, 2) ||
+            !stream.WriteAll(&hdr.filesize, 4) ||
+            !stream.WriteAll(&hdr.reserved, 4) ||
+            !stream.WriteAll(&hdr.data_offset, 4)
            )
         {
             if (verbose)
+            {
                 wxLogError(_("BMP: Couldn't write the file (Bitmap) header."));
-            return FALSE;
+                }
+            return false;
         }
     }
     if ( !IsMask )
     {
         if (
-            !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)
+            !stream.WriteAll(&hdr.bih_size, 4) ||
+            !stream.WriteAll(&hdr.width, 4) ||
+            !stream.WriteAll(&hdr.height, 4) ||
+            !stream.WriteAll(&hdr.planes, 2) ||
+            !stream.WriteAll(&hdr.bpp, 2) ||
+            !stream.WriteAll(&hdr.compression, 4) ||
+            !stream.WriteAll(&hdr.size_of_bmp, 4) ||
+            !stream.WriteAll(&hdr.h_res, 4) ||
+            !stream.WriteAll(&hdr.v_res, 4) ||
+            !stream.WriteAll(&hdr.num_clrs, 4) ||
+            !stream.WriteAll(&hdr.num_signif_clrs, 4)
            )
         {
             if (verbose)
+            {
                 wxLogError(_("BMP: Couldn't write the file (BitmapInfo) header."));
-            return FALSE;
+            }
+            return false;
         }
     }
 
@@ -267,16 +312,16 @@ bool wxBMPHandler::SaveDib(wxImage *image,
     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++)
+        for ( int 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;
+            // if 1BPP_BW then the value should be either 0 or 255
+            wxUint8 c = (wxUint8)((i > 0) && (format == wxBMP_1BPP_BW) ? 255 : i);
+
+            rgbquad[i*4] =
+            rgbquad[i*4+1] =
+            rgbquad[i*4+2] = c;
             rgbquad[i*4+3] = 0;
         }
     }
@@ -286,16 +331,18 @@ bool wxBMPHandler::SaveDib(wxImage *image,
     {
         if ( !IsMask )
         {
-            if ( !stream.Write(rgbquad, palette_size*4) )
+            if ( !stream.WriteAll(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;
+                return false;
             }
             }
         delete []rgbquad;
@@ -303,7 +350,7 @@ bool wxBMPHandler::SaveDib(wxImage *image,
 
     // 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();
+    if (q_image) if (q_image->IsOk()) data = (wxUint8*) q_image->GetData();
 
     wxUint8 *buffer = new wxUint8[row_width];
     memset(buffer, 0, row_width);
@@ -330,9 +377,9 @@ bool wxBMPHandler::SaveDib(wxImage *image,
             {
                 pixel = 3*(y*width + x);
 #if wxUSE_PALETTE
-                buffer[x] = palette->GetPixel( data[pixel],
-                                               data[pixel+1],
-                                               data[pixel+2] );
+                buffer[x] = (wxUint8)palette->GetPixel( data[pixel],
+                                                        data[pixel+1],
+                                                        data[pixel+2] );
 #else
                 // FIXME: what should this be? use some std palette maybe?
                 buffer[x] = 0;
@@ -364,7 +411,7 @@ bool wxBMPHandler::SaveDib(wxImage *image,
 
                 // fill buffer, ignore if > width
 #if wxUSE_PALETTE
-                buffer[x/2] =
+                buffer[x/2] = (wxUint8)(
                     ((wxUint8)palette->GetPixel(data[pixel],
                                                 data[pixel+1],
                                                 data[pixel+2]) << 4) |
@@ -372,7 +419,7 @@ bool wxBMPHandler::SaveDib(wxImage *image,
                      ? 0
                      : ((wxUint8)palette->GetPixel(data[pixel+3],
                                                    data[pixel+4],
-                                                   data[pixel+5]) ));
+                                                   data[pixel+5]) ))    );
 #else
                 // FIXME: what should this be? use some std palette maybe?
                 buffer[x/2] = 0;
@@ -386,14 +433,15 @@ bool wxBMPHandler::SaveDib(wxImage *image,
                 pixel = 3*(y*width + x);
 
 #if wxUSE_PALETTE
-                buffer[x/8] = ((wxUint8)palette->GetPixel(data[pixel], data[pixel+1], data[pixel+2]) << 7) |
+                buffer[x/8] = (wxUint8)(
+                                           ((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])     ));
+                    (((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;
@@ -406,7 +454,7 @@ bool wxBMPHandler::SaveDib(wxImage *image,
             {
                 pixel = 3*(y*width + x);
 
-                buffer[x/8] =
+                buffer[x/8] = (wxUint8)(
                                           (((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)) |
@@ -414,20 +462,22 @@ bool wxBMPHandler::SaveDib(wxImage *image,
                    (((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.))     ));
+                   (((x+7) > width) ? 0 : (((wxUint8)(data[pixel+21]/128.))     ))    );
             }
         }
 
-        if ( !stream.Write(buffer, row_width) )
+        if ( !stream.WriteAll(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;
+            return false;
         }
     }
     delete[] buffer;
@@ -436,22 +486,24 @@ bool wxBMPHandler::SaveDib(wxImage *image,
 #endif // wxUSE_PALETTE
     delete q_image;
 
-    return TRUE;
+    return true;
 }
 
 
-typedef struct
+struct BMPPalette
 {
+    static void Free(BMPPalette* pal) { delete [] pal; }
+
     unsigned char r, g, b;
-}  _cmap;
+};
 
 bool wxBMPHandler::DoLoadDib(wxImage * image, int width, int height,
                              int bpp, int ncolors, int comp,
-                             off_t bmpOffset, wxInputStream& stream,
+                             wxFileOffset bmpOffset, wxInputStream& stream,
                              bool verbose, bool IsBmp, bool hasPalette)
 {
-    wxInt32         aDword, rmask = 0, gmask = 0, bmask = 0;
-    int             rshift = 0, gshift = 0, bshift = 0;
+    wxInt32         aDword, rmask = 0, gmask = 0, bmask = 0, amask = 0;
+    int             rshift = 0, gshift = 0, bshift = 0, ashift = 0;
     int             rbits = 0, gbits = 0, bbits = 0;
     wxInt32         dbuf[4];
     wxInt8          bbuf[4];
@@ -459,20 +511,34 @@ bool wxBMPHandler::DoLoadDib(wxImage * image, int width, int height,
     wxUint16        aWord;
 
