add overloads of ctors and Create() functions taking wxSize; document the various...
[wxWidgets.git] / interface / wx / image.h
1 /////////////////////////////////////////////////////////////////////////////
2 // Name: image.h
3 // Purpose: interface of wxImageHandler and wxImage
4 // Author: wxWidgets team
5 // RCS-ID: $Id$
6 // Licence: wxWindows license
7 /////////////////////////////////////////////////////////////////////////////
8
9 /**
10 Possible values for the image resolution option.
11
12 @see wxImage::GetOptionInt().
13 */
14 enum wxImageResolution
15 {
16 /// Resolution not specified.
17 wxIMAGE_RESOLUTION_NONE = 0,
18
19 /// Resolution specified in inches.
20 wxIMAGE_RESOLUTION_INCHES = 1,
21
22 /// Resolution specified in centimetres.
23 wxIMAGE_RESOLUTION_CM = 2
24 };
25
26 /**
27 Possible values for PNG image type option.
28
29 @see wxImage::GetOptionInt().
30 */
31 enum wxImagePNGType
32 {
33 wxPNG_TYPE_COLOUR = 0, ///< Colour PNG image.
34 wxPNG_TYPE_GREY = 2, ///< Greyscale PNG image converted from RGB.
35 wxPNG_TYPE_GREY_RED = 3 ///< Greyscale PNG image using red as grey.
36 };
37
38 /**
39 @class wxImageHandler
40
41 This is the base class for implementing image file loading/saving, and
42 image creation from data.
43 It is used within wxImage and is not normally seen by the application.
44
45 If you wish to extend the capabilities of wxImage, derive a class from
46 wxImageHandler and add the handler using wxImage::AddHandler in your
47 application initialization.
48
49 Note that all wxImageHandlers provided by wxWidgets are part of
50 the @ref page_libs_wxcore library.
51 For details about the default handlers, please see the section
52 @ref image_handlers in the wxImage class documentation.
53
54
55 @section imagehandler_note Note (Legal Issue)
56
57 This software is based in part on the work of the Independent JPEG Group.
58 (Applies when wxWidgets is linked with JPEG support.
59 wxJPEGHandler uses libjpeg created by IJG.)
60
61
62 @stdobjects
63 ::wxNullImage
64
65 @library{wxcore}
66 @category{gdi}
67
68 @see wxImage, wxInitAllImageHandlers()
69 */
70 class wxImageHandler : public wxObject
71 {
72 public:
73 /**
74 Default constructor.
75
76 In your own default constructor, initialise the members
77 m_name, m_extension and m_type.
78 */
79 wxImageHandler();
80
81 /**
82 Destroys the wxImageHandler object.
83 */
84 virtual ~wxImageHandler();
85
86 /**
87 Gets the preferred file extension associated with this handler.
88
89 @see GetAltExtensions()
90 */
91 const wxString& GetExtension() const;
92
93 /**
94 Returns the other file extensions associated with this handler.
95
96 The preferred extension for this handler is returned by GetExtension().
97
98 @since 2.9.0
99 */
100 const wxArrayString& GetAltExtensions() const;
101
102 /**
103 If the image file contains more than one image and the image handler is capable
104 of retrieving these individually, this function will return the number of
105 available images.
106
107 @param stream
108 Opened input stream for reading image data.
109 Currently, the stream must support seeking.
110
111 @return Number of available images. For most image handlers, this is 1
112 (exceptions are TIFF and ICO formats).
113 */
114 virtual int GetImageCount(wxInputStream& stream);
115
116 /**
117 Gets the MIME type associated with this handler.
118 */
119 const wxString& GetMimeType() const;
120
121 /**
122 Gets the name of this handler.
123 */
124 const wxString& GetName() const;
125
126 /**
127 Gets the image type associated with this handler.
128 */
129 wxBitmapType GetType() const;
130
131 /**
132 Loads a image from a stream, putting the resulting data into @a image.
133
134 If the image file contains more than one image and the image handler is
135 capable of retrieving these individually, @a index indicates which image
136 to read from the stream.
137
138 @param image
139 The image object which is to be affected by this operation.
140 @param stream
141 Opened input stream for reading image data.
142 @param verbose
143 If set to @true, errors reported by the image handler will produce
144 wxLogMessages.
145 @param index
146 The index of the image in the file (starting from zero).
147
148 @return @true if the operation succeeded, @false otherwise.
149
150 @see wxImage::LoadFile, wxImage::SaveFile, SaveFile()
151 */
152 virtual bool LoadFile(wxImage* image, wxInputStream& stream,
153 bool verbose = true, int index = -1);
154
155 /**
156 Saves a image in the output stream.
157
158 @param image
159 The image object which is to be affected by this operation.
160 @param stream
161 Opened output stream for writing the data.
162 @param verbose
163 If set to @true, errors reported by the image handler will produce
164 wxLogMessages.
165
166 @return @true if the operation succeeded, @false otherwise.
167
168 @see wxImage::LoadFile, wxImage::SaveFile, LoadFile()
169 */
170 virtual bool SaveFile(wxImage* image, wxOutputStream& stream,
171 bool verbose = true);
172
173 /**
174 Sets the preferred file extension associated with this handler.
175
176 @param extension
177 File extension without leading dot.
178
179 @see SetAltExtensions()
180 */
181 void SetExtension(const wxString& extension);
182
183 /**
184 Sets the alternative file extensions associated with this handler.
185
186 @param extensions
187 Array of file extensions.
188
189 @see SetExtension()
190
191 @since 2.9.0
192 */
193 void SetAltExtensions(const wxArrayString& extensions);
194
195 /**
196 Sets the handler MIME type.
197
198 @param mimetype
199 Handler MIME type.
200 */
201 void SetMimeType(const wxString& mimetype);
202
203 /**
204 Sets the handler name.
205
206 @param name
207 Handler name.
208 */
209 void SetName(const wxString& name);
210 };
211
212
213 /**
214 Constant used to indicate the alpha value conventionally defined as
215 the complete transparency.
216 */
217 const unsigned char wxIMAGE_ALPHA_TRANSPARENT = 0;
218
219 /**
220 Constant used to indicate the alpha value conventionally defined as
221 the complete opacity.
222 */
223 const unsigned char wxIMAGE_ALPHA_OPAQUE = 0xff;
224
225 /**
226 @class wxImage
227
228 This class encapsulates a platform-independent image.
229
230 An image can be created from data, or using wxBitmap::ConvertToImage.
231 An image can be loaded from a file in a variety of formats, and is extensible
232 to new formats via image format handlers. Functions are available to set and
233 get image bits, so it can be used for basic image manipulation.
234
235 A wxImage cannot (currently) be drawn directly to a wxDC.
236 Instead, a platform-specific wxBitmap object must be created from it using
237 the wxBitmap::wxBitmap(wxImage,int depth) constructor.
238 This bitmap can then be drawn in a device context, using wxDC::DrawBitmap.
239
240 One colour value of the image may be used as a mask colour which will lead to
241 the automatic creation of a wxMask object associated to the bitmap object.
