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e9c4b1a2 | 1 | ///////////////////////////////////////////////////////////////////////////// |
6d3d756a | 2 | // Name: src/common/imagjpeg.cpp |
e9c4b1a2 | 3 | // Purpose: wxImage JPEG handler |
b59ff3c9 | 4 | // Author: Vaclav Slavik |
e9c4b1a2 | 5 | // RCS-ID: $Id$ |
b59ff3c9 | 6 | // Copyright: (c) Vaclav Slavik |
65571936 | 7 | // Licence: wxWindows licence |
e9c4b1a2 JS |
8 | ///////////////////////////////////////////////////////////////////////////// |
9 | ||
e9c4b1a2 JS |
10 | // For compilers that support precompilation, includes "wx.h". |
11 | #include "wx/wxprec.h" | |
12 | ||
13 | #ifdef __BORLANDC__ | |
88a7a4e1 | 14 | #pragma hdrstop |
e9c4b1a2 JS |
15 | #endif |
16 | ||
c96ea657 | 17 | #if wxUSE_IMAGE && wxUSE_LIBJPEG |
ce4169a4 | 18 | |
88a7a4e1 WS |
19 | #include "wx/imagjpeg.h" |
20 | ||
8898456d WS |
21 | #ifndef WX_PRECOMP |
22 | #include "wx/log.h" | |
23 | #include "wx/app.h" | |
88a7a4e1 | 24 | #include "wx/intl.h" |
0bca0373 | 25 | #include "wx/bitmap.h" |
02761f6c | 26 | #include "wx/module.h" |
8898456d WS |
27 | #endif |
28 | ||
a4cc2d09 MW |
29 | // A hack based on one from tif_jpeg.c to overcome the problem on Windows |
30 | // of rpcndr.h defining boolean with a different type to the jpeg headers. | |
31 | // | |
32 | // This hack is only necessary for an external jpeg library, the builtin one | |
33 | // usually used on Windows doesn't use the type boolean, so always works. | |
34 | // | |
90eaf433 | 35 | #ifdef wxHACK_BOOLEAN |
a4cc2d09 | 36 | #define HAVE_BOOLEAN |
90eaf433 | 37 | #define boolean wxHACK_BOOLEAN |
a4cc2d09 MW |
38 | #endif |
39 | ||
995612e2 VZ |
40 | extern "C" |
41 | { | |
cd2a4e16 JS |
42 | #if defined(__WXMSW__) |
43 | #define XMD_H | |
44 | #endif | |
995612e2 | 45 | #include "jpeglib.h" |
e9c4b1a2 | 46 | } |
cb69afe0 | 47 | |
e604ac79 MW |
48 | #ifndef HAVE_WXJPEG_BOOLEAN |
49 | typedef boolean wxjpeg_boolean; | |
50 | #endif | |
51 | ||
e9c4b1a2 JS |
52 | #include "wx/filefn.h" |
53 | #include "wx/wfstream.h" | |
e9c4b1a2 JS |
54 | |
55 | // For memcpy | |
56 | #include <string.h> | |
b59ff3c9 VS |
57 | // For JPEG library error handling |
58 | #include <setjmp.h> | |
e9c4b1a2 JS |
59 | |
60 | #ifdef __SALFORDC__ | |
e9c4b1a2 JS |
61 | #undef FAR |
62 | #endif | |
e9c4b1a2 | 63 | |
d7c42914 VZ |
64 | // ---------------------------------------------------------------------------- |
65 | // types | |
66 | // ---------------------------------------------------------------------------- | |
67 | ||
68 | // the standard definition of METHODDEF(type) from jmorecfg.h is "static type" | |
69 | // which means that we can't declare the method functions as extern "C" - the | |
