src/common/imagiff.cpp

   1 /////////////////////////////////////////////////////////////////////////////
   2 // Name:        imagiff.h
   3 // Purpose:     wxImage handler for Amiga IFF images
   4 // Author:      Steffen Gutmann
   5 // RCS-ID:      $Id$
   6 // Copyright:   (c) Steffen Gutmann, 2002
   7 // Licence:     wxWindows licence
   8 /////////////////////////////////////////////////////////////////////////////
   9
  10 //        parts of the source are based on xviff by Thomas Meyer
  11 //        Permission for use in wxWindows has been gratefully given.
  12
  13 #ifdef __GNUG__
  14 #pragma implementation "imagiff.h"
  15 #endif
  16
  17 // For compilers that support precompilation, includes "wx.h".
  18 #include "wx/wxprec.h"
  19
  20 #ifdef __BORLANDC__
  21 #  pragma hdrstop
  22 #endif
  23
  24 #ifndef WX_PRECOMP
  25 #  include "wx/defs.h"
  26 #endif
  27
  28 #if wxUSE_IMAGE && wxUSE_IFF
  29
  30 #include "wx/imagiff.h"
  31 #include "wx/wfstream.h"
  32 #include "wx/log.h"
  33 #include "wx/intl.h"
  34
  35 #include <stdlib.h>
  36 #include <string.h>
  37
  38
  39 // --------------------------------------------------------------------------
  40 // Constants
  41 // --------------------------------------------------------------------------
  42
  43 // Error codes:
  44 //  Note that the error code wxIFF_TRUNCATED means that the image itself
  45 //  is most probably OK, but the decoder didn't reach the end of the data
  46 //  stream; this means that if it was not reading directly from file,
  47 //  the stream will not be correctly positioned.
  48 //
  49
  50 enum
  51 {
  52     wxIFF_OK = 0,                   /* everything was OK */
  53     wxIFF_INVFORMAT,                /* error in iff header */
  54     wxIFF_MEMERR,                   /* error allocating memory */
  55     wxIFF_TRUNCATED                 /* file appears to be truncated */
  56 };
  57
  58 // --------------------------------------------------------------------------
  59 // wxIFFDecoder class
  60 // --------------------------------------------------------------------------
  61
  62 // internal class for storing IFF image data
  63 class IFFImage
  64 {
  65 public:
  66     unsigned int w;                 /* width */
  67     unsigned int h;                 /* height */
  68     int transparent;                /* transparent color (-1 = none) */
  69     int colors;                     /* number of colors */
  70     unsigned char *p;               /* bitmap */
  71     unsigned char *pal;             /* palette */
  72
  73     IFFImage() : w(0), h(0), colors(0), p(0), pal(0) {}
  74     ~IFFImage() { delete [] p; delete [] pal; }
  75 };
  76
  77 class WXDLLEXPORT wxIFFDecoder
  78 {
  79 private:
  80     IFFImage *m_image;          // image data
  81     wxInputStream *m_f;         // input stream
  82     unsigned char *databuf;
  83     unsigned char *picptr;
  84     unsigned char *decomp_mem;
  85
  86     void Destroy();
  87
  88 public:
  89     // get data of current frame
  90     unsigned char* GetData() const;
  91     unsigned char* GetPalette() const;
  92     int GetNumColors() const;
  93     unsigned int GetWidth() const;
  94     unsigned int GetHeight() const;
  95     int GetTransparentColour() const;
  96
  97     // constructor, destructor, etc.
