+%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
+%% Name: image.tex
+%% Purpose: wxImage documentation
+%% Author: wxWidgets Team
+%% Modified by:
+%% Created:
+%% RCS-ID: $Id$
+%% Copyright: (c) wxWidgets Team
+%% License: wxWindows license
+%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
+
\section{\class{wxImage}}\label{wximage}
This class encapsulates a platform-independent image. An image can be created
via image format handlers. Functions are available to set and get image bits, so
it can be used for basic image manipulation.
-A wxImage cannot (currently) be drawn directly to a \helpref{wxDC}{wxdc}. Instead,
+A wxImage cannot (currently) be drawn directly to a \helpref{wxDC}{wxdc}. Instead,
a platform-specific \helpref{wxBitmap}{wxbitmap} object must be created from it using
-the \helpref{wxBitmap::wxBitmap(wxImage,int depth)}{wxbitmapctor} constructor.
+the \helpref{wxBitmap::wxBitmap(wxImage,int depth)}{wxbitmapctor} constructor.
This bitmap can then
be drawn in a device context, using \helpref{wxDC::DrawBitmap}{wxdcdrawbitmap}.
Starting from wxWidgets 2.5.0 wxImage supports alpha channel data, that is in
addition to a byte for the red, green and blue colour components for each pixel
-it also stores a byte representing the pixel opacity. The alpha value of $0$
-corresponds to a transparent pixel (null opacity) while the value of $255$
+it also stores a byte representing the pixel opacity. An alpha value of $0$
+corresponds to a transparent pixel (null opacity) while a value of $255$
means that the pixel is 100\% opaque.
-Unlike the RGB data, not all images have the alpha channel and before using
+Unlike RGB data, not all images have an alpha channel and before using
\helpref{GetAlpha}{wximagegetalpha} you should check if this image contains
-alpha value with \helpref{HasAlpha}{wximagehasalpha}. In fact, currently only
-images loaded from PNG files with transparency information will have alpha
-channel but support for it will be added to the other formats as well (as well
-as support for saving images with alpha channel which is not still implemented
-either).
+an alpha channel with \helpref{HasAlpha}{wximagehasalpha}. Note that currently only
+images loaded from PNG files with transparency information will have an alpha
+channel but alpha support will be added to the other formats as well (as well
+as support for saving images with alpha channel which also isn't implemented).
\wxheading{Available image handlers}
The following image handlers are available. {\bf wxBMPHandler} is always
installed by default. To use other image formats, install the appropriate
-handler with \helpref{wxImage::AddHandler}{wximageaddhandler} or
+handler with \helpref{wxImage::AddHandler}{wximageaddhandler} or
\helpref{wxInitAllImageHandlers}{wxinitallimagehandlers}.
\twocolwidtha{5cm}%
\wxheading{See also}
-\helpref{wxBitmap}{wxbitmap},
+\helpref{wxBitmap}{wxbitmap},
\helpref{wxInitAllImageHandlers}{wxinitallimagehandlers}
\latexignore{\rtfignore{\wxheading{Members}}}
Creates an image with the given width and height. If {\it clear} is true, the new image will be initialized to black.
Otherwise, the image data will be uninitialized.
-\func{}{wxImage}{\param{int}{ width}, \param{int}{ height}, \param{unsigned char*}{ data}, \param{bool}{ static\_data=false}}
+\func{}{wxImage}{\param{int}{ width}, \param{int}{ height}, \param{unsigned char*}{ data}, \param{bool}{ static\_data = \false}}
-Creates an image from given data with the given width and height. If
+Creates an image from given data with the given width and height. If
{\it static\_data} is true, then wxImage will not delete the actual
image data in its destructor, otherwise it will free it by calling
{\it free()}.
Loads an image from an input stream.
+\func{}{wxImage}{\param{const char** }{xpmData}}
+
+Creates an image from XPM data.
+
\wxheading{Parameters}
\docparam{width}{Specifies the width of the image.}
\docparam{mimetype}{MIME type string (for example 'image/jpeg')}
\docparam{index}{Index of the image to load in the case that the image file contains multiple images.
-This is only used by GIF, ICO and TIFF handlers. The default value (-1) means
-"choose the default image" and is interpreted as the first image (index=0) by
+This is only used by GIF, ICO and TIFF handlers. The default value (-1) means
+"choose the default image" and is interpreted as the first image (index=0) by
the GIF and TIFF handler and as the largest and most colourful one by the ICO handler.}
+\docparam{xpmData}{A pointer to XPM image data.}
+
\wxheading{Remarks}
Depending on how wxWidgets has been configured, not all formats may be available.
