wxImage

This class encapsulates a platform-independent image. An image can be created from data, or using wxBitmap::ConvertToImage. An image can be loaded from a file in a variety of formats, and is extensible to new formats 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 wxDC. Instead, a platform-specific wxBitmap object must be created from it using the wxBitmap::wxBitmap(wxImage,int depth) constructor. This bitmap can then be drawn in a device context, using wxDC::DrawBitmap.

One colour value of the image may be used as a mask colour which will lead to the automatic creation of a wxMask object associated to the bitmap object.

Alpha channel support

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. An alpha value of corresponds to a transparent pixel (null opacity) while a value of means that the pixel is 100% opaque.

Unlike RGB data, not all images have an alpha channel and before using GetAlpha you should check if this image contains an alpha channel with HasAlpha. 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).

Available image handlers

The following image handlers are available. wxBMPHandler is always installed by default. To use other image formats, install the appropriate handler with wxImage::AddHandler or wxInitAllImageHandlers.

wxBMPHandler For loading and saving, always installed.

wxPNGHandler For loading (including alpha support) and saving.

wxJPEGHandler For loading and saving.

wxGIFHandler Only for loading, due to legal issues.

wxPCXHandler For loading and saving (see below).

wxPNMHandler For loading and saving (see below).

wxTIFFHandler For loading and saving.

wxIFFHandler For loading only.

wxXPMHandler For loading and saving.

wxICOHandler For loading and saving.

wxCURHandler For loading and saving.

wxANIHandler For loading only.

When saving in PCX format, wxPCXHandler will count the number of different colours in the image; if there are 256 or less colours, it will save as 8 bit, else it will save as 24 bit.

Loading PNMs only works for ASCII or raw RGB images. When saving in PNM format, wxPNMHandler will always save as raw RGB.

Derived from

wxObject

Include files

See also

wxBitmap, wxInitAllImageHandlers

wxImage::wxImage

wxImage(void)

Default constructor.

wxImage(const wxImage& image)

Copy constructor.

wxImage(const wxBitmap& bitmap)

(Deprecated form, use wxBitmap::ConvertToImage instead.) Constructs an image from a platform-dependent bitmap. This preserves mask information so that bitmaps and images can be converted back and forth without loss in that respect.

wxImage(int width, int height, bool clear=true)

Creates an image with the given width and height. If clear is true, the new image will be initialized to black. Otherwise, the image data will be uninitialized.

wxImage(int width, int height, unsigned char* data, bool static_data = FALSE)

Creates an image from given data with the given width and height. If static_data is true, then wxImage will not delete the actual image data in its destructor, otherwise it will free it by calling free().

wxImage(const wxString& name, long type = wxBITMAP_TYPE_ANY, int index = -1)

wxImage(const wxString& name, const wxString& mimetype, int index = -1)

Loads an image from a file.

wxImage(wxInputStream& stream, long type = wxBITMAP_TYPE_ANY, int index = -1)

wxImage(wxInputStream& stream, const wxString& mimetype, int index = -1)

Loads an image from an input stream.

wxImage(const char** xpmData)

Creates an image from XPM data.

Parameters

width: Specifies the width of the image.

height: Specifies the height of the image.

name: Name of the file from which to load the image.

stream: Opened input stream from which to load the image. Currently, the stream must support seeking.

type

May be one of the following:

wxBITMAP_TYPE_BMP Load a Windows bitmap file.

wxBITMAP_TYPE_GIF Load a GIF bitmap file.

wxBITMAP_TYPE_JPEG Load a JPEG bitmap file.

wxBITMAP_TYPE_PNG Load a PNG bitmap file.

wxBITMAP_TYPE_PCX Load a PCX bitmap file.

wxBITMAP_TYPE_PNM Load a PNM bitmap file.

wxBITMAP_TYPE_TIF Load a TIFF bitmap file.

wxBITMAP_TYPE_XPM Load a XPM bitmap file.

wxBITMAP_TYPE_ICO Load a Windows icon file (ICO).

wxBITMAP_TYPE_CUR Load a Windows cursor file (CUR).

wxBITMAP_TYPE_ANI Load a Windows animated cursor file (ANI).

wxBITMAP_TYPE_ANY Will try to autodetect the format.

mimetype: MIME type string (for example 'image/jpeg')

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 the GIF and TIFF handler and as the largest and most colourful one by the ICO handler.

xpmData: A pointer to XPM image data.