     // allocate space for palette if needed:
-    _cmap *cmap = NULL;
+    BMPPalette *cmap;
 
     if ( bpp < 16 )
     {
-        cmap = new _cmap[ncolors];
+        cmap = new BMPPalette[ncolors];
         if ( !cmap )
         {
             if (verbose)
+            {
                 wxLogError(_("BMP: Couldn't allocate memory."));
-            return FALSE;
+            }
+            return false;
         }
     }
-    else
+    else // no palette
+    {
         cmap = NULL;
+    }
+
+    wxON_BLOCK_EXIT1(&BMPPalette::Free, cmap);
+
+    bool isUpsideDown = true;
+
+    if (height < 0)
+    {
+        isUpsideDown = false;
+        height = -height;
+    }
 
     // destroy existing here instead of:
     image->Destroy();
@@ -483,10 +549,30 @@ bool wxBMPHandler::DoLoadDib(wxImage * image, int width, int height,
     if ( !ptr )
     {
         if ( verbose )
+        {
             wxLogError( _("BMP: Couldn't allocate memory.") );
-        if ( cmap )
-            delete[] cmap;
-        return FALSE;
+        }
+        return false;
+    }
+
+    unsigned char *alpha;
+    if ( bpp == 32 )
+    {
+        // tell the image to allocate an alpha buffer
+        image->SetAlpha();
+        alpha = image->GetAlpha();
+        if ( !alpha )
+        {
+            if ( verbose )
+            {
+                wxLogError(_("BMP: Couldn't allocate memory."));
+            }
+            return false;
+        }
+    }
+    else // no alpha
+    {
+        alpha = NULL;
     }
 
     // Reading the palette, if it exists:
@@ -499,7 +585,9 @@ bool wxBMPHandler::DoLoadDib(wxImage * image, int width, int height,
         {
             if (hasPalette)
             {
-                stream.Read(bbuf, 4);
+                if ( !stream.ReadAll(bbuf, 4) )
+                    return false;
+
                 cmap[j].b = bbuf[0];
                 cmap[j].g = bbuf[1];
                 cmap[j].r = bbuf[2];
@@ -511,9 +599,9 @@ bool wxBMPHandler::DoLoadDib(wxImage * image, int width, int height,
             else
             {
                 //used in reading .ico file mask
-                r[j] = cmap[j].r = j * 255;
-                g[j] = cmap[j].g = j * 255;
-                b[j] = cmap[j].b = j * 255;
+                r[j] = cmap[j].r =
+                g[j] = cmap[j].g =
+                b[j] = cmap[j].b = ( j ? 255 : 0 );
             }
         }
 
@@ -530,8 +618,10 @@ bool wxBMPHandler::DoLoadDib(wxImage * image, int width, int height,
     {
         if ( comp == BI_BITFIELDS )
         {
-            int bit = 0;
-            stream.Read(dbuf, 4 * 3);
+            int bit;
+            if ( !stream.ReadAll(dbuf, 4 * 3) )
+                return false;
+
             rmask = wxINT32_SWAP_ON_BE(dbuf[0]);
             gmask = wxINT32_SWAP_ON_BE(dbuf[1]);
             bmask = wxINT32_SWAP_ON_BE(dbuf[2]);
@@ -573,6 +663,9 @@ bool wxBMPHandler::DoLoadDib(wxImage * image, int width, int height,
             rmask = 0x00FF0000;
             gmask = 0x0000FF00;
             bmask = 0x000000FF;
+            amask = 0xFF000000;
+
+            ashift = 24;
             rshift = 16;
             gshift = 8;
             bshift = 0;
@@ -586,7 +679,16 @@ bool wxBMPHandler::DoLoadDib(wxImage * image, int width, int height,
      * Reading the image data
      */
     if ( IsBmp )
-        stream.SeekI(bmpOffset); // else icon, just carry on
+    {
+        // NOTE: seeking a positive amount in wxFromCurrent mode allows us to
+        //       load even non-seekable streams (see wxInputStream::SeekI docs)!
+        const wxFileOffset pos = stream.TellI();
+        if ( pos == wxInvalidOffset ||
+             (bmpOffset > pos &&
+              stream.SeekI(bmpOffset - pos, wxFromCurrent) == wxInvalidOffset) )
+            return false;
+        //else: icon, just carry on
+    }
 
     unsigned char *data = ptr;
 