242
243
244 @section image_alpha Alpha channel support
245
246 Starting from wxWidgets 2.5.0 wxImage supports alpha channel data, that is
247 in addition to a byte for the red, green and blue colour components for each
248 pixel it also stores a byte representing the pixel opacity.
249
250 An alpha value of 0 corresponds to a transparent pixel (null opacity) while
251 a value of 255 means that the pixel is 100% opaque.
252 The constants ::wxIMAGE_ALPHA_TRANSPARENT and ::wxIMAGE_ALPHA_OPAQUE can be
253 used to indicate those values in a more readable form.
254
255 Unlike RGB data, not all images have an alpha channel and before using
256 wxImage::GetAlpha you should check if this image contains an alpha channel
257 with wxImage::HasAlpha. Note that currently only the PNG format has full
258 alpha channel support so only the images loaded from PNG files can have
259 alpha and, if you initialize the image alpha channel yourself using
260 wxImage::SetAlpha, you should save it in PNG format to avoid losing it.
261
262
263 @section image_handlers Available image handlers
264
265 The following image handlers are available.
266 wxBMPHandler is always installed by default.
267 To use other image formats, install the appropriate handler with
268 wxImage::AddHandler or call ::wxInitAllImageHandlers().
269
270 - wxBMPHandler: For loading and saving, always installed.
271 - wxPNGHandler: For loading (including alpha support) and saving.
272 - wxJPEGHandler: For loading and saving.
273 - wxGIFHandler: Only for loading, due to legal issues.
274 - wxPCXHandler: For loading and saving (see below).
275 - wxPNMHandler: For loading and saving (see below).
276 - wxTIFFHandler: For loading and saving.
277 - wxTGAHandler: For loading only.
278 - wxIFFHandler: For loading only.
279 - wxXPMHandler: For loading and saving.
280 - wxICOHandler: For loading and saving.
281 - wxCURHandler: For loading and saving.
282 - wxANIHandler: For loading only.
283
284 When saving in PCX format, wxPCXHandler will count the number of different
285 colours in the image; if there are 256 or less colours, it will save as 8 bit,
286 else it will save as 24 bit.
287
288 Loading PNMs only works for ASCII or raw RGB images.
289 When saving in PNM format, wxPNMHandler will always save as raw RGB.
290
291
292 @library{wxcore}
293 @category{gdi}
294
295 @stdobjects
296 ::wxNullImage
297
298 @see wxBitmap, wxInitAllImageHandlers(), wxPixelData
299 */
300 class wxImage : public wxObject
301 {
302 public:
303 /**
304 A simple class which stores red, green and blue values as 8 bit unsigned integers
305 in the range of 0-255.
306 */
307 class RGBValue
308 {
309 public:
310 /**
311 Constructor for RGBValue, an object that contains values for red, green
312 and blue which represent the value of a color.
313
314 It is used by wxImage::HSVtoRGB and wxImage::RGBtoHSV, which convert
315 between HSV color space and RGB color space.
316 */
317 RGBValue(unsigned char r=0, unsigned char g=0, unsigned char b=0);
318 };
319
320 /**
321 A simple class which stores hue, saturation and value as doubles in the range 0.0-1.0.
322 */
323 class HSVValue
324 {
325 public:
326 /**
327 Constructor for HSVValue, an object that contains values for hue, saturation
328 and value which represent the value of a color.
329
330 It is used by wxImage::HSVtoRGB() and wxImage::RGBtoHSV(), which convert
331 between HSV color space and RGB color space.
332 */
333 HSVValue(double h=0.0, double s=0.0, double v=0.0);
334 };
335
336 /**
337 Creates an empty wxImage object without an alpha channel.
338 */
339 wxImage();
340
341 /**
342 Creates an image with the given size and clears it if requested.
343
344 Does not create an alpha channel.
345
346 @param width
347 Specifies the width of the image.
348 @param height
349 Specifies the height of the image.
350 @param clear
351 If @true, initialize the image to black.
352 */
353 wxImage(int width, int height, bool clear = true);
354
355 /**
356 @overload
357 */
358 wxImage(const wxSize& sz, bool clear = true);
359
360 /**
361 Creates an image from data in memory. If @a static_data is @false
362 then the wxImage will take ownership of the data and free it
363 afterwards. For this, it has to be allocated with @e malloc.
364
365 @param width
366 Specifies the width of the image.
367 @param height
368 Specifies the height of the image.
369 @param data
370 A pointer to RGB data
371 @param static_data
372 Indicates if the data should be free'd after use
373
374 */
375 wxImage(int width, int height, unsigned char* data, bool static_data = false);
376
377 /**
378 @overload
379 */
380 wxImage(const wxSize& sz, unsigned char* data, bool static_data = false);
381
382 /**
383 Creates an image from data in memory. If @a static_data is @false
384 then the wxImage will take ownership of the data and free it
385 afterwards. For this, it has to be allocated with @e malloc.
386
387 @param width
388 Specifies the width of the image.
389 @param height
390 Specifies the height of the image.
391 @param data
392 A pointer to RGB data
393 @param alpha
394 A pointer to alpha-channel data
395 @param static_data
396 Indicates if the data should be free'd after use
397
398 */
399 wxImage(int width, int height, unsigned char* data, unsigned char* alpha,
400 bool static_data = false );
401
402 /**
403 @overload
404 */
405 wxImage(const wxSize& sz, unsigned char* data, unsigned char* data, unsigned char* alpha,
406 bool static_data = false);
407
408 /**
409 Creates an image from XPM data.
410
411 @param xpmData
412 A pointer to XPM image data.
413 */
414 wxImage(const char* const* xpmData);
415
416 /**
417 Creates an image from a file.
418
419 @param name
420 Name of the file from which to load the image.
421 @param type
422 May be one of the following:
423 @li wxBITMAP_TYPE_BMP: Load a Windows bitmap file.
424 @li wxBITMAP_TYPE_GIF: Load a GIF bitmap file.
425 @li wxBITMAP_TYPE_JPEG: Load a JPEG bitmap file.
426 @li wxBITMAP_TYPE_PNG: Load a PNG bitmap file.
427 @li wxBITMAP_TYPE_PCX: Load a PCX bitmap file.
428 @li wxBITMAP_TYPE_PNM: Load a PNM bitmap file.
429 @li wxBITMAP_TYPE_TIF: Load a TIFF bitmap file.
430 @li wxBITMAP_TYPE_TGA: Load a TGA bitmap file.
431 @li wxBITMAP_TYPE_XPM: Load a XPM bitmap file.
432 @li wxBITMAP_TYPE_ICO: Load a Windows icon file (ICO).
433 @li wxBITMAP_TYPE_CUR: Load a Windows cursor file (CUR).
434 @li wxBITMAP_TYPE_ANI: Load a Windows animated cursor file (ANI).
435 @li wxBITMAP_TYPE_ANY: Will try to autodetect the format.
436 @param index
437 Index of the image to load in the case that the image file contains
438 multiple images. This is only used by GIF, ICO and TIFF handlers.
439 The default value (-1) means "choose the default image" and is
440 interpreted as the first image (index=0) by the GIF and TIFF handler
441 and as the largest and most colourful one by the ICO handler.