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 wxImage::AddHandler or wxInitAllImageHandlers.

Note: you can use GetOptionInt to get the hotspot for loaded cursor file:

    int hotspot_x = image.GetOptionInt(wxIMAGE_OPTION_CUR_HOTSPOT_X);
    int hotspot_y = image.GetOptionInt(wxIMAGE_OPTION_CUR_HOTSPOT_Y);

See also

wxImage::LoadFile

wxPython での注意点: Constructors supported by wxPython are:

2cm

wxImage(name, flag) Loads an image from a file

wxNullImage() Create a null image (has no size or image data)

wxEmptyImage(width, height) Creates an empty image of the given size

wxImageFromMime(name, mimetype Creates an image from the given file of the given mimetype

wxImageFromBitmap(bitmap) Creates an image from a platform-dependent bitmap

wxPerl での注意点: Constructors supported by wxPerl are:

Wx::Image->new( bitmap )
Wx::Image->new( icon )
Wx::Image->new( width, height )
Wx::Image->new( width, height, data )
Wx::Image->new( file, type, index )
Wx::Image->new( file, mimetype, index )
Wx::Image->new( stream, type, index )
Wx::Image->new( stream, mimetype, index )

wxImage::~wxImage

~wxImage(void)

Destructor.

wxImage::AddHandler

static void AddHandler(wxImageHandler* handler)

Adds a handler to the end of the static list of format handlers.

handler: A new image format handler object. There is usually only one instance of a given handler class in an application session.

See also

wxImageHandler

bool CanRead(const wxString& filename)

returns true if the current image handlers can read this file

wxPython での注意点: In wxPython this static method is named wxImage_AddHandler.

wxImage::CleanUpHandlers

static void CleanUpHandlers(void)

Deletes all image handlers.

This function is called by wxWidgets on exit.

wxImage::ComputeHistogram

unsigned long ComputeHistogram(wxImageHistogram& histogram) const

Computes the histogram of the image. histogram is a reference to wxImageHistogram object. wxImageHistogram is a specialization of wxHashMap "template" and is defined as follows:

class WXDLLEXPORT wxImageHistogramEntry
{
public:
    wxImageHistogramEntry() : index(0), value(0) {}
    unsigned long index;
    unsigned long value;
};

WX_DECLARE_EXPORTED_HASH_MAP(unsigned long, wxImageHistogramEntry,
                             wxIntegerHash, wxIntegerEqual,
                             wxImageHistogram);

Return value

Returns number of colours in the histogram.

wxImage::ConvertAlphaToMask

bool ConvertAlphaToMask(unsigned char threshold = )

If the image has alpha channel, this method converts it to mask. All pixels with alpha value less than threshold are replaced with mask colour and the alpha channel is removed. Mask colour is chosen automatically using FindFirstUnusedColour.

If the image image doesn't have alpha channel, ConvertAlphaToMask does nothing.

Return value

FALSEif FindFirstUnusedColour returns FALSE, TRUEotherwise.

wxImage::ConvertToBitmap

wxBitmap ConvertToBitmap(void) const

Deprecated, use equivalent wxBitmap constructor (which takes wxImage and depth as its arguments) instead.

wxImage::ConvertToMono

wxImage ConvertToMono(unsigned char r, unsigned char g, unsigned char b) const

Returns monochromatic version of the image. The returned image has white colour where the original has (r,g,b) colour and black colour everywhere else.

wxImage::Copy

wxImage Copy(void) const

Returns an identical copy of the image.

wxImage::Create

bool Create(int width, int height, bool clear=true)

Creates a fresh image. If clear is true, the new image will be initialized to black. Otherwise, the image data will be uninitialized.

Parameters

width: The width of the image in pixels.

height: The height of the image in pixels.

Return value

true if the call succeeded, false otherwise.

wxImage::Destroy

void Destroy(void)

Destroys the image data.

wxImage::FindFirstUnusedColour

bool FindFirstUnusedColour(unsigned char * r, unsigned char * g, unsigned char * b, unsigned char startR = 1, unsigned char startG = 0, unsigned char startB = 0)

Parameters

r,g,b: Pointers to variables to save the colour.

startR,startG,startB: Initial values of the colour. Returned colour will have RGB values equal to or greater than these.

Finds the first colour that is never used in the image. The search begins at given initial colour and continues by increasing R, G and B components (in this order) by 1 until an unused colour is found or the colour space exhausted.

