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1 \section{\class{wxImage}}\label{wximage}
2
3 This class encapsulates a platform-independent image. An image can be created
4 from data, or using the constructor taking a wxBitmap object. An image
5 can be loaded from a file in a variety of formats, and is extensible to new formats
6 via image format handlers. Functions are available to set and get image bits, so
7 it can be used for basic image manipulation.
8
9 A wxImage cannot (currently) be drawn directly to a \helpref{wxDC}{wxdc}. Instead,
10 a platform-specific \helpref{wxBitmap}{wxbitmap} object must be created from it using
11 the \helpref{ConvertToBitmap}{wximageconverttobitmap} function. This bitmap can then
12 be drawn in a device context, using \helpref{wxDC::DrawBitmap}{wxdcdrawbitmap}.
13
14 One colour value of the image may be used as a mask colour which will lead to the automatic
15 creation of a \helpref{wxMask}{wxmask} object associated to the bitmap object.
16
17 \wxheading{Available image handlers}
18
19 The following image handlers are available. {\bf wxBMPHandler} is always
20 installed by default. To use other image formats, install the appropiate
21 handler with \helpref{wxImage::AddHandler}{wximageaddhandler} or
22 \helpref{wxInitAllImageHandlers}{wxinitallimagehandlers}.
23
24 \twocolwidtha{5cm}%
25 \begin{twocollist}
26 \twocolitem{{\bf \indexit{wxBMPHandler}}}{Only for loading, always installed.}
27 \twocolitem{{\bf \indexit{wxPNGHandler}}}{For loading and saving.}
28 \twocolitem{{\bf \indexit{wxJPEGHandler}}}{For loading and saving.}
29 \twocolitem{{\bf \indexit{wxGIFHandler}}}{Only for loading, due to legal issues.}
30 \twocolitem{{\bf \indexit{wxPCXHandler}}}{For loading and saving (see below).}
31 \twocolitem{{\bf \indexit{wxPNMHandler}}}{For loading and saving (see below).}
32 \twocolitem{{\bf \indexit{wxTIFFHandler}}}{For loading.}
33 \end{twocollist}
34
35 When saving in PCX format, {\bf wxPCXHandler} will count the number of
36 different colours in the image; if there are 256 or less colours, it will
37 save as 8 bit, else it will save as 24 bit.
38
39 Loading PNMs only works for ASCII or raw RGB images. When saving in
40 PNM format, {\bf wxPNMHandler} will always save as raw RGB.
41
42 \wxheading{Derived from}
43
44 \helpref{wxObject}{wxobject}
45
46 \wxheading{Include files}
47
48 <wx/image.h>
49
50 \wxheading{See also}
51
52 \helpref{wxBitmap}{wxbitmap},
53 \helpref{wxInitAllImageHandlers}{wxinitallimagehandlers}
54
55 \latexignore{\rtfignore{\wxheading{Members}}}
56
57 \membersection{wxImage::wxImage}\label{wximageconstr}
58
59 \func{}{wxImage}{\void}
60
61 Default constructor.
62
63 \func{}{wxImage}{\param{const wxImage\& }{image}}
64
65 Copy constructor.
66
67 \func{}{wxImage}{\param{const wxBitmap\&}{ bitmap}}
68
69 Constructs an image from a platform-dependent bitmap. This preserves
70 mask information so that bitmaps and images can be converted back
71 and forth without loss in that respect.
72
73 \func{}{wxImage}{\param{int}{ width}, \param{int}{ height}}
74
75 Creates an image with the given width and height.
76
77 \func{}{wxImage}{\param{int}{ width}, \param{int}{ height}, \param{unsigned char*}{ data}, \param{bool}{ static_data=FALSE}}
78
79 Creates an image from given data with the given width and height. If
80 {\it static_data} is TRUE, then wxImage will not delete the actual
81 image data in its destructor, otherwise it will free it by calling
82 {\it free()}.