Note: any handler other than BMP must be previously
-initialized with \helpref{wxImage::AddHandler}{wximageaddhandler} or
+initialized with \helpref{wxImage::AddHandler}{wximageaddhandler} or
\helpref{wxInitAllImageHandlers}{wxinitallimagehandlers}.
-Note: you can use \helpref{GetOptionInt}{wximagegetoptionint} to get the
+Note: you can use \helpref{GetOptionInt}{wximagegetoptionint} to get the
hotspot for loaded cursor file:
\begin{verbatim}
int hotspot_x = image.GetOptionInt(wxIMAGE_OPTION_CUR_HOTSPOT_X);
\constfunc{unsigned long}{ComputeHistogram}{\param{wxImageHistogram\& }{histogram}}
-Computes the histogram of the image. {\it histogram} is a reference to
-wxImageHistogram object. wxImageHistogram is a specialization of
+Computes the histogram of the image. {\it histogram} is a reference to
+wxImageHistogram object. wxImageHistogram is a specialization of
\helpref{wxHashMap}{wxhashmap} "template" and is defined as follows:
\begin{verbatim}
\membersection{wxImage::ConvertAlphaToMask}\label{wximageconvertalphatomask}
-\func{bool}{ConvertAlphaToMask}{\param{unsigned char}{ threshold = 128}}
+\func{bool}{ConvertAlphaToMask}{\param{unsigned char}{ threshold = $128$}}
If the image has alpha channel, this method converts it to mask. All pixels
with alpha value less than \arg{threshold} are replaced with mask colour
\wxheading{Return value}
-\false if FindFirstUnusedColour returns \false, \true otherwise.
+\false if FindFirstUnusedColour returns \false, \true otherwise.
\membersection{wxImage::ConvertToBitmap}\label{wximageconverttobitmap}
(which takes wxImage and depth as its arguments) instead.
+\membersection{wxImage::ConvertToGreyscale}\label{wximageconverttogreyscale}
+
+\constfunc{wxImage}{ConvertToGreyscale}{\param{double}{ lr = 0.299}, \param{double}{ lg = 0.587}, \param{double}{ lb = 0.114}}
+
+Returns a greyscale version of the image. The returned image uses the luminance
+component of the original to calculate the greyscale. Defaults to using
+ITU-T BT.601 when converting to YUV, where every pixel equals
+(R * {\it lr}) + (G * {\it lg}) + (B * {\it lb}).
+
+
\membersection{wxImage::ConvertToMono}\label{wxbitmapconverttomono}
\constfunc{wxImage}{ConvertToMono}{\param{unsigned char}{ r}, \param{unsigned char}{ g}, \param{unsigned char}{ b}}
Returns monochromatic version of the image. The returned image has white
-colour where the original has {\it (r,g,b)} colour and black colour
+colour where the original has {\it (r,g,b)} colour and black colour
everywhere else.
Example:
\begin{verbatim}
- wxFileDialog FileDlg( this, "Choose Image", ::wxGetWorkingDirectory(), "", _("Image Files ") + wxImage::GetImageExtWildcard(), wxOPEN );
+ wxFileDialog FileDlg( this, "Choose Image", ::wxGetCwd(), "", _("Image Files ") + wxImage::GetImageExtWildcard(), wxOPEN );
\end{verbatim}
\wxheading{See also}
\func{static int}{GetImageCount}{\param{wxInputStream\&}{ stream}, \param{long}{ type = wxBITMAP\_TYPE\_ANY}}
-If the image file contains more than one image and the image handler is capable
+If the image file contains more than one image and the image handler is capable
of retrieving these individually, this function will return the number of
available images.
Gets the red value of the mask colour.
+\membersection{wxImage::GetOrFindMaskColour}\label{wximagegetgetorsetmaskcolour}
+
+\constfunc{bool}{GetOrFindMaskColour}{\param{unsigned char}{ *r}, \param{unsigned char}{ *g}, \param{unsigned char}{ *b}}
+
+Get the current mask colour or find a suitable unused colour that could be
+used as a mask colour. Returns {\tt true} if the image currently has a mask.
