1 ///////////////////////////////////////////////////////////////////////////// 
   2 // Name:        src/common/imagjpeg.cpp 
   3 // Purpose:     wxImage JPEG handler 
   4 // Author:      Vaclav Slavik 
   6 // Copyright:   (c) Vaclav Slavik 
   7 // Licence:     wxWindows licence 
   8 ///////////////////////////////////////////////////////////////////////////// 
  10 // For compilers that support precompilation, includes "wx.h". 
  11 #include "wx/wxprec.h" 
  17 #if wxUSE_IMAGE && wxUSE_LIBJPEG 
  19 #include "wx/imagjpeg.h" 
  25     #include "wx/bitmap.h" 
  26     #include "wx/module.h" 
  29 // A hack based on one from tif_jpeg.c to overcome the problem on Windows 
  30 // of rpcndr.h defining boolean with a different type to the jpeg headers. 
  32 // This hack is only necessary for an external jpeg library, the builtin one 
  33 // usually used on Windows doesn't use the type boolean, so always works. 
  37     #define boolean wxHACK_BOOLEAN 
  42     #if defined(__WXMSW__) 
  48 #ifndef HAVE_WXJPEG_BOOLEAN 
  49 typedef boolean wxjpeg_boolean
; 
  52 #include "wx/filefn.h" 
  53 #include "wx/wfstream.h" 
  57 // For JPEG library error handling 
  64 // ---------------------------------------------------------------------------- 
  66 // ---------------------------------------------------------------------------- 
  68 // the standard definition of METHODDEF(type) from jmorecfg.h is "static type" 
  69 // which means that we can't declare the method functions as extern "C" - the 
  70 // compiler (rightfully) complains about the multiple storage classes in 
  73 // so we only add extern "C" when using our own, modified, jmorecfg.h - and use 
  74 // whatever we have in the system headers if this is what we use hoping that it 
  75 // should be ok (can't do anything else) 
  76 #ifdef JPEG_METHOD_LINKAGE 
  77     #define CPP_METHODDEF(type) extern "C" METHODDEF(type) 
  78 #else // not using our jmorecfg.h header 
  79     #define CPP_METHODDEF(type) METHODDEF(type) 
  82 //----------------------------------------------------------------------------- 
  84 //----------------------------------------------------------------------------- 
  86 IMPLEMENT_DYNAMIC_CLASS(wxJPEGHandler
,wxImageHandler
) 
  90 //------------- JPEG Data Source Manager 
  92 #define JPEG_IO_BUFFER_SIZE   2048 
  95     struct jpeg_source_mgr pub
;   /* public fields */ 
  97     JOCTET
* buffer
;               /* start of buffer */ 
  98     wxInputStream 
*stream
; 
 101 typedef wx_source_mgr 
* wx_src_ptr
; 
 106 CPP_METHODDEF(void) wx_init_source ( j_decompress_ptr 
WXUNUSED(cinfo
) ) 
 110 CPP_METHODDEF(wxjpeg_boolean
) wx_fill_input_buffer ( j_decompress_ptr cinfo 
) 
 112     wx_src_ptr src 
= (wx_src_ptr
) cinfo
->src
; 
 114     src
->pub
.next_input_byte 
= src
->buffer
; 
 115     src
->pub
.bytes_in_buffer 
= src
->stream
->Read(src
->buffer
, JPEG_IO_BUFFER_SIZE
).LastRead(); 
 117     if (src
->pub
.bytes_in_buffer 
== 0) // check for end-of-stream 
 119         // Insert a fake EOI marker 
 120         src
->buffer
[0] = 0xFF; 
 121         src
->buffer
[1] = JPEG_EOI
; 
 122         src
->pub
.bytes_in_buffer 
= 2; 
 127 CPP_METHODDEF(void) wx_skip_input_data ( j_decompress_ptr cinfo
, long num_bytes 
) 
 131         wx_src_ptr src 
= (wx_src_ptr
) cinfo
->src
; 
 133         while (num_bytes 
> (long)src
->pub
.bytes_in_buffer
) 
 135             num_bytes 
-= (long) src
->pub
.bytes_in_buffer
; 
 136             src
->pub
.fill_input_buffer(cinfo
); 
 138         src
->pub
.next_input_byte 
+= (size_t) num_bytes
; 
 139         src
->pub
.bytes_in_buffer 
-= (size_t) num_bytes
; 
 143 CPP_METHODDEF(void) wx_term_source ( j_decompress_ptr cinfo 