70 | // compiler (rightfully) complains about the multiple storage classes in | |
71 | // declaration | |
72 | // | |
73 | // so we only add extern "C" when using our own, modified, jmorecfg.h - and use | |
74 | // whatever we have in the system headers if this is what we use hoping that it | |
75 | // should be ok (can't do anything else) | |
76 | #ifdef JPEG_METHOD_LINKAGE | |
77 | #define CPP_METHODDEF(type) extern "C" METHODDEF(type) | |
78 | #else // not using our jmorecfg.h header | |
79 | #define CPP_METHODDEF(type) METHODDEF(type) | |
80 | #endif | |
90350682 | 81 | |
e9c4b1a2 JS |
82 | //----------------------------------------------------------------------------- |
83 | // wxJPEGHandler | |
84 | //----------------------------------------------------------------------------- | |
85 | ||
e9c4b1a2 | 86 | IMPLEMENT_DYNAMIC_CLASS(wxJPEGHandler,wxImageHandler) |
e9c4b1a2 | 87 | |
9ab6ee85 GRG |
88 | #if wxUSE_STREAMS |
89 | ||
e9c4b1a2 JS |
90 | //------------- JPEG Data Source Manager |
91 | ||
1aaaa712 VS |
92 | #define JPEG_IO_BUFFER_SIZE 2048 |
93 | ||
e9c4b1a2 JS |
94 | typedef struct { |
95 | struct jpeg_source_mgr pub; /* public fields */ | |
995612e2 | 96 | |
e9c4b1a2 | 97 | JOCTET* buffer; /* start of buffer */ |
1aaaa712 | 98 | wxInputStream *stream; |
e9b964cf | 99 | } wx_source_mgr; |
e9c4b1a2 | 100 | |
e9b964cf | 101 | typedef wx_source_mgr * wx_src_ptr; |
e9c4b1a2 | 102 | |
e9b964cf | 103 | CPP_METHODDEF(void) wx_init_source ( j_decompress_ptr WXUNUSED(cinfo) ) |
e9c4b1a2 JS |
104 | { |
105 | } | |
106 | ||
e604ac79 | 107 | CPP_METHODDEF(wxjpeg_boolean) wx_fill_input_buffer ( j_decompress_ptr cinfo ) |
e9c4b1a2 | 108 | { |
e9b964cf | 109 | wx_src_ptr src = (wx_src_ptr) cinfo->src; |
1aaaa712 VS |
110 | |
111 | src->pub.next_input_byte = src->buffer; | |
112 | src->pub.bytes_in_buffer = src->stream->Read(src->buffer, JPEG_IO_BUFFER_SIZE).LastRead(); | |
113 | ||
114 | if (src->pub.bytes_in_buffer == 0) // check for end-of-stream | |
115 | { | |
116 | // Insert a fake EOI marker | |
117 | src->buffer[0] = 0xFF; | |
118 | src->buffer[1] = JPEG_EOI; | |
119 | src->pub.bytes_in_buffer = 2; | |
120 | } | |
e9c4b1a2 JS |
121 | return TRUE; |
122 | } | |
123 | ||
e9b964cf | 124 | CPP_METHODDEF(void) wx_skip_input_data ( j_decompress_ptr cinfo, long num_bytes ) |
e9c4b1a2 | 125 | { |
1aaaa712 VS |
126 | if (num_bytes > 0) |
127 | { | |
e9b964cf | 128 | wx_src_ptr src = (wx_src_ptr) cinfo->src; |
1aaaa712 | 129 | |
33ac7e6f | 130 | while (num_bytes > (long)src->pub.bytes_in_buffer) |
1aaaa712 VS |
131 | { |
132 | num_bytes -= (long) src->pub.bytes_in_buffer; | |
133 | src->pub.fill_input_buffer(cinfo); | |
134 | } | |
135 | src->pub.next_input_byte += (size_t) num_bytes; | |
136 | src->pub.bytes_in_buffer -= (size_t) num_bytes; | |
137 | } | |