Return value

Returns false if there is no unused colour left, true on success.

Notes

Note that this method involves computing the histogram, which is computationally intensive operation.

wxImage::FindHandler

static wxImageHandler* FindHandler(const wxString& name)

Finds the handler with the given name.

static wxImageHandler* FindHandler(const wxString& extension, long imageType)

Finds the handler associated with the given extension and type.

static wxImageHandler* FindHandler(long imageType)

Finds the handler associated with the given image type.

static wxImageHandler* FindHandlerMime(const wxString& mimetype)

Finds the handler associated with the given MIME type.

name: The handler name.

extension: The file extension, such as ``bmp".

imageType: The image type, such as wxBITMAP_TYPE_BMP.

mimetype: MIME type.

Return value

A pointer to the handler if found, NULL otherwise.

See also

wxImageHandler

wxImage::GetImageExtWildcard

static wxString GetImageExtWildcard(void)

Iterates all registered wxImageHandler objects, and returns a string containing file extension masks suitable for passing to file open/save dialog boxes.

Return value

The format of the returned string is "(*.ext1;*.ext2)|*.ext1;*.ext2".

It is usually a good idea to prepend a description before passing the result to the dialog.

Example:

    wxFileDialog FileDlg( this, "Choose Image", ::wxGetWorkingDirectory(), "", _("Image Files ") + wxImage::GetImageExtWildcard(), wxOPEN );

See also

wxImageHandler

wxImage::GetAlpha

unsigned char GetAlpha(int x, int y) const

Returns the alpha value for the given pixel. This function may only be called for the images with alpha channel, use HasAlpha to check for this.

The returned value is the opacity of the image, i.e. the value of corresponds to the transparent pixels while the value of - to the opaque ones.

unsigned char * GetAlpha(void) const

Returns pointer to the array storing the alpha values for this image. This pointer is NULL for the images without the alpha channel. If the image does have it, this pointer may be used to directly manipulate the alpha values which are stored as the RGB ones.

wxImage::GetBlue

unsigned char GetBlue(int x, int y) const

Returns the blue intensity at the given coordinate.

wxImage::GetData

unsigned char* GetData(void) const

Returns the image data as an array. This is most often used when doing direct image manipulation. The return value points to an array of characters in RGBRGBRGB $\ldots$ format in the top-to-bottom, left-to-right order, that is the first RGB triplet corresponds to the pixel first pixel of the first row, the second one -- to the second pixel of the first row and so on until the end of the first row, with second row following after it and so on.

You should not delete the returned pointer nor pass it to wxImage::SetData.

wxImage::GetGreen

unsigned char GetGreen(int x, int y) const

Returns the green intensity at the given coordinate.

wxImage::GetImageCount

static int GetImageCount(const wxString& filename, long type = wxBITMAP_TYPE_ANY)

static int GetImageCount(wxInputStream& stream, long type = wxBITMAP_TYPE_ANY)

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.

name: Name of the file to query.

stream: Opened input stream with image data. Currently, the stream must support seeking.

type

May be one of the following:

Return value

Number of available images. For most image handlers, this is 1 (exceptions are TIFF and ICO formats).

wxImage::GetHandlers

static wxList& GetHandlers(void)

Returns the static list of image format handlers.

See also

wxImageHandler

wxImage::GetHeight

int GetHeight(void) const

Gets the height of the image in pixels.

wxImage::GetMaskBlue

unsigned char GetMaskBlue(void) const

Gets the blue value of the mask colour.

wxImage::GetMaskGreen

unsigned char GetMaskGreen(void) const

Gets the green value of the mask colour.

wxImage::GetMaskRed

unsigned char GetMaskRed(void) const

Gets the red value of the mask colour.

wxImage::GetOrFindMaskColour

bool GetOrFindMaskColour(unsigned char *r, unsigned char *g, unsigned char *b) const

Get the current mask colour or find a suitable unused colour that could be used as a mask colour. Returns true if the image currently has a mask.

wxImage::GetPalette

const wxPalette& GetPalette(void) const

Returns the palette associated with the image. Currently the palette is only used when converting to wxBitmap under Windows.

Eventually wxImage handlers will set the palette if one exists in the image file.

wxImage::GetRed

unsigned char GetRed(int x, int y) const

Returns the red intensity at the given coordinate.

wxImage::GetSubImage

wxImage GetSubImage(const wxRect& rect) const

Returns a sub image of the current one as long as the rect belongs entirely to the image.

wxImage::GetWidth

int GetWidth(void) const

Gets the width of the image in pixels.