83
84 \func{}{wxImage}{\param{const wxString\& }{name}, \param{long}{ type = wxBITMAP\_TYPE\_ANY}}
85
86 \func{}{wxImage}{\param{const wxString\& }{name}, \param{const wxString\&}{ mimetype}}
87
88 Loads an image from a file.
89
90 \func{}{wxImage}{\param{wxInputStream\& }{stream}, \param{long}{ type = wxBITMAP\_TYPE\_ANY}}
91
92 \func{}{wxImage}{\param{wxInputStream\& }{stream}, \param{const wxString\&}{ mimetype}}
93
94 Loads an image from an input stream.
95
96 \wxheading{Parameters}
97
98 \docparam{width}{Specifies the width of the image.}
99
100 \docparam{height}{Specifies the height of the image.}
101
102 \docparam{name}{Name of the file from which to load the image.}
103
104 \docparam{stream}{Opened input stream from which to load the image. Currently, the stream must support seeking.}
105
106 \docparam{type}{May be one of the following:
107
108 \twocolwidtha{5cm}%
109 \begin{twocollist}
110 \twocolitem{{\bf \indexit{wxBITMAP\_TYPE\_BMP}}}{Load a Windows bitmap file.}
111 \twocolitem{{\bf \indexit{wxBITMAP\_TYPE\_GIF}}}{Load a GIF bitmap file.}
112 \twocolitem{{\bf \indexit{wxBITMAP\_TYPE\_JPEG}}}{Load a JPEG bitmap file.}
113 \twocolitem{{\bf \indexit{wxBITMAP\_TYPE\_PNG}}}{Load a PNG bitmap file.}
114 \twocolitem{{\bf \indexit{wxBITMAP\_TYPE\_PCX}}}{Load a PCX bitmap file.}
115 \twocolitem{{\bf \indexit{wxBITMAP\_TYPE\_PNM}}}{Load a PNM bitmap file.}
116 \twocolitem{{\bf \indexit{wxBITMAP\_TYPE\_TIF}}}{Load a TIFF bitmap file.}
117 \twocolitem{{\bf \indexit{wxBITMAP\_TYPE\_ANY}}}{Will try to autodetect the format.}
118 \end{twocollist}}
119
120 \docparam{mimetype}{MIME type string (for example 'image/jpeg')}
121
122 \wxheading{Remarks}
123
124 Depending on how wxWindows has been configured, not all formats may be available.
125
126 Note: any handler other than BMP must be previously
127 initialized with \helpref{wxImage::AddHandler}{wximageaddhandler} or
128 \helpref{wxInitAllImageHandlers}{wxinitallimagehandlers}.
129
130 \wxheading{See also}
131
132 \helpref{wxImage::LoadFile}{wximageloadfile}
133
134 \pythonnote{Constructors supported by wxPython are:\par
135 \indented{2cm}{\begin{twocollist}
136 \twocolitem{{\bf wxImage(name, flag)}}{Loads an image from a file}
137 \twocolitem{{\bf wxNullImage()}}{Create a null image (has no size or
138 image data)}
139 \twocolitem{{\bf wxEmptyImage(width, height)}}{Creates an empty image
140 of the given size}
141 \twocolitem{{\bf wxImageFromMime(name, mimetype}}{Creates an image from
142 the given file of the given mimetype}
143 \twocolitem{{\bf wxImageFromBitmap(bitmap)}}{Creates an image from a
144 platform-dependent bitmap}
145 \end{twocollist}}
146 }
147
148 \membersection{wxImage::\destruct{wxImage}}
149
150 \func{}{\destruct{wxImage}}{\void}
151
152 Destructor.
153
154 \membersection{wxImage::AddHandler}\label{wximageaddhandler}
155
156 \func{static void}{AddHandler}{\param{wxImageHandler*}{ handler}}
157
158 Adds a handler to the end of the static list of format handlers.
159
160 \docparam{handler}{A new image format handler object. There is usually only one instance
161 of a given handler class in an application session.}
162
163 \wxheading{See also}
164
165 \helpref{wxImageHandler}{wximagehandler}
166
167 \pythonnote{In wxPython this static method is named {\tt wxImage_AddHandler}.}
168 \membersection{wxImage::CleanUpHandlers}
169
170 \func{static void}{CleanUpHandlers}{\void}
171
172 Deletes all image handlers.
173
174 This function is called by wxWindows on exit.
175
176 \membersection{wxImage::ConvertToBitmap}\label{wximageconverttobitmap}
177
178 \constfunc{wxBitmap}{ConvertToBitmap}{\void}
179
180 Converts the image to a platform-specific bitmap object. This has to be done
181 to actually display an image as you cannot draw an image directly on a window.