e9c4b1a2 JS |
138 | } |
139 | ||
e9b964cf | 140 | CPP_METHODDEF(void) wx_term_source ( j_decompress_ptr cinfo ) |
e9c4b1a2 | 141 | { |
e9b964cf | 142 | wx_src_ptr src = (wx_src_ptr) cinfo->src; |
995612e2 | 143 | |
1aaaa712 | 144 | if (src->pub.bytes_in_buffer > 0) |
3ca6a5f0 | 145 | src->stream->SeekI(-(long)src->pub.bytes_in_buffer, wxFromCurrent); |
1aaaa712 | 146 | delete[] src->buffer; |
e9c4b1a2 JS |
147 | } |
148 | ||
e9c4b1a2 | 149 | |
b59ff3c9 VS |
150 | // JPEG error manager: |
151 | ||
e9b964cf | 152 | struct wx_error_mgr { |
995612e2 | 153 | struct jpeg_error_mgr pub; /* "public" fields */ |
b59ff3c9 | 154 | |
995612e2 | 155 | jmp_buf setjmp_buffer; /* for return to caller */ |
b59ff3c9 VS |
156 | }; |
157 | ||
e9b964cf | 158 | typedef struct wx_error_mgr * wx_error_ptr; |
b59ff3c9 VS |
159 | |
160 | /* | |
161 | * Here's the routine that will replace the standard error_exit method: | |
162 | */ | |
163 | ||
e9b964cf | 164 | CPP_METHODDEF(void) wx_error_exit (j_common_ptr cinfo) |
b59ff3c9 | 165 | { |
e9b964cf VS |
166 | /* cinfo->err really points to a wx_error_mgr struct, so coerce pointer */ |
167 | wx_error_ptr myerr = (wx_error_ptr) cinfo->err; | |
b59ff3c9 VS |
168 | |
169 | /* Always display the message. */ | |
170 | /* We could postpone this until after returning, if we chose. */ | |
ef25e5a4 | 171 | (*cinfo->err->output_message) (cinfo); |
b59ff3c9 VS |
172 | |
173 | /* Return control to the setjmp point */ | |
174 | longjmp(myerr->setjmp_buffer, 1); | |
175 | } | |
176 | ||
ef25e5a4 VZ |
177 | /* |
178 | * This will replace the standard output_message method when the user | |
179 | * wants us to be silent (verbose==false). We must have such method instead of | |
180 | * simply using NULL for cinfo->err->output_message because it's called | |
181 | * unconditionally from within libjpeg when there's "garbage input". | |
182 | */ | |
183 | CPP_METHODDEF(void) wx_ignore_message (j_common_ptr WXUNUSED(cinfo)) | |
184 | { | |
185 | } | |
186 | ||
e9b964cf | 187 | void wx_jpeg_io_src( j_decompress_ptr cinfo, wxInputStream& infile ) |
90350682 | 188 | { |
e9b964cf | 189 | wx_src_ptr src; |
90350682 VZ |
190 | |
191 | if (cinfo->src == NULL) { /* first time for this JPEG object? */ | |
192 | cinfo->src = (struct jpeg_source_mgr *) | |
193 | (*cinfo->mem->alloc_small) ((j_common_ptr) cinfo, JPOOL_PERMANENT, | |
e9b964cf | 194 | sizeof(wx_source_mgr)); |
90350682 | 195 | } |
e9b964cf | 196 | src = (wx_src_ptr) cinfo->src; |
90350682 VZ |
197 | src->pub.bytes_in_buffer = 0; /* forces fill_input_buffer on first read */ |
198 | src->buffer = new JOCTET[JPEG_IO_BUFFER_SIZE]; | |
199 | src->pub.next_input_byte = NULL; /* until buffer loaded */ | |
200 | src->stream = &infile; | |
201 | ||
e9b964cf VS |