@@ -602,27 +704,35 @@ bool wxBMPHandler::DoLoadDib(wxImage * image, int width, int height,
         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-- )
+    // flag indicating if we have any not fully transparent alpha values: this
+    // is used to account for the bitmaps which use 32bpp format (normally
+    // meaning that they have alpha channel) but have only zeroes in it so that
+    // without this hack they appear fully transparent -- and as this is
+    // unlikely intentional, we consider that they don't have alpha at all in
+    // this case (see #10915)
+    bool hasValidAlpha = false;
+
+    for ( int row = 0; row < height; row++ )
     {
+        int line = isUpsideDown ? height - 1 - row : row;
+
         int linepos = 0;
-        for ( column = 0; column < width ; )
+        for ( int column = 0; column < width ; )
         {
             if ( bpp < 16 )
             {
-                int index = 0;
                 linepos++;
                 aByte = stream.GetC();
+                if ( !stream.IsOk() )
+                    return false;
+
                 if ( bpp == 1 )
                 {
-                    int bit = 0;
-                    for (bit = 0; bit < 8 && column < width; bit++)
+                    for (int bit = 0; bit < 8 && column < width; bit++)
                     {
-                        index = ((aByte & (0x80 >> bit)) ? 1 : 0);
+                        int index = ((aByte & (0x80 >> bit)) ? 1 : 0);
                         ptr[poffset] = cmap[index].r;
                         ptr[poffset + 1] = cmap[index].g;
                         ptr[poffset + 2] = cmap[index].b;
@@ -636,25 +746,35 @@ bool wxBMPHandler::DoLoadDib(wxImage * image, int width, int height,
                         wxUint8 first;
                         first = aByte;
                         aByte = stream.GetC();
+                        if ( !stream.IsOk() )
+                            return false;
+
                         if ( first == 0 )
                         {
                             if ( aByte == 0 )
                             {
-                                if ( column > 0 )
-                                    column = width;
+                                // end of scanline marker
+                                column = width;
+                                row--;
                             }
                             else if ( aByte == 1 )
                             {
+                                // end of RLE data marker, stop decoding
                                 column = width;
-                                line = -1;
+                                row = height;
                             }
                             else if ( aByte == 2 )
                             {
+                                // delta marker, move in image
                                 aByte = stream.GetC();
+                                if ( !stream.IsOk() )
+                                    return false;
                                 column += aByte;
                                 linepos = column * bpp / 4;
                                 aByte = stream.GetC();
-                                line -= aByte; // upside down
+                                if ( !stream.IsOk() )
+                                    return false;
+                                row += aByte; // upside down
                             }
                             else
                             {
@@ -667,8 +787,10 @@ bool wxBMPHandler::DoLoadDib(wxImage * image, int width, int height,
                                     {
                                         ++readBytes ;
                                         aByte = stream.GetC();
-                                        nibble[0] = ( (aByte & 0xF0) >> 4 ) ;
-                                        nibble[1] = ( aByte & 0x0F ) ;
+                                        if ( !stream.IsOk() )
+                                            return false;
+                                        nibble[0] = (wxUint8)( (aByte & 0xF0) >> 4 ) ;
+                                        nibble[1] = (wxUint8)( aByte & 0x0F ) ;
                                     }
                                     ptr[poffset    ] = cmap[nibble[k%2]].r;
                                     ptr[poffset + 1] = cmap[nibble[k%2]].g;
@@ -678,14 +800,18 @@ bool wxBMPHandler::DoLoadDib(wxImage * image, int width, int height,
                                         linepos++;
                                 }
                                 if ( readBytes & 0x01 )
+                                {
                                     aByte = stream.GetC();
+                                    if ( !stream.IsOk() )
+                                        return false;
+                                }
                             }
                         }
                         else
                         {
                             wxUint8 nibble[2] ;
-                            nibble[0] = ( (aByte & 0xF0) >> 4 ) ;
-                            nibble[1] = ( aByte & 0x0F ) ;
+                            nibble[0] = (wxUint8)( (aByte & 0xF0) >> 4 ) ;
+                            nibble[1] = (wxUint8)( aByte & 0x0F ) ;
 
                             for ( int l = 0; l < first && column < width; l++ )
                             {
@@ -700,10 +826,9 @@ bool wxBMPHandler::DoLoadDib(wxImage * image, int width, int height,
                     }
                     else
                     {
-                        int nibble = 0;
-                        for (nibble = 0; nibble < 2 && column < width; nibble++)
+                        for (int nibble = 0; nibble < 2 && column < width; nibble++)
                         {
-                            index = ((aByte & (0xF0 >> nibble * 4)) >> (!nibble * 4));
+                            int index = ((aByte & (0xF0 >> (nibble * 4))) >> (!nibble * 4));
                             if ( index >= 16 )
                                 index = 15;
                             ptr[poffset] = cmap[index].r;
@@ -720,24 +845,35 @@ bool wxBMPHandler::DoLoadDib(wxImage * image, int width, int height,
                         unsigned char first;
                         first = aByte;
                         aByte = stream.GetC();
+                        if ( !stream.IsOk() )
+                            return false;
+
                         if ( first == 0 )
                         {
                             if ( aByte == 0 )
                             {
-                                /* column = width; */
+                                // end of scanline marker
+                                column = width;
+                                row--;
                             }
                             else if ( aByte == 1 )
                             {
+                                // end of RLE data marker, stop decoding
                                 column = width;
-                                line = -1;
+                                row = height;
                             }
                             else if ( aByte == 2 )
                             {
+                                // delta marker, move in image
                                 aByte = stream.GetC();
+                                if ( !stream.IsOk() )
+                                    return false;
                                 column += aByte;
                                 linepos = column * bpp / 8;
                                 aByte = stream.GetC();
-                                line += aByte;
+                                if ( !stream.IsOk() )
+                                    return false;
+                                row -= aByte;
                             }
                             else
                             {
@@ -746,13 +882,19 @@ bool wxBMPHandler::DoLoadDib(wxImage * image, int width, int height,
                                 {
                                     linepos++;
                                     aByte = stream.GetC();
+                                    if ( !stream.IsOk() )
+                                        return false;
                                     ptr[poffset    ] = cmap[aByte].r;
                                     ptr[poffset + 1] = cmap[aByte].g;
                                     ptr[poffset + 2] = cmap[aByte].b;
                                     column++;
                                 }
                                 if ( absolute & 0x01 )
+                                {
                                     aByte = stream.GetC();
+                                    if ( !stream.IsOk() )
+                                        return false;
+                                }
                             }
                         }
                         else
@@ -779,7 +921,8 @@ bool wxBMPHandler::DoLoadDib(wxImage * image, int width, int height,
             }
             else if ( bpp == 24 )
             {
-                stream.Read(bbuf, 3);
+                if ( !stream.ReadAll(bbuf, 3) )
+                    return false;
                 linepos += 3;
                 ptr[poffset    ] = (unsigned char)bbuf[2];
                 ptr[poffset + 1] = (unsigned char)bbuf[1];
@@ -789,48 +932,63 @@ bool wxBMPHandler::DoLoadDib(wxImage * image, int width, int height,
             else if ( bpp == 16 )
             {
                 unsigned char temp;
-                stream.Read(&aWord, 2);
+                if ( !stream.ReadAll(&aWord, 2) )
+                    return false;
                 aWord = wxUINT16_SWAP_ON_BE(aWord);
                 linepos += 2;
-                /* use the masks and calculated amonut of shift
+                /* Use the masks and calculated amount of shift
                    to retrieve the color data out of the word.  Then
                    shift it left by (8 - number of bits) such that
                    the image has the proper dynamic range */
-                temp = (aWord & rmask) >> rshift << (8-rbits);
+                temp = (unsigned char)(((aWord & rmask) >> rshift) << (8-rbits));
                 ptr[poffset] = temp;
-                temp = (aWord & gmask) >> gshift << (8-gbits);
+                temp = (unsigned char)(((aWord & gmask) >> gshift) << (8-gbits));
                 ptr[poffset + 1] = temp;
-                temp = (aWord & bmask) >> bshift << (8-bbits);
+                temp = (unsigned char)(((aWord & bmask) >> bshift) << (8-bbits));
                 ptr[poffset + 2] = temp;
                 column++;
             }
             else
             {
                 unsigned char temp;
-                stream.Read(&aDword, 4);
+                if ( !stream.ReadAll(&aDword, 4) )
+                    return false;
+
                 aDword = wxINT32_SWAP_ON_BE(aDword);
                 linepos += 4;
-                temp = (aDword & rmask) >> rshift;
+                temp = (unsigned char)((aDword & rmask) >> rshift);
                 ptr[poffset] = temp;
-                temp = (aDword & gmask) >> gshift;
+                temp = (unsigned char)((aDword & gmask) >> gshift);
                 ptr[poffset + 1] = temp;
-                temp = (aDword & bmask) >> bshift;
+                temp = (unsigned char)((aDword & bmask) >> bshift);
                 ptr[poffset + 2] = temp;
+                if ( alpha )
+                {
+                    temp = (unsigned char)((aDword & amask) >> ashift);
+                    alpha[line * width + column] = temp;
+
+                    if ( temp != wxALPHA_TRANSPARENT )
+                        hasValidAlpha = true;
+                }
                 column++;
             }
         }
         while ( (linepos < linesize) && (comp != 1) && (comp != 2) )
         {
-            stream.Read(&aByte, 1);
-            linepos += 1;
-            if ( !stream )
+            ++linepos;
+            if ( !stream.ReadAll(&aByte, 1) )
                 break;
         }
     }
 