+
+
\membersection{wxImage::GetPalette}\label{wximagegetpalette}
\constfunc{const wxPalette\&}{GetPalette}{\void}
\constfunc{wxImage}{GetSubImage}{\param{const wxRect\&}{ rect}}
-Returns a sub image of the current one as long as the rect belongs entirely to
+Returns a sub image of the current one as long as the rect belongs entirely to
the image.
\helpref{wxImage::GetHeight}{wximagegetheight}
+\membersection{HSVValue::HSVValue}\label{hsvvaluehsvvalue}
+
+\func{}{HSVValue}{\param{double }{h = 0.0}, \param{double }{s = 0.0}, \param{double }{v = 0.0}}
+
+Constructor for HSVValue, an object that contains values for hue, saturation and value which
+represent the value of a color. It is used by \helpref{wxImage::HSVtoRGB}{wximagehsvtorgb}
+and \helpref{wxImage::RGBtoHSV}{wximagergbtohsv}, which
+converts between HSV color space and RGB color space.
+
+\pythonnote{use wxImage\_HSVValue in wxPython}
+
+
+
+\membersection{wxImage::HSVtoRGB}\label{wximagehsvtorgb}
+
+\func{wxImage::RGBValue}{HSVtoRGB}{\param{const HSVValue \& }{hsv}}
+
+Converts a color in HSV color space to RGB color space.
+
+
\membersection{wxImage::HasAlpha}\label{wximagehasalpha}
\constfunc{bool}{HasAlpha}{\void}
Gets a user-defined option as an integer. The function is case-insensitive to {\it name}.
-If the given option is not present, the function returns $0$. Use
+If the given option is not present, the function returns $0$. Use
\helpref{wxImage::HasOption}{wximagehasoption} is $0$ is a possibly valid value
for the option.
+Options for wxPNGHandler
+\twocolwidtha{5cm}%
+\begin{twocollist}
+\twocolitem{wxIMAGE\_OPTION\_PNG\_FORMAT}{Format for saving a PNG file.}
+\twocolitem{wxIMAGE\_OPTION\_PNG\_BITDEPTH}{Bit depth for every channel (R/G/B/A).}
+\end{twocollist}
+
+Supported values for wxIMAGE\_OPTION\_PNG\_FORMAT:
+\twocolwidtha{5cm}%
+\begin{twocollist}
+\twocolitem{wxPNG\_TYPE\_COLOUR}{Stores RGB image.}
+\twocolitem{wxPNG\_TYPE\_GREY}{Stores grey image, converts from RGB.}
+\twocolitem{wxPNG\_TYPE\_GREY\_RED}{Stores grey image, uses red value as grey.}
+\end{twocollist}
+
+
\wxheading{See also}
\helpref{wxImage::SetOption}{wximagesetoption},\rtfsp
\wxheading{See also}
-\helpref{wxImageHandler}{wximagehandler},
+\helpref{wxImageHandler}{wximagehandler},
\helpref{wxInitAllImageHandlers}{wxinitallimagehandlers}
\helpref{wxImageHandler}{wximagehandler}
+\membersection{wxImage::IsTransparent}\label{wximageistransparent}
+
+\constfunc{bool}{IsTransparent}{\param{int }{x}, \param{int }{y}, \param{unsigned char}{ threshold = $128$}}
+
+Returns \true if the given pixel is transparent, i.e. either has the mask
+colour if this image has a mask or if this image has alpha channel and alpha
+value of this pixel is strictly less than \arg{threshold}.
+
+
\membersection{wxImage::LoadFile}\label{wximageloadfile}
\func{bool}{LoadFile}{\param{const wxString\&}{ name}, \param{long}{ type = wxBITMAP\_TYPE\_ANY}, \param{int}{ index = -1}}
\docparam{mimetype}{MIME type string (for example 'image/jpeg')}
\docparam{index}{Index of the image to load in the case that the image file contains multiple images.
-This is only used by GIF, ICO and TIFF handlers. The default value (-1) means
-"choose the default image" and is interpreted as the first image (index=0) by
+This is only used by GIF, ICO and TIFF handlers. The default value (-1) means
+"choose the default image" and is interpreted as the first image (index=0) by
the GIF and TIFF handler and as the largest and most colourful one by the ICO handler.}
\wxheading{Remarks}
Depending on how wxWidgets has been configured, not all formats may be available.