202 | src->pub.init_source = wx_init_source; |
203 | src->pub.fill_input_buffer = wx_fill_input_buffer; | |
204 | src->pub.skip_input_data = wx_skip_input_data; | |
90350682 | 205 | src->pub.resync_to_restart = jpeg_resync_to_restart; /* use default method */ |
e9b964cf | 206 | src->pub.term_source = wx_term_source; |
90350682 VZ |
207 | } |
208 | ||
234fedd2 VZ |
209 | static inline void wx_cmyk_to_rgb(unsigned char* rgb, const unsigned char* cmyk) |
210 | { | |
211 | register int k = 255 - cmyk[3]; | |
212 | register int k2 = cmyk[3]; | |
213 | register int c; | |
214 | ||
215 | c = k + k2 * (255 - cmyk[0]) / 255; | |
ff7d9066 | 216 | rgb[0] = (unsigned char)((c > 255) ? 0 : (255 - c)); |
234fedd2 VZ |
217 | |
218 | c = k + k2 * (255 - cmyk[1]) / 255; | |
ff7d9066 | 219 | rgb[1] = (unsigned char)((c > 255) ? 0 : (255 - c)); |
234fedd2 VZ |
220 | |
221 | c = k + k2 * (255 - cmyk[2]) / 255; | |
ff7d9066 | 222 | rgb[2] = (unsigned char)((c > 255) ? 0 : (255 - c)); |
234fedd2 | 223 | } |
90350682 | 224 | |
3ca6a5f0 BP |
225 | // temporarily disable the warning C4611 (interaction between '_setjmp' and |
226 | // C++ object destruction is non-portable) - I don't see any dtors here | |
227 | #ifdef __VISUALC__ | |
228 | #pragma warning(disable:4611) | |
229 | #endif /* VC++ */ | |
e9c4b1a2 | 230 | |
700ec454 | 231 | bool wxJPEGHandler::LoadFile( wxImage *image, wxInputStream& stream, bool verbose, int WXUNUSED(index) ) |
e9c4b1a2 JS |
232 | { |
233 | struct jpeg_decompress_struct cinfo; | |
e9b964cf | 234 | struct wx_error_mgr jerr; |
e9c4b1a2 | 235 | unsigned char *ptr; |
995612e2 | 236 | |
e9c4b1a2 | 237 | image->Destroy(); |
b59ff3c9 | 238 | cinfo.err = jpeg_std_error( &jerr.pub ); |
e9b964cf | 239 | jerr.pub.error_exit = wx_error_exit; |
b59ff3c9 | 240 | |
ef25e5a4 VZ |
241 | if (!verbose) |
242 | cinfo.err->output_message = wx_ignore_message; | |
deb2fec0 | 243 | |
e9b964cf | 244 | /* Establish the setjmp return context for wx_error_exit to use. */ |
b59ff3c9 VS |
245 | if (setjmp(jerr.setjmp_buffer)) { |
246 | /* If we get here, the JPEG code has signaled an error. | |
247 | * We need to clean up the JPEG object, close the input file, and return. | |
248 | */ | |
33ac7e6f | 249 | if (verbose) |
58c837a4 | 250 | wxLogError(_("JPEG: Couldn't load - file is probably corrupted.")); |
192644bf | 251 | (cinfo.src->term_source)(&cinfo); |
b59ff3c9 VS |
252 | jpeg_destroy_decompress(&cinfo); |
253 | if (image->Ok()) image->Destroy(); | |
7beb59f3 | 254 | return false; |
b59ff3c9 VS |
255 | } |
256 | ||
e9c4b1a2 | 257 | jpeg_create_decompress( &cinfo ); |
e9b964cf | 258 | wx_jpeg_io_src( &cinfo, stream ); |
e9c4b1a2 | 259 | jpeg_read_header( &cinfo, TRUE ); |
234fedd2 VZ |
260 | |
261 | int bytesPerPixel; | |