182 The resulting bitmap will use the colour depth of the current system which entails
183 that a colour reduction has to take place.
184
185 When in 8-bit mode (PseudoColour mode), the GTK port will use a color cube created
186 on program start-up to look up colors. This ensures a very fast conversion, but
187 the image quality won't be perfect (and could be better for photo images using more
188 sophisticated dithering algorithms).
189
190 \membersection{wxImage::Copy}\label{wximagecopy}
191
192 \constfunc{wxImage}{Copy}{\void}
193
194 Returns an identical copy of the image.
195
196 \membersection{wxImage::Create}\label{wximagecreate}
197
198 \func{bool}{Create}{\param{int}{ width}, \param{int}{ height}}
199
200 Creates a fresh image.
201
202 \wxheading{Parameters}
203
204 \docparam{width}{The width of the image in pixels.}
205
206 \docparam{height}{The height of the image in pixels.}
207
208 \wxheading{Return value}
209
210 TRUE if the call succeeded, FALSE otherwise.
211
212 \membersection{wxImage::Destroy}\label{wximagedestroy}
213
214 \func{bool}{Destroy}{\void}
215
216 Destroys the image data.
217
218 \membersection{wxImage::FindHandler}
219
220 \func{static wxImageHandler*}{FindHandler}{\param{const wxString\& }{name}}
221
222 Finds the handler with the given name.
223
224 \func{static wxImageHandler*}{FindHandler}{\param{const wxString\& }{extension}, \param{long}{ imageType}}
225
226 Finds the handler associated with the given extension and type.
227
228 \func{static wxImageHandler*}{FindHandler}{\param{long }{imageType}}
229
230 Finds the handler associated with the given image type.
231
232 \func{static wxImageHandler*}{FindHandlerMime}{\param{const wxString\& }{mimetype}}
233
234 Finds the handler associated with the given MIME type.
235
236 \docparam{name}{The handler name.}
237
238 \docparam{extension}{The file extension, such as ``bmp".}
239
240 \docparam{imageType}{The image type, such as wxBITMAP\_TYPE\_BMP.}
241
242 \docparam{mimetype}{MIME type.}
243
244 \wxheading{Return value}
245
246 A pointer to the handler if found, NULL otherwise.
247
248 \wxheading{See also}
249
250 \helpref{wxImageHandler}{wximagehandler}
251
252 \membersection{wxImage::GetBlue}\label{wximagegetblue}
253
254 \constfunc{unsigned char}{GetBlue}{\param{int}{ x}, \param{int}{ y}}
255
256 Returns the blue intensity at the given coordinate.
257
258 \membersection{wxImage::GetData}\label{wximagegetdata}
259
260 \constfunc{unsigned char*}{GetData}{\void}
261
262 Returns the image data as an array. This is most often used when doing
263 direct image manipulation. The return value points to an array of
264 chararcters in RGBGBRGB... format.