-Note: you can use \helpref{GetOptionInt}{wximagegetoptionint} to get the
+Note: you can use \helpref{GetOptionInt}{wximagegetoptionint} to get the
hotspot for loaded cursor file:
\begin{verbatim}
int hotspot_x = image.GetOptionInt(wxIMAGE_OPTION_CUR_HOTSPOT_X);
Returns true if image data is present.
+\membersection{RGBValue::RGBValue}\label{rgbvaluergbvalue}
+
+\func{}{RGBValue}{\param{unsigned char }{r = 0}, \param{unsigned char }{g = 0}, \param{unsigned char }{b = 0}}
+
+Constructor for RGBValue, an object that contains values for red, green and blud which
+represent the value of a color. It is used by \helpref{wxImage::HSVtoRGB}{wximagehsvtorgb}
+and \helpref{wxImage::RGBtoHSV}{wximagergbtohsv}, which
+converts between HSV color space and RGB color space.
+
+\pythonnote{use wxImage\_RGBValue in wxPython}
+
+
+\membersection{wxImage::RGBtoHSV}\label{wximagergbtohsv}
+
+\func{wxImage::HSVValue}{RGBtoHSV}{\param{const RGBValue\& }{rgb}}
+
+Converts a color in RGB color space to HSV color space.
+
+
\membersection{wxImage::RemoveHandler}\label{wximageremovehandler}
\func{static bool}{RemoveHandler}{\param{const wxString\& }{name}}
\func{wxImage \&}{Rescale}{\param{int}{ width}, \param{int}{ height}}
-Changes the size of the image in-place: after a call to this function, the
-image will have the given width and height.
+Changes the size of the image in-place by scaling it: after a call to this function,
+the image will have the given width and height.
Returns the (modified) image itself.
\helpref{Scale}{wximagescale}
+\membersection{wxImage::Resize}\label{wximageresize}
+
+\func{wxImage \&}{Resize}{\param{const wxSize\&}{ size}, \param{const wxPoint&}{ pos}, \param{int}{ red = -1}, \param{int}{ green = -1}, \param{int}{ blue = -1}}
+
+Changes the size of the image in-place without scaling it by adding either a border
+with the given colour or cropping as necessary. The image is pasted into a new
+image with the given {\it size} and background colour at the position {\it pos}
+relative to the upper left of the new image. If {\it red = green = blue = -1}
+then use either the current mask colour if set or find, use, and set a
+suitable mask colour for any newly exposed areas.
+
+Returns the (modified) image itself.
+
+\wxheading{See also}
+
+\helpref{Size}{wximagesize}
+
+
\membersection{wxImage::Rotate}\label{wximagerotate}
\func{wxImage}{Rotate}{\param{double}{ angle}, \param{const wxPoint\& }{rotationCentre},
Returns the rotated image, leaving this image intact.
+\membersection{wxImage::RotateHue}\label{wximagerotatehue}
+
+\func{void}{RotateHue}{\param{double}{ angle}}
+
+Rotates the hue of each pixel in the image by {\it angle}, which is a double in
+the range of -1.0 to +1.0, where -1.0 corresponds to -360 degrees and +1.0 corresponds
+to +360 degrees.
+
+
\membersection{wxImage::Rotate90}\label{wximagerotate90}
\constfunc{wxImage}{Rotate90}{\param{bool}{ clockwise = true}}
Depending on how wxWidgets has been configured, not all formats may be available.
-Note: you can use \helpref{GetOptionInt}{wximagegetoptionint} to set the
-hotspot before saving an image into a cursor file (default hotspot is in
+Note: you can use \helpref{GetOptionInt}{wximagegetoptionint} to set the
+hotspot before saving an image into a cursor file (default hotspot is in
the centre of the image):
\begin{verbatim}
image.SetOption(wxIMAGE_OPTION_CUR_HOTSPOT_X, hotspotX);
is to blit a wxMemoryDC into another wxMemoryDC.
It may be mentioned that the GTK port uses this function internally
-to scale bitmaps when using mapping modes in wxDC.
+to scale bitmaps when using mapping modes in wxDC.
Example:
\helpref{Rescale}{wximagerescale}
+\membersection{wxImage::Size}\label{wximagesize}
+
+\constfunc{wxImage}{Size}{\param{const wxSize\&}{ size}, \param{const wxPoint&}{ pos}, \param{int}{ red = -1}, \param{int}{ green = -1}, \param{int}{ blue = -1}}
+
+Returns a resized version of this image without scaling it by adding either a border
+with the given colour or cropping as necessary. The image is pasted into a new
+image with the given {\it size} and background colour at the position {\it pos}
+relative to the upper left of the new image. If {\it red = green = blue = -1}
+then use either the current mask colour if set or find, use, and set a
+suitable mask colour for any newly exposed areas.