442
443 @remarks Depending on how wxWidgets has been configured and by which
444 handlers have been loaded, not all formats may be available.
445 Any handler other than BMP must be previously initialized with
446 wxImage::AddHandler or wxInitAllImageHandlers.
447
448 @note
449 You can use GetOptionInt() to get the hotspot when loading cursor files:
450 @code
451 int hotspot_x = image.GetOptionInt(wxIMAGE_OPTION_CUR_HOTSPOT_X);
452 int hotspot_y = image.GetOptionInt(wxIMAGE_OPTION_CUR_HOTSPOT_Y);
453 @endcode
454
455 @see LoadFile()
456 */
457 wxImage(const wxString& name, wxBitmapType type = wxBITMAP_TYPE_ANY, int index = -1);
458
459 /**
460 Creates an image from a file using MIME-types to specify the type.
461
462 @param name
463 Name of the file from which to load the image.
464 @param mimetype
465 MIME type string (for example 'image/jpeg')
466 @param index
467 See description in wxImage(const wxString&, wxBitmapType, int) overload.
468 */
469 wxImage(const wxString& name, const wxString& mimetype, int index = -1);
470
471 /**
472 Creates an image from a stream.
473
474 @param stream
475 Opened input stream from which to load the image. Currently,
476 the stream must support seeking.
477 @param type
478 See description in wxImage(const wxString&, wxBitmapType, int) overload.
479 @param index
480 See description in wxImage(const wxString&, wxBitmapType, int) overload.
481 */
482 wxImage(wxInputStream& stream, wxBitmapType type = wxBITMAP_TYPE_ANY, int index = -1);
483
484 /**
485 Creates an image from a stream using MIME-types to specify the type.
486
487 @param stream
488 Opened input stream from which to load the image. Currently,
489 the stream must support seeking.
490 @param mimetype
491 MIME type string (for example 'image/jpeg')
492 @param index
493 See description in wxImage(const wxString&, wxBitmapType, int) overload.
494 */
495 wxImage(wxInputStream& stream, const wxString& mimetype, int index = -1);
496
497 /**
498 Destructor.
499
500 See @ref overview_refcount_destruct "reference-counted object destruction"
501 for more info.
502 */
503 virtual ~wxImage();
504
505
506
507 /**
508 @name Image creation, initialization and deletion functions
509 */
510 //@{
511
512 /**
513 Returns an identical copy of this image.
514 */
515 wxImage Copy() const;
516
517 /**
518 Creates a fresh image.
519 See wxImage::wxImage(int,int,bool) for more info.
520
521 @return @true if the call succeeded, @false otherwise.
522 */
523 bool Create(int width, int height, bool clear = true);
524
525 /**
526 @overload
527 */
528 bool Create( const wxSize& sz, bool clear = true );
529
530 /**
531 Creates a fresh image.
532 See wxImage::wxImage(int,int,unsigned char*,bool) for more info.
533
534 @return @true if the call succeeded, @false otherwise.
535 */
536 bool Create( int width, int height, unsigned char* data, bool static_data = false );
537
538 /**
539 @overload
540 */
541 bool Create( const wxSize& sz, unsigned char* data, bool static_data = false );
542
543 /**
544 Creates a fresh image.
545 See wxImage::wxImage(int,int,unsigned char*,unsigned char*,bool) for more info.
546
547 @return @true if the call succeeded, @false otherwise.
548 */
549 bool Create( int width, int height, unsigned char* data, unsigned char* alpha, bool static_data = false );
550
551 /**
552 @overload
553 */
554 bool Create( const wxSize& sz, unsigned char* data, unsigned char* alpha, bool static_data = false );
555
556 /**
557 Initialize the image data with zeroes (the default) or with the
558 byte value given as @a value.
559
560 @since 2.9.0
561 */
562 void Clear(unsigned char value = 0);
563
564 /**
565 Destroys the image data.
566 */
567 void Destroy();
568
569 /**
570 Initializes the image alpha channel data.
571
572 It is an error to call it if the image already has alpha data.
573 If it doesn't, alpha data will be by default initialized to all pixels
574 being fully opaque. But if the image has a mask colour, all mask pixels
575 will be completely transparent.
576 */
577 void InitAlpha();
578
579 //@}
580
581
582 /**
583 @name Image manipulation functions
584 */
585 //@{
586
587 /**
588 Blurs the image in both horizontal and vertical directions by the
589 specified pixel @a blurRadius. This should not be used when using
590 a single mask colour for transparency.
591
592 @see BlurHorizontal(), BlurVertical()
593 */
594 wxImage Blur(int blurRadius) const;
595
596 /**
597 Blurs the image in the horizontal direction only. This should not be used
598 when using a single mask colour for transparency.
599
600 @see Blur(), BlurVertical()
601 */
602 wxImage BlurHorizontal(int blurRadius) const;
603
604 /**
605 Blurs the image in the vertical direction only. This should not be used
606 when using a single mask colour for transparency.
607
608 @see Blur(), BlurHorizontal()
609 */
610 wxImage BlurVertical(int blurRadius) const;
611
612 /**
613 Returns a mirrored copy of the image.
614 The parameter @a horizontally indicates the orientation.
615 */
616 wxImage Mirror(bool horizontally = true) const;
617
618 /**
619 Copy the data of the given @a image to the specified position in this image.
620 */
621 void Paste(const wxImage& image, int x, int y);
622
623 /**
624 Replaces the colour specified by @e r1,g1,b1 by the colour @e r2,g2,b2.
625 */
626 void Replace(unsigned char r1, unsigned char g1,
627 unsigned char b1, unsigned char r2,
628 unsigned char g2, unsigned char b2);
629
630 /**
631 Changes the size of the image in-place by scaling it: after a call to this
632 function,the image will have the given width and height.
633
634 For a description of the @a quality parameter, see the Scale() function.
635 Returns the (modified) image itself.
636
637 @see Scale()
638 */
639 wxImage& Rescale(int width, int height,
640 int quality = wxIMAGE_QUALITY_NORMAL);
641
642 /**
643 Changes the size of the image in-place without scaling it by adding either a
644 border with the given colour or cropping as necessary.
645
646 The image is pasted into a new image with the given @a size and background
647 colour at the position @a pos relative to the upper left of the new image.
648
649 If @a red = green = blue = -1 then use either the current mask colour
650 if set or find, use, and set a suitable mask colour for any newly exposed
651 areas.
652
653 @return The (modified) image itself.
654
655 @see Size()
656 */
657 wxImage& Resize(const wxSize& size, const wxPoint& pos, int red = -1,
658 int green = -1, int blue = -1);
659
660 /**
661 Rotates the image about the given point, by @a angle radians.
662
663 Passing @true to @a interpolating results in better image quality, but is slower.
664
665 If the image has a mask, then the mask colour is used for the uncovered
666 pixels in the rotated image background. Else, black (rgb 0, 0, 0) will be used.