  98     wxIFFDecoder(wxInputStream *s);
  99     ~wxIFFDecoder() { Destroy(); }
 100     bool CanRead();
 101     int ReadIFF();
 102     bool ConvertToImage(wxImage *image) const;
 103 };
 104
 105
 106 //---------------------------------------------------------------------------
 107 // wxIFFDecoder constructor and destructor
 108 //---------------------------------------------------------------------------
 109
 110 wxIFFDecoder::wxIFFDecoder(wxInputStream *s)
 111 {
 112     m_f = s;
 113     m_image = 0;
 114     databuf = 0;
 115     decomp_mem = 0;
 116 }
 117
 118 void wxIFFDecoder::Destroy()
 119 {
 120     delete m_image;
 121     m_image = 0;
 122     delete [] databuf;
 123     databuf = 0;
 124     delete [] decomp_mem;
 125     decomp_mem = 0;
 126 }
 127
 128 //---------------------------------------------------------------------------
 129 // Convert this image to a wxImage object
 130 //---------------------------------------------------------------------------
 131
 132 // This function was designed by Vaclav Slavik
 133
 134 bool wxIFFDecoder::ConvertToImage(wxImage *image) const
 135 {
 136     // just in case...
 137     image->Destroy();
 138
 139     // create the image
 140     image->Create(GetWidth(), GetHeight());
 141
 142     if (!image->Ok())
 143         return FALSE;
 144
 145     unsigned char *pal = GetPalette();
 146     unsigned char *src = GetData();
 147     unsigned char *dst = image->GetData();
 148     int colors = GetNumColors();
 149     int transparent = GetTransparentColour();
 150     long i;
 151
 152     // set transparent colour mask
 153     if (transparent != -1)
 154     {
 155         for (i = 0; i < colors; i++)
 156         {
 157             if ((pal[3 * i + 0] == 255) &&
 158                 (pal[3 * i + 1] == 0) &&
 159                 (pal[3 * i + 2] == 255))
 160             {
 161                 pal[3 * i + 2] = 254;
 162             }
 163         }
 164
 165         pal[3 * transparent + 0] = 255,
 166         pal[3 * transparent + 1] = 0,
 167         pal[3 * transparent + 2] = 255;
 168
 169         image->SetMaskColour(255, 0, 255);
 170     }
 171     else
 172         image->SetMask(FALSE);
 173
 174 #if wxUSE_PALETTE
 175     if (pal && colors > 0)
 176     {
 177         unsigned char* r = new unsigned char[colors];
 178         unsigned char* g = new unsigned char[colors];
 179         unsigned char* b = new unsigned char[colors];
 180
 181         for (i = 0; i < colors; i++)
 182         {
 183             r[i] = pal[3*i + 0];
 184             g[i] = pal[3*i + 1];
 185             b[i] = pal[3*i + 2];
 186         }
 187
 188         image->SetPalette(wxPalette(colors, r, g, b));
 189
 190         delete [] r;
 191         delete [] g;
 192         delete [] b;
 193     }
 194 #endif // wxUSE_PALETTE
 195
 196     // copy image data
 197     for (i = 0; i < (long)(GetWidth() * GetHeight()); i++, src += 3, dst += 3)
 198     {
 199     dst[0] = src[0];
 200     dst[1] = src[1];
 201     dst[2] = src[2];
 202     }
 203
 204     return TRUE;
 205 }
 206
 207
 208 //---------------------------------------------------------------------------
 209 // Data accessors
 210 //---------------------------------------------------------------------------
 211
 212 // Get data for current frame
 213
 214 unsigned char* wxIFFDecoder::GetData() const    { return (m_image->p); }
 215 unsigned char* wxIFFDecoder::GetPalette() const { return (m_image->pal); }
 216 int wxIFFDecoder::GetNumColors() const          { return m_image->colors; }
 217 unsigned int wxIFFDecoder::GetWidth() const     { return (m_image->w); }
 218 unsigned int wxIFFDecoder::GetHeight() const    { return (m_image->h); }
 219 int wxIFFDecoder::GetTransparentColour() const { return m_image->transparent; }
 220
 221 //---------------------------------------------------------------------------
 222 // IFF reading and decoding
 223 //---------------------------------------------------------------------------
 224
 225 //
 226 // CanRead:
 227 //  Returns TRUE if the file looks like a valid IFF, FALSE otherwise.