-    delete[] cmap;
+    image->SetMask(false);
 
-    image->SetMask(FALSE);
+    // check if we had any valid alpha values in this bitmap
+    if ( alpha && !hasValidAlpha )
+    {
+        // we didn't, so finally discard the alpha channel completely
+        image->ClearAlpha();
+    }
 
     const wxStreamError err = stream.GetLastError();
     return err == wxSTREAM_NO_ERROR || err == wxSTREAM_EOF;
@@ -842,72 +1000,86 @@ bool wxBMPHandler::LoadDib(wxImage *image, wxInputStream& stream,
     wxUint16        aWord;
     wxInt32         dbuf[4];
     wxInt8          bbuf[4];
-    off_t           offset;
 
-    offset = 0; // keep gcc quiet
     if ( IsBmp )
     {
         // read the header off the .BMP format file
-
-        offset = stream.TellI();
-        if (offset == wxInvalidOffset) offset = 0;
-
-        stream.Read(bbuf, 2);
-        stream.Read(dbuf, 16);
+        if ( !stream.ReadAll(bbuf, 2) ||
+             !stream.ReadAll(dbuf, 16) )
+            return false;
     }
     else
     {
-        stream.Read(dbuf, 4);
+        if ( !stream.ReadAll(dbuf, 4) )
+            return false;
     }
     #if 0 // unused
         wxInt32 size = wxINT32_SWAP_ON_BE(dbuf[0]);
     #endif
-    offset = offset + wxINT32_SWAP_ON_BE(dbuf[2]);
+    wxFileOffset 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 ( !stream.ReadAll(dbuf, 4 * 2) )
+        return false;
+
+    int width = wxINT32_SWAP_ON_BE((int)dbuf[0]);
+    int height = wxINT32_SWAP_ON_BE((int)dbuf[1]);
     if ( !IsBmp)height = height  / 2; // for icons divide by 2
 
     if ( width > 32767 )
     {
         if (verbose)
+        {
             wxLogError( _("DIB Header: Image width > 32767 pixels for file.") );
-        return FALSE;
+        }
+        return false;
     }
     if ( height > 32767 )
     {
         if (verbose)
+        {
             wxLogError( _("DIB Header: Image height > 32767 pixels for file.") );
-        return FALSE;
+        }
+        return false;
     }
 
-    stream.Read(&aWord, 2);
+    if ( !stream.ReadAll(&aWord, 2) )
+        return false;
+
     /*
             TODO
             int planes = (int)wxUINT16_SWAP_ON_BE( aWord );
         */
-    stream.Read(&aWord, 2);
-    int bpp = (int)wxUINT16_SWAP_ON_BE(aWord);
+    if ( !stream.ReadAll(&aWord, 2) )
+        return false;
+
+    int bpp = wxUINT16_SWAP_ON_BE((int)aWord);
     if ( bpp != 1 && bpp != 4 && bpp != 8 && bpp != 16 && bpp != 24 && bpp != 32 )
     {
         if (verbose)
+        {
             wxLogError( _("DIB Header: Unknown bitdepth in file.") );
-        return FALSE;
+        }
+        return false;
     }
 
