#define wxIMAGE_OPTION_PNG_FORMAT wxT("PngFormat")
#define wxIMAGE_OPTION_PNG_BITDEPTH wxT("PngBitDepth")
+#define wxIMAGE_OPTION_PNG_FILTER wxT("PngF")
+#define wxIMAGE_OPTION_PNG_COMPRESSION_LEVEL wxT("PngZL")
+#define wxIMAGE_OPTION_PNG_COMPRESSION_MEM_LEVEL wxT("PngZM")
+#define wxIMAGE_OPTION_PNG_COMPRESSION_STRATEGY wxT("PngZS")
+#define wxIMAGE_OPTION_PNG_COMPRESSION_BUFFER_SIZE wxT("PngZB")
enum
{
Gets a user-defined string-valued option.
Currently the only defined string option is
- @li wxIMAGE_OPTION_FILENAME: The name of the file from which the image
+ @li @c wxIMAGE_OPTION_FILENAME: The name of the file from which the image
was loaded.
- @see SetOption(), GetOptionInt(), HasOption()
-
@param name
The name of the option, case-insensitive.
@return
The value of the option or an empty string if not found. Use
HasOption() if an empty string can be a valid option value.
+
+ @see SetOption(), GetOptionInt(), HasOption()
*/
wxString GetOption(const wxString& name) const;
Use HasOption() is 0 is a possibly valid value for the option.
Generic options:
- @li wxIMAGE_OPTION_MAX_WIDTH and wxIMAGE_OPTION_MAX_HEIGHT: If either
+ @li @c wxIMAGE_OPTION_MAX_WIDTH and @c wxIMAGE_OPTION_MAX_HEIGHT: If either
of these options is specified, the loaded image will be scaled down
(preserving its aspect ratio) so that its width is less than the
max width given if it is not 0 @em and its height is less than the
handler, this is still what happens however). These options must be
set before calling LoadFile() to have any effect.
- @li wxIMAGE_OPTION_QUALITY: JPEG quality used when saving. This is an
+ @li @c wxIMAGE_OPTION_QUALITY: JPEG quality used when saving. This is an
integer in 0..100 range with 0 meaning very poor and 100 excellent
(but very badly compressed). This option is currently ignored for
the other formats.
- @li wxIMAGE_OPTION_RESOLUTIONUNIT: The value of this option determines
+ @li @c wxIMAGE_OPTION_RESOLUTIONUNIT: The value of this option determines
whether the resolution of the image is specified in centimetres or
inches, see wxImageResolution enum elements.
- @li wxIMAGE_OPTION_RESOLUTION, wxIMAGE_OPTION_RESOLUTIONX and
- wxIMAGE_OPTION_RESOLUTIONY: These options define the resolution of
- the image in the units corresponding to wxIMAGE_OPTION_RESOLUTIONUNIT
+ @li @c wxIMAGE_OPTION_RESOLUTION, @c wxIMAGE_OPTION_RESOLUTIONX and
+ @c wxIMAGE_OPTION_RESOLUTIONY: These options define the resolution of
+ the image in the units corresponding to @c wxIMAGE_OPTION_RESOLUTIONUNIT
options value. The first option can be set before saving the image
to set both horizontal and vertical resolution to the same value.
The X and Y options are set by the image handlers if they support
after loading the image.
Options specific to wxPNGHandler:
- @li wxIMAGE_OPTION_PNG_FORMAT: Format for saving a PNG file, see
+ @li @c wxIMAGE_OPTION_PNG_FORMAT: Format for saving a PNG file, see
wxImagePNGType for the supported values.
- @li wxIMAGE_OPTION_PNG_BITDEPTH: Bit depth for every channel (R/G/B/A).
-
- @see SetOption(), GetOption()
+ @li @c wxIMAGE_OPTION_PNG_BITDEPTH: Bit depth for every channel (R/G/B/A).
+ @li @c wxIMAGE_OPTION_PNG_FILTER: Filter for saving a PNG file, see libpng
+ (http://www.libpng.org/pub/png/libpng-1.2.5-manual.html) for possible values
+ (e.g. PNG_FILTER_NONE, PNG_FILTER_SUB, PNG_FILTER_UP, etc).
+ @li @c wxIMAGE_OPTION_PNG_COMPRESSION_LEVEL: Compression level (0..9) for
+ saving a PNG file. An high value creates smaller-but-slower PNG file.
+ Note that unlike other formats (e.g. JPEG) the PNG format is always
+ lossless and thus this compression level doesn't tradeoff the image
+ quality.
+ @li @c wxIMAGE_OPTION_PNG_COMPRESSION_MEM_LEVEL: Compression memory usage
+ level (1..9) for saving a PNG file. An high value means the saving
+ process consumes more memory, but may create smaller PNG file.
