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