265
266 \membersection{wxImage::GetGreen}\label{wximagegetgreen}
267
268 \constfunc{unsigned char}{GetGreen}{\param{int}{ x}, \param{int}{ y}}
269
270 Returns the green intensity at the given coordinate.
271
272 \membersection{wxImage::GetRed}\label{wximagegetred}
273
274 \constfunc{unsigned char}{GetRed}{\param{int}{ x}, \param{int}{ y}}
275
276 Returns the red intensity at the given coordinate.
277
278 \membersection{wxImage::GetHandlers}
279
280 \func{static wxList\&}{GetHandlers}{\void}
281
282 Returns the static list of image format handlers.
283
284 \wxheading{See also}
285
286 \helpref{wxImageHandler}{wximagehandler}
287
288 \membersection{wxImage::GetHeight}\label{wximagegetheight}
289
290 \constfunc{int}{GetHeight}{\void}
291
292 Gets the height of the image in pixels.
293
294 \membersection{wxImage::GetMaskBlue}\label{wximagegetmaskblue}
295
296 \constfunc{unsigned char}{GetMaskBlue}{\void}
297
298 Gets the blue value of the mask colour.
299
300 \membersection{wxImage::GetMaskGreen}\label{wximagegetmaskgreen}
301
302 \constfunc{unsigned char}{GetMaskGreen}{\void}
303
304 Gets the green value of the mask colour.
305
306 \membersection{wxImage::GetMaskRed}\label{wximagegetmaskred}
307
308 \constfunc{unsigned char}{GetMaskRed}{\void}
309
310 Gets the red value of the mask colour.
311
312 \membersection{wxImage::GetSubImage}\label{wximagegetsubimage}
313
314 \constfunc{wxImage}{GetSubImage}{\param{const wxRect\&}{ rect}}
315
316 Returns a sub image of the current one as long as the rect belongs entirely to
317 the image.
318
319 \membersection{wxImage::GetWidth}\label{wximagegetwidth}
320
321 \constfunc{int}{GetWidth}{\void}
322
323 Gets the width of the image in pixels.
324
325 \wxheading{See also}
326
327 \helpref{wxImage::GetHeight}{wximagegetheight}
328
329 \membersection{wxImage::HasMask}\label{wximagehasmask}
330
331 \constfunc{bool}{HasMask}{\void}
332
333 Returns TRUE if there is a mask active, FALSE otherwise.
334
335 \membersection{wxImage::InitStandardHandlers}
336
337 \func{static void}{InitStandardHandlers}{\void}
338
339 Internal use only. Adds standard image format handlers. It only install BMP
340 for the time being, which is used by wxBitmap.
341
342 This function is called by wxWindows on startup, and shouldn't be called by
343 the user.
344
345 \wxheading{See also}
346
347 \helpref{wxImageHandler}{wximagehandler},
348 \helpref{wxInitAllImageHandlers}{wxinitallimagehandlers}
349
350 \membersection{wxImage::InsertHandler}
351
352 \func{static void}{InsertHandler}{\param{wxImageHandler*}{ handler}}
353
354 Adds a handler at the start of the static list of format handlers.
355
356 \docparam{handler}{A new image format handler object. There is usually only one instance
357 of a given handler class in an application session.}
358
359 \wxheading{See also}
360
361 \helpref{wxImageHandler}{wximagehandler}
362
363 \membersection{wxImage::LoadFile}\label{wximageloadfile}
364
365 \func{bool}{LoadFile}{\param{const wxString\&}{ name}, \param{long}{ type = wxBITMAP\_TYPE\_ANY}}
366
367 \func{bool}{LoadFile}{\param{const wxString\&}{ name}, \param{const wxString\&}{ mimetype}}
368
369 Loads an image from a file. If no handler type is provided, the library will
370 try to autodetect the format.
371
372 \func{bool}{LoadFile}{\param{wxInputStream\&}{ stream}, \param{long}{ type}}
373
374 \func{bool}{LoadFile}{\param{wxInputStream\&}{ stream}, \param{const wxString\&}{ mimetype}}
375
376 Loads an image from an input stream.
377
378 \wxheading{Parameters}
379
380 \docparam{name}{Name of the file from which to load the image.}
381
382 \docparam{stream}{Opened input stream from which to load the image. Currently, the stream must support seeking.}
383
384 \docparam{type}{One of the following values:
385
386 \twocolwidtha{5cm}%
387 \begin{twocollist}
388 \twocolitem{{\bf wxBITMAP\_TYPE\_BMP}}{Load a Windows image file.}
389 \twocolitem{{\bf wxBITMAP\_TYPE\_GIF}}{Load a GIF image file.}
390 \twocolitem{{\bf wxBITMAP\_TYPE\_JPEG}}{Load a JPEG image file.}
391 \twocolitem{{\bf wxBITMAP\_TYPE\_PCX}}{Load a PCX image file.}
392 \twocolitem{{\bf wxBITMAP\_TYPE\_PNG}}{Load a PNG image file.}
393 \twocolitem{{\bf wxBITMAP\_TYPE\_PNM}}{Load a PNM image file.}
394 \twocolitem{{\bf wxBITMAP\_TYPE\_TIF}}{Load a TIFF image file.}
395 \twocolitem{{\bf wxBITMAP\_TYPE\_ANY}}{Will try to autodetect the format.}
396 \end{twocollist}}
397
398 \docparam{mimetype}{MIME type string (for example 'image/jpeg')}
399
400 \wxheading{Remarks}
401
402 Depending on how wxWindows has been configured, not all formats may be available.
403
404 \wxheading{Return value}
405
406 TRUE if the operation succeeded, FALSE otherwise.
407
408 \wxheading{See also}
409
410 \helpref{wxImage::SaveFile}{wximagesavefile}
411
412 \pythonnote{In place of a single overloaded method name, wxPython
413 implements the following methods:\par
414 \indented{2cm}{\begin{twocollist}
415 \twocolitem{{\bf LoadFile(filename, type)}}{Loads an image of the given
416 type from a file}
417 \twocolitem{{\bf LoadMimeFile(filename, mimetype)}}{Loads an image of the given
418 mimetype from a file}
419 \end{twocollist}}
420 }
421
422
423 \membersection{wxImage::Ok}\label{wximageok}
424
425 \constfunc{bool}{Ok}{\void}
426
427 Returns TRUE if image data is present.
428
429 \membersection{wxImage::RemoveHandler}
430
431 \func{static bool}{RemoveHandler}{\param{const wxString\& }{name}}
432
433 Finds the handler with the given name, and removes it. The handler
434 is not deleted.
435
436 \docparam{name}{The handler name.}
437
438 \wxheading{Return value}
439
440 TRUE if the handler was found and removed, FALSE otherwise.
441
442 \wxheading{See also}
443
444 \helpref{wxImageHandler}{wximagehandler}
445
446 \membersection{wxImage::SaveFile}\label{wximagesavefile}
447
448 \func{bool}{SaveFile}{\param{const wxString\& }{name}, \param{int}{ type}}
449
450 \func{bool}{SaveFile}{\param{const wxString\& }{name}, \param{const wxString\&}{ mimetype}}
451
452 Saves a image in the named file.
453
454 \func{bool}{SaveFile}{\param{wxOutputStream\& }{stream}, \param{int}{ type}}
455
456 \func{bool}{SaveFile}{\param{wxOutputStream\& }{stream}, \param{const wxString\&}{ mimetype}}
457
458 Saves a image in the given stream.
459
460 \wxheading{Parameters}
461
462 \docparam{name}{Name of the file to save the image to.}
463
464 \docparam{stream}{Opened output stream to save the image to.}
465
466 \docparam{type}{Currently three types can be used:
467
468 \twocolwidtha{5cm}%
469 \begin{twocollist}
470 \twocolitem{{\bf wxBITMAP\_TYPE\_JPEG}}{Save a JPEG image file.}
471 \twocolitem{{\bf wxBITMAP\_TYPE\_PNG}}{Save a PNG image file.}
472 \twocolitem{{\bf wxBITMAP\_TYPE\_PCX}}{Save a PCX image file (tries to save as 8-bit if possible, falls back to 24-bit otherwise).}
473 \twocolitem{{\bf wxBITMAP\_TYPE\_PNM}}{Save a PNM image file (as raw RGB always).}
474 \end{twocollist}}
475
476 \docparam{mimetype}{MIME type.}
477
478 \wxheading{Return value}
479
480 TRUE if the operation succeeded, FALSE otherwise.
481
482 \wxheading{Remarks}
483
484 Depending on how wxWindows has been configured, not all formats may be available.
485
486 \wxheading{See also}
487
488 \helpref{wxImage::LoadFile}{wximageloadfile}
489
490 \pythonnote{In place of a single overloaded method name, wxPython
491 implements the following methods:\par
492 \indented{2cm}{\begin{twocollist}
493 \twocolitem{{\bf SaveFile(filename, type)}}{Saves the image using the given
494 type to the named file}
495 \twocolitem{{\bf SaveMimeFile(filename, mimetype)}}{Saves the image using the given
496 mimetype to the named file}
497 \end{twocollist}}
498 }
499
500 \membersection{wxImage::Mirror}\label{wximagemirror}
501
502 \constfunc{wxImage}{Mirror}{\param{bool}{ horizontally = TRUE}}
503
504 Returns a mirrored copy of the image. The parameter {\it horizontally}
505 indicates the orientation.
