1 /////////////////////////////////////////////////////////////////////////////
3 // Purpose: wxImage JPEG handler
4 // Author: Vaclav Slavik
6 // Copyright: (c) Vaclav Slavik
7 // Licence: wxWindows licence
8 /////////////////////////////////////////////////////////////////////////////
11 We don't put pragma implement in this file because it is already present in
15 // For compilers that support precompilation, includes "wx.h".
16 #include "wx/wxprec.h"
27 #include "wx/bitmap.h"
35 #include "wx/filefn.h"
36 #include "wx/wfstream.h"
38 #include "wx/module.h"
42 // For JPEG library error handling
55 //-----------------------------------------------------------------------------
57 //-----------------------------------------------------------------------------
59 #if !USE_SHARED_LIBRARIES
60 IMPLEMENT_DYNAMIC_CLASS(wxJPEGHandler
,wxImageHandler
)
65 //------------- JPEG Data Source Manager
68 struct jpeg_source_mgr pub
; /* public fields */
70 JOCTET
* buffer
; /* start of buffer */
73 typedef my_source_mgr
* my_src_ptr
;
75 METHODDEF(void) my_init_source ( j_decompress_ptr
WXUNUSED(cinfo
) )
79 METHODDEF(boolean
) my_fill_input_buffer ( j_decompress_ptr
WXUNUSED(cinfo
) )
84 METHODDEF(void) my_skip_input_data ( j_decompress_ptr cinfo
, long num_bytes
)
86 my_src_ptr src
= (my_src_ptr
) cinfo
->src
;
88 src
->pub
.next_input_byte
+= (size_t) num_bytes
;
89 src
->pub
.bytes_in_buffer
-= (size_t) num_bytes
;
92 METHODDEF(void) my_term_source ( j_decompress_ptr cinfo
)
94 my_src_ptr src
= (my_src_ptr
) cinfo
->src
;
99 void jpeg_wxio_src( j_decompress_ptr cinfo
, wxInputStream
& infile
)
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
;
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());
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
;
123 // JPEG error manager:
125 struct my_error_mgr
{
126 struct jpeg_error_mgr pub
; /* "public" fields */
128 jmp_buf setjmp_buffer
; /* for return to caller */
131 typedef struct my_error_mgr
* my_error_ptr
;
134 * Here's the routine that will replace the standard error_exit method:
138 my_error_exit (j_common_ptr cinfo
)
140 /* cinfo->err really points to a my_error_mgr struct, so coerce pointer */
141 my_error_ptr myerr
= (my_error_ptr
) cinfo
->err
;
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
);
147 /* Return control to the setjmp point */
148 longjmp(myerr
->setjmp_buffer
, 1);
153 bool wxJPEGHandler::LoadFile( wxImage
*image
, wxInputStream
& stream
, bool verbose
, int WXUNUSED(index
) )
155 struct jpeg_decompress_struct cinfo
;
156 struct my_error_mgr jerr
;
162 cinfo
.err
= jpeg_std_error( &jerr
.pub
);
163 jerr
.pub
.error_exit
= my_error_exit
;
165 if (!verbose
) cinfo
.err
->output_message
=NULL
;
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.
173 wxLogError(_("JPEG: Couldn't load - file is probably corrupted."));
174 jpeg_destroy_decompress(&cinfo
);
175 if (image
->Ok()) image
->Destroy();
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
);
185 image
->Create( cinfo
.image_width
, cinfo
.image_height
);
187 jpeg_finish_decompress( &cinfo
);
188 jpeg_destroy_decompress( &cinfo
);
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 );
197 while ( cinfo
.output_scanline
< cinfo
.output_height
) {
198 jpeg_read_scanlines( &cinfo
, tempbuf
, 1 );
199 memcpy( ptr
, tempbuf
[0], stride
);
202 jpeg_finish_decompress( &cinfo
);
203 jpeg_destroy_decompress( &cinfo
);
212 struct jpeg_destination_mgr pub
;
214 wxOutputStream
*stream
;
216 } my_destination_mgr
;
218 typedef my_destination_mgr
* my_dest_ptr
;
220 #define OUTPUT_BUF_SIZE 4096 /* choose an efficiently fwrite'able size */
222 METHODDEF(void) init_destination (j_compress_ptr cinfo
)
224 my_dest_ptr dest
= (my_dest_ptr
) cinfo
->dest
;
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
;
234 METHODDEF(boolean
) empty_output_buffer (j_compress_ptr cinfo
)
236 my_dest_ptr dest
= (my_dest_ptr
) cinfo
->dest
;
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
;
244 METHODDEF(void) term_destination (j_compress_ptr cinfo
)
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 */
250 dest
->stream
->Write(dest
->buffer
, datacount
);
253 GLOBAL(void) jpeg_wxio_dest (j_compress_ptr cinfo
, wxOutputStream
& outfile
)
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
));
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
;
270 bool wxJPEGHandler::SaveFile( wxImage
*image
, wxOutputStream
& stream
, bool verbose
)
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 */
278 cinfo
.err
= jpeg_std_error(&jerr
.pub
);
279 jerr
.pub
.error_exit
= my_error_exit
;
281 if (!verbose
) cinfo
.err
->output_message
=NULL
;
283 /* Establish the setjmp return context for my_error_exit to use. */
284 if (setjmp(jerr
.setjmp_buffer
))
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.
290 wxLogError(_("JPEG: Couldn't save image."));
291 jpeg_destroy_compress(&cinfo
);
295 jpeg_create_compress(&cinfo
);
296 jpeg_wxio_dest(&cinfo
, stream
);
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
);
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 );
311 jpeg_finish_compress(&cinfo
);
312 jpeg_destroy_compress(&cinfo
);
318 bool wxJPEGHandler::DoCanRead( wxInputStream
& stream
)
320 unsigned char hdr
[2];
322 stream
.Read(&hdr
, 2);
323 stream
.SeekI(-2, wxFromCurrent
);
324 return (hdr
[0] == 0xFF && hdr
[1] == 0xD8);
327 #endif // wxUSE_STREAMS
329 #endif // wxUSE_LIBJPEG