See also

wxImage::GetHeight

wxImage::HasAlpha

bool HasAlpha(void) const

Returns true if this image has alpha channel, false otherwise.

See also

GetAlpha, SetAlpha

wxImage::HasMask

bool HasMask(void) const

Returns true if there is a mask active, false otherwise.

wxImage::GetOption

wxString GetOption(const wxString& name) const

Gets a user-defined option. The function is case-insensitive to name.

For example, when saving as a JPEG file, the option quality is used, which is a number between 0 and 100 (0 is terrible, 100 is very good).

wxImage::GetOptionInt

int GetOptionInt(const wxString& name) const

Gets a user-defined option as an integer. The function is case-insensitive to name.

If the given option is not present, the function returns . Use wxImage::HasOption is is a possibly valid value for the option.

Options for wxPNGHandler

wxIMAGE_OPTION_PNG_FORMAT Format for saving a PNG file.

wxIMAGE_OPTION_PNG_BITDEPTH Bit depth for every channel (R/G/B/A).

Supported values for wxIMAGE_OPTION_PNG_FORMAT:

wxPNG_TYPE_COLOUR Stores RGB image.

wxPNG_TYPE_GREY Stores grey image, converts from RGB.

wxPNG_TYPE_GREY_RED Stores grey image, uses red value as grey.

wxImage::HasOption

bool HasOption(const wxString& name) const

Returns true if the given option is present. The function is case-insensitive to name.

wxImage::InitAlpha

void InitAlpha(void)

Initializes the image alpha channel data. It is an error to call it if the image already has alpha data. If it doesn't, alpha data will be by default initialized to all pixels being fully opaque. But if the image has a a mask colour, all mask pixels will be completely transparent.

wxImage::InitStandardHandlers

static void InitStandardHandlers(void)

Internal use only. Adds standard image format handlers. It only install BMP for the time being, which is used by wxBitmap.

This function is called by wxWidgets on startup, and shouldn't be called by the user.

wxImage::InsertHandler

static void InsertHandler(wxImageHandler* handler)

Adds a handler at the start of the static list of format handlers.

handler: A new image format handler object. There is usually only one instance of a given handler class in an application session.

See also

wxImageHandler

wxImage::IsTransparent

bool IsTransparent(int x, int y, unsigned char threshold = ) const

Returns TRUEif 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 threshold.

wxImage::LoadFile

bool LoadFile(const wxString& name, long type = wxBITMAP_TYPE_ANY, int index = -1)

bool LoadFile(const wxString& name, const wxString& mimetype, int index = -1)

Loads an image from a file. If no handler type is provided, the library will try to autodetect the format.

bool LoadFile(wxInputStream& stream, long type, int index = -1)

bool LoadFile(wxInputStream& stream, const wxString& mimetype, int index = -1)

Loads an image from an input stream.

Parameters

name: Name of the file from which to load the image.

stream: Opened input stream from which to load the image. Currently, the stream must support seeking.

type

One of the following values:

wxBITMAP_TYPE_BMP Load a Windows image file.

wxBITMAP_TYPE_GIF Load a GIF image file.

wxBITMAP_TYPE_JPEG Load a JPEG image file.

wxBITMAP_TYPE_PCX Load a PCX image file.

wxBITMAP_TYPE_PNG Load a PNG image file.

wxBITMAP_TYPE_PNM Load a PNM image file.

wxBITMAP_TYPE_TIF Load a TIFF image file.

wxBITMAP_TYPE_XPM Load a XPM image file.

wxBITMAP_TYPE_ICO Load a Windows icon file (ICO).

wxBITMAP_TYPE_CUR Load a Windows cursor file (CUR).

wxBITMAP_TYPE_ANI Load a Windows animated cursor file (ANI).

wxBITMAP_TYPE_ANY Will try to autodetect the format.

mimetype: MIME type string (for example 'image/jpeg')

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 the GIF and TIFF handler and as the largest and most colourful one by the ICO handler.

Remarks

Depending on how wxWidgets has been configured, not all formats may be available.

Note: you can use GetOptionInt to get the hotspot for loaded cursor file:

    int hotspot_x = image.GetOptionInt(wxIMAGE_OPTION_CUR_HOTSPOT_X);
    int hotspot_y = image.GetOptionInt(wxIMAGE_OPTION_CUR_HOTSPOT_Y);

Return value

true if the operation succeeded, false otherwise. If the optional index parameter is out of range, false is returned and a call to wxLogError() takes place.