-    stream.Read(dbuf, 4 * 4);
-    int comp = (int)wxINT32_SWAP_ON_BE(dbuf[0]);
+    if ( !stream.ReadAll(dbuf, 4 * 4) )
+        return false;
+
+    int comp = wxINT32_SWAP_ON_BE((int)dbuf[0]);
     if ( comp != BI_RGB && comp != BI_RLE4 && comp != BI_RLE8 &&
          comp != BI_BITFIELDS )
     {
         if (verbose)
+        {
             wxLogError( _("DIB Header: Unknown encoding in file.") );
-        return FALSE;
+        }
+        return false;
     }
 
-    stream.Read(dbuf, 4 * 2);
-    int ncolors = (int)wxINT32_SWAP_ON_BE( dbuf[0] );
+    if ( !stream.ReadAll(dbuf, 4 * 2) )
+        return false;
+
+    int ncolors = wxINT32_SWAP_ON_BE( (int)dbuf[0] );
     if (ncolors == 0)
         ncolors = 1 << bpp;
     /* some more sanity checks */
@@ -916,17 +1088,21 @@ bool wxBMPHandler::LoadDib(wxImage *image, wxInputStream& stream,
         ((comp == BI_BITFIELDS) && (bpp != 16 && bpp != 32)))
     {
         if (verbose)
+        {
             wxLogError( _("DIB Header: Encoding doesn't match bitdepth.") );
-        return FALSE;
+        }
+        return false;
     }
 
     //read DIB; this is the BMP image or the XOR part of an icon image
     if ( !DoLoadDib(image, width, height, bpp, ncolors, comp, offset, stream,
-                    verbose, IsBmp, TRUE) )
+                    verbose, IsBmp, true) )
     {
         if (verbose)
-            wxLogError( _("Error in reading image DIB .") );
-        return FALSE;
+        {
+            wxLogError( _("Error in reading image DIB.") );
+        }
+        return false;
     }
 
     if ( !IsBmp )
@@ -935,32 +1111,39 @@ bool wxBMPHandler::LoadDib(wxImage *image, wxInputStream& stream,
         //there is no palette, so we will create one
         wxImage mask;
         if ( !DoLoadDib(&mask, width, height, 1, 2, BI_RGB, offset, stream,
-                        verbose, IsBmp, FALSE) )
+                        verbose, IsBmp, false) )
         {
             if (verbose)
+            {
                 wxLogError( _("ICO: Error in reading mask DIB.") );
-            return FALSE;
+            }
+            return false;
         }
         image->SetMaskFromImage(mask, 255, 255, 255);
 
     }
 
-    return TRUE;
+    // the resolution in the bitmap header is in meters, convert to centimeters
+    image->SetOption(wxIMAGE_OPTION_RESOLUTIONUNIT, wxIMAGE_RESOLUTION_CM);
+    image->SetOption(wxIMAGE_OPTION_RESOLUTIONX, dbuf[2]/100);
+    image->SetOption(wxIMAGE_OPTION_RESOLUTIONY, dbuf[3]/100);
+
+    return true;
 }
 
 bool wxBMPHandler::LoadFile(wxImage *image, wxInputStream& stream,
                             bool verbose, int WXUNUSED(index))
 {
     // Read a single DIB fom the file:
-    return LoadDib(image, stream, verbose, TRUE/*isBmp*/);
+    return LoadDib(image, stream, verbose, true/*isBmp*/);
 }
 
 bool wxBMPHandler::DoCanRead(wxInputStream& stream)
 {
     unsigned char hdr[2];
 
-    if ( !stream.Read(hdr, WXSIZEOF(hdr)) )
-        return FALSE;
+    if ( !stream.ReadAll(hdr, WXSIZEOF(hdr)) )     // it's ok to modify the stream position here
+        return false;
 
     // do we have the BMP file signature?
     return hdr[0] == 'B' && hdr[1] == 'M';
@@ -1007,22 +1190,25 @@ bool wxICOHandler::SaveFile(wxImage *image,
                             bool verbose)
 
 {
-    bool bResult = FALSE;
     //sanity check; icon must be less than 127 pixels high and 255 wide
     if ( image->GetHeight () > 127 )
     {
         if ( verbose )
+        {
             wxLogError(_("ICO: Image too tall for an icon."));
-        return FALSE;
+        }
+        return false;
     }
     if ( image->GetWidth () > 255 )
     {
         if ( verbose )
+        {
             wxLogError(_("ICO: Image too wide for an icon."));
-        return FALSE;
+        }
+        return false;
     }
 
-    int images = 1; // only generate one image
+    const int images = 1; // only generate one image
 
     // VS: This is a hack of sort - since ICO and CUR files are almost
     //     identical, we have all the meat in wxICOHandler and check for
@@ -1036,21 +1222,22 @@ bool wxICOHandler::SaveFile(wxImage *image,
 
     ICONDIR IconDir;
     IconDir.idReserved = 0;
-    IconDir.idType = wxUINT16_SWAP_ON_BE(type);
-    IconDir.idCount = wxUINT16_SWAP_ON_BE(images);
-    stream.Write(&IconDir.idReserved, sizeof(IconDir.idReserved));
-    stream.Write(&IconDir.idType, sizeof(IconDir.idType));
-    stream.Write(&IconDir.idCount, sizeof(IconDir.idCount));
-    if ( !stream.IsOk() )
+    IconDir.idType = wxUINT16_SWAP_ON_BE((wxUint16)type);
+    IconDir.idCount = wxUINT16_SWAP_ON_BE((wxUint16)images);
+    if ( !stream.WriteAll(&IconDir.idReserved, sizeof(IconDir.idReserved)) ||
+         !stream.WriteAll(&IconDir.idType, sizeof(IconDir.idType)) ||
+         !stream.WriteAll(&IconDir.idCount, sizeof(IconDir.idCount)) )
     {
         if ( verbose )
+        {
             wxLogError(_("ICO: Error writing the image file!"));
-        return FALSE;
+        }
+        return false;
     }
 
     // for each iamage write a description ICONDIRENTRY:
     ICONDIRENTRY icondirentry;
-    for (int i = 0; i < images; i++)
+    for (int img = 0; img < images; img++)
     {
         wxImage mask;
 
