X-Git-Url: https://git.saurik.com/wxWidgets.git/blobdiff_plain/dc683654a1af7f02ee87623a713a7147bcb6dd84..769c3372a2bd68c45d1a4afc8462d3b7939decb1:/src/common/imagpng.cpp diff --git a/src/common/imagpng.cpp b/src/common/imagpng.cpp index e5d7fd48a5..578d0baf6d 100644 --- a/src/common/imagpng.cpp +++ b/src/common/imagpng.cpp @@ -1,5 +1,5 @@ ///////////////////////////////////////////////////////////////////////////// -// Name: src/common/imagepng.cpp +// Name: src/common/imagpng.cpp // Purpose: wxImage PNG handler // Author: Robert Roebling // RCS-ID: $Id$ @@ -11,10 +11,6 @@ // declarations // ============================================================================ -#if defined(__GNUG__) && !defined(NO_GCC_PRAGMA) -#pragma implementation "imagpng.h" -#endif - // ---------------------------------------------------------------------------- // headers // ---------------------------------------------------------------------------- @@ -23,40 +19,31 @@ #include "wx/wxprec.h" #ifdef __BORLANDC__ - #pragma hdrstop -#endif - -#ifndef WX_PRECOMP - #include "wx/defs.h" + #pragma hdrstop #endif #if wxUSE_IMAGE && wxUSE_LIBPNG #include "wx/imagpng.h" -#include "wx/bitmap.h" -#include "wx/debug.h" -#include "wx/log.h" -#include "wx/app.h" +#include "wx/versioninfo.h" + +#ifndef WX_PRECOMP + #include "wx/log.h" + #include "wx/intl.h" + #include "wx/palette.h" + #include "wx/stream.h" +#endif + #include "png.h" -#include "wx/filefn.h" -#include "wx/wfstream.h" -#include "wx/intl.h" -#include "wx/module.h" // For memcpy #include -#ifdef __SALFORDC__ -#ifdef FAR -#undef FAR -#endif -#endif - // ---------------------------------------------------------------------------- // constants // ---------------------------------------------------------------------------- -// image can not have any transparent pixels at all, have only 100% opaque +// image cannot have any transparent pixels at all, have only 100% opaque // and/or 100% transparent pixels in which case a simple mask is enough to // store this information in wxImage or have a real alpha channel in which case // we need to have it in wxImage as well @@ -109,7 +96,9 @@ IMPLEMENT_DYNAMIC_CLASS(wxPNGHandler,wxImageHandler) #if wxUSE_STREAMS #ifndef PNGLINKAGEMODE - #ifdef __WATCOMC__ + #ifdef PNGAPI + #define PNGLINKAGEMODE PNGAPI + #elif defined(__WATCOMC__) // we need an explicit cdecl for Watcom, at least according to // // http://sf.net/tracker/index.php?func=detail&aid=651492&group_id=9863&atid=109863 @@ -160,32 +149,39 @@ struct wxPNGInfoStruct extern "C" { -void PNGLINKAGEMODE wx_PNG_stream_reader( png_structp png_ptr, png_bytep data, - png_size_t length ) +static void PNGLINKAGEMODE wx_PNG_stream_reader( png_structp png_ptr, png_bytep data, + png_size_t length ) { WX_PNG_INFO(png_ptr)->stream.in->Read(data, length); } -void PNGLINKAGEMODE wx_PNG_stream_writer( png_structp png_ptr, png_bytep data, - png_size_t length ) +static void PNGLINKAGEMODE wx_PNG_stream_writer( png_structp png_ptr, png_bytep data, + png_size_t length ) { WX_PNG_INFO(png_ptr)->stream.out->Write(data, length); } -// from pngerror.c -// so that the libpng doesn't send anything on stderr -void -PNGLINKAGEMODE wx_png_error(png_structp WXUNUSED(png_ptr), png_const_charp message) -{ - wxLogFatalError( wxString::FromAscii(message) ); -} - -void +static void PNGLINKAGEMODE