See also

wxImage::SaveFile

wxPython での注意点: In place of a single overloaded method name, wxPython implements the following methods:

2cm

LoadFile(filename, type) Loads an image of the given type from a file

LoadMimeFile(filename, mimetype) Loads an image of the given mimetype from a file

wxPerl での注意点: Methods supported by wxPerl are:

bitmap->LoadFile( name, type )
bitmap->LoadFile( name, mimetype )

wxImage::Ok

bool Ok(void) const

Returns true if image data is present.

wxImage::RemoveHandler

static bool RemoveHandler(const wxString& name)

Finds the handler with the given name, and removes it. The handler is not deleted.

name: The handler name.

Return value

true if the handler was found and removed, false otherwise.

See also

wxImageHandler

wxImage::Mirror

wxImage Mirror(bool horizontally = true) const

Returns a mirrored copy of the image. The parameter horizontally indicates the orientation.

wxImage::Replace

void Replace(unsigned char r1, unsigned char g1, unsigned char b1, unsigned char r2, unsigned char g2, unsigned char b2)

Replaces the colour specified by r1,g1,b1 by the colour r2,g2,b2.

wxImage::Rescale

wxImage & Rescale(int width, int 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.

See also

Scale

wxImage::Resize

wxImage & Resize(const wxSize& size, const wxPoint& pos, int red = -1, int green = -1, 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 size and background colour at the position pos relative to the upper left of the new image. If 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.

See also

Size

wxImage::Rotate

wxImage Rotate(double angle, const wxPoint& rotationCentre, bool interpolating = true, wxPoint* offsetAfterRotation = NULL)

Rotates the image about the given point, by angle radians. Passing true to interpolating results in better image quality, but is slower. If the image has a mask, then the mask colour is used for the uncovered pixels in the rotated image background. Else, black (rgb 0, 0, 0) will be used.

Returns the rotated image, leaving this image intact.

wxImage::Rotate90

wxImage Rotate90(bool clockwise = true) const

Returns a copy of the image rotated 90 degrees in the direction indicated by clockwise.

wxImage::SaveFile

bool SaveFile(const wxString& name, int type) const

bool SaveFile(const wxString& name, const wxString& mimetype) const

Saves an image in the named file.

bool SaveFile(const wxString& name) const

Saves an image in the named file. File type is determined from the extension of the file name. Note that this function may fail if the extension is not recognized! You can use one of the forms above to save images to files with non-standard extensions.

bool SaveFile(wxOutputStream& stream, int type) const

bool SaveFile(wxOutputStream& stream, const wxString& mimetype) const

Saves an image in the given stream.

Parameters

name: Name of the file to save the image to.

stream: Opened output stream to save the image to.

type

Currently these types can be used:

wxBITMAP_TYPE_BMP Save a BMP image file.

wxBITMAP_TYPE_JPEG Save a JPEG image file.

wxBITMAP_TYPE_PNG Save a PNG image file.

wxBITMAP_TYPE_PCX Save a PCX image file (tries to save as 8-bit if possible, falls back to 24-bit otherwise).

wxBITMAP_TYPE_PNM Save a PNM image file (as raw RGB always).

wxBITMAP_TYPE_TIFF Save a TIFF image file.

wxBITMAP_TYPE_XPM Save a XPM image file.

wxBITMAP_TYPE_ICO Save a Windows icon file (ICO) (the size may be up to 255 wide by 127 high. A single image is saved in 8 colors at the size supplied).

wxBITMAP_TYPE_CUR Save a Windows cursor file (CUR).

mimetype: MIME type.

Return value

true if the operation succeeded, false otherwise.

Remarks

Depending on how wxWidgets has been configured, not all formats may be available.

Note: you can use GetOptionInt to set the hotspot before saving an image into a cursor file (default hotspot is in the centre of the image):

    image.SetOption(wxIMAGE_OPTION_CUR_HOTSPOT_X, hotspotX);
    image.SetOption(wxIMAGE_OPTION_CUR_HOTSPOT_Y, hotspotY);

See also

wxImage::LoadFile

wxPython での注意点: In place of a single overloaded method name, wxPython implements the following methods:

2cm

SaveFile(filename, type) Saves the image using the given type to the named file

SaveMimeFile(filename, mimetype) Saves the image using the given mimetype to the named file

wxPerl での注意点: Methods supported by wxPerl are:

bitmap->SaveFile( name, type )
bitmap->SaveFile( name, mimetype )

wxImage::Scale

wxImage Scale(int width, int height) const

Returns a scaled version of the image. This is also useful for scaling bitmaps in general as the only other way to scale bitmaps 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.