 228 //
 229 bool wxIFFDecoder::CanRead()
 230 {
 231     unsigned char buf[12] = "";
 232
 233     m_f->Read(buf, 12);
 234     m_f->SeekI(-12, wxFromCurrent);
 235
 236     return (memcmp(buf, "FORM", 4) == 0 && memcmp(buf+8, "ILBM", 4) == 0);
 237 }
 238
 239
 240 // ReadIFF:
 241 // Based on xv source code by Thomas Meyer
 242 // Permission for use in wxWindows has been gratefully given.
 243
 244 typedef unsigned char byte;
 245 #define IFFDEBUG 0
 246
 247 /*************************************************************************
 248   void decomprle(source, destination, source length, buffer size)
 249
 250   Decompress run-length encoded data from source to destination. Terminates
 251   when source is decoded completely or destination buffer is full.
 252
 253   The decruncher is as optimized as I could make it, without risking
 254   safety in case of corrupt BODY chunks.
 255 **************************************************************************/
 256
 257 static void decomprle(const byte *sptr, byte *dptr, long slen, long dlen)
 258 {
 259     byte codeByte, dataByte;
 260
 261     while ((slen > 0) && (dlen > 0)) {
 262     // read control byte
 263     codeByte = *sptr++;
 264
 265     if (codeByte < 0x80) {
 266         codeByte++;
 267         if ((slen > (long) codeByte) && (dlen >= (long) codeByte)) {
 268         slen -= codeByte + 1;
 269         dlen -= codeByte;
 270         while (codeByte > 0) {
 271             *dptr++ = *sptr++;
 272             codeByte--;
 273         }
 274         }
 275         else slen = 0;
 276     }
 277
 278     else if (codeByte > 0x80) {
 279         codeByte = 0x81 - (codeByte & 0x7f);
 280         if ((slen > (long) 0) && (dlen >= (long) codeByte)) {
 281         dataByte = *sptr++;
 282         slen -= 2;
 283         dlen -= codeByte;
 284         while (codeByte > 0) {
 285             *dptr++ = dataByte;
 286             codeByte--;
 287         }
 288         }
 289         else slen = 0;
 290     }
 291     }
 292 }
 293
 294 /******************************************/
 295 static unsigned int iff_getword(const byte *ptr)
 296 {
 297     unsigned int v;
 298
 299     v = *ptr++;
 300     v = (v << 8) + *ptr;
 301     return v;
 302 }
 303
 304 /******************************************/
 305 static unsigned long iff_getlong(const byte *ptr)
 306 {
 307     unsigned long l;
 308
 309     l = *ptr++;
 310     l = (l << 8) + *ptr++;
 311     l = (l << 8) + *ptr++;
 312     l = (l << 8) + *ptr;
 313     return l;
 314 }
 315
 316 // Define internal ILBM types
 317 #define ILBM_NORMAL     0
 318 #define ILBM_EHB        1
 319 #define ILBM_HAM        2
 320 #define ILBM_HAM8       3
 321 #define ILBM_24BIT      4
 322
 323 int wxIFFDecoder::ReadIFF()
 324 {
 325     Destroy();
 326
 327     m_image = new IFFImage();
 328     if (m_image == 0) {
 329     Destroy();
 330     return wxIFF_MEMERR;
 331     }
 332
 333     // compute file length
 334     off_t currentPos = m_f->TellI();
 335     m_f->SeekI(0, wxFromEnd);
 336     long filesize = m_f->TellI();
 337     m_f->SeekI(currentPos, wxFromStart);
 338
 339     // allocate memory for complete file
 340     if ((databuf = new byte[filesize]) == 0) {
 341     Destroy();
 342     return wxIFF_MEMERR;
 343     }
 344
 345     m_f->Read(databuf, filesize);
 346     const byte *dataend = databuf + filesize;
 347
 348     // initialize work pointer. used to trace the buffer for IFF chunks
 349     const byte *dataptr = databuf;
 350
 351     // check for minmal size
 352     if (dataptr + 12 > dataend) {
 353     Destroy();
 354     return wxIFF_INVFORMAT;
 355     }
 356
 357     // check if we really got an IFF file
 358     if (strncmp((char *)dataptr, "FORM", 4) != 0) {
 359     Destroy();
 360     return wxIFF_INVFORMAT;
 361     }
 362
 363     dataptr = dataptr + 8;                  // skip ID and length of FORM
 364
 365     // check if the IFF file is an ILBM (picture) file
 366     if (strncmp((char *) dataptr, "ILBM", 4) != 0) {
 367     Destroy();
 368     return wxIFF_INVFORMAT;
 369     }
 370
 371     wxLogTrace(_T("iff"), _T("IFF ILBM file recognized"));
 372
 373     dataptr = dataptr + 4;                                // skip ID
 374
 375     //
 376     // main decoding loop. searches IFF chunks and handles them.
