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1 /////////////////////////////////////////////////////////////////////////////
2 // Name: imagjpeg.cpp
3 // Purpose: wxImage JPEG handler
4 // Author: Vaclav Slavik
5 // RCS-ID: $Id$
6 // Copyright: (c) Vaclav Slavik
7 // Licence: wxWindows licence
8 /////////////////////////////////////////////////////////////////////////////
9
10 /*
11 We don't put pragma implement in this file because it is already present in
12 src/common/image.cpp
13 */
14
15 // For compilers that support precompilation, includes "wx.h".
16 #include "wx/wxprec.h"
17
18 #ifdef __BORLANDC__
19 #pragma hdrstop
20 #endif
21
22 #include "wx/defs.h"
23
24 #if wxUSE_LIBJPEG
25
26 #include "wx/image.h"
27 #include "wx/bitmap.h"
28 #include "wx/debug.h"
29 #include "wx/log.h"
30 #include "wx/app.h"
31 extern "C"
32 {
33 #include "jpeglib.h"
34 }
35 #include "wx/filefn.h"
36 #include "wx/wfstream.h"
37 #include "wx/intl.h"
38 #include "wx/module.h"
39
40 // For memcpy
41 #include <string.h>
42 // For JPEG library error handling
43 #include <setjmp.h>
44
45 #ifdef __SALFORDC__
46 #ifdef FAR
47 #undef FAR
48 #endif
49 #endif
50
51 #ifdef __WXMSW__
52 #include <windows.h>
53 #endif
54
55 //-----------------------------------------------------------------------------
56 // wxJPEGHandler
57 //-----------------------------------------------------------------------------
58
59 #if !USE_SHARED_LIBRARIES
60 IMPLEMENT_DYNAMIC_CLASS(wxJPEGHandler,wxImageHandler)
61 #endif
62
63 #if wxUSE_STREAMS
64
65 //------------- JPEG Data Source Manager
66
67 typedef struct {
68 struct jpeg_source_mgr pub; /* public fields */
69
70 JOCTET* buffer; /* start of buffer */
71 } my_source_mgr;
72
73 typedef my_source_mgr * my_src_ptr;
74
75 METHODDEF(void) my_init_source ( j_decompress_ptr WXUNUSED(cinfo) )
76 {
77 }
78
79 METHODDEF(boolean) my_fill_input_buffer ( j_decompress_ptr WXUNUSED(cinfo) )
80 {
81 return TRUE;
82 }
83
84 METHODDEF(void) my_skip_input_data ( j_decompress_ptr cinfo, long num_bytes )
85 {
86 my_src_ptr src = (my_src_ptr) cinfo->src;
87
88 src->pub.next_input_byte += (size_t) num_bytes;
89 src->pub.bytes_in_buffer -= (size_t) num_bytes;
90 }
91
92 METHODDEF(void) my_term_source ( j_decompress_ptr cinfo )
93 {
94 my_src_ptr src = (my_src_ptr) cinfo->src;
95
96 free (src->buffer);
97 }
98
99 void jpeg_wxio_src( j_decompress_ptr cinfo, wxInputStream& infile )
100 {
101 my_src_ptr src;
102
103 if (cinfo->src == NULL) { /* first time for this JPEG object? */
104 cinfo->src = (struct jpeg_source_mgr *)
105 (*cinfo->mem->alloc_small) ((j_common_ptr) cinfo, JPOOL_PERMANENT,
106 sizeof(my_source_mgr));
107 src = (my_src_ptr) cinfo->src;
108 }
109 src = (my_src_ptr) cinfo->src;
110 src->pub.bytes_in_buffer = infile.GetSize(); /* forces fill_input_buffer on first read */
111 src->buffer = (JOCTET *) malloc (infile.GetSize());
112 src->pub.next_input_byte = src->buffer; /* until buffer loaded */
113 infile.Read(src->buffer, infile.GetSize());
114
115 src->pub.init_source = my_init_source;
116 src->pub.fill_input_buffer = my_fill_input_buffer;
117 src->pub.skip_input_data = my_skip_input_data;
118 src->pub.resync_to_restart = jpeg_resync_to_restart; /* use default method */