Example:

    // get the bitmap from somewhere
    wxBitmap bmp = ...;

    // rescale it to have size of 32*32
    if ( bmp.GetWidth() != 32 || bmp.GetHeight() != 32 )
    {
        wxImage image = bmp.ConvertToImage();
        bmp = wxBitmap(image.Scale(32, 32));

        // another possibility:
        image.Rescale(32, 32);
        bmp = image;
    }

See also

Rescale

wxImage::Size

wxImage Size(const wxSize& size, const wxPoint& pos, int red = -1, int green = -1, int blue = -1) const

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 size and background colour at the position pos relative to the upper left of the new image. If 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.

See also

Resize

wxImage::SetAlpha

void SetAlpha(unsigned char * alpha = NULL,bool static_data = FALSE)

This function is similar to SetData and has similar restrictions. The pointer passed to it may however be 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 NULL, it must have one byte for each image pixel and be allocated with malloc(). wxImage takes ownership of the pointer and will free it unless static_data parameter is set.to TRUE- in this case the caller should do it.

void SetAlpha(int x, int y, unsigned char alpha)

Sets the alpha value for the given pixel. This function should only be called if the image has alpha channel data, use HasAlpha to check for this.

wxImage::SetData

void SetData(unsigned char* data)

Sets the image data without performing checks. The data given must have the size (width*height*3) or results will be unexpected. Don't use this method if you aren't sure you know what you are doing.

The data must have been allocated with malloc(), NOT with operator new.

After this call the pointer to the data is owned by the wxImage object, that will be responsible for deleting it. Do not pass to this function a pointer obtained through wxImage::GetData.

wxImage::SetMask

void SetMask(bool hasMask = true)

Specifies whether there is a mask or not. The area of the mask is determined by the current mask colour.

wxImage::SetMaskColour

void SetMaskColour(unsigned char red, unsigned char green, unsigned char blue)

Sets the mask colour for this image (and tells the image to use the mask).

wxImage::SetMaskFromImage

bool SetMaskFromImage(const wxImage& mask, unsigned char mr, unsigned char mg, unsigned char mb)

Parameters

mask: The mask image to extract mask shape from. Must have same dimensions as the image.

mr,mg,mb: RGB value of pixels in mask that will be used to create the mask.

Sets image's mask so that the pixels that have RGB value of mr,mg,mb in 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 in mask has given RGB value.

Return value

Returns false if mask does not have same dimensions as the image or if there is no unused colour left. Returns true if the mask was successfully applied.

Notes

Note that this method involves computing the histogram, which is computationally intensive operation.

wxImage::SetOption

void SetOption(const wxString& name, const wxString& value)

void SetOption(const wxString& name, int value)

Sets a user-defined option. The function is case-insensitive to name.

For example, when saving as a JPEG file, the option quality is used, which is a number between 0 and 100 (0 is terrible, 100 is very good).

wxImage::SetPalette

void SetPalette(const wxPalette& palette)

Associates a palette with the image. The palette may be used when converting wxImage to wxBitmap (MSW only at present) or in file save operations (none as yet).

wxImage::SetRGB

void SetRGB(int x, int y, unsigned char red, unsigned char green, unsigned char blue)

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 using the GetData method.

wxImage::SetRGB

void SetRGB(wxRect & rect, unsigned char red, unsigned char green, 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.

wxImage::operator

wxImage& operator (const wxImage& image)

Assignment operator. This operator does not copy any data, but instead passes a pointer to the data in image and increments a reference counter. It is a fast operation.

Parameters

image: Image to assign.

Return value

Returns 'this' object.

wxImage::operator

bool operator (const wxImage& image) const

Equality operator. This operator tests whether the internal data pointers are equal (a fast test).

Parameters

image: Image to compare with 'this'

Return value

Returns true if the images were effectively equal, false otherwise.

wxImage::operator $\!=$

bool operator $\!=$ (const wxImage& image) const

Inequality operator. This operator tests whether the internal data pointers are unequal (a fast test).

