#if wxUSE_IMAGE && wxUSE_LIBPNG
#include "wx/imagpng.h"
+#include "wx/versioninfo.h"
#ifndef WX_PRECOMP
#include "wx/log.h"
// 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
// First, let me describe what's the problem: libpng uses jmp_buf in
// its png_struct structure. Unfortunately, this structure is
// compiler-specific and may vary in size, so if you use libpng compiled
-// as DLL with another compiler than the main executable, it may not work
-// (this is for example the case with wxMGL port and SciTech MGL library
-// that provides custom runtime-loadable libpng implementation with jmpbuf
-// disabled altogether). Luckily, it is still possible to use setjmp() &
-// longjmp() as long as the structure is not part of png_struct.
+// as DLL with another compiler than the main executable, it may not work.
+// Luckily, it is still possible to use setjmp() & longjmp() as long as the
+// structure is not part of png_struct.
//
// Sadly, there's no clean way to attach user-defined data to png_struct.
// There is only one customizable place, png_struct.io_ptr, which is meant
// 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
{
// 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
png_structp png_ptr = png_create_read_struct
(
PNG_LIBPNG_VER_STRING,
- (voidp) NULL,
+ NULL,
wx_png_error,
wx_png_warning
);
image->Create((int)width, (int)height, (bool) false /* no need to init pixels */);
- if (!image->Ok())
+ if (!image->IsOk())
goto error;
// initialize all line pointers to NULL to ensure that they can be safely
#if wxUSE_PALETTE
if (color_type == PNG_COLOR_TYPE_PALETTE)
{
- const size_t ncolors = info_ptr->num_palette;
- unsigned char* r = new unsigned char[ncolors];
- unsigned char* g = new unsigned char[ncolors];
- unsigned char* b = new unsigned char[ncolors];
+ 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 (size_t j = 0; j < ncolors; j++)
+ for (int j = 0; j < numPalette; j++)
{
- r[j] = info_ptr->palette[j].red;
- g[j] = info_ptr->palette[j].green;
- b[j] = info_ptr->palette[j].blue;
+ r[j] = palette[j].red;
+ g[j] = palette[j].green;
+ b[j] = palette[j].blue;
}
- image->SetPalette(wxPalette(ncolors, r, g, b));
+ 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
wxLogError(_("Couldn't load a PNG image - file is corrupted or not enough memory."));
}
- if ( image->Ok() )
+ if ( image->IsOk() )
{
image->Destroy();
}
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
// ----------------------------------------------------------------------------
// 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;
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 = { 0, 0, 0, 0, 0 };
+
+ if (bHasMask)
+ {
+ mask.red = image->GetMaskRed();
+ mask.green = image->GetMaskGreen();
+ mask.blue = image->GetMaskBlue();
+ }
+
+ 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;
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,
iElements = 1;
}
- if ( iPngColorType & PNG_COLOR_MASK_ALPHA )
+ if ( bUseAlpha )
{
sig_bit.alpha = (png_byte)iBitDepth;
iElements++;
break;
default:
- wxFAIL_MSG( _T("unsupported image resolution units") );
+ wxFAIL_MSG( wxT("unsupported image resolution units") );
}
if ( resX && resY )
return false;
}
- unsigned char *
- pAlpha = (unsigned char *)(bHasAlpha ? image->GetAlpha() : NULL);
- int iHeight = image->GetHeight();
- int iWidth = image->GetWidth();
-
- unsigned char uchMaskRed = 0, uchMaskGreen = 0, uchMaskBlue = 0;
-
- if ( bHasMask )
- {
- uchMaskRed = image->GetMaskRed();
- uchMaskGreen = image->GetMaskGreen();
- uchMaskBlue = image->GetMaskBlue();
- }
+ const unsigned char *
+ pAlpha = (const unsigned char *)(bHasAlpha ? image->GetAlpha() : NULL);
- 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;
// 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 )
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 )
if ( bHasMask )
{
- if ( (uchRed == uchMaskRed)
- && (uchGreen == uchMaskGreen)
- && (uchBlue == uchMaskBlue) )
+ if ( (clr.red == mask.red)
+ && (clr.green == mask.green)
+ && (clr.blue == mask.blue) )
uchAlpha = 0;
}
#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
projects / wxWidgets.git / blobdiff