119 src->pub.term_source = my_term_source;
120 }
121
122
123 // JPEG error manager:
124
125 struct my_error_mgr {
126 struct jpeg_error_mgr pub; /* "public" fields */
127
128 jmp_buf setjmp_buffer; /* for return to caller */
129 };
130
131 typedef struct my_error_mgr * my_error_ptr;
132
133 /*
134 * Here's the routine that will replace the standard error_exit method:
135 */
136
137 METHODDEF(void)
138 my_error_exit (j_common_ptr cinfo)
139 {
140 /* cinfo->err really points to a my_error_mgr struct, so coerce pointer */
141 my_error_ptr myerr = (my_error_ptr) cinfo->err;
142
143 /* Always display the message. */
144 /* We could postpone this until after returning, if we chose. */
145 if (cinfo->err->output_message) (*cinfo->err->output_message) (cinfo);
146
147 /* Return control to the setjmp point */
148 longjmp(myerr->setjmp_buffer, 1);
149 }
150
151
152
153 bool wxJPEGHandler::LoadFile( wxImage *image, wxInputStream& stream, bool verbose, int WXUNUSED(index) )
154 {
155 struct jpeg_decompress_struct cinfo;
156 struct my_error_mgr jerr;
157 JSAMPARRAY tempbuf;
158 unsigned char *ptr;
159 unsigned stride;
160
161 image->Destroy();
162 cinfo.err = jpeg_std_error( &jerr.pub );
163 jerr.pub.error_exit = my_error_exit;
164
165 if (!verbose) cinfo.err->output_message=NULL;
166
167 /* Establish the setjmp return context for my_error_exit to use. */
168 if (setjmp(jerr.setjmp_buffer)) {
169 /* If we get here, the JPEG code has signaled an error.
170 * We need to clean up the JPEG object, close the input file, and return.
171 */
172 if (verbose)
173 wxLogError(_("JPEG: Couldn't load - file is probably corrupted."));
174 jpeg_destroy_decompress(&cinfo);
175 if (image->Ok()) image->Destroy();
176 return FALSE;
177 }
178
179 jpeg_create_decompress( &cinfo );
180 jpeg_wxio_src( &cinfo, stream );
181 jpeg_read_header( &cinfo, TRUE );
182 cinfo.out_color_space = JCS_RGB;
183 jpeg_start_decompress( &cinfo );
184
185 image->Create( cinfo.image_width, cinfo.image_height );
186 if (!image->Ok()) {
187 jpeg_finish_decompress( &cinfo );
188 jpeg_destroy_decompress( &cinfo );
189 return FALSE;
190 }
191 image->SetMask( FALSE );
192 ptr = image->GetData();
193 stride = cinfo.output_width * 3;
194 tempbuf = (*cinfo.mem->alloc_sarray)
195 ((j_common_ptr) &cinfo, JPOOL_IMAGE, stride, 1 );
196
197 while ( cinfo.output_scanline < cinfo.output_height ) {
198 jpeg_read_scanlines( &cinfo, tempbuf, 1 );
199 memcpy( ptr, tempbuf[0], stride );
200 ptr += stride;
201 }
202 jpeg_finish_decompress( &cinfo );
203 jpeg_destroy_decompress( &cinfo );
204 return TRUE;
205 }
206
207
208
209
210
211 typedef struct {
212 struct jpeg_destination_mgr pub;
213
214 wxOutputStream *stream;
215 JOCTET * buffer;
216 } my_destination_mgr;
217
218 typedef my_destination_mgr * my_dest_ptr;
219
220 #define OUTPUT_BUF_SIZE 4096 /* choose an efficiently fwrite'able size */
221
222 METHODDEF(void) init_destination (j_compress_ptr cinfo)
223 {
224 my_dest_ptr dest = (my_dest_ptr) cinfo->dest;
225
226 /* Allocate the output buffer --- it will be released when done with image */
227 dest->buffer = (JOCTET *)
228 (*cinfo->mem->alloc_small) ((j_common_ptr) cinfo, JPOOL_IMAGE,