Parameters

image: Image to compare with 'this'

Return value

Returns true if the images were unequal, false otherwise.

ymasuda 平成17年11月19日

wxBMPHandler	For loading and saving, always installed.
wxPNGHandler	For loading (including alpha support) and saving.
wxJPEGHandler	For loading and saving.
wxGIFHandler	Only for loading, due to legal issues.
wxPCXHandler	For loading and saving (see below).
wxPNMHandler	For loading and saving (see below).
wxTIFFHandler	For loading and saving.
wxIFFHandler	For loading only.
wxXPMHandler	For loading and saving.
wxICOHandler	For loading and saving.
wxCURHandler	For loading and saving.
wxANIHandler	For loading only.

wxBITMAP_TYPE_BMP	Load a Windows bitmap file.
wxBITMAP_TYPE_GIF	Load a GIF bitmap file.
wxBITMAP_TYPE_JPEG	Load a JPEG bitmap file.
wxBITMAP_TYPE_PNG	Load a PNG bitmap file.
wxBITMAP_TYPE_PCX	Load a PCX bitmap file.
wxBITMAP_TYPE_PNM	Load a PNM bitmap file.
wxBITMAP_TYPE_TIF	Load a TIFF bitmap file.
wxBITMAP_TYPE_XPM	Load a XPM bitmap file.
wxBITMAP_TYPE_ICO	Load a Windows icon file (ICO).
wxBITMAP_TYPE_CUR	Load a Windows cursor file (CUR).
wxBITMAP_TYPE_ANI	Load a Windows animated cursor file (ANI).
wxBITMAP_TYPE_ANY	Will try to autodetect the format.

wxImage(name, flag)	Loads an image from a file
wxNullImage()	Create a null image (has no size or image data)
wxEmptyImage(width, height)	Creates an empty image of the given size
wxImageFromMime(name, mimetype	Creates an image from the given file of the given mimetype
wxImageFromBitmap(bitmap)	Creates an image from a platform-dependent bitmap

wxIMAGE_OPTION_PNG_FORMAT	Format for saving a PNG file.
wxIMAGE_OPTION_PNG_BITDEPTH	Bit depth for every channel (R/G/B/A).

wxPNG_TYPE_COLOUR	Stores RGB image.
wxPNG_TYPE_GREY	Stores grey image, converts from RGB.
wxPNG_TYPE_GREY_RED	Stores grey image, uses red value as grey.

wxBITMAP_TYPE_BMP	Load a Windows image file.
wxBITMAP_TYPE_GIF	Load a GIF image file.
wxBITMAP_TYPE_JPEG	Load a JPEG image file.
wxBITMAP_TYPE_PCX	Load a PCX image file.
wxBITMAP_TYPE_PNG	Load a PNG image file.
wxBITMAP_TYPE_PNM	Load a PNM image file.
wxBITMAP_TYPE_TIF	Load a TIFF image file.
wxBITMAP_TYPE_XPM	Load a XPM image file.
wxBITMAP_TYPE_ICO	Load a Windows icon file (ICO).
wxBITMAP_TYPE_CUR	Load a Windows cursor file (CUR).
wxBITMAP_TYPE_ANI	Load a Windows animated cursor file (ANI).
wxBITMAP_TYPE_ANY	Will try to autodetect the format.

LoadFile(filename, type)	Loads an image of the given type from a file
LoadMimeFile(filename, mimetype)	Loads an image of the given mimetype from a file

wxBITMAP_TYPE_BMP	Save a BMP image file.
wxBITMAP_TYPE_JPEG	Save a JPEG image file.
wxBITMAP_TYPE_PNG	Save a PNG image file.
wxBITMAP_TYPE_PCX	Save a PCX image file (tries to save as 8-bit if possible, falls back to 24-bit otherwise).
wxBITMAP_TYPE_PNM	Save a PNM image file (as raw RGB always).
wxBITMAP_TYPE_TIFF	Save a TIFF image file.
wxBITMAP_TYPE_XPM	Save a XPM image file.
wxBITMAP_TYPE_ICO	Save a Windows icon file (ICO) (the size may be up to 255 wide by 127 high. A single image is saved in 8 colors at the size supplied).
wxBITMAP_TYPE_CUR	Save a Windows cursor file (CUR).

SaveFile(filename, type)	Saves the image using the given type to the named file
SaveMimeFile(filename, mimetype)	Saves the image using the given mimetype to the named file