wx_png_warning(png_structp png_ptr, png_const_charp message) { wxPNGInfoStruct *info = png_ptr ? WX_PNG_INFO(png_ptr) : NULL; if ( !info || info->verbose ) + { wxLogWarning( wxString::FromAscii(message) ); + } +} + +// from pngerror.c +// so that the libpng doesn't send anything on stderr +static void +PNGLINKAGEMODE wx_png_error(png_structp png_ptr, png_const_charp message) +{ + wx_png_warning(NULL, message); + + // we're not using libpng built-in jump buffer (see comment before + // wxPNGInfoStruct above) so we have to return ourselves, otherwise libpng + // would just abort + longjmp(WX_PNG_INFO(png_ptr)->jmpbuf, 1); } } // extern "C" @@ -278,6 +274,7 @@ FindMaskColour(unsigned char **lines, png_uint_32 width, png_uint_32 height, r2 = *p++; g2 = *p++; b2 = *p++; + ++p; // jump over alpha wxImageHistogramEntry& entry = h[wxImageHistogram:: MakeKey(r2, g2, b2)]; @@ -308,7 +305,7 @@ bool wxPNGHandler::DoCanRead( wxInputStream& stream ) { unsigned char hdr[4]; - if ( !stream.Read(hdr, WXSIZEOF(hdr)) ) + if ( !stream.Read(hdr, WXSIZEOF(hdr)) ) // it's ok to modify the stream position here return false; return memcmp(hdr, "\211PNG", WXSIZEOF(hdr)) == 0; @@ -383,15 +380,15 @@ void CopyDataFromPNG(wxImage *image, if ( IsTransparent(a) ) { *ptrDst++ = rMask; - *ptrDst++ = bMask; *ptrDst++ = gMask; + *ptrDst++ = bMask; break; } // else: !transparent // must be opaque then as otherwise we shouldn't be // using the mask at all - wxASSERT_MSG( IsOpaque(a), _T("logic error") ); + wxASSERT_MSG( IsOpaque(a), wxT("logic error") ); // fall through @@ -451,15 +448,15 @@ void CopyDataFromPNG(wxImage *image, if ( IsTransparent(a) ) { *ptrDst++ = rMask; - *ptrDst++ = bMask; *ptrDst++ = gMask; + *ptrDst++ = bMask; break; } else // !transparent { // must be opaque then as otherwise we shouldn't be // using the mask at all - wxASSERT_MSG( IsOpaque(a), _T("logic error") ); + wxASSERT_MSG( IsOpaque(a), wxT("logic error") ); // if we couldn't find a unique colour for the // mask, we can have real pixels with the same @@ -507,13 +504,16 @@ wxPNGHandler::LoadFile(wxImage *image, bool verbose, int WXUNUSED(index)) { - // VZ: as this function uses setjmp() the only fool proof error handling + // VZ: as this function uses setjmp() the only fool-proof error handling // method is to use goto (setjmp is not really C++ dtors friendly...) unsigned char **lines = NULL; png_infop info_ptr = (png_infop) NULL; wxPNGInfoStruct wxinfo; + png_uint_32 i, width, height = 0; + int bit_depth, color_type, interlace_type; + wxinfo.verbose = verbose; wxinfo.stream.in = &stream; @@ -522,7 +522,7 @@ wxPNGHandler::LoadFile(wxImage *image, png_structp png_ptr = png_create_read_struct ( PNG_LIBPNG_VER_STRING, - (voidp) NULL, + NULL, wx_png_error, wx_png_warning ); @@ -540,11 +540,8 @@ wxPNGHandler::LoadFile(wxImage *image, if (setjmp(wxinfo.jmpbuf)) goto error; - png_uint_32 i, width, height; - int bit_depth, color_type, interlace_type; - png_read_info( png_ptr, info_ptr ); - png_get_IHDR( png_ptr, info_ptr, &width, &height, &bit_depth, &color_type, &interlace_type, (int*) NULL, (int*) NULL ); + png_get_IHDR( png_ptr, info_ptr, &width, &height, &bit_depth, &color_type, &interlace_type, NULL, NULL ); if (color_type == PNG_COLOR_TYPE_PALETTE) png_set_expand( png_ptr ); @@ -561,25 +558,91 @@ wxPNGHandler::LoadFile(wxImage *image, image->Create((int)width, (int)height, (bool) false /* no need to init pixels */); - if (!image->Ok()) + if (!image->IsOk()) goto error; - lines = (unsigned char **)malloc( (size_t)(height * sizeof(unsigned char *)) ); + // initialize all line pointers to NULL to ensure that they can be safely + // free()d if an error occurs before all of them could be allocated + lines = (unsigned char **)calloc(height, sizeof(unsigned char *)); if ( !lines ) goto error; for (i = 0; i < height; i++) { if ((lines[i] = (unsigned char *)malloc( (size_t)(width * (sizeof(unsigned char) * 4)))) == NULL) - { - for ( unsigned int n = 0; n < i; n++ ) - free( lines[n] ); goto error; - } } png_read_image( png_ptr, lines ); png_read_end( png_ptr, info_ptr ); + +#if wxUSE_PALETTE + if (color_type == PNG_COLOR_TYPE_PALETTE) + { + png_colorp palette = NULL; + int numPalette = 0; + + (void) png_get_PLTE(png_ptr, info_ptr, &palette, &numPalette); + + unsigned char* r = new unsigned char[numPalette]; + unsigned char* g = new unsigned char[numPalette]; + unsigned char* b = new unsigned char[numPalette]; + + for (int j = 0; j < numPalette; j++) + { + r[j] = palette[j].red; + g[j] = palette[j].green; + b[j] = palette[j].blue; + } + + image->SetPalette(wxPalette(numPalette, r, g, b)); + delete[] r; + delete[] g; + delete[] b; + } +#endif // wxUSE_PALETTE + + + // set the image resolution if it's available + png_uint_32 resX, resY; + int unitType; + if (png_get_pHYs(png_ptr, info_ptr, &resX, &resY, &unitType) + == PNG_INFO_pHYs) + { + wxImageResolution res = wxIMAGE_RESOLUTION_CM; + + switch (unitType) + { + default: + wxLogWarning(_("Unknown PNG resolution unit %d"), unitType); + // fall through + + case PNG_RESOLUTION_UNKNOWN: + image->SetOption(wxIMAGE_OPTION_RESOLUTIONX, resX); + image->SetOption(wxIMAGE_OPTION_RESOLUTIONY, resY); + + res = wxIMAGE_RESOLUTION_NONE; + break; + + case PNG_RESOLUTION_METER: + /* + Convert meters to centimeters. + Use a string to not lose precision (converting to cm and then + to inch would result in integer rounding error). + If an app wants an int, GetOptionInt will convert and round + down for them. + */ + image->SetOption(wxIMAGE_OPTION_RESOLUTIONX, + wxString::FromCDouble((double) resX / 100.0, 2)); + image->SetOption(wxIMAGE_OPTION_RESOLUTIONY, + wxString::FromCDouble((double) resY / 100.0, 2)); + break; + } + + image->SetOption(wxIMAGE_OPTION_RESOLUTIONUNIT, res); + } + + png_destroy_read_struct( &png_ptr, &info_ptr, (png_infopp) NULL ); // loaded successfully, now init wxImage with this data @@ -593,15 +656,20 @@ wxPNGHandler::LoadFile(wxImage *image, error: if (verbose) + { wxLogError(_("Couldn't load a PNG image - file is corrupted or not enough memory.")); + } - if ( image->Ok() ) + if ( image->IsOk() ) { image->Destroy(); } if ( lines ) { + for ( unsigned int n = 0; n < height; n++ ) + free( lines[n] ); + free( lines ); } @@ -618,6 +686,44 @@ error: return false; } +// ---------------------------------------------------------------------------- +// SaveFile() palette helpers +// ---------------------------------------------------------------------------- + +typedef wxLongToLongHashMap PaletteMap; + +static unsigned long PaletteMakeKey(const png_color_8& clr) +{ + return (wxImageHistogram::MakeKey(clr.red, clr.green, clr.blue) << 8) | clr.alpha; +} + +static long PaletteFind(const