) 
 145     wx_src_ptr src 
= (wx_src_ptr
) cinfo
->src
; 
 147     if (src
->pub
.bytes_in_buffer 
> 0) 
 148         src
->stream
->SeekI(-(long)src
->pub
.bytes_in_buffer
, wxFromCurrent
); 
 149     delete[] src
->buffer
; 
 153 // JPEG error manager: 
 155 struct wx_error_mgr 
{ 
 156   struct jpeg_error_mgr pub
;    /* "public" fields */ 
 158   jmp_buf setjmp_buffer
;    /* for return to caller */ 
 161 typedef struct wx_error_mgr 
* wx_error_ptr
; 
 164  * Here's the routine that will replace the standard error_exit method: 
 167 CPP_METHODDEF(void) wx_error_exit (j_common_ptr cinfo
) 
 169   /* cinfo->err really points to a wx_error_mgr struct, so coerce pointer */ 
 170   wx_error_ptr myerr 
= (wx_error_ptr
) cinfo
->err
; 
 172   /* Always display the message. */ 
 173   /* We could postpone this until after returning, if we chose. */ 
 174   (*cinfo
->err
->output_message
) (cinfo
); 
 176   /* Return control to the setjmp point */ 
 177   longjmp(myerr
->setjmp_buffer
, 1); 
 181  * This will replace the standard output_message method when the user 
 182  * wants us to be silent (verbose==false). We must have such method instead of 
 183  * simply using NULL for cinfo->err->output_message because it's called 
 184  * unconditionally from within libjpeg when there's "garbage input". 
 186 CPP_METHODDEF(void) wx_ignore_message (j_common_ptr 
WXUNUSED(cinfo
)) 
 190 void wx_jpeg_io_src( j_decompress_ptr cinfo
, wxInputStream
& infile 
) 
 194     if (cinfo
->src 
== NULL
) {    /* first time for this JPEG object? */ 
 195         cinfo
->src 
= (struct jpeg_source_mgr 
*) 
 196             (*cinfo
->mem
->alloc_small
) ((j_common_ptr
) cinfo
, JPOOL_PERMANENT
, 
 197             sizeof(wx_source_mgr
)); 
 199     src 
= (wx_src_ptr
) cinfo
->src
; 
 200     src
->pub
.bytes_in_buffer 
= 0; /* forces fill_input_buffer on first read */ 
 201     src
->buffer 
= new JOCTET
[JPEG_IO_BUFFER_SIZE
]; 
 202     src
->pub
.next_input_byte 
= NULL
; /* until buffer loaded */ 
 203     src
->stream 
= &infile
; 
 205     src
->pub
.init_source 
= wx_init_source
; 
 206     src
->pub
.fill_input_buffer 
= wx_fill_input_buffer
; 
 207     src
->pub
.skip_input_data 
= wx_skip_input_data
; 
 208     src
->pub
.resync_to_restart 
= jpeg_resync_to_restart
; /* use default method */ 
 209     src
->pub
.term_source 
= wx_term_source
; 
 214 static inline void wx_cmyk_to_rgb(unsigned char* rgb
, const unsigned char* cmyk
) 
 216     register int k 
= 255 - cmyk
[3]; 
 217     register int k2 
= cmyk
[3]; 
 220     c 
= k 
+ k2 
* (255 - cmyk
[0]) / 255; 
 221     rgb
[0] = (unsigned char)((c 
> 255) ? 0 : (255 - c
)); 
 223     c 
= k 
+ k2 
* (255 - cmyk
[1]) / 255; 
 224     rgb
[1] = (unsigned char)((c 
> 255) ? 0 : (255 - c
)); 
 226     c 
= k 
+ k2 
* (255 - cmyk
[2]) / 255; 
 227     rgb
[2] = (unsigned char)((c 
> 255) ? 0 : (255 - c
)); 
 230 // temporarily disable the warning C4611 (interaction between '_setjmp' and 
 231 // C++ object destruction is non-portable) - I don't see any dtors here 
 233     #pragma warning(disable:4611) 
 236 bool wxJPEGHandler::LoadFile( wxImage 
*image
, wxInputStream
& stream
, bool verbose
, int WXUNUSED(index
) ) 
 238     struct jpeg_decompress_struct cinfo
; 
 239     struct wx_error_mgr jerr
; 
 243     cinfo
.err 
= jpeg_std_error( &jerr
.pub 
); 
 244     jerr
.pub
.error_exit 
= wx_error_exit
; 
 247         cinfo
.err
->output_message 
= wx_ignore_message
; 
 249     /* Establish the setjmp return context for wx_error_exit to use. */ 
 250     if (setjmp(jerr
.setjmp_buffer
)) { 
 251       /* If we get here, the JPEG code has signaled an error. 