@@ -1094,44 +1281,50 @@ bool wxICOHandler::SaveFile(wxImage *image,
 
         // monochome bitmap:
         mask.SetOption(wxIMAGE_OPTION_BMP_FORMAT, wxBMP_1BPP_BW);
-        bool IsBmp = FALSE;
-        bool IsMask = FALSE;
+        bool IsBmp = false;
+        bool IsMask = false;
 
         //calculate size and offset of image and mask
         wxCountingOutputStream cStream;
-        bResult = SaveDib(image, cStream, verbose, IsBmp, IsMask);
+        bool bResult = SaveDib(image, cStream, verbose, IsBmp, IsMask);
         if ( !bResult )
         {
             if ( verbose )
+            {
                 wxLogError(_("ICO: Error writing the image file!"));
-            return FALSE;
+            }
+            return false;
         }
-        IsMask = TRUE;
+        IsMask = true;
 
         bResult = SaveDib(&mask, cStream, verbose, IsBmp, IsMask);
         if ( !bResult )
         {
             if ( verbose )
+            {
                 wxLogError(_("ICO: Error writing the image file!"));
-            return FALSE;
+            }
+            return false;
         }
         wxUint32 Size = cStream.GetSize();
 
-        // wxCountingOutputStream::Ok() always returns TRUE for now and this
+        // wxCountingOutputStream::IsOk() always returns true for now and this
         // "if" provokes VC++ warnings in optimized build
 #if 0
-        if ( !cStream.Ok() )
+        if ( !cStream.IsOk() )
         {
             if ( verbose )
+            {
                 wxLogError(_("ICO: Error writing the image file!"));
-            return FALSE;
+            }
+            return false;
         }
 #endif // 0
 
         offset = offset + sizeof(ICONDIRENTRY);
 
-        icondirentry.bWidth = image->GetWidth();
-        icondirentry.bHeight = 2 * image->GetHeight();
+        icondirentry.bWidth = (wxUint8)image->GetWidth();
+        icondirentry.bHeight = (wxUint8)(2 * image->GetHeight());
         icondirentry.bColorCount = 0;
         icondirentry.bReserved = 0;
         icondirentry.wPlanes = wxUINT16_SWAP_ON_BE(1);
@@ -1156,63 +1349,74 @@ bool wxICOHandler::SaveFile(wxImage *image,
         offset += Size;
 
         // write to stream:
-        stream.Write(&icondirentry.bWidth, sizeof(icondirentry.bWidth));
-        stream.Write(&icondirentry.bHeight, sizeof(icondirentry.bHeight));
-        stream.Write(&icondirentry.bColorCount, sizeof(icondirentry.bColorCount));
-        stream.Write(&icondirentry.bReserved, sizeof(icondirentry.bReserved));
-        stream.Write(&icondirentry.wPlanes, sizeof(icondirentry.wPlanes));
-        stream.Write(&icondirentry.wBitCount, sizeof(icondirentry.wBitCount));
-        stream.Write(&icondirentry.dwBytesInRes, sizeof(icondirentry.dwBytesInRes));
-        stream.Write(&icondirentry.dwImageOffset, sizeof(icondirentry.dwImageOffset));
-        if ( !stream.IsOk() )
+        if ( !stream.WriteAll(&icondirentry.bWidth, sizeof(icondirentry.bWidth)) ||
+             !stream.WriteAll(&icondirentry.bHeight, sizeof(icondirentry.bHeight)) ||
+             !stream.WriteAll(&icondirentry.bColorCount, sizeof(icondirentry.bColorCount)) ||
+             !stream.WriteAll(&icondirentry.bReserved, sizeof(icondirentry.bReserved)) ||
+             !stream.WriteAll(&icondirentry.wPlanes, sizeof(icondirentry.wPlanes)) ||
+             !stream.WriteAll(&icondirentry.wBitCount, sizeof(icondirentry.wBitCount)) ||
+             !stream.WriteAll(&icondirentry.dwBytesInRes, sizeof(icondirentry.dwBytesInRes)) ||
+             !stream.WriteAll(&icondirentry.dwImageOffset, sizeof(icondirentry.dwImageOffset)) )
         {
             if ( verbose )
+            {
                 wxLogError(_("ICO: Error writing the image file!"));
-            return FALSE;
+            }
+            return false;
         }
 
         // actually save it:
-        IsMask = FALSE;
+        IsMask = false;
         bResult = SaveDib(image, stream, verbose, IsBmp, IsMask);
         if ( !bResult )
         {
             if ( verbose )
+            {
                 wxLogError(_("ICO: Error writing the image file!"));
-            return FALSE;
+            }
+            return false;
         }
-        IsMask = TRUE;
+        IsMask = true;
 
         bResult = SaveDib(&mask, stream, verbose, IsBmp, IsMask);
         if ( !bResult )
         {
             if ( verbose )
+            {
                 wxLogError(_("ICO: Error writing the image file!"));
-            return FALSE;
+            }
+            return false;
         }
 
     } // end of for loop
 
-    return TRUE;
+    return true;
 }
 
 bool wxICOHandler::LoadFile(wxImage *image, wxInputStream& stream,
                             bool verbose, int index)
 {
-    stream.SeekI(0);
+    if ( stream.IsSeekable() && stream.SeekI(0) == wxInvalidOffset )
+    {
+        return false;
+    }
+
     return DoLoadFile(image, stream, verbose, index);
 }
 
 bool wxICOHandler::DoLoadFile(wxImage *image, wxInputStream& stream,
                             bool WXUNUSED(verbose), int index)
 {
-    bool bResult = FALSE;
-    bool IsBmp = FALSE;
+    bool bResult wxDUMMY_INITIALIZE(false);
+    bool IsBmp = false;
 
     ICONDIR IconDir;
 