262 | if ((cinfo.out_color_space == JCS_CMYK) || (cinfo.out_color_space == JCS_YCCK)) | |
263 | { | |
264 | cinfo.out_color_space = JCS_CMYK; | |
265 | bytesPerPixel = 4; | |
266 | } | |
267 | else // all the rest is treated as RGB | |
268 | { | |
269 | cinfo.out_color_space = JCS_RGB; | |
270 | bytesPerPixel = 3; | |
271 | } | |
272 | ||
e9c4b1a2 | 273 | jpeg_start_decompress( &cinfo ); |
995612e2 | 274 | |
e9c4b1a2 JS |
275 | image->Create( cinfo.image_width, cinfo.image_height ); |
276 | if (!image->Ok()) { | |
277 | jpeg_finish_decompress( &cinfo ); | |
278 | jpeg_destroy_decompress( &cinfo ); | |
7beb59f3 | 279 | return false; |
e9c4b1a2 | 280 | } |
7beb59f3 | 281 | image->SetMask( false ); |
e9c4b1a2 | 282 | ptr = image->GetData(); |
995612e2 | 283 | |
234fedd2 VZ |
284 | unsigned stride = cinfo.output_width * bytesPerPixel; |
285 | JSAMPARRAY tempbuf = (*cinfo.mem->alloc_sarray) | |
286 | ((j_common_ptr) &cinfo, JPOOL_IMAGE, stride, 1 ); | |
287 | ||
288 | while ( cinfo.output_scanline < cinfo.output_height ) | |
289 | { | |
e9c4b1a2 | 290 | jpeg_read_scanlines( &cinfo, tempbuf, 1 ); |
234fedd2 VZ |
291 | if (cinfo.out_color_space == JCS_RGB) |
292 | { | |
293 | memcpy( ptr, tempbuf[0], stride ); | |
294 | ptr += stride; | |
295 | } | |
296 | else // CMYK | |
297 | { | |
298 | const unsigned char* inptr = (const unsigned char*) tempbuf[0]; | |
299 | for (size_t i = 0; i < cinfo.output_width; i++) | |
300 | { | |
301 | wx_cmyk_to_rgb(ptr, inptr); | |
302 | ptr += 3; | |
303 | inptr += 4; | |
304 | } | |
305 | } | |
e9c4b1a2 | 306 | } |
234fedd2 | 307 | |
e9c4b1a2 JS |
308 | jpeg_finish_decompress( &cinfo ); |
309 | jpeg_destroy_decompress( &cinfo ); | |
7beb59f3 | 310 | return true; |
e9c4b1a2 JS |
311 | } |
312 | ||
e9c4b1a2 JS |
313 | typedef struct { |
314 | struct jpeg_destination_mgr pub; | |
995612e2 | 315 | |
e9c4b1a2 JS |
316 | wxOutputStream *stream; |
317 | JOCTET * buffer; | |
e9b964cf | 318 | } wx_destination_mgr; |
e9c4b1a2 | 319 | |
e9b964cf | 320 | typedef wx_destination_mgr * wx_dest_ptr; |
e9c4b1a2 | 321 | |
995612e2 | 322 | #define OUTPUT_BUF_SIZE 4096 /* choose an efficiently fwrite'able size */ |
e9c4b1a2 | 323 | |
e9b964cf | 324 | CPP_METHODDEF(void) wx_init_destination (j_compress_ptr cinfo) |
e9c4b1a2 | 325 | { |
e9b964cf | 326 | wx_dest_ptr dest = (wx_dest_ptr) cinfo->dest; |
995612e2 | 327 | |
e9c4b1a2 JS |
328 | /* Allocate the output buffer --- it will be released when done with image */ |
329 | dest->buffer = (JOCTET *) | |
330 | (*cinfo->mem->alloc_small) ((j_common_ptr) cinfo, JPOOL_IMAGE, | |
331 | OUTPUT_BUF_SIZE * sizeof(JOCTET)); | |
332 | dest->pub.next_output_byte = dest->buffer; | |
333 | dest->pub.free_in_buffer = OUTPUT_BUF_SIZE; | |
334 | } | |
335 | ||