 252        * We need to clean up the JPEG object, close the input file, and return. 
 255         wxLogError(_("JPEG: Couldn't load - file is probably corrupted.")); 
 256       (cinfo
.src
->term_source
)(&cinfo
); 
 257       jpeg_destroy_decompress(&cinfo
); 
 258       if (image
->Ok()) image
->Destroy(); 
 262     jpeg_create_decompress( &cinfo 
); 
 263     wx_jpeg_io_src( &cinfo
, stream 
); 
 264     jpeg_read_header( &cinfo
, TRUE 
); 
 267     if ((cinfo
.out_color_space 
== JCS_CMYK
) || (cinfo
.out_color_space 
== JCS_YCCK
)) 
 269         cinfo
.out_color_space 
= JCS_CMYK
; 
 272     else // all the rest is treated as RGB 
 274         cinfo
.out_color_space 
= JCS_RGB
; 
 278     jpeg_start_decompress( &cinfo 
); 
 280     image
->Create( cinfo
.image_width
, cinfo
.image_height 
); 
 282         jpeg_finish_decompress( &cinfo 
); 
 283         jpeg_destroy_decompress( &cinfo 
); 
 286     image
->SetMask( false ); 
 287     ptr 
= image
->GetData(); 
 289     unsigned stride 
= cinfo
.output_width 
* bytesPerPixel
; 
 290     JSAMPARRAY tempbuf 
= (*cinfo
.mem
->alloc_sarray
) 
 291                             ((j_common_ptr
) &cinfo
, JPOOL_IMAGE
, stride
, 1 ); 
 293     while ( cinfo
.output_scanline 
< cinfo
.output_height 
) 
 295         jpeg_read_scanlines( &cinfo
, tempbuf
, 1 ); 
 296         if (cinfo
.out_color_space 
== JCS_RGB
) 
 298             memcpy( ptr
, tempbuf
[0], stride 
); 
 303             const unsigned char* inptr 
= (const unsigned char*) tempbuf
[0]; 
 304             for (size_t i 
= 0; i 
< cinfo
.output_width
; i
++) 
 306                 wx_cmyk_to_rgb(ptr
, inptr
); 
 313     jpeg_finish_decompress( &cinfo 
); 
 314     jpeg_destroy_decompress( &cinfo 
); 
 319     struct jpeg_destination_mgr pub
; 
 321     wxOutputStream 
*stream
; 
 323 } wx_destination_mgr
; 
 325 typedef wx_destination_mgr 
* wx_dest_ptr
; 
 327 #define OUTPUT_BUF_SIZE  4096    /* choose an efficiently fwrite'able size */ 
 332 CPP_METHODDEF(void) wx_init_destination (j_compress_ptr cinfo
) 
 334     wx_dest_ptr dest 
= (wx_dest_ptr
) cinfo
->dest
; 
 336     /* Allocate the output buffer --- it will be released when done with image */ 
 337     dest
->buffer 
= (JOCTET 
*) 
 338         (*cinfo
->mem
->alloc_small
) ((j_common_ptr
) cinfo
, JPOOL_IMAGE
, 
 339         OUTPUT_BUF_SIZE 
* sizeof(JOCTET
)); 
 340     dest
->pub
.next_output_byte 
= dest
->buffer
; 
 341     dest
->pub
.free_in_buffer 
= OUTPUT_BUF_SIZE
; 
 344 CPP_METHODDEF(wxjpeg_boolean
) wx_empty_output_buffer (j_compress_ptr cinfo
) 
 346     wx_dest_ptr dest 
= (wx_dest_ptr
) cinfo
->dest
; 
 348     dest
->stream
->Write(dest
->buffer
, OUTPUT_BUF_SIZE
); 
 349     dest
->pub
.next_output_byte 
= dest
->buffer
; 
 350     dest
->pub
.free_in_buffer 
= OUTPUT_BUF_SIZE
; 
 354 CPP_METHODDEF(void) wx_term_destination (j_compress_ptr cinfo
) 
 356     wx_dest_ptr dest 
= (wx_dest_ptr
) cinfo
->dest
; 
 357     size_t datacount 
= OUTPUT_BUF_SIZE 
- dest
->pub
.free_in_buffer
; 
 358     /* Write any data remaining in the buffer */ 
 360         dest
->stream
->Write(dest
->buffer
, datacount
); 
 363 GLOBAL(void) wx_jpeg_io_dest (j_compress_ptr cinfo
, wxOutputStream
& outfile
) 
 367     if (cinfo
->dest 
== NULL
) {    /* first time for this JPEG object? */ 
 368         cinfo
->dest 
= (struct jpeg_destination_mgr 
*) 
 369             (*cinfo
->mem
->alloc_small
) ((j_common_ptr