667
668 Returns the rotated image, leaving this image intact.
669 */
670 wxImage Rotate(double angle, const wxPoint& rotationCentre,
671 bool interpolating = true,
672 wxPoint* offsetAfterRotation = NULL) const;
673
674 /**
675 Returns a copy of the image rotated 90 degrees in the direction
676 indicated by @a clockwise.
677 */
678 wxImage Rotate90(bool clockwise = true) const;
679
680 /**
681 Rotates the hue of each pixel in the image by @e angle, which is a double in
682 the range of -1.0 to +1.0, where -1.0 corresponds to -360 degrees and +1.0
683 corresponds to +360 degrees.
684 */
685 void RotateHue(double angle);
686
687 /**
688 Returns a scaled version of the image.
689
690 This is also useful for scaling bitmaps in general as the only other way
691 to scale bitmaps is to blit a wxMemoryDC into another wxMemoryDC.
692
693 The parameter @a quality determines what method to use for resampling the image.
694 Can be one of the following:
695 - wxIMAGE_QUALITY_NORMAL: Uses the normal default scaling method of pixel
696 replication
697 - wxIMAGE_QUALITY_HIGH: Uses bicubic and box averaging resampling methods
698 for upsampling and downsampling respectively
699
700 It should be noted that although using @c wxIMAGE_QUALITY_HIGH produces much nicer
701 looking results it is a slower method. Downsampling will use the box averaging
702 method which seems to operate very fast. If you are upsampling larger images using
703 this method you will most likely notice that it is a bit slower and in extreme
704 cases it will be quite substantially slower as the bicubic algorithm has to process a
705 lot of data.
706
707 It should also be noted that the high quality scaling may not work as expected
708 when using a single mask colour for transparency, as the scaling will blur the
709 image and will therefore remove the mask partially. Using the alpha channel
710 will work.
711
712 Example:
713 @code
714 // get the bitmap from somewhere
715 wxBitmap bmp = ...;
716
717 // rescale it to have size of 32*32
718 if ( bmp.GetWidth() != 32 || bmp.GetHeight() != 32 )
719 {
720 wxImage image = bmp.ConvertToImage();
721 bmp = wxBitmap(image.Scale(32, 32));
722
723 // another possibility:
724 image.Rescale(32, 32);
725 bmp = image;
726 }
727 @endcode
728
729 @see Rescale()
730 */
731 wxImage Scale(int width, int height,
732 int quality = wxIMAGE_QUALITY_NORMAL) const;
733
734 /**
735 Returns a resized version of this image without scaling it by adding either a
736 border with the given colour or cropping as necessary.
737
738 The image is pasted into a new image with the given @a size and background
739 colour at the position @a pos relative to the upper left of the new image.
740
741 If @a red = green = blue = -1 then the areas of the larger image not covered
742 by this image are made transparent by filling them with the image mask colour
743 (which will be allocated automatically if it isn't currently set).
744
745 Otherwise, the areas will be filled with the colour with the specified RGB components.
746
747 @see Resize()
748 */
749 wxImage Size(const wxSize& size, const wxPoint& pos, int red = -1,
750 int green = -1, int blue = -1) const;
751
752 //@}
753
754
755 /**
756 @name Conversion functions
757 */
758 //@{
759
760 /**
761 If the image has alpha channel, this method converts it to mask.
762
763 If the image has an alpha channel, all pixels with alpha value less
764 than @a threshold are replaced with the mask colour and the alpha
765 channel is removed. Otherwise nothing is done.
766
767 The mask colour is chosen automatically using
768 FindFirstUnusedColour() by this function, see the overload below if you
769 this is not appropriate.
770
771 @return @false if FindFirstUnusedColour returns @false, @true otherwise.
772 */
773 bool ConvertAlphaToMask(unsigned char threshold = wxIMAGE_ALPHA_THRESHOLD);
774
775 /**
776 If the image has alpha channel, this method converts it to mask using
777 the specified colour as the mask colour.
778
779 If the image has an alpha channel, all pixels with alpha value less
780 than @a threshold are replaced with the mask colour and the alpha
781 channel is removed. Otherwise nothing is done.
782
783 @since 2.9.0
784
785 @param mr
786 The red component of the mask colour.
787 @param mg
788 The green component of the mask colour.
789 @param mb
790 The blue component of the mask colour.
791 @param threshold
792 Pixels with alpha channel values below the given threshold are
793 considered to be transparent, i.e. the corresponding mask pixels
794 are set. Pixels with the alpha values above the threshold are
795 considered to be opaque.
796
797 */
798 void ConvertAlphaToMask(unsigned char mr, unsigned char mg, unsigned char mb,
799 unsigned char threshold = wxIMAGE_ALPHA_THRESHOLD);
800
801 /**
802 Returns a greyscale version of the image.
803
804 The returned image uses the luminance component of the original to
805 calculate the greyscale. Defaults to using the standard ITU-T BT.601
806 when converting to YUV, where every pixel equals
807 (R * @a lr) + (G * @a lg) + (B * @a lb).
808 */
809 wxImage ConvertToGreyscale(double lr = 0.299, double lg = 0.587, double lb = 1.114) const;
810
811 /**
812 Returns monochromatic version of the image.
813
814 The returned image has white colour where the original has @e (r,g,b)
815 colour and black colour everywhere else.
816 */
817 wxImage ConvertToMono(unsigned char r, unsigned char g, unsigned char b) const;
818
819 //@}
820
821
822 /**
823 @name Miscellaneous functions
824 */
825 //@{
826
827 /**
828 Computes the histogram of the image. @a histogram is a reference to
829 wxImageHistogram object. wxImageHistogram is a specialization of
830 wxHashMap "template" and is defined as follows:
831
832 @code
833 class WXDLLEXPORT wxImageHistogramEntry
834 {
835 public:
836 wxImageHistogramEntry() : index(0), value(0) {}
837 unsigned long index;
838 unsigned long value;
839 };
840
841 WX_DECLARE_EXPORTED_HASH_MAP(unsigned long, wxImageHistogramEntry,
842 wxIntegerHash, wxIntegerEqual,
843 wxImageHistogram);
844 @endcode
845
846 @return Returns number of colours in the histogram.
847 */
848 unsigned long ComputeHistogram(wxImageHistogram& histogram) const;
849
850 /**
851 Finds the first colour that is never used in the image.
852 The search begins at given initial colour and continues by increasing
853 R, G and B components (in this order) by 1 until an unused colour is
854 found or the colour space exhausted.
855
856 The parameters @a r, @a g, @a b are pointers to variables to save the colour.
857
858 The parameters @a startR, @a startG, @a startB define the initial values
859 of the colour.
860 The returned colour will have RGB values equal to or greater than these.
861
862 @return Returns @false if there is no unused colour left, @true on success.
863
864 @note
865 This method involves computing the histogram, which is a
866 computationally intensive operation.
867 */
868 bool FindFirstUnusedColour(unsigned char* r, unsigned char* g,
869 unsigned char* b, unsigned char startR = 1,
870 unsigned char startG = 0,
871 unsigned char startB = 0) const;
872
873 /**
874 Assignment operator, using @ref overview_refcount "reference counting".
875
876 @param image
877 Image to assign.
878
879 @return Returns 'this' object.