PaletteMap& palette, const png_color_8& clr) +{ + unsigned long value = PaletteMakeKey(clr); + PaletteMap::const_iterator it = palette.find(value); + + return (it != palette.end()) ? it->second : wxNOT_FOUND; +} + +static long PaletteAdd(PaletteMap *palette, const png_color_8& clr) +{ + unsigned long value = PaletteMakeKey(clr); + PaletteMap::const_iterator it = palette->find(value); + size_t index; + + if (it == palette->end()) + { + index = palette->size(); + (*palette)[value] = index; + } + else + { + index = it->second; + } + + return index; +} + // ---------------------------------------------------------------------------- // writing PNGs // ---------------------------------------------------------------------------- @@ -639,7 +745,9 @@ bool wxPNGHandler::SaveFile( wxImage *image, wxOutputStream& stream, bool verbos if (!png_ptr) { if (verbose) + { wxLogError(_("Couldn't save PNG image.")); + } return false; } @@ -648,7 +756,9 @@ bool wxPNGHandler::SaveFile( wxImage *image, wxOutputStream& stream, bool verbos { png_destroy_write_struct( &png_ptr, (png_infopp)NULL ); if (verbose) + { wxLogError(_("Couldn't save PNG image.")); + } return false; } @@ -656,7 +766,9 @@ bool wxPNGHandler::SaveFile( wxImage *image, wxOutputStream& stream, bool verbos { png_destroy_write_struct( &png_ptr, (png_infopp)NULL ); if (verbose) + { wxLogError(_("Couldn't save PNG image.")); + } return false; } @@ -664,22 +776,119 @@ bool wxPNGHandler::SaveFile( wxImage *image, wxOutputStream& stream, bool verbos // explanation why this line is mandatory png_set_write_fn( png_ptr, &wxinfo, wx_PNG_stream_writer, NULL); - const int iColorType = image->HasOption(wxIMAGE_OPTION_PNG_FORMAT) + const int iHeight = image->GetHeight(); + const int iWidth = image->GetWidth(); + + const bool bHasPngFormatOption + = image->HasOption(wxIMAGE_OPTION_PNG_FORMAT); + + int iColorType = bHasPngFormatOption ? image->GetOptionInt(wxIMAGE_OPTION_PNG_FORMAT) : wxPNG_TYPE_COLOUR; - const int iBitDepth = image->HasOption(wxIMAGE_OPTION_PNG_BITDEPTH) - ? image->GetOptionInt(wxIMAGE_OPTION_PNG_BITDEPTH) - : 8; - - wxASSERT_MSG( iBitDepth == 8 || iBitDepth == 16, - _T("PNG bit depth must be 8 or 16") ); bool bHasAlpha = image->HasAlpha(); bool bHasMask = image->HasMask(); - bool bUseAlpha = bHasAlpha || bHasMask; + + bool bUsePalette = iColorType == wxPNG_TYPE_PALETTE +#if wxUSE_PALETTE + || (!bHasPngFormatOption && image->HasPalette() ) +#endif + ; + + png_color_8 mask; + + if (bHasMask) + { + mask.red = image->GetMaskRed(); + mask.green = image->GetMaskGreen(); + mask.blue = image->GetMaskBlue(); + mask.alpha = 0; + mask.gray = 0; + } + + PaletteMap palette; + + if (bUsePalette) + { + png_color png_rgb [PNG_MAX_PALETTE_LENGTH]; + png_byte png_trans[PNG_MAX_PALETTE_LENGTH]; + + const unsigned char *pColors = image->GetData(); + const unsigned char* pAlpha = image->GetAlpha(); + + if (bHasMask && !pAlpha) + { + // Mask must be first + PaletteAdd(&palette, mask); + } + + for (int y = 0; y < iHeight; y++) + { + for (int x = 0; x < iWidth; x++) + { + png_color_8 rgba; + + rgba.red = *pColors++; + rgba.green = *pColors++; + rgba.blue = *pColors++; + rgba.gray = 0; + rgba.alpha = (pAlpha && !bHasMask) ? *pAlpha++ : 0; + + // save in our palette + long index = PaletteAdd(&palette, rgba); + + if (index < PNG_MAX_PALETTE_LENGTH) + { + // save