-    off_t iPos = stream.TellI();
-    stream.Read(&IconDir, sizeof(IconDir));
+    if ( !stream.ReadAll(&IconDir, sizeof(IconDir)) )
+        return false;
+
     wxUint16 nIcons = wxUINT16_SWAP_ON_BE(IconDir.idCount);
+
     // nType is 1 for Icons, 2 for Cursors:
     wxUint16 nType = wxUINT16_SWAP_ON_BE(IconDir.idType);
 
@@ -1223,9 +1427,16 @@ bool wxICOHandler::DoLoadFile(wxImage *image, wxInputStream& stream,
     int colmax = 0;
     int iSel = wxNOT_FOUND;
 
-    for (int i = 0; i < nIcons; i++ )
+    // remember how many bytes we read from the stream:
+    wxFileOffset alreadySeeked = sizeof(IconDir);
+
+    for (unsigned int i = 0; i < nIcons; i++ )
     {
-        stream.Read(pCurrentEntry, sizeof(ICONDIRENTRY));
+        if ( !stream.ReadAll(pCurrentEntry, sizeof(ICONDIRENTRY)) )
+            return false;
+
+        alreadySeeked += stream.LastRead();
+
         // bHeight and bColorCount are wxUint8
         if ( pCurrentEntry->bWidth >= wMax )
         {
@@ -1239,6 +1450,7 @@ bool wxICOHandler::DoLoadFile(wxImage *image, wxInputStream& stream,
                 colmax = pCurrentEntry->bColorCount;
             }
         }
+
         pCurrentEntry++;
     }
 
@@ -1252,14 +1464,20 @@ bool wxICOHandler::DoLoadFile(wxImage *image, wxInputStream& stream,
     if ( iSel == wxNOT_FOUND || iSel < 0 || iSel >= nIcons )
     {
         wxLogError(_("ICO: Invalid icon index."));
-        bResult = FALSE;
+        bResult = false;
     }
     else
     {
         // seek to selected icon:
         pCurrentEntry = pIconDirEntry + iSel;
-        stream.SeekI(iPos + wxUINT32_SWAP_ON_BE(pCurrentEntry->dwImageOffset), wxFromStart);
-        bResult = LoadDib(image, stream, TRUE, IsBmp);
+
+        // NOTE: seeking a positive amount in wxFromCurrent mode allows us to
+        //       load even non-seekable streams (see wxInputStream::SeekI docs)!
+        wxFileOffset offset = wxUINT32_SWAP_ON_BE(pCurrentEntry->dwImageOffset) - alreadySeeked;
+        if (offset != 0 && stream.SeekI(offset, wxFromCurrent) == wxInvalidOffset)
+            return false;
+
+        bResult = LoadDib(image, stream, true, IsBmp);
         bool bIsCursorType = (this->GetType() == wxBITMAP_TYPE_CUR) || (this->GetType() == wxBITMAP_TYPE_ANI);
         if ( bResult && bIsCursorType && nType == 2 )
         {
@@ -1268,30 +1486,33 @@ bool wxICOHandler::DoLoadFile(wxImage *image, wxInputStream& stream,
             image->SetOption(wxIMAGE_OPTION_CUR_HOTSPOT_Y, wxUINT16_SWAP_ON_BE(pCurrentEntry->wBitCount));
         }
     }
-    delete[] pIconDirEntry;
+
+    delete [] pIconDirEntry;
+
     return bResult;
 }
 
-int wxICOHandler::GetImageCount(wxInputStream& stream)
+int wxICOHandler::DoGetImageCount(wxInputStream& stream)
 {
+    // It's ok to modify the stream position in this function.
+
+    if ( stream.IsSeekable() && stream.SeekI(0) == wxInvalidOffset )
+    {
+        return 0;
+    }
+
     ICONDIR IconDir;
-    off_t iPos = stream.TellI();
-    stream.SeekI(0);
-    stream.Read(&IconDir, sizeof(IconDir));
-    wxUint16 nIcons = wxUINT16_SWAP_ON_BE(IconDir.idCount);
-    stream.SeekI(iPos);
-    return (int)nIcons;
+
+    if ( !stream.ReadAll(&IconDir, sizeof(IconDir)) )
+        return 0;
+
+    return (int)wxUINT16_SWAP_ON_BE(IconDir.idCount);
 }
 
 bool wxICOHandler::DoCanRead(wxInputStream& stream)
 {
-    stream.SeekI(0);
-    unsigned char hdr[4];
-    if ( !stream.Read(hdr, WXSIZEOF(hdr)) )
-        return FALSE;
+    return CanReadICOOrCUR(&stream, 1 /*for identifying an icon*/);
 
-    // hdr[2] is one for an icon and two for a cursor
-    return hdr[0] == '\0' && hdr[1] == '\0' && hdr[2] == '\1' && hdr[3] == '\0';
 }
 
 #endif // wxUSE_STREAMS
@@ -1307,13 +1528,7 @@ IMPLEMENT_DYNAMIC_CLASS(wxCURHandler, wxICOHandler)
 
 bool wxCURHandler::DoCanRead(wxInputStream& stream)
 {
-    stream.SeekI(0);
-    unsigned char hdr[4];
-    if ( !stream.Read(hdr, WXSIZEOF(hdr)) )
-        return FALSE;
-
-    // hdr[2] is one for an icon and two for a cursor
-    return hdr[0] == '\0' && hdr[1] == '\0' && hdr[2] == '\2' && hdr[3] == '\0';
+    return CanReadICOOrCUR(&stream, 2 /*for identifying a cursor*/);
 }
 