) cinfo
, JPOOL_PERMANENT
, 
 370             sizeof(wx_destination_mgr
)); 
 373     dest 
= (wx_dest_ptr
) cinfo
->dest
; 
 374     dest
->pub
.init_destination 
= wx_init_destination
; 
 375     dest
->pub
.empty_output_buffer 
= wx_empty_output_buffer
; 
 376     dest
->pub
.term_destination 
= wx_term_destination
; 
 377     dest
->stream 
= &outfile
; 
 382 bool wxJPEGHandler::SaveFile( wxImage 
*image
, wxOutputStream
& stream
, bool verbose 
) 
 384     struct jpeg_compress_struct cinfo
; 
 385     struct wx_error_mgr jerr
; 
 386     JSAMPROW row_pointer
[1];    /* pointer to JSAMPLE row[s] */ 
 387     JSAMPLE 
*image_buffer
; 
 388     int stride
;                /* physical row width in image buffer */ 
 390     cinfo
.err 
= jpeg_std_error(&jerr
.pub
); 
 391     jerr
.pub
.error_exit 
= wx_error_exit
; 
 394         cinfo
.err
->output_message 
= wx_ignore_message
; 
 396     /* Establish the setjmp return context for wx_error_exit to use. */ 
 397     if (setjmp(jerr
.setjmp_buffer
)) 
 399         /* If we get here, the JPEG code has signaled an error. 
 400          * We need to clean up the JPEG object, close the input file, and return. 
 403             wxLogError(_("JPEG: Couldn't save image.")); 
 404          jpeg_destroy_compress(&cinfo
); 
 408     jpeg_create_compress(&cinfo
); 
 409     wx_jpeg_io_dest(&cinfo
, stream
); 
 411     cinfo
.image_width 
= image
->GetWidth(); 
 412     cinfo
.image_height 
= image
->GetHeight(); 
 413     cinfo
.input_components 
= 3; 
 414     cinfo
.in_color_space 
= JCS_RGB
; 
 415     jpeg_set_defaults(&cinfo
); 
 417     // TODO: 3rd parameter is force_baseline, what value should this be? 
 418     // Code says: "If force_baseline is TRUE, the computed quantization table entries 
 419     // are limited to 1..255 for JPEG baseline compatibility." 
 420     // 'Quality' is a number between 0 (terrible) and 100 (very good). 
 421     // The default (in jcparam.c, jpeg_set_defaults) is 75, 
 422     // and force_baseline is TRUE. 
 423     if (image
->HasOption(wxIMAGE_OPTION_QUALITY
)) 
 424         jpeg_set_quality(&cinfo
, image
->GetOptionInt(wxIMAGE_OPTION_QUALITY
), TRUE
); 
 426     // set the resolution fields in the output file 
 428     wxImageResolution res 
= GetResolutionFromOptions(*image
, &resX
, &resY
); 
 429     if ( res 
!= wxIMAGE_RESOLUTION_NONE 
) 
 431         cinfo
.X_density 
= resX
; 
 432         cinfo
.Y_density 
= resY
; 
 434         // it so happens that wxIMAGE_RESOLUTION_INCHES/CM values are the same 
 435         // ones as used by libjpeg, so we can assign them directly 
 436         cinfo
.density_unit 
= res
; 
 439     jpeg_start_compress(&cinfo
, TRUE
); 
 441     stride 
= cinfo
.image_width 
* 3;    /* JSAMPLEs per row in image_buffer */ 
 442     image_buffer 
= image
->GetData(); 
 443     while (cinfo
.next_scanline 
< cinfo
.image_height
) { 
 444         row_pointer
[0] = &image_buffer
[cinfo
.next_scanline 
* stride
]; 
 445         jpeg_write_scanlines( &cinfo
, row_pointer
, 1 ); 
 447     jpeg_finish_compress(&cinfo
); 
 448     jpeg_destroy_compress(&cinfo
); 
 454     #pragma warning(default:4611) 
 457 bool wxJPEGHandler::DoCanRead( wxInputStream
& stream 
) 
 459     unsigned char hdr
[2]; 
 461     if ( !stream
.Read(hdr
, WXSIZEOF(hdr
)) ) 
 464     return hdr
[0] == 0xFF && hdr
[1] == 0xD8; 
 467 #endif   // wxUSE_STREAMS 
 469 #endif   // wxUSE_LIBJPEG