e604ac79 | 336 | CPP_METHODDEF(wxjpeg_boolean) wx_empty_output_buffer (j_compress_ptr cinfo) |
e9c4b1a2 | 337 | { |
e9b964cf | 338 | wx_dest_ptr dest = (wx_dest_ptr) cinfo->dest; |
995612e2 | 339 | |
e9c4b1a2 JS |
340 | dest->stream->Write(dest->buffer, OUTPUT_BUF_SIZE); |
341 | dest->pub.next_output_byte = dest->buffer; | |
342 | dest->pub.free_in_buffer = OUTPUT_BUF_SIZE; | |
343 | return TRUE; | |
344 | } | |
345 | ||
e9b964cf | 346 | CPP_METHODDEF(void) wx_term_destination (j_compress_ptr cinfo) |
e9c4b1a2 | 347 | { |
e9b964cf | 348 | wx_dest_ptr dest = (wx_dest_ptr) cinfo->dest; |
e9c4b1a2 JS |
349 | size_t datacount = OUTPUT_BUF_SIZE - dest->pub.free_in_buffer; |
350 | /* Write any data remaining in the buffer */ | |
351 | if (datacount > 0) | |
352 | dest->stream->Write(dest->buffer, datacount); | |
353 | } | |
354 | ||
e9b964cf | 355 | GLOBAL(void) wx_jpeg_io_dest (j_compress_ptr cinfo, wxOutputStream& outfile) |
e9c4b1a2 | 356 | { |
e9b964cf | 357 | wx_dest_ptr dest; |
995612e2 VZ |
358 | |
359 | if (cinfo->dest == NULL) { /* first time for this JPEG object? */ | |
e9c4b1a2 JS |
360 | cinfo->dest = (struct jpeg_destination_mgr *) |
361 | (*cinfo->mem->alloc_small) ((j_common_ptr) cinfo, JPOOL_PERMANENT, | |
e9b964cf | 362 | sizeof(wx_destination_mgr)); |
e9c4b1a2 | 363 | } |
995612e2 | 364 | |
e9b964cf VS |
365 | dest = (wx_dest_ptr) cinfo->dest; |
366 | dest->pub.init_destination = wx_init_destination; | |
367 | dest->pub.empty_output_buffer = wx_empty_output_buffer; | |
368 | dest->pub.term_destination = wx_term_destination; | |
e9c4b1a2 JS |
369 | dest->stream = &outfile; |
370 | } | |
371 | ||
deb2fec0 | 372 | bool wxJPEGHandler::SaveFile( wxImage *image, wxOutputStream& stream, bool verbose ) |
e9c4b1a2 JS |
373 | { |
374 | struct jpeg_compress_struct cinfo; | |
e9b964cf | 375 | struct wx_error_mgr jerr; |
995612e2 | 376 | JSAMPROW row_pointer[1]; /* pointer to JSAMPLE row[s] */ |
e9c4b1a2 | 377 | JSAMPLE *image_buffer; |
995612e2 VZ |
378 | int stride; /* physical row width in image buffer */ |
379 | ||
b59ff3c9 | 380 | cinfo.err = jpeg_std_error(&jerr.pub); |
e9b964cf | 381 | jerr.pub.error_exit = wx_error_exit; |
b59ff3c9 | 382 | |
ef25e5a4 VZ |
383 | if (!verbose) |
384 | cinfo.err->output_message = wx_ignore_message; | |
deb2fec0 | 385 | |
e9b964cf | 386 | /* Establish the setjmp return context for wx_error_exit to use. */ |
33ac7e6f | 387 | if (setjmp(jerr.setjmp_buffer)) |
58c837a4 RR |
388 | { |
389 | /* If we get here, the JPEG code has signaled an error. | |
390 | * We need to clean up the JPEG object, close the input file, and return. | |
391 | */ | |
33ac7e6f | 392 | if (verbose) |
58c837a4 RR |
393 | wxLogError(_("JPEG: Couldn't save image.")); |
394 | jpeg_destroy_compress(&cinfo); | |