506
507 \membersection{wxImage::Replace}\label{wximagereplace}
508
509 \func{void}{Replace}{\param{unsigned char}{ r1}, \param{unsigned char}{ g1}, \param{unsigned char}{ b1},
510 \param{unsigned char}{ r2}, \param{unsigned char}{ g2}, \param{unsigned char}{ b2}}
511
512 Replaces the colour specified by {\it r1,g1,b1} by the colour {\it r2,g2,b2}.
513
514 \membersection{wxImage::Rescale}\label{wximagerescale}
515
516 \func{wxImage \&}{Rescale}{\param{int}{ width}, \param{int}{ height}}
517
518 Changes the size of the image in-place: after a call to this function, the
519 image will have the given width and height.
520
521 Returns the (modified) image itself.
522
523 \wxheading{See also}
524
525 \helpref{Scale}{wximagescale}
526
527 \membersection{wxImage::Rotate}\label{wximagerotate}
528
529 \func{wxImage}{Rotate}{\param{double}{ angle}, \param{const wxPoint\& }{rotationCentre},
530 \param{bool}{ interpolating = TRUE}, \param{wxPoint*}{ offsetAfterRotation = NULL}}
531
532 Rotates the image about the given point, by {\it angle} radians. Passing TRUE
533 to {\it interpolating} results in better image quality, but is slower. If the
534 image has a mask, then the mask colour is used for the uncovered pixels in the
535 rotated image background. Else, black (rgb 0, 0, 0) will be used.
536
537 Returns the rotated image, leaving this image intact.
538
539 \membersection{wxImage::Rotate90}\label{wximagerotate90}
540
541 \constfunc{wxImage}{Rotate90}{\param{bool}{ clockwise = TRUE}}
542
543 Returns a copy of the image rotated 90 degrees in the direction
544 indicated by {\it clockwise}.
545
546 \membersection{wxImage::Scale}\label{wximagescale}
547
548 \constfunc{wxImage}{Scale}{\param{int}{ width}, \param{int}{ height}}
549
550 Returns a scaled version of the image. This is also useful for
551 scaling bitmaps in general as the only other way to scale bitmaps
552 is to blit a wxMemoryDC into another wxMemoryDC.
553
554 It may be mentioned that the GTK port uses this function internally
555 to scale bitmaps when using mapping modes in wxDC.
556
557 Example:
558
559 \begin{verbatim}
560 // get the bitmap from somewhere
561 wxBitmap bmp = ...;
562
563 // rescale it to have size of 32*32
564 if ( bmp.GetWidth() != 32 || bmp.GetHeight() != 32 )
565 {
566 wxImage image(bmp);
567 bmp = image.Scale(32, 32).ConvertToBitmap();
568
569 // another possibility:
570 image.Rescale(32, 32);
571 bmp = image;
572 }
573
574 \end{verbatim}
575
576 \wxheading{See also}
577
578 \helpref{Rescale}{wximagerescale}
579
580 \membersection{wxImage::SetData}\label{wximagesetdata}
581
582 \func{void}{SetData}{\param{unsigned char*}{data}}
583
584 Sets the image data without performing checks. The data given must have
585 the size (width*height*3) or results will be unexpected. Don't use this
586 method if you aren't sure you know what you are doing.