880 */
881 wxImage& operator=(const wxImage& image);
882
883 //@}
884
885
886 /**
887 @name Getters
888 */
889 //@{
890
891 /**
892 Returns pointer to the array storing the alpha values for this image.
893
894 This pointer is @NULL for the images without the alpha channel. If the image
895 does have it, this pointer may be used to directly manipulate the alpha values
896 which are stored as the RGB ones.
897 */
898 unsigned char* GetAlpha() const;
899
900 /**
901 Returns the image data as an array.
902
903 This is most often used when doing direct image manipulation.
904 The return value points to an array of characters in RGBRGBRGB... format
905 in the top-to-bottom, left-to-right order, that is the first RGB triplet
906 corresponds to the pixel first pixel of the first row, the second one ---
907 to the second pixel of the first row and so on until the end of the first
908 row, with second row following after it and so on.
909
910 You should not delete the returned pointer nor pass it to SetData().
911 */
912 unsigned char* GetData() const;
913
914 /**
915 Return alpha value at given pixel location.
916 */
917 unsigned char GetAlpha(int x, int y) const;
918
919 /**
920 Returns the red intensity at the given coordinate.
921 */
922 unsigned char GetRed(int x, int y) const;
923
924 /**
925 Returns the green intensity at the given coordinate.
926 */
927 unsigned char GetGreen(int x, int y) const;
928
929 /**
930 Returns the blue intensity at the given coordinate.
931 */
932 unsigned char GetBlue(int x, int y) const;
933
934 /**
935 Gets the red value of the mask colour.
936 */
937 unsigned char GetMaskRed() const;
938
939 /**
940 Gets the green value of the mask colour.
941 */
942 unsigned char GetMaskGreen() const;
943
944 /**
945 Gets the blue value of the mask colour.
946 */
947 unsigned char GetMaskBlue() const;
948
949 /**
950 Gets the width of the image in pixels.
951
952 @see GetHeight(), GetSize()
953 */
954 int GetWidth() const;
955
956 /**
957 Gets the height of the image in pixels.
958
959 @see GetWidth(), GetSize()
960 */
961 int GetHeight() const;
962
963 /**
964 Returns the size of the image in pixels.
965
966 @since 2.9.0
967
968 @see GetHeight(), GetWidth()
969 */
970 wxSize GetSize() const;
971
972 /**
973 Gets a user-defined string-valued option.
974
975 Currently the only defined string option is
976 @li @c wxIMAGE_OPTION_FILENAME: The name of the file from which the image
977 was loaded.
978
979 @param name
980 The name of the option, case-insensitive.
981 @return
982 The value of the option or an empty string if not found. Use
983 HasOption() if an empty string can be a valid option value.
984
985 @see SetOption(), GetOptionInt(), HasOption()
986 */
987 wxString GetOption(const wxString& name) const;
988
989 /**
990 Gets a user-defined integer-valued option.
991
992 The function is case-insensitive to @a name.
993 If the given option is not present, the function returns 0.
994 Use HasOption() is 0 is a possibly valid value for the option.
995
996 Generic options:
997 @li @c wxIMAGE_OPTION_MAX_WIDTH and @c wxIMAGE_OPTION_MAX_HEIGHT: If either
998 of these options is specified, the loaded image will be scaled down
999 (preserving its aspect ratio) so that its width is less than the
1000 max width given if it is not 0 @em and its height is less than the
1001 max height given if it is not 0. This is typically used for loading
1002 thumbnails and the advantage of using these options compared to
1003 calling Rescale() after loading is that some handlers (only JPEG
1004 one right now) support rescaling the image during loading which is
1005 vastly more efficient than loading the entire huge image and
1006 rescaling it later (if these options are not supported by the
1007 handler, this is still what happens however). These options must be
1008 set before calling LoadFile() to have any effect.
1009
1010 @li @c wxIMAGE_OPTION_QUALITY: JPEG quality used when saving. This is an
1011 integer in 0..100 range with 0 meaning very poor and 100 excellent
1012 (but very badly compressed). This option is currently ignored for
1013 the other formats.
1014
1015 @li @c wxIMAGE_OPTION_RESOLUTIONUNIT: The value of this option determines
1016 whether the resolution of the image is specified in centimetres or
1017 inches, see wxImageResolution enum elements.
1018
1019 @li @c wxIMAGE_OPTION_RESOLUTION, @c wxIMAGE_OPTION_RESOLUTIONX and
1020 @c wxIMAGE_OPTION_RESOLUTIONY: These options define the resolution of
1021 the image in the units corresponding to @c wxIMAGE_OPTION_RESOLUTIONUNIT
1022 options value. The first option can be set before saving the image
1023 to set both horizontal and vertical resolution to the same value.
1024 The X and Y options are set by the image handlers if they support
1025 the image resolution (currently BMP, JPEG and TIFF handlers do) and
1026 the image provides the resolution information and can be queried
1027 after loading the image.
1028
1029 Options specific to wxPNGHandler:
1030 @li @c wxIMAGE_OPTION_PNG_FORMAT: Format for saving a PNG file, see
1031 wxImagePNGType for the supported values.
1032 @li @c wxIMAGE_OPTION_PNG_BITDEPTH: Bit depth for every channel (R/G/B/A).
1033 @li @c wxIMAGE_OPTION_PNG_FILTER: Filter for saving a PNG file, see libpng
1034 (http://www.libpng.org/pub/png/libpng-1.2.5-manual.html) for possible values
1035 (e.g. PNG_FILTER_NONE, PNG_FILTER_SUB, PNG_FILTER_UP, etc).
1036 @li @c wxIMAGE_OPTION_PNG_COMPRESSION_LEVEL: Compression level (0..9) for
1037 saving a PNG file. An high value creates smaller-but-slower PNG file.
1038 Note that unlike other formats (e.g. JPEG) the PNG format is always
1039 lossless and thus this compression level doesn't tradeoff the image
1040 quality.
1041 @li @c wxIMAGE_OPTION_PNG_COMPRESSION_MEM_LEVEL: Compression memory usage
1042 level (1..9) for saving a PNG file. An high value means the saving
1043 process consumes more memory, but may create smaller PNG file.
1044 @li @c wxIMAGE_OPTION_PNG_COMPRESSION_STRATEGY: Possible values are 0 for
1045 default strategy, 1 for filter, and 2 for Huffman-only.
1046 You can use OptiPNG (http://optipng.sourceforge.net/) to get a suitable
1047 value for your application.
1048 @li @c wxIMAGE_OPTION_PNG_COMPRESSION_BUFFER_SIZE: Internal buffer size
1049 (in bytes) for saving a PNG file. Ideally this should be as big as
1050 the resulting PNG file. Use this option if your application produces
1051 images with small size variation.
1052
1053 @param name
1054 The name of the option, case-insensitive.
1055 @return
1056 The value of the option or 0 if not found.
1057 Use HasOption() if 0 can be a valid option value.
1058
1059 @see SetOption(), GetOption()
1060 */
1061 int GetOptionInt(const wxString& name) const;
1062
1063 /**
1064 Get the current mask colour or find a suitable unused colour that could be
1065 used as a mask colour. Returns @true if the image currently has a mask.