7beb59f3 | 395 | return false; |
b59ff3c9 VS |
396 | } |
397 | ||
e9c4b1a2 | 398 | jpeg_create_compress(&cinfo); |
e9b964cf | 399 | wx_jpeg_io_dest(&cinfo, stream); |
995612e2 | 400 | |
e9c4b1a2 JS |
401 | cinfo.image_width = image->GetWidth(); |
402 | cinfo.image_height = image->GetHeight(); | |
403 | cinfo.input_components = 3; | |
404 | cinfo.in_color_space = JCS_RGB; | |
405 | jpeg_set_defaults(&cinfo); | |
5e5437e0 JS |
406 | |
407 | // TODO: 3rd parameter is force_baseline, what value should this be? | |
408 | // Code says: "If force_baseline is TRUE, the computed quantization table entries | |
409 | // are limited to 1..255 for JPEG baseline compatibility." | |
410 | // 'Quality' is a number between 0 (terrible) and 100 (very good). | |
411 | // The default (in jcparam.c, jpeg_set_defaults) is 75, | |
412 | // and force_baseline is TRUE. | |
9a679df6 JS |
413 | if (image->HasOption(wxIMAGE_OPTION_QUALITY)) |
414 | jpeg_set_quality(&cinfo, image->GetOptionInt(wxIMAGE_OPTION_QUALITY), TRUE); | |
5e5437e0 | 415 | |
fe9308c6 | 416 | // set the resolution fields in the output file |
361f4288 VZ |
417 | int resX, resY; |
418 | wxImageResolution res = GetResolutionFromOptions(*image, &resX, &resY); | |
419 | if ( res != wxIMAGE_RESOLUTION_NONE ) | |
fe9308c6 VZ |
420 | { |
421 | cinfo.X_density = resX; | |
422 | cinfo.Y_density = resY; | |
89d38f8c | 423 | |
361f4288 VZ |
424 | // it so happens that wxIMAGE_RESOLUTION_INCHES/CM values are the same |
425 | // ones as used by libjpeg, so we can assign them directly | |
426 | cinfo.density_unit = res; | |
89d38f8c VS |
427 | } |
428 | ||
e9c4b1a2 | 429 | jpeg_start_compress(&cinfo, TRUE); |
995612e2 VZ |
430 | |
431 | stride = cinfo.image_width * 3; /* JSAMPLEs per row in image_buffer */ | |
e9c4b1a2 JS |
432 | image_buffer = image->GetData(); |
433 | while (cinfo.next_scanline < cinfo.image_height) { | |
434 | row_pointer[0] = &image_buffer[cinfo.next_scanline * stride]; | |
435 | jpeg_write_scanlines( &cinfo, row_pointer, 1 ); | |
436 | } | |
437 | jpeg_finish_compress(&cinfo); | |
438 | jpeg_destroy_compress(&cinfo); | |
995612e2 | 439 | |
7beb59f3 | 440 | return true; |
e9c4b1a2 | 441 | } |
e9c4b1a2 | 442 | |
3ca6a5f0 BP |
443 | #ifdef __VISUALC__ |
444 | #pragma warning(default:4611) | |
445 | #endif /* VC++ */ | |
0828c087 | 446 | |
995612e2 | 447 | bool wxJPEGHandler::DoCanRead( wxInputStream& stream ) |
0828c087 VS |
448 | { |
449 | unsigned char hdr[2]; | |
995612e2 | 450 | |
79fa2374 | 451 | if ( !stream.Read(hdr, WXSIZEOF(hdr)) ) |
7beb59f3 | 452 | return false; |
79fa2374 | 453 | |
79fa2374 | 454 | return hdr[0] == 0xFF && hdr[1] == 0xD8; |
0828c087 VS |
455 | } |
456 | ||
9ab6ee85 GRG |
457 | #endif // wxUSE_STREAMS |
458 | ||
459 | #endif // wxUSE_LIBJPEG |