587
588 \membersection{wxImage::SetMask}\label{wximagesetmask}
589
590 \func{void}{SetMask}{\param{bool}{ hasMask = TRUE}}
591
592 Specifies whether there is a mask or not. The area of the mask is determined by the current mask colour.
593
594 \membersection{wxImage::SetMaskColour}\label{wximagesetmaskcolour}
595
596 \func{void}{SetMaskColour}{\param{unsigned char }{red}, \param{unsigned char }{blue}, \param{unsigned char }{green}}
597
598 Sets the mask colour for this image (and tells the image to use the mask).
599
600 \membersection{wxImage::SetRGB}\label{wximagesetrgb}
601
602 \func{void}{SetRGB}{\param{int }{x}, \param{int }{y}, \param{unsigned char }{red}, \param{unsigned char }{green}, \param{unsigned char }{blue}}
603
604 Sets the pixel at the given coordinate. This routine performs bounds-checks
605 for the coordinate so it can be considered a safe way to manipulate the
606 data, but in some cases this might be too slow so that the data will have to
607 be set directly. In that case you will have to get access to the image data
608 using the \helpref{GetData}{wximagegetdata} method.
609
610 \membersection{wxImage::operator $=$}
611
612 \func{wxImage\& }{operator $=$}{\param{const wxImage\& }{image}}
613
614 Assignment operator. This operator does not copy any data, but instead
615 passes a pointer to the data in {\it image} and increments a reference
616 counter. It is a fast operation.
617
618 \wxheading{Parameters}
619
620 \docparam{image}{Image to assign.}
621
622 \wxheading{Return value}
623
624 Returns 'this' object.
625
626 \membersection{wxImage::operator $==$}
627
628 \func{bool}{operator $==$}{\param{const wxImage\& }{image}}
629
630 Equality operator. This operator tests whether the internal data pointers are
631 equal (a fast test).
632
633 \wxheading{Parameters}
634
635 \docparam{image}{Image to compare with 'this'}
636
637 \wxheading{Return value}
638
639 Returns TRUE if the images were effectively equal, FALSE otherwise.
640
641 \membersection{wxImage::operator $!=$}
642
643 \func{bool}{operator $!=$}{\param{const wxImage\& }{image}}
644
645 Inequality operator. This operator tests whether the internal data pointers are
646 unequal (a fast test).
647
648 \wxheading{Parameters}
649
650 \docparam{image}{Image to compare with 'this'}
651
652 \wxheading{Return value}
653
654 Returns TRUE if the images were unequal, FALSE otherwise.
655
656 \section{\class{wxImageHandler}}\label{wximagehandler}
657
658 This is the base class for implementing image file loading/saving, and image creation from data.
659 It is used within wxImage and is not normally seen by the application.
660
661 If you wish to extend the capabilities of wxImage, derive a class from wxImageHandler
662 and add the handler using \helpref{wxImage::AddHandler}{wximageaddhandler} in your
663 application initialisation.
664
665 \wxheading{Note (Legal Issue)}
666
667 This software is based in part on the work of the Independent JPEG Group.
668
669 (Applies when wxWindows is linked with JPEG support. wxJPEGHandler uses libjpeg
670 created by IJG.)
671
672 \wxheading{Derived from}
673
674 \helpref{wxObject}{wxobject}
675
676 \wxheading{Include files}
677
678 <wx/image.h>
679
680 \wxheading{See also}
681
682 \helpref{wxImage}{wximage},
683 \helpref{wxInitAllImageHandlers}{wxinitallimagehandlers}
684
685 \latexignore{\rtfignore{\wxheading{Members}}}
686
687 \membersection{wxImageHandler::wxImageHandler}\label{wximagehandlerconstr}
688
689 \func{}{wxImageHandler}{\void}
690
691 Default constructor. In your own default constructor, initialise the members
692 m\_name, m\_extension and m\_type.
693
694 \membersection{wxImageHandler::\destruct{wxImageHandler}}
695
696 \func{}{\destruct{wxImageHandler}}{\void}
697
698 Destroys the wxImageHandler object.
699
700 \membersection{wxImageHandler::GetName}
701
702 \constfunc{wxString}{GetName}{\void}
703
704 Gets the name of this handler.
705
706 \membersection{wxImageHandler::GetExtension}
707
708 \constfunc{wxString}{GetExtension}{\void}
709
710 Gets the file extension associated with this handler.
711
712 \membersection{wxImageHandler::GetImageCount}\label{wximagehandlergetimagecount}
713
714 \func{int}{GetImageCount}{\param{wxInputStream\&}{ stream}}
715
716 If the image file contains more than one image and the image handler is capable
717 of retrieving these individually, this function will return the number of
718 available images.