in libpng's palette + png_rgb[index].red = rgba.red; + png_rgb[index].green = rgba.green; + png_rgb[index].blue = rgba.blue; + png_trans[index] = rgba.alpha; + } + else + { + bUsePalette = false; + break; + } + } + } + + if (bUsePalette) + { + png_set_PLTE(png_ptr, info_ptr, png_rgb, palette.size()); + + if (bHasMask && !pAlpha) + { + wxASSERT(PaletteFind(palette, mask) == 0); + png_trans[0] = 0; + png_set_tRNS(png_ptr, info_ptr, png_trans, 1, NULL); + } + else if (pAlpha && !bHasMask) + { + png_set_tRNS(png_ptr, info_ptr, png_trans, palette.size(), NULL); + } + } + } + + /* + If saving palettised was requested but it was decided we can't use a + palette then reset the colour type to RGB. + */ + if (!bUsePalette && iColorType == wxPNG_TYPE_PALETTE) + { + iColorType = wxPNG_TYPE_COLOUR; + } + + bool bUseAlpha = !bUsePalette && (bHasAlpha || bHasMask); int iPngColorType; - if ( iColorType==wxPNG_TYPE_COLOUR ) + + if (bUsePalette) + { + iPngColorType = PNG_COLOR_TYPE_PALETTE; + iColorType = wxPNG_TYPE_PALETTE; + } + else if ( iColorType==wxPNG_TYPE_COLOUR ) { iPngColorType = bUseAlpha ? PNG_COLOR_TYPE_RGB_ALPHA : PNG_COLOR_TYPE_RGB; @@ -690,6 +899,25 @@ bool wxPNGHandler::SaveFile( wxImage *image, wxOutputStream& stream, bool verbos : PNG_COLOR_TYPE_GRAY; } + if (image->HasOption(wxIMAGE_OPTION_PNG_FILTER)) + png_set_filter( png_ptr, PNG_FILTER_TYPE_BASE, image->GetOptionInt(wxIMAGE_OPTION_PNG_FILTER) ); + + if (image->HasOption(wxIMAGE_OPTION_PNG_COMPRESSION_LEVEL)) + png_set_compression_level( png_ptr, image->GetOptionInt(wxIMAGE_OPTION_PNG_COMPRESSION_LEVEL) ); + + if (image->HasOption(wxIMAGE_OPTION_PNG_COMPRESSION_MEM_LEVEL)) + png_set_compression_mem_level( png_ptr, image->GetOptionInt(wxIMAGE_OPTION_PNG_COMPRESSION_MEM_LEVEL) ); + + if (image->HasOption(wxIMAGE_OPTION_PNG_COMPRESSION_STRATEGY)) + png_set_compression_strategy( png_ptr, image->GetOptionInt(wxIMAGE_OPTION_PNG_COMPRESSION_STRATEGY) ); + + if (image->HasOption(wxIMAGE_OPTION_PNG_COMPRESSION_BUFFER_SIZE)) + png_set_compression_buffer_size( png_ptr, image->GetOptionInt(wxIMAGE_OPTION_PNG_COMPRESSION_BUFFER_SIZE) ); + + int iBitDepth = !bUsePalette && image->HasOption(wxIMAGE_OPTION_PNG_BITDEPTH) + ? image->GetOptionInt(wxIMAGE_OPTION_PNG_BITDEPTH) + : 8; + png_set_IHDR( png_ptr, info_ptr, image->GetWidth(), image->GetHeight(), iBitDepth, iPngColorType, PNG_INTERLACE_NONE, PNG_COMPRESSION_TYPE_BASE, @@ -711,7 +939,7 @@ bool wxPNGHandler::SaveFile( wxImage *image, wxOutputStream& stream, bool verbos iElements = 1; } - if ( iPngColorType & PNG_COLOR_MASK_ALPHA ) + if ( bUseAlpha ) { sig_bit.alpha = (png_byte)iBitDepth; iElements++; @@ -720,6 +948,33 @@ bool wxPNGHandler::SaveFile( wxImage *image, wxOutputStream& stream, bool verbos if ( iBitDepth == 16 ) iElements *= 2; + // save the image resolution if we have it + int resX, resY; + switch ( GetResolutionFromOptions(*image, &resX, &resY) ) + { + case wxIMAGE_RESOLUTION_INCHES: + { + const double INCHES_IN_METER = 10000.0 / 254; + resX = int(resX * INCHES_IN_METER); + resY = int(resY * INCHES_IN_METER); + } + break; + + case wxIMAGE_RESOLUTION_CM: + resX *= 100; + resY *= 100; + break; + + case wxIMAGE_RESOLUTION_NONE: + break; + + default: + wxFAIL_MSG( wxT("unsupported image resolution units") ); + } + + if ( resX && resY ) + png_set_pHYs( png_ptr, info_ptr, resX, resY, PNG_RESOLUTION_METER ); + png_set_sBIT( png_ptr, info_ptr, &sig_bit ); png_write_info( png_ptr, info_ptr ); png_set_shift( png_ptr, &sig_bit ); @@ -733,39 +988,37 @@ bool wxPNGHandler::SaveFile( wxImage *image, wxOutputStream& stream, bool verbos return false; } - unsigned char * - pAlpha = (unsigned char *)(bHasAlpha ? image->GetAlpha() : NULL); - int iHeight = image->GetHeight(); - int iWidth = image->GetWidth(); + const unsigned char * + pAlpha = (const unsigned char *)(bHasAlpha ? image->GetAlpha() : NULL); - unsigned char uchMaskRed = bHasMask ? image->GetMaskRed() : 0; - unsigned char uchMaskGreen = bHasMask ? image->GetMaskGreen() : 0; - unsigned char uchMaskBlue = bHasMask ? image->GetMaskBlue() : 0; - unsigned char *pColors = image->GetData(); + const unsigned char *pColors = image->GetData(); for (int y = 0; y != iHeight; ++y) { unsigned char *pData = data; for (int x = 0; x != iWidth; x++) { - unsigned char uchRed = *pColors++; - unsigned char uchGreen = *pColors++; - unsigned char uchBlue = *pColors++; + png_color_8 clr; + clr.red = *pColors++; + clr.green = *pColors++; + clr.blue = *pColors++; + clr.gray = 0; + clr.alpha = (bUsePalette && pAlpha) ? *pAlpha++ : 0; // use with wxPNG_TYPE_PALETTE only switch ( iColorType ) { default: - wxFAIL_MSG( _T("unknown wxPNG_TYPE_XXX") ); + wxFAIL_MSG( wxT("unknown wxPNG_TYPE_XXX") ); // fall through case wxPNG_TYPE_COLOUR: - *pData++ = uchRed; + *pData++ = clr.red; if ( iBitDepth == 16 ) *pData++ = 0; - *pData++ = uchGreen; + *pData++ = clr.green; if ( iBitDepth == 16 ) *pData++ = 0; - *pData++ = uchBlue; + *pData++ = clr.blue; if ( iBitDepth == 16 ) *pData++ = 0; break; @@ -775,9 +1028,9 @@ bool wxPNGHandler::SaveFile( wxImage *image, wxOutputStream& stream, bool verbos // where do these coefficients come from? maybe we // should have image options for them as well? unsigned uiColor = - (unsigned) (76.544*(unsigned)uchRed + - 150.272*(unsigned)uchGreen + - 36.864*(unsigned)uchBlue); + (unsigned) (76.544*(unsigned)clr.red + + 150.272*(unsigned)clr.green + + 36.864*(unsigned)clr.blue); *pData++ = (unsigned char)((uiColor >> 8) & 0xFF); if ( iBitDepth == 16 ) @@ -786,10 +1039,14 @@ bool wxPNGHandler::SaveFile( wxImage *image, wxOutputStream& stream, bool verbos break; case wxPNG_TYPE_GREY_RED: - *pData++ = uchRed; + *pData++ = clr.red; if ( iBitDepth == 16 ) *pData++ = 0; break; + + case wxPNG_TYPE_PALETTE: + *pData++ = (unsigned char) PaletteFind(palette, clr); + break; } if ( bUseAlpha ) @@ -800,9 +1057,9 @@ bool wxPNGHandler::SaveFile( wxImage *image, wxOutputStream& stream, bool verbos if ( bHasMask ) { - if ( (uchRed == uchMaskRed) - && (uchGreen == uchMaskGreen) - && (uchBlue == uchMaskBlue) ) + if ( (clr.red == mask.red) + && (clr.green == mask.green) + && (clr.blue == mask.blue) ) uchAlpha = 0; } @@ -829,4 +1086,18 @@ bool wxPNGHandler::SaveFile( wxImage *image, wxOutputStream& stream, bool verbos #endif // wxUSE_STREAMS +/*static*/ wxVersionInfo wxPNGHandler::GetLibraryVersionInfo() +{ + // The version string seems to always have a leading space and a trailing + // new line, get rid of them both. + wxString str = png_get_header_version(NULL) + 1; + str.Replace("\n", ""); + + return wxVersionInfo("libpng", + PNG_LIBPNG_VER_MAJOR, + PNG_LIBPNG_VER_MINOR, + PNG_LIBPNG_VER_RELEASE, + str); +} + #endif // wxUSE_LIBPNG