 377     // terminates when BODY chunk was found or dataptr ran over end of file
 378     //
 379     bool BMHDok = false, CMAPok = false, CAMGok = false;
 380     int bmhd_width = 0, bmhd_height = 0, bmhd_bitplanes = 0, bmhd_transcol = -1;
 381     byte bmhd_masking = 0, bmhd_compression = 0;
 382     long camg_viewmode = 0;
 383     int colors = 0;
 384     while (dataptr + 8 <= dataend) {
 385     // get chunk length and make even
 386     size_t chunkLen = (iff_getlong(dataptr + 4) + 1) & 0xfffffffe;
 387 #ifdef __VMS
 388        // Silence compiler warning
 389        int chunkLen_;
 390        chunkLen_ = chunkLen;
 391        if (chunkLen_ < 0) {     // format error?
 392 #else
 393        if (chunkLen < 0) {     // format error?
 394 #endif
 395           break;
 396     }
 397     bool truncated = (dataptr + 8 + chunkLen > dataend);
 398
 399     if (strncmp((char *)dataptr, "BMHD", 4) == 0) { // BMHD chunk?
 400         if (chunkLen < 12 + 2 || truncated) {
 401         break;
 402         }
 403         bmhd_width = iff_getword(dataptr + 8);      // width of picture
 404         bmhd_height= iff_getword(dataptr + 8 + 2);  // height of picture
 405         bmhd_bitplanes = *(dataptr + 8 + 8);        // # of bitplanes
 406         bmhd_masking  = *(dataptr + 8 + 9);
 407         bmhd_compression = *(dataptr + 8 + 10);     // get compression
 408         bmhd_transcol    = iff_getword(dataptr + 8 + 12);
 409         BMHDok = true;                              // got BMHD
 410         dataptr += 8 + chunkLen;                    // to next chunk
 411     }
 412     else if (strncmp((char *)dataptr, "CMAP", 4) == 0) { // CMAP ?
 413         if (truncated) {
 414         break;
 415         }
 416         const byte *cmapptr = dataptr + 8;
 417         colors = chunkLen / 3;                  // calc no of colors
 418
 419         delete m_image->pal;
 420         m_image->pal = 0;
 421         m_image->colors = colors;
 422         if (colors > 0) {
 423         m_image->pal = new byte[3*colors];
 424         if (!m_image->pal) {
 425             Destroy();
 426             return wxIFF_MEMERR;
 427         }
 428
 429         // copy colors to color map
 430         for (int i=0; i < colors; i++) {
 431             m_image->pal[3*i + 0] = *cmapptr++;
 432             m_image->pal[3*i + 1] = *cmapptr++;
 433             m_image->pal[3*i + 2] = *cmapptr++;
 434         }
 435         }
 436
 437         wxLogTrace(_T("iff"), _T("Read %d colors from IFF file."),
 438             colors);
 439
 440         CMAPok = true;                              // got CMAP
 441         dataptr += 8 + chunkLen;                    // to next chunk
 442     } else if (strncmp((char *)dataptr, "CAMG", 4) == 0) { // CAMG ?
 443         if (chunkLen < 4 || truncated) {
 444         break;
 445         }
 446         camg_viewmode = iff_getlong(dataptr + 8);   // get viewmodes
 447         CAMGok = true;                              // got CAMG
 448         dataptr += 8 + chunkLen;                    // to next chunk
 449     }
 450     else if (strncmp((char *)dataptr, "BODY", 4) == 0) { // BODY ?