+ @li @c wxIMAGE_OPTION_PNG_COMPRESSION_STRATEGY: Possible values are 0 for
+ default strategy, 1 for filter, and 2 for Huffman-only.
+ You can use OptiPNG (http://optipng.sourceforge.net/) to get a suitable
+ value for your application.
+ @li @c wxIMAGE_OPTION_PNG_COMPRESSION_BUFFER_SIZE: Internal buffer size
+ (in bytes) for saving a PNG file. Ideally this should be as big as
+ the resulting PNG file. Use this option if your application produces
+ images with small size variation.
@param name
The name of the option, case-insensitive.
@return
- The value of the option or 0 if not found. Use HasOption() if 0
- can be a valid option value.
+ The value of the option or 0 if not found.
+ Use HasOption() if 0 can be a valid option value.
+
+ @see SetOption(), GetOption()
*/
int GetOptionInt(const wxString& name) const;
Returns @true if the given option is present.
The function is case-insensitive to @a name.
+ The lists of the currently supported options are in GetOption() and
+ GetOptionInt() function docs.
+
@see SetOption(), GetOption(), GetOptionInt()
*/
bool HasOption(const wxString& name) const;
For example, when saving as a JPEG file, the option @b quality is
used, which is a number between 0 and 100 (0 is terrible, 100 is very good).
+ The lists of the currently supported options are in GetOption() and
+ GetOptionInt() function docs.
+
@see GetOption(), GetOptionInt(), HasOption()
*/
void SetOption(const wxString& name, const wxString& value);
{
image.SetOption(wxIMAGE_OPTION_PNG_FORMAT, pngvalues[sel]);
image.SetOption(wxIMAGE_OPTION_PNG_BITDEPTH, sel % 2 ? 16 : 8);
+
+ // these values are taken from OptiPNG with -o3 switch
+ const wxString compressionChoices[] =
+ {
+ _T("compression = 9, memory = 8, strategy = 0, filter = 0"),
+ _T("compression = 9, memory = 9, strategy = 0, filter = 0"),
+ _T("compression = 9, memory = 8, strategy = 1, filter = 0"),
+ _T("compression = 9, memory = 9, strategy = 1, filter = 0"),
+ _T("compression = 1, memory = 8, strategy = 2, filter = 0"),
+ _T("compression = 1, memory = 9, strategy = 2, filter = 0"),
+ _T("compression = 9, memory = 8, strategy = 0, filter = 5"),
+ _T("compression = 9, memory = 9, strategy = 0, filter = 5"),
+ _T("compression = 9, memory = 8, strategy = 1, filter = 5"),
+ _T("compression = 9, memory = 9, strategy = 1, filter = 5"),
+ _T("compression = 1, memory = 8, strategy = 2, filter = 5"),
+ _T("compression = 1, memory = 9, strategy = 2, filter = 5"),
+ };
+
+ int sel = wxGetSingleChoiceIndex(_T("Select compression option (Cancel to use default)\n"),
+ _T("PNG Compression Options"),
+ WXSIZEOF(compressionChoices),
+ compressionChoices,
+ this);
+ if (sel != -1)
+ {
+ const int zc[] = {9, 9, 9, 9, 1, 1, 9, 9, 9, 9, 1, 1};
+ const int zm[] = {8, 9, 8, 9, 8, 9, 8, 9, 8, 9, 8, 9};
+ const int zs[] = {0, 0, 1, 1, 2, 2, 0, 0, 1, 1, 2, 2};
+ const int f[] = {0x08, 0x08, 0x08, 0x08, 0x08, 0x08,
+ 0xF8, 0xF8, 0xF8, 0xF8, 0xF8, 0xF8};
+
+ image.SetOption(wxIMAGE_OPTION_PNG_COMPRESSION_LEVEL , zc[sel]);
+ image.SetOption(wxIMAGE_OPTION_PNG_COMPRESSION_MEM_LEVEL , zm[sel]);
+ image.SetOption(wxIMAGE_OPTION_PNG_COMPRESSION_STRATEGY , zs[sel]);
+ image.SetOption(wxIMAGE_OPTION_PNG_FILTER , f[sel]);
+ image.SetOption(wxIMAGE_OPTION_PNG_COMPRESSION_BUFFER_SIZE, 1048576); // 1 MB
+ }
}
}
else if ( extension == _T("cur") )
: 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) );
+
png_set_IHDR( png_ptr, info_ptr, image->GetWidth(), image->GetHeight(),
iBitDepth, iPngColorType,
PNG_INTERLACE_NONE, PNG_COMPRESSION_TYPE_BASE,
projects / wxWidgets.git / commitdiff