 #endif // wxUSE_STREAMS
@@ -1327,160 +1542,49 @@ IMPLEMENT_DYNAMIC_CLASS(wxANIHandler, wxCURHandler)
 #if wxUSE_STREAMS
 
 bool wxANIHandler::LoadFile(wxImage *image, wxInputStream& stream,
-                            bool verbose, int index)
+                            bool WXUNUSED(verbose), int index)
 {
-    wxInt32 FCC1, FCC2;
-    wxUint32 datalen;
-
-    wxInt32 riff32;
-    memcpy( &riff32, "RIFF", 4 );
-    wxInt32 list32;
-    memcpy( &list32, "LIST", 4 );
-    wxInt32 ico32;
-    memcpy( &ico32, "icon", 4 );
-    int iIcon = 0;
-
-    stream.SeekI(0);
-    stream.Read(&FCC1, 4);
-    if ( FCC1 != riff32 )
-        return FALSE;
-
-    // we have a riff file:
-    while (stream.IsOk())
-    {
-        // we always have a data size
-        stream.Read(&datalen, 4);
-        datalen = wxINT32_SWAP_ON_BE(datalen) ;
-        //data should be padded to make even number of bytes
-        if (datalen % 2 == 1) datalen ++ ;
-        //now either data or a FCC
-        if ( (FCC1 == riff32) || (FCC1 == list32) )
-        {
-            stream.Read(&FCC2, 4);
-        }
-        else
-        {
-            if (FCC1 == ico32 && iIcon >= index)
-            {
-                return DoLoadFile(image, stream, verbose, -1);
-            }
-            else
-            {
-                stream.SeekI(stream.TellI() + datalen);
-                if ( FCC1 == ico32 )
-                    iIcon ++;
-            }
-        }
+    wxANIDecoder decoder;
+    if (!decoder.Load(stream))
+        return false;
 
-        // try to read next data chunk:
-        stream.Read(&FCC1, 4);
-    }
-    return FALSE;
+    return decoder.ConvertToImage(index != -1 ? (size_t)index : 0, image);
 }
 
 bool wxANIHandler::DoCanRead(wxInputStream& stream)
 {
-    wxInt32 FCC1, FCC2;
-    wxUint32 datalen ;
-    
-    wxInt32 riff32;
-    memcpy( &riff32, "RIFF", 4 );
-    wxInt32 list32;
-    memcpy( &list32, "LIST", 4 );
-    wxInt32 ico32;
-    memcpy( &ico32, "icon", 4 ); 
-    wxInt32 anih32;
-    memcpy( &anih32, "anih", 4 );
-    
-    stream.SeekI(0);
-    if ( !stream.Read(&FCC1, 4) )
-        return FALSE;
-
-    if ( FCC1 != riff32 )
-        return FALSE;
-
-    // we have a riff file:
-    while ( stream.IsOk() )
-    {
-        if ( FCC1 == anih32 )
-            return TRUE;
-        // we always have a data size:
-        stream.Read(&datalen, 4);
-        datalen = wxINT32_SWAP_ON_BE(datalen) ;
-        //data should be padded to make even number of bytes
-        if (datalen % 2 == 1) datalen ++ ;
-        // now either data or a FCC:
-        if ( (FCC1 == riff32) || (FCC1 == list32) )
-        {
-            stream.Read(&FCC2, 4);
-        }
-        else
-        {
-            stream.SeekI(stream.TellI() + datalen);
-        }
+    wxANIDecoder decod;
+    return decod.CanRead(stream);
+             // it's ok to modify the stream position here
+}
 
-        // try to read next data chunk:
-        if ( !stream.Read(&FCC1, 4) )
-        {
-            // reading failed -- either EOF or IO error, bail out anyhow
-            return FALSE;
-        }
-    }
+int wxANIHandler::DoGetImageCount(wxInputStream& stream)
+{
+    wxANIDecoder decoder;
+    if (!decoder.Load(stream))  // it's ok to modify the stream position here
+        return wxNOT_FOUND;
 
-    return FALSE;
+    return decoder.GetFrameCount();
 }
 
-int wxANIHandler::GetImageCount(wxInputStream& stream)
+static bool CanReadICOOrCUR(wxInputStream *stream, wxUint16 resourceType)
 {
-    wxInt32 FCC1, FCC2;
-    wxUint32 datalen ;
-
-    wxInt32 riff32;
-    memcpy( &riff32, "RIFF", 4 );
-    wxInt32 list32;
-    memcpy( &list32, "LIST", 4 );
-    wxInt32 ico32;
-    memcpy( &ico32, "icon", 4 );
-    wxInt32 anih32;
-    memcpy( &anih32, "anih", 4 );
-    
-    stream.SeekI(0);
-    stream.Read(&FCC1, 4);
-    if ( FCC1 != riff32 )
-        return wxNOT_FOUND;
+    // It's ok to modify the stream position in this function.
 
-    // we have a riff file:
-    while ( stream.IsOk() )
+    if ( stream->IsSeekable() && stream->SeekI(0) == wxInvalidOffset )
     {
-        // we always have a data size:
-        stream.Read(&datalen, 4);
-        datalen = wxINT32_SWAP_ON_BE(datalen) ;
-        //data should be padded to make even number of bytes
-        if (datalen % 2 == 1) datalen ++ ;
-        // now either data or a FCC:
-        if ( (FCC1 == riff32) || (FCC1 == list32) )
-        {
-            stream.Read(&FCC2, 4);
-        }
-        else
-        {
-            if ( FCC1 == anih32 )
-            {
-                wxUint32 *pData = new wxUint32[datalen/4];
-                stream.Read(pData, datalen);
-                int nIcons = wxINT32_SWAP_ON_BE(*(pData + 1));
-                delete[] pData;
-                return nIcons;
-            }
-            else
-                stream.SeekI(stream.TellI() + datalen);
-        }
+        return false;
+    }
 
-        // try to read next data chunk:
-        stream.Read(&FCC1, 4);
+    ICONDIR iconDir;
+    if ( !stream->ReadAll(&iconDir, sizeof(iconDir)) )
+    {
+        return false;
     }
 
-    return wxNOT_FOUND;
+    return !iconDir.idReserved // reserved, must be 0
+        && wxUINT16_SWAP_ON_BE(iconDir.idType) == resourceType // either 1 or 2
+        && iconDir.idCount; // must contain at least one image
 }
 
 #endif // wxUSE_STREAMS