 451         if (!BMHDok) {                              // BMHD found?
 452         break;
 453         }
 454         const byte *bodyptr = dataptr + 8;          // -> BODY data
 455
 456         if (truncated) {
 457         chunkLen = dataend - dataptr;
 458         }
 459
 460         //
 461             // if BODY is compressed, allocate buffer for decrunched BODY
 462         // and decompress it (run length encoding)
 463         //
 464         if (bmhd_compression == 1) {
 465         // calc size of decrunch buffer - (size of the actual pic.
 466         // decompressed in interleaved Amiga bitplane format)
 467
 468         size_t decomp_bufsize = (((bmhd_width + 15) >> 4) << 1)
 469             * bmhd_height * bmhd_bitplanes;
 470
 471         if ((decomp_mem = new byte[decomp_bufsize]) == 0) {
 472             Destroy();
 473             return wxIFF_MEMERR;
 474         }
 475
 476         decomprle(bodyptr, decomp_mem, chunkLen, decomp_bufsize);
 477         bodyptr = decomp_mem;                 // -> uncompressed BODY
 478         chunkLen = decomp_bufsize;
 479         delete [] databuf;
 480         databuf = 0;
 481         }
 482
 483         // the following determines the type of the ILBM file.
 484         // it's either NORMAL, EHB, HAM, HAM8 or 24BIT
 485
 486         int fmt = ILBM_NORMAL;                 // assume normal ILBM
 487         if (bmhd_bitplanes == 24) {
 488         fmt = ILBM_24BIT;
 489         } else if (bmhd_bitplanes == 8) {
 490         if (CAMGok && (camg_viewmode & 0x800)) {
 491             fmt = ILBM_HAM8;
 492         }
 493         } else if ((bmhd_bitplanes > 5) && CAMGok) {
 494         if (camg_viewmode & 0x80) {
 495             fmt = ILBM_EHB;
 496         } else if (camg_viewmode & 0x800) {
 497             fmt = ILBM_HAM;
 498         }
 499         }
 500
 501         wxLogTrace(_T("iff"),
 502             _T("LoadIFF: %s %dx%d, planes=%d (%d cols), comp=%d"),
 503             (fmt==ILBM_NORMAL) ? "Normal ILBM" :
 504             (fmt==ILBM_HAM)    ? "HAM ILBM" :
 505             (fmt==ILBM_HAM8)   ? "HAM8 ILBM" :
 506             (fmt==ILBM_EHB)    ? "EHB ILBM" :
 507             (fmt==ILBM_24BIT)  ? "24BIT ILBM" : "unknown ILBM",
 508             bmhd_width, bmhd_height, bmhd_bitplanes,
 509             1<<bmhd_bitplanes, bmhd_compression);
 510
 511         if ((fmt==ILBM_NORMAL) || (fmt==ILBM_EHB) || (fmt==ILBM_HAM)) {
 512         wxLogTrace(_T("iff"),
 513             _T("Converting CMAP from normal ILBM CMAP"));
 514
 515         switch(fmt) {
 516             case ILBM_NORMAL: colors = 1 << bmhd_bitplanes; break;
 517             case ILBM_EHB:    colors = 32*2; break;
 518             case ILBM_HAM:    colors = 16; break;
 519         }
 520
 521         if (colors > m_image->colors) {
 522             byte *pal = new byte[colors*3];
 523             if (!pal) {
 524             Destroy();
 525             return wxIFF_MEMERR;
 526             }
 527             int i;
 528             for (i = 0; i < m_image->colors; i++) {
 529             pal[3*i + 0] = m_image->pal[3*i + 0];
 530             pal[3*i + 1] = m_image->pal[3*i + 1];
 531             pal[3*i + 2] = m_image->pal[3*i + 2];
 532             }
 533             for (; i < colors; i++) {
 534             pal[3*i + 0] = 0;
 535             pal[3*i + 1] = 0;
 536             pal[3*i + 2] = 0;
 537             }
 538             delete m_image->pal;
 539             m_image->pal = pal;
 540             m_image->colors = colors;
 541         }
 542
 543             for (int i=0; i < colors; i++) {
 544             m_image->pal[3*i + 0] = (m_image->pal[3*i + 0] >> 4) * 17;
 545             m_image->pal[3*i + 1] = (m_image->pal[3*i + 1] >> 4) * 17;
 546             m_image->pal[3*i + 2] = (m_image->pal[3*i + 2] >> 4) * 17;