229 OUTPUT_BUF_SIZE * sizeof(JOCTET));
230 dest->pub.next_output_byte = dest->buffer;
231 dest->pub.free_in_buffer = OUTPUT_BUF_SIZE;
232 }
233
234 METHODDEF(boolean) empty_output_buffer (j_compress_ptr cinfo)
235 {
236 my_dest_ptr dest = (my_dest_ptr) cinfo->dest;
237
238 dest->stream->Write(dest->buffer, OUTPUT_BUF_SIZE);
239 dest->pub.next_output_byte = dest->buffer;
240 dest->pub.free_in_buffer = OUTPUT_BUF_SIZE;
241 return TRUE;
242 }
243
244 METHODDEF(void) term_destination (j_compress_ptr cinfo)
245 {
246 my_dest_ptr dest = (my_dest_ptr) cinfo->dest;
247 size_t datacount = OUTPUT_BUF_SIZE - dest->pub.free_in_buffer;
248 /* Write any data remaining in the buffer */
249 if (datacount > 0)
250 dest->stream->Write(dest->buffer, datacount);
251 }
252
253 GLOBAL(void) jpeg_wxio_dest (j_compress_ptr cinfo, wxOutputStream& outfile)
254 {
255 my_dest_ptr dest;
256
257 if (cinfo->dest == NULL) { /* first time for this JPEG object? */
258 cinfo->dest = (struct jpeg_destination_mgr *)
259 (*cinfo->mem->alloc_small) ((j_common_ptr) cinfo, JPOOL_PERMANENT,
260 sizeof(my_destination_mgr));
261 }
262
263 dest = (my_dest_ptr) cinfo->dest;
264 dest->pub.init_destination = init_destination;
265 dest->pub.empty_output_buffer = empty_output_buffer;
266 dest->pub.term_destination = term_destination;
267 dest->stream = &outfile;
268 }
269
270 bool wxJPEGHandler::SaveFile( wxImage *image, wxOutputStream& stream, bool verbose )
271 {
272 struct jpeg_compress_struct cinfo;
273 struct my_error_mgr jerr;
274 JSAMPROW row_pointer[1]; /* pointer to JSAMPLE row[s] */
275 JSAMPLE *image_buffer;
276 int stride; /* physical row width in image buffer */
277
278 cinfo.err = jpeg_std_error(&jerr.pub);
279 jerr.pub.error_exit = my_error_exit;
280
281 if (!verbose) cinfo.err->output_message=NULL;
282
283 /* Establish the setjmp return context for my_error_exit to use. */
284 if (setjmp(jerr.setjmp_buffer))
285 {
286 /* If we get here, the JPEG code has signaled an error.
287 * We need to clean up the JPEG object, close the input file, and return.
288 */
289 if (verbose)
290 wxLogError(_("JPEG: Couldn't save image."));
291 jpeg_destroy_compress(&cinfo);
292 return FALSE;
293 }
294
295 jpeg_create_compress(&cinfo);
296 jpeg_wxio_dest(&cinfo, stream);
297
298 cinfo.image_width = image->GetWidth();
299 cinfo.image_height = image->GetHeight();
300 cinfo.input_components = 3;
301 cinfo.in_color_space = JCS_RGB;
302 jpeg_set_defaults(&cinfo);
303 jpeg_start_compress(&cinfo, TRUE);
304
305 stride = cinfo.image_width * 3; /* JSAMPLEs per row in image_buffer */
306 image_buffer = image->GetData();
307 while (cinfo.next_scanline < cinfo.image_height) {
308 row_pointer[0] = &image_buffer[cinfo.next_scanline * stride];
309 jpeg_write_scanlines( &cinfo, row_pointer, 1 );
310 }
311 jpeg_finish_compress(&cinfo);
312 jpeg_destroy_compress(&cinfo);
313
314 return TRUE;
315 }
316
317
318 bool wxJPEGHandler::DoCanRead( wxInputStream& stream )
319 {
320 unsigned char hdr[2];
321
322 stream.Read(&hdr, 2);
323 stream.SeekI(-2, wxFromCurrent);
324 return (hdr[0] == 0xFF && hdr[1] == 0xD8);
325 }
326
327 #endif // wxUSE_STREAMS
328
329 #endif // wxUSE_LIBJPEG
330
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