+
+\wxheading{See also}
+
+\helpref{Resize}{wximageresize}
+
+
\membersection{wxImage::SetAlpha}\label{wximagesetalpha}
-\func{void}{SetAlpha}{\param{unsigned char *}{alpha = {\tt NULL}}}
+\func{void}{SetAlpha}{\param{unsigned char *}{alpha = {\tt NULL}},\param{bool}{ static\_data = \false}}
This function is similar to \helpref{SetData}{wximagesetdata} and has similar
restrictions. The pointer passed to it may however be {\tt NULL} in which case
the function will allocate the alpha array internally -- this is useful to add
-alpha channel data to an image which doesn't have any. If the pointer is not
-{\tt NULL}, it must have one byte for each image pixel and be allocated with
-{\tt malloc()}. wxImage takes ownership of the pointer and will free it.
+alpha channel data to an image which doesn't have any. If the pointer is not
+{\tt NULL}, it must have one byte for each image pixel and be allocated with
+{\tt malloc()}. wxImage takes ownership of the pointer and will free it unless
+\arg{static\_data} parameter is set to \true -- in this case the caller should
+do it.
\func{void}{SetAlpha}{\param{int }{x}, \param{int }{y}, \param{unsigned char }{alpha}}
Sets image's mask so that the pixels that have RGB value of {\it mr,mg,mb}
in {\it mask} will be masked in the image. This is done by first finding an
unused colour in the image, setting this colour as the mask colour and then
-using this colour to draw all pixels in the image who corresponding pixel
+using this colour to draw all pixels in the image who corresponding pixel
in {\it mask} has given RGB value.
\wxheading{Return value}
Returns false if {\it mask} does not have same dimensions as the image or if
-there is no unused colour left. Returns true if the mask was successfully
+there is no unused colour left. Returns true if the mask was successfully
applied.
\wxheading{Notes}
Sets the pixel at the given coordinate. This routine performs bounds-checks
for the coordinate so it can be considered a safe way to manipulate the
data, but in some cases this might be too slow so that the data will have to
-be set directly. In that case you will have to get access to the image data
+be set directly. In that case you will have to get access to the image data
using the \helpref{GetData}{wximagegetdata} method.
+\membersection{wxImage::SetRGB}\label{wximagesetrgbrect}
+
+\func{void}{SetRGB}{\param{wxRect \& }{rect}, \param{unsigned char }{red}, \param{unsigned char }{green}, \param{unsigned char }{blue}}
+
+Sets the colour of the pixels within the given rectangle. This routine performs
+bounds-checks for the coordinate so it can be considered a safe way to manipulate the
+data.
+
+
\membersection{wxImage::operator $=$}\label{wximageassign}
\func{wxImage\& }{operator $=$}{\param{const wxImage\& }{image}}
\wxheading{See also}
-\helpref{wxImage}{wximage},
+\helpref{wxImage}{wximage},
\helpref{wxInitAllImageHandlers}{wxinitallimagehandlers}
\latexignore{\rtfignore{\wxheading{Members}}}
\func{int}{GetImageCount}{\param{wxInputStream\&}{ stream}}
-If the image file contains more than one image and the image handler is capable
+If the image file contains more than one image and the image handler is capable
of retrieving these individually, this function will return the number of
available images.
\wxheading{See also}
-\helpref{wxImage::LoadFile}{wximageloadfile},
-\helpref{wxImage::SaveFile}{wximagesavefile},
+\helpref{wxImage::LoadFile}{wximageloadfile},
+\helpref{wxImage::SaveFile}{wximagesavefile},
\helpref{wxImageHandler::SaveFile}{wximagehandlersavefile}
\wxheading{See also}
-\helpref{wxImage::LoadFile}{wximageloadfile},
-\helpref{wxImage::SaveFile}{wximagesavefile},
+\helpref{wxImage::LoadFile}{wximageloadfile},
+\helpref{wxImage::SaveFile}{wximagesavefile},
\helpref{wxImageHandler::LoadFile}{wximagehandlerloadfile}
\wxheading{Parameters}
\docparam{name}{Handler type.}
-
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