1066 */
1067 bool GetOrFindMaskColour(unsigned char* r, unsigned char* g,
1068 unsigned char* b) const;
1069
1070 /**
1071 Returns the palette associated with the image.
1072 Currently the palette is only used when converting to wxBitmap under Windows.
1073
1074 Some of the wxImage handlers have been modified to set the palette if
1075 one exists in the image file (usually 256 or less colour images in
1076 GIF or PNG format).
1077 */
1078 const wxPalette& GetPalette() const;
1079
1080 /**
1081 Returns a sub image of the current one as long as the rect belongs entirely
1082 to the image.
1083 */
1084 wxImage GetSubImage(const wxRect& rect) const;
1085
1086 /**
1087 Gets the type of image found by LoadFile() or specified with SaveFile().
1088
1089 @since 2.9.0
1090 */
1091 wxBitmapType GetType() const;
1092
1093 /**
1094 Returns @true if this image has alpha channel, @false otherwise.
1095
1096 @see GetAlpha(), SetAlpha()
1097 */
1098 bool HasAlpha() const;
1099
1100 /**
1101 Returns @true if there is a mask active, @false otherwise.
1102 */
1103 bool HasMask() const;
1104
1105 /**
1106 Returns @true if the given option is present.
1107 The function is case-insensitive to @a name.
1108
1109 The lists of the currently supported options are in GetOption() and
1110 GetOptionInt() function docs.
1111
1112 @see SetOption(), GetOption(), GetOptionInt()
1113 */
1114 bool HasOption(const wxString& name) const;
1115
1116 /**
1117 Returns @true if image data is present.
1118 */
1119 bool IsOk() const;
1120
1121 /**
1122 Returns @true if the given pixel is transparent, i.e. either has the mask
1123 colour if this image has a mask or if this image has alpha channel and alpha
1124 value of this pixel is strictly less than @a threshold.
1125 */
1126 bool IsTransparent(int x, int y,
1127 unsigned char threshold = wxIMAGE_ALPHA_THRESHOLD) const;
1128
1129 //@}
1130
1131
1132 /**
1133 @name Loading and saving functions
1134 */
1135 //@{
1136
1137 /**
1138 Loads an image from an input stream.
1139
1140 @param stream
1141 Opened input stream from which to load the image.
1142 Currently, the stream must support seeking.
1143 @param type
1144 May be one of the following:
1145 @li wxBITMAP_TYPE_BMP: Load a Windows bitmap file.
1146 @li wxBITMAP_TYPE_GIF: Load a GIF bitmap file.
1147 @li wxBITMAP_TYPE_JPEG: Load a JPEG bitmap file.
1148 @li wxBITMAP_TYPE_PNG: Load a PNG bitmap file.
1149 @li wxBITMAP_TYPE_PCX: Load a PCX bitmap file.
1150 @li wxBITMAP_TYPE_PNM: Load a PNM bitmap file.
1151 @li wxBITMAP_TYPE_TIF: Load a TIFF bitmap file.
1152 @li wxBITMAP_TYPE_TGA: Load a TGA bitmap file.
1153 @li wxBITMAP_TYPE_XPM: Load a XPM bitmap file.
1154 @li wxBITMAP_TYPE_ICO: Load a Windows icon file (ICO).
1155 @li wxBITMAP_TYPE_CUR: Load a Windows cursor file (CUR).
1156 @li wxBITMAP_TYPE_ANI: Load a Windows animated cursor file (ANI).
1157 @li wxBITMAP_TYPE_ANY: Will try to autodetect the format.
1158 @param index
1159 Index of the image to load in the case that the image file contains
1160 multiple images. This is only used by GIF, ICO and TIFF handlers.
1161 The default value (-1) means "choose the default image" and is
1162 interpreted as the first image (index=0) by the GIF and TIFF handler
1163 and as the largest and most colourful one by the ICO handler.
1164
1165 @return @true if the operation succeeded, @false otherwise.
1166 If the optional index parameter is out of range, @false is
1167 returned and a call to wxLogError() takes place.
1168
1169 @remarks Depending on how wxWidgets has been configured, not all formats
1170 may be available.
1171
1172 @note
1173 You can use GetOptionInt() to get the hotspot when loading cursor files:
1174 @code
1175 int hotspot_x = image.GetOptionInt(wxIMAGE_OPTION_CUR_HOTSPOT_X);
1176 int hotspot_y = image.GetOptionInt(wxIMAGE_OPTION_CUR_HOTSPOT_Y);
1177 @endcode
1178
1179 @see SaveFile()
1180 */
1181 virtual bool LoadFile(wxInputStream& stream,
1182 wxBitmapType type = wxBITMAP_TYPE_ANY,
1183 int index = -1);
1184
1185 /**
1186 Loads an image from a file.
1187 If no handler type is provided, the library will try to autodetect the format.
1188
1189 @param name
1190 Name of the file from which to load the image.
1191 @param type
1192 See the description in the LoadFile(wxInputStream&, wxBitmapType, int) overload.
1193 @param index
1194 See the description in the LoadFile(wxInputStream&, wxBitmapType, int) overload.
1195 */
1196 virtual bool LoadFile(const wxString& name,
1197 wxBitmapType type = wxBITMAP_TYPE_ANY,
1198 int index = -1);
1199
1200 /**
1201 Loads an image from a file.
1202 If no handler type is provided, the library will try to autodetect the format.
1203
1204 @param name
1205 Name of the file from which to load the image.
1206 @param mimetype
1207 MIME type string (for example 'image/jpeg')
1208 @param index
1209 See the description in the LoadFile(wxInputStream&, wxBitmapType, int) overload.
1210 */
1211 virtual bool LoadFile(const wxString& name, const wxString& mimetype,
1212 int index = -1);
1213
1214 /**
1215 Loads an image from an input stream.
1216
1217 @param stream
1218 Opened input stream from which to load the image.
1219 Currently, the stream must support seeking.
1220 @param mimetype
1221 MIME type string (for example 'image/jpeg')
1222 @param index
1223 See the description in the LoadFile(wxInputStream&, wxBitmapType, int) overload.
1224 */
1225 virtual bool LoadFile(wxInputStream& stream, const wxString& mimetype,
1226 int index = -1);
1227
1228 /**
1229 Saves an image in the given stream.
1230
1231 @param stream
1232 Opened output stream to save the image to.
1233 @param mimetype
1234 MIME type.
1235
1236 @return @true if the operation succeeded, @false otherwise.
1237
1238 @remarks Depending on how wxWidgets has been configured, not all formats
1239 may be available.
1240
1241 @note
1242 You can use SetOption() to set the hotspot when saving an image
1243 into a cursor file (default hotspot is in the centre of the image):
1244 @code
1245 image.SetOption(wxIMAGE_OPTION_CUR_HOTSPOT_X, hotspotX);
1246 image.SetOption(wxIMAGE_OPTION_CUR_HOTSPOT_Y, hotspotY);
1247 @endcode
1248
1249 @see LoadFile()
1250 */
1251 virtual bool SaveFile(wxOutputStream& stream,
1252 const wxString& mimetype) const;
1253
1254 /**
1255 Saves an image in the named file.
1256
1257 @param name
1258 Name of the file to save the image to.
1259 @param type
1260 Currently these types can be used:
1261 @li wxBITMAP_TYPE_BMP: Save a BMP image file.