719
720 \docparam{stream}{Opened input stream for reading image data. Currently, the stream must support seeking.}
721
722 \wxheading{Return value}
723
724 Number of available images. For most image handles, this defaults to 1.
725
726 \membersection{wxImageHandler::GetType}
727
728 \constfunc{long}{GetType}{\void}
729
730 Gets the image type associated with this handler.
731
732 \membersection{wxImageHandler::GetMimeType}
733
734 \constfunc{wxString}{GetMimeType}{\void}
735
736 Gets the MIME type associated with this handler.
737
738 \membersection{wxImageHandler::LoadFile}\label{wximagehandlerloadfile}
739
740 \func{bool}{LoadFile}{\param{wxImage* }{image}, \param{wxInputStream\&}{ stream}, \param{bool}{ verbose=TRUE}, \param{int}{ index=0}}
741
742 Loads a image from a stream, putting the resulting data into {\it image}. If the image file contains
743 more than one image and the image handler is capable of retrieving these individually, {\it index}
744 indicates which image to read from the stream.
745
746 \wxheading{Parameters}
747
748 \docparam{image}{The image object which is to be affected by this operation.}
749
750 \docparam{stream}{Opened input stream for reading image data.}
751
752 \docparam{verbose}{If set to TRUE, errors reported by the image handler will produce wxLogMessages.}
753
754 \docparam{index}{The index of the image in the file (starting from zero).}
755
756 \wxheading{Return value}
757
758 TRUE if the operation succeeded, FALSE otherwise.
759
760 \wxheading{See also}
761
762 \helpref{wxImage::LoadFile}{wximageloadfile},
763 \helpref{wxImage::SaveFile}{wximagesavefile},
764 \helpref{wxImageHandler::SaveFile}{wximagehandlersavefile}
765
766 \membersection{wxImageHandler::SaveFile}\label{wximagehandlersavefile}
767
768 \func{bool}{SaveFile}{\param{wxImage* }{image}, \param{wxOutputStream\& }{stream}}
769
770 Saves a image in the output stream.
771
772 \wxheading{Parameters}
773
774 \docparam{image}{The image object which is to be affected by this operation.}
775
776 \docparam{stream}{Opened output stream for writing the data.}
777
778 \wxheading{Return value}
779
780 TRUE if the operation succeeded, FALSE otherwise.
781
782 \wxheading{See also}
783
784 \helpref{wxImage::LoadFile}{wximageloadfile},
785 \helpref{wxImage::SaveFile}{wximagesavefile},
786 \helpref{wxImageHandler::LoadFile}{wximagehandlerloadfile}
787
788 \membersection{wxImageHandler::SetName}
789
790 \func{void}{SetName}{\param{const wxString\& }{name}}
791
792 Sets the handler name.
793
794 \wxheading{Parameters}
795
796 \docparam{name}{Handler name.}
797
798 \membersection{wxImageHandler::SetExtension}
799
800 \func{void}{SetExtension}{\param{const wxString\& }{extension}}
801
802 Sets the handler extension.
803
804 \wxheading{Parameters}
805
806 \docparam{extension}{Handler extension.}
807
808 \membersection{wxImageHandler::SetMimeType}\label{wximagehandlersetmimetype}
809
810 \func{void}{SetMimeType}{\param{const wxString\& }{mimetype}}
811
812 Sets the handler MIME type.
813
814 \wxheading{Parameters}
815
816 \docparam{mimename}{Handler MIME type.}
817
818 \membersection{wxImageHandler::SetType}
819
820 \func{void}{SetType}{\param{long }{type}}
821
822 Sets the handler type.
823
824 \wxheading{Parameters}
825
826 \docparam{name}{Handler type.}
827