src/common/imagjpeg.cpp

   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 )
 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) wxLogError(_("Couldn't load a JPEG image - probably file is corrupted."));
 173       jpeg_destroy_decompress(&cinfo);
 174       if (image->Ok()) image->Destroy();
 175       return FALSE;
 176     }
 177
 178     jpeg_create_decompress( &cinfo );
 179     jpeg_wxio_src( &cinfo, stream );
 180     jpeg_read_header( &cinfo, TRUE );
 181     cinfo.out_color_space = JCS_RGB;
 182     jpeg_start_decompress( &cinfo );
 183
 184     image->Create( cinfo.image_width, cinfo.image_height );
 185     if (!image->Ok()) {
 186         jpeg_finish_decompress( &cinfo );
 187         jpeg_destroy_decompress( &cinfo );
 188         return FALSE;
 189     }
 190     image->SetMask( FALSE );
 191     ptr = image->GetData();
 192     stride = cinfo.output_width * 3;
 193     tempbuf = (*cinfo.mem->alloc_sarray)
 194         ((j_common_ptr) &cinfo, JPOOL_IMAGE, stride, 1 );
 195
 196     while ( cinfo.output_scanline < cinfo.output_height ) {
 197         jpeg_read_scanlines( &cinfo, tempbuf, 1 );
 198         memcpy( ptr, tempbuf[0], stride );
 199         ptr += stride;
 200     }
 201     jpeg_finish_decompress( &cinfo );
 202     jpeg_destroy_decompress( &cinfo );
 203     return TRUE;
 204 }
 205
 206
 207
 208
 209
 210 typedef struct {
 211     struct jpeg_destination_mgr pub;
 212
 213     wxOutputStream *stream;
 214     JOCTET * buffer;
 215 } my_destination_mgr;
 216
 217 typedef my_destination_mgr * my_dest_ptr;
 218
 219 #define OUTPUT_BUF_SIZE  4096    /* choose an efficiently fwrite'able size */
 220
 221 METHODDEF(void) init_destination (j_compress_ptr cinfo)
 222 {
 223     my_dest_ptr dest = (my_dest_ptr) cinfo->dest;
 224
 225     /* Allocate the output buffer --- it will be released when done with image */
 226     dest->buffer = (JOCTET *)
 227         (*cinfo->mem->alloc_small) ((j_common_ptr) cinfo, JPOOL_IMAGE,
 228         OUTPUT_BUF_SIZE * sizeof(JOCTET));
 229     dest->pub.next_output_byte = dest->buffer;
 230     dest->pub.free_in_buffer = OUTPUT_BUF_SIZE;
 231 }
 232
 233 METHODDEF(boolean) empty_output_buffer (j_compress_ptr cinfo)
 234 {
 235     my_dest_ptr dest = (my_dest_ptr) cinfo->dest;
 236
 237     dest->stream->Write(dest->buffer, OUTPUT_BUF_SIZE);
 238     dest->pub.next_output_byte = dest->buffer;
 239     dest->pub.free_in_buffer = OUTPUT_BUF_SIZE;
 240     return TRUE;
 241 }
 242
 243 METHODDEF(void) term_destination (j_compress_ptr cinfo)
 244 {
 245     my_dest_ptr dest = (my_dest_ptr) cinfo->dest;
 246     size_t datacount = OUTPUT_BUF_SIZE - dest->pub.free_in_buffer;
 247     /* Write any data remaining in the buffer */
 248     if (datacount > 0)
 249         dest->stream->Write(dest->buffer, datacount);
 250 }
 251
 252 GLOBAL(void) jpeg_wxio_dest (j_compress_ptr cinfo, wxOutputStream& outfile)
 253 {
 254     my_dest_ptr dest;
 255
 256     if (cinfo->dest == NULL) {    /* first time for this JPEG object? */
 257         cinfo->dest = (struct jpeg_destination_mgr *)
 258             (*cinfo->mem->alloc_small) ((j_common_ptr) cinfo, JPOOL_PERMANENT,
 259             sizeof(my_destination_mgr));
 260     }
 261
 262     dest = (my_dest_ptr) cinfo->dest;
 263     dest->pub.init_destination = init_destination;
 264     dest->pub.empty_output_buffer = empty_output_buffer;
 265     dest->pub.term_destination = term_destination;
 266     dest->stream = &outfile;
 267 }
 268
 269 bool wxJPEGHandler::SaveFile( wxImage *image, wxOutputStream& stream, bool verbose )
 270 {
 271     struct jpeg_compress_struct cinfo;
 272     struct my_error_mgr jerr;
 273     JSAMPROW row_pointer[1];    /* pointer to JSAMPLE row[s] */
 274     JSAMPLE *image_buffer;
 275     int stride;                /* physical row width in image buffer */
 276
 277     cinfo.err = jpeg_std_error(&jerr.pub);
 278     jerr.pub.error_exit = my_error_exit;
 279
 280     if (!verbose) cinfo.err->output_message=NULL;
 281
 282     /* Establish the setjmp return context for my_error_exit to use. */
 283     if (setjmp(jerr.setjmp_buffer)) {
 284       /* If we get here, the JPEG code has signaled an error.
 285        * We need to clean up the JPEG object, close the input file, and return.
 286        */
 287       if (verbose) wxLogError(_("Couldn't save a JPEG image - probably file is corrupted."));
 288       jpeg_destroy_compress(&cinfo);
 289       return FALSE;
 290     }
 291
 292     jpeg_create_compress(&cinfo);
 293     jpeg_wxio_dest(&cinfo, stream);
 294
 295     cinfo.image_width = image->GetWidth();
 296     cinfo.image_height = image->GetHeight();
 297     cinfo.input_components = 3;
 298     cinfo.in_color_space = JCS_RGB;
 299     jpeg_set_defaults(&cinfo);
 300     jpeg_start_compress(&cinfo, TRUE);
 301
 302     stride = cinfo.image_width * 3;    /* JSAMPLEs per row in image_buffer */
 303     image_buffer = image->GetData();
 304     while (cinfo.next_scanline < cinfo.image_height) {
 305         row_pointer[0] = &image_buffer[cinfo.next_scanline * stride];
 306         jpeg_write_scanlines( &cinfo, row_pointer, 1 );
 307     }
 308     jpeg_finish_compress(&cinfo);
 309     jpeg_destroy_compress(&cinfo);
 310
 311     return TRUE;
 312 }
 313
 314
 315 bool wxJPEGHandler::DoCanRead( wxInputStream& stream )
 316 {
 317     unsigned char hdr[2];
 318
 319     stream.Read(&hdr, 2);
 320     stream.SeekI(-2, wxFromCurrent);
 321     return (hdr[0] == 0xFF && hdr[1] == 0xD8);
 322 }
 323
 324 #endif   // wxUSE_STREAMS
 325
 326 #endif   // wxUSE_LIBJPEG
 327
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