1262 @li wxBITMAP_TYPE_JPEG: Save a JPEG image file.
1263 @li wxBITMAP_TYPE_PNG: Save a PNG image file.
1264 @li wxBITMAP_TYPE_PCX: Save a PCX image file
1265 (tries to save as 8-bit if possible, falls back to 24-bit otherwise).
1266 @li wxBITMAP_TYPE_PNM: Save a PNM image file (as raw RGB always).
1267 @li wxBITMAP_TYPE_TIFF: Save a TIFF image file.
1268 @li wxBITMAP_TYPE_XPM: Save a XPM image file.
1269 @li wxBITMAP_TYPE_ICO: Save a Windows icon file (ICO).
1270 The size may be up to 255 wide by 127 high. A single image is saved
1271 in 8 colors at the size supplied.
1272 @li wxBITMAP_TYPE_CUR: Save a Windows cursor file (CUR).
1273 */
1274 virtual bool SaveFile(const wxString& name, wxBitmapType type) const;
1275
1276 /**
1277 Saves an image in the named file.
1278
1279 @param name
1280 Name of the file to save the image to.
1281 @param mimetype
1282 MIME type.
1283 */
1284 virtual bool SaveFile(const wxString& name, const wxString& mimetype) const;
1285
1286 /**
1287 Saves an image in the named file.
1288
1289 File type is determined from the extension of the file name.
1290 Note that this function may fail if the extension is not recognized!
1291 You can use one of the forms above to save images to files with
1292 non-standard extensions.
1293
1294 @param name
1295 Name of the file to save the image to.
1296 */
1297 virtual bool SaveFile(const wxString& name) const;
1298
1299 /**
1300 Saves an image in the given stream.
1301
1302 @param stream
1303 Opened output stream to save the image to.
1304 @param type
1305 MIME type.
1306 */
1307 virtual bool SaveFile(wxOutputStream& stream, wxBitmapType type) const;
1308
1309 //@}
1310
1311
1312
1313 /**
1314 @name Setters
1315 */
1316 //@{
1317
1318 /**
1319 This function is similar to SetData() and has similar restrictions.
1320
1321 The pointer passed to it may however be @NULL in which case the function
1322 will allocate the alpha array internally -- this is useful to add alpha
1323 channel data to an image which doesn't have any.
1324
1325 If the pointer is not @NULL, it must have one byte for each image pixel
1326 and be allocated with malloc().
1327 wxImage takes ownership of the pointer and will free it unless @a static_data
1328 parameter is set to @true -- in this case the caller should do it.
1329 */
1330 void SetAlpha(unsigned char* alpha = NULL,
1331 bool static_data = false);
1332
1333 /**
1334 Sets the alpha value for the given pixel.
1335 This function should only be called if the image has alpha channel data,
1336 use HasAlpha() to check for this.
1337 */
1338 void SetAlpha(int x, int y, unsigned char alpha);
1339
1340 /**
1341 Sets the image data without performing checks.
1342
1343 The data given must have the size (width*height*3) or results will be
1344 unexpected. Don't use this method if you aren't sure you know what you
1345 are doing.
1346
1347 The data must have been allocated with @c malloc(), @b NOT with
1348 @c operator new.
1349
1350 If @a static_data is @false, after this call the pointer to the data is
1351 owned by the wxImage object, that will be responsible for deleting it.
1352 Do not pass to this function a pointer obtained through GetData().
1353 */
1354 void SetData(unsigned char* data, bool static_data = false);
1355
1356 /**
1357 @overload
1358 */
1359 void SetData(unsigned char* data, int new_width, int new_height,
1360 bool static_data = false);
1361
1362 /**
1363 Specifies whether there is a mask or not.
1364
1365 The area of the mask is determined by the current mask colour.
1366 */
1367 void SetMask(bool hasMask = true);
1368
1369 /**
1370 Sets the mask colour for this image (and tells the image to use the mask).
1371 */
1372 void SetMaskColour(unsigned char red, unsigned char green,
1373 unsigned char blue);
1374
1375 /**
1376 Sets image's mask so that the pixels that have RGB value of mr,mg,mb in
1377 mask will be masked in the image.
1378
1379 This is done by first finding an unused colour in the image, setting
1380 this colour as the mask colour and then using this colour to draw all
1381 pixels in the image who corresponding pixel in mask has given RGB value.
1382
1383 The parameter @a mask is the mask image to extract mask shape from.
1384 It must have the same dimensions as the image.
1385
1386 The parameters @a mr, @a mg, @a mb are the RGB values of the pixels in
1387 mask that will be used to create the mask.
1388
1389 @return Returns @false if mask does not have same dimensions as the image
1390 or if there is no unused colour left. Returns @true if the mask
1391 was successfully applied.
1392
1393 @note
1394 Note that this method involves computing the histogram, which is a
1395 computationally intensive operation.
1396 */
1397 bool SetMaskFromImage(const wxImage& mask, unsigned char mr,
1398 unsigned char mg,
1399 unsigned char mb);
1400
1401 /**
1402 Sets a user-defined option. The function is case-insensitive to @a name.
1403
1404 For example, when saving as a JPEG file, the option @b quality is
1405 used, which is a number between 0 and 100 (0 is terrible, 100 is very good).
1406
1407 The lists of the currently supported options are in GetOption() and
1408 GetOptionInt() function docs.
1409
1410 @see GetOption(), GetOptionInt(), HasOption()
1411 */
1412 void SetOption(const wxString& name, const wxString& value);
1413
1414 /**
1415 @overload
1416 */
1417 void SetOption(const wxString& name, int value);
1418
1419 /**
1420 Associates a palette with the image.
1421
1422 The palette may be used when converting wxImage to wxBitmap (MSW only at present)
1423 or in file save operations (none as yet).
1424 */
1425 void SetPalette(const wxPalette& palette);
1426
1427 /**
1428 Sets the colour of the pixels within the given rectangle.
1429
1430 This routine performs bounds-checks for the coordinate so it can be considered
1431 a safe way to manipulate the data.
1432 */
1433 void SetRGB(const wxRect& rect,
1434 unsigned char red,
1435 unsigned char green,
1436 unsigned char blue);
1437
1438 /**
1439 Set the type of image returned by GetType().
1440
1441 This method is mostly used internally by the library but can also be
1442 called from the user code if the image was created from data in the
1443 given bitmap format without using LoadFile() (which would set the type
1444 correctly automatically).
1445
1446 Notice that the image must be created before this function is called.
1447
1448 @since 2.9.0
1449
1450 @param type
1451 One of bitmap type constants, @c wxBITMAP_TYPE_INVALID is a valid
1452 value for it and can be used to reset the bitmap type to default
1453 but @c wxBITMAP_TYPE_MAX is not allowed here.