 547         }
 548         }
 549
 550         m_image->p = new byte[bmhd_width * bmhd_height * 3];
 551             byte *picptr = m_image->p;
 552         if (!picptr) {
 553         Destroy();
 554         return wxIFF_MEMERR;
 555         }
 556
 557         byte *pal = m_image->pal;
 558         int lineskip = ((bmhd_width + 15) >> 4) << 1;
 559             int height = chunkLen / (lineskip * bmhd_bitplanes);
 560
 561         if (bmhd_height < height) {
 562             height = bmhd_height;
 563         }
 564
 565         if (fmt == ILBM_HAM || fmt == ILBM_HAM8 || fmt == ILBM_24BIT) {
 566         byte *pic = picptr;
 567         const byte *workptr = bodyptr;
 568
 569         for (int i=0; i < height; i++) {
 570             byte bitmsk = 0x80;
 571             const byte *workptr2 = workptr;
 572
 573             // at start of each line, init RGB values to background
 574             byte rval = pal[0];
 575             byte gval = pal[1];
 576             byte bval = pal[2];
 577
 578             for (int j=0; j < bmhd_width; j++) {
 579             long col = 0;
 580             long colbit = 1;
 581             const byte *workptr3 = workptr2;
 582             for (int k=0; k < bmhd_bitplanes; k++) {
 583                 if (*workptr3 & bitmsk) {
 584                 col += colbit;
 585                 }
 586                 workptr3 += lineskip;
 587                 colbit <<= 1;
 588             }
 589
 590             if (fmt==ILBM_HAM) {
 591                 int c = (col & 0x0f);
 592                 switch (col & 0x30) {
 593                 case 0x00: if (c >= 0 && c < colors) {
 594                            rval = pal[3*c + 0];
 595                            gval = pal[3*c + 1];
 596                            bval = pal[3*c + 2];
 597                        }
 598                        break;
 599
 600                 case 0x10: bval = c * 17;
 601                        break;
 602
 603                 case 0x20: rval = c * 17;
 604                        break;
 605
 606                 case 0x30: gval = c * 17;
 607                        break;
 608                 }
 609             } else if (fmt == ILBM_HAM8) {
 610                 int c = (col & 0x3f);
 611                 switch(col & 0xc0) {
 612                 case 0x00: if (c >= 0 && c < colors) {
 613                            rval = pal[3*c + 0];
 614                            gval = pal[3*c + 1];
 615                            bval = pal[3*c + 2];
 616                        }
 617                        break;
 618
 619                 case 0x40: bval = (bval & 3) | (c << 2);
 620                        break;
 621
 622                 case 0x80: rval = (rval & 3) | (c << 2);
 623                        break;
 624
 625                 case 0xc0: gval = (rval & 3) | (c << 2);
 626                 }
 627             } else {
 628                 rval = col & 0xff;
 629                 gval = (col >> 8) & 0xff;
 630                 bval = (col >> 16) & 0xff;
 631             }
 632
 633             *pic++ = rval;
 634             *pic++ = gval;
 635             *pic++ = bval;
 636
 637             bitmsk = bitmsk >> 1;
 638             if (bitmsk == 0) {
 639                 bitmsk = 0x80;
 640                 workptr2++;
 641             }
 642             }
 643             workptr += lineskip * bmhd_bitplanes;
 644         }
 645         }  else if ((fmt == ILBM_NORMAL) || (fmt == ILBM_EHB)) {
 646         if (fmt == ILBM_EHB) {
 647             wxLogTrace(_T("iff"), _T("Doubling CMAP for EHB mode"));
 648
 649             for (int i=0; i<32; i++) {
 650             pal[3*(i + 32) + 0] = pal[3*i + 0] >> 1;
 651             pal[3*(i + 32) + 1] = pal[3*i + 1] >> 1;
