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