1454 */
1455 void SetType(wxBitmapType type);
1456
1457 //@}
1458
1459
1460
1461 /**
1462 @name Handler management functions
1463 */
1464 //@{
1465
1466 /**
1467 Register an image handler.
1468 See @ref image_handlers for a list of the available handlers.
1469 */
1470 static void AddHandler(wxImageHandler* handler);
1471
1472 /**
1473 Deletes all image handlers.
1474 This function is called by wxWidgets on exit.
1475 */
1476 static void CleanUpHandlers();
1477
1478 /**
1479 Finds the handler with the given name.
1480
1481 @param name
1482 The handler name.
1483
1484 @return A pointer to the handler if found, @NULL otherwise.
1485
1486 @see wxImageHandler
1487 */
1488 static wxImageHandler* FindHandler(const wxString& name);
1489
1490 /**
1491 Finds the handler associated with the given extension and type.
1492
1493 @param extension
1494 The file extension, such as "bmp".
1495 @param imageType
1496 The image type; one of the ::wxBitmapType values.
1497
1498 @return A pointer to the handler if found, @NULL otherwise.
1499
1500 @see wxImageHandler
1501 */
1502 static wxImageHandler* FindHandler(const wxString& extension,
1503 wxBitmapType imageType);
1504
1505 /**
1506 Finds the handler associated with the given image type.
1507
1508 @param imageType
1509 The image type; one of the ::wxBitmapType values.
1510
1511 @return A pointer to the handler if found, @NULL otherwise.
1512
1513 @see wxImageHandler
1514 */
1515 static wxImageHandler* FindHandler(wxBitmapType imageType);
1516
1517 /**
1518 Finds the handler associated with the given MIME type.
1519
1520 @param mimetype
1521 MIME type.
1522
1523 @return A pointer to the handler if found, @NULL otherwise.
1524
1525 @see wxImageHandler
1526 */
1527 static wxImageHandler* FindHandlerMime(const wxString& mimetype);
1528
1529 /**
1530 Returns the static list of image format handlers.
1531
1532 @see wxImageHandler
1533 */
1534 static wxList& GetHandlers();
1535
1536 /**
1537 Internal use only. Adds standard image format handlers.
1538 It only install wxBMPHandler for the time being, which is used by wxBitmap.
1539
1540 This function is called by wxWidgets on startup, and shouldn't be called by
1541 the user.
1542
1543 @see wxImageHandler, wxInitAllImageHandlers(), wxQuantize
1544 */
1545 static void InitStandardHandlers();
1546
1547 /**
1548 Adds a handler at the start of the static list of format handlers.
1549
1550 @param handler
1551 A new image format handler object. There is usually only one instance
1552 of a given handler class in an application session.
1553
1554 @see wxImageHandler
1555 */
1556 static void InsertHandler(wxImageHandler* handler);
1557
1558 /**
1559 Finds the handler with the given name, and removes it.
1560 The handler is not deleted.
1561
1562 @param name
1563 The handler name.
1564
1565 @return @true if the handler was found and removed, @false otherwise.
1566
1567 @see wxImageHandler
1568 */
1569 static bool RemoveHandler(const wxString& name);
1570
1571 //@}
1572
1573
1574 /**
1575 Returns @true if the current image handlers can read this file
1576 */
1577 static bool CanRead(const wxString& filename);
1578
1579 //@{
1580 /**
1581 If the image file contains more than one image and the image handler is
1582 capable of retrieving these individually, this function will return the
1583 number of available images.
1584
1585 For the overload taking the parameter @a filename, that's the name
1586 of the file to query.
1587 For the overload taking the parameter @a stream, that's the ppened input
1588 stream with image data. Currently, the stream must support seeking.
1589
1590 The parameter @a type may be one of the following values:
1591 @li wxBITMAP_TYPE_BMP: Load a Windows bitmap file.
1592 @li wxBITMAP_TYPE_GIF: Load a GIF bitmap file.
1593 @li wxBITMAP_TYPE_JPEG: Load a JPEG bitmap file.
1594 @li wxBITMAP_TYPE_PNG: Load a PNG bitmap file.
1595 @li wxBITMAP_TYPE_PCX: Load a PCX bitmap file.
1596 @li wxBITMAP_TYPE_PNM: Load a PNM bitmap file.
1597 @li wxBITMAP_TYPE_TIF: Load a TIFF bitmap file.
1598 @li wxBITMAP_TYPE_TGA: Load a TGA bitmap file.
1599 @li wxBITMAP_TYPE_XPM: Load a XPM bitmap file.
1600 @li wxBITMAP_TYPE_ICO: Load a Windows icon file (ICO).
1601 @li wxBITMAP_TYPE_CUR: Load a Windows cursor file (CUR).
1602 @li wxBITMAP_TYPE_ANI: Load a Windows animated cursor file (ANI).
1603 @li wxBITMAP_TYPE_ANY: Will try to autodetect the format.
1604
1605 @return Number of available images. For most image handlers, this is 1
1606 (exceptions are TIFF and ICO formats).
1607 */
1608 static int GetImageCount(const wxString& filename,
1609 wxBitmapType type = wxBITMAP_TYPE_ANY);
1610 static int GetImageCount(wxInputStream& stream,
1611 wxBitmapType type = wxBITMAP_TYPE_ANY);
1612 //@}
1613
1614 /**
1615 Iterates all registered wxImageHandler objects, and returns a string containing
1616 file extension masks suitable for passing to file open/save dialog boxes.
1617
1618 @return The format of the returned string is @c "(*.ext1;*.ext2)|*.ext1;*.ext2".
1619 It is usually a good idea to prepend a description before passing
1620 the result to the dialog.
1621 Example:
1622 @code
1623 wxFileDialog FileDlg( this, "Choose Image", ::wxGetCwd(), "",
1624 _("Image Files ") + wxImage::GetImageExtWildcard(),
1625 wxFD_OPEN );
1626 @endcode
1627
1628 @see wxImageHandler
1629 */
1630 static wxString GetImageExtWildcard();
1631
1632 /**
1633 Converts a color in RGB color space to HSV color space.
1634 */
1635 static wxImage::HSVValue RGBtoHSV(const wxImage::RGBValue& rgb);
1636
1637 /**
1638 Converts a color in HSV color space to RGB color space.
1639 */
1640 static wxImage::RGBValue HSVtoRGB(const wxImage::HSVValue& hsv);
1641 };
1642
1643 /**
1644 An instance of an empty image without an alpha channel.
1645 */
1646 wxImage wxNullImage;
1647
1648
1649 // ============================================================================
1650 // Global functions/macros
1651 // ============================================================================
1652
1653 /** @addtogroup group_funcmacro_appinitterm */
1654 //@{
1655
1656 /**
1657 Initializes all available image handlers. For a list of available handlers,
1658 see wxImage.
1659 If you don't need/want all image handlers loaded
1660
1661 @see wxImage, wxImageHandler
1662
1663 @header{wx/image.h}
1664 */
1665 void wxInitAllImageHandlers();
1666
1667 //@}
1668