 652             pal[3*(i + 32) + 2] = pal[3*i + 2] >> 1;
 653             }
 654         }
 655
 656         byte *pic = picptr;         // ptr to buffer
 657         const byte *workptr = bodyptr;  // ptr to pic, planar format
 658
 659         if (bmhd_height < height) {
 660             height = bmhd_height;
 661         }
 662
 663         for (int i=0; i < height; i++) {
 664             byte bitmsk = 0x80;                 // left most bit (mask)
 665             const byte *workptr2 = workptr;     // work ptr to source
 666             for (int j=0; j < bmhd_width; j++) {
 667             long col = 0;
 668             long colbit = 1;
 669             const byte *workptr3 = workptr2;  // 1st byte in 1st pln
 670
 671             for (int k=0; k < bmhd_bitplanes; k++) {
 672                 if (*workptr3 & bitmsk) { // if bit set in this pln
 673                 col = col + colbit; // add bit to chunky byte
 674                 }
 675                 workptr3 += lineskip;   // go to next line
 676                 colbit <<= 1;           // shift color bit
 677             }
 678
 679             if (col >= 0 && col < colors) {
 680                 pic[0] = pal[3*col + 0];
 681                 pic[1] = pal[3*col + 1];
 682                 pic[2] = pal[3*col + 2];
 683             } else {
 684                 pic[0] = pic[1] = pic[2] = 0;
 685             }
 686             pic += 3;
 687             bitmsk = bitmsk >> 1;   // shift mask to next bit
 688             if (bitmsk == 0) {      // if mask is zero
 689                 bitmsk = 0x80;      // reset mask
 690                 workptr2++;         // mv ptr to next byte
 691             }
 692             }
 693
 694             workptr += lineskip * bmhd_bitplanes;  // to next line
 695         }
 696         } else {
 697         break;      // unknown format
 698         }
 699
 700         m_image->w = bmhd_width;
 701         m_image->h = height;
 702         m_image->transparent = bmhd_transcol;
 703
 704         wxLogTrace(_T("iff"), _T("Loaded IFF picture %s"),
 705             truncated? "truncated" : "completely");
 706
 707         return (truncated? wxIFF_TRUNCATED : wxIFF_OK);
 708     } else {
 709         wxLogTrace(_T("iff"), _T("Skipping unknown chunk '%c%c%c%c'"),
 710                 *dataptr, *(dataptr+1), *(dataptr+2), *(dataptr+3));
 711
 712         dataptr = dataptr + 8 + chunkLen;      // skip unknown chunk
 713     }
 714     }
 715
 716     Destroy();
 717     return wxIFF_INVFORMAT;
 718 }
 719
 720
 721
 722 //-----------------------------------------------------------------------------
 723 // wxIFFHandler
 724 //-----------------------------------------------------------------------------
 725
 726 IMPLEMENT_DYNAMIC_CLASS(wxIFFHandler, wxImageHandler)
 727
 728 #if wxUSE_STREAMS
 729
 730 bool wxIFFHandler::LoadFile(wxImage *image, wxInputStream& stream,
 731                             bool verbose, int WXUNUSED(index))
 732 {
 733     wxIFFDecoder *decod;
 734     int error;
 735     bool ok;
 736
 737     decod = new wxIFFDecoder(&stream);
 738     error = decod->ReadIFF();
 739
 740     if ((error != wxIFF_OK) && (error != wxIFF_TRUNCATED))
 741     {
 742         if (verbose)
 743         {
 744             switch (error)
 745             {
 746                 case wxIFF_INVFORMAT:
 747                     wxLogError(_("IFF: error in IFF image format."));
 748                     break;
 749                 case wxIFF_MEMERR:
 750                     wxLogError(_("IFF: not enough memory."));
 751                     break;
 752                 default:
 753                     wxLogError(_("IFF: unknown error!!!"));
 754                     break;
 755             }
 756         }
 757         delete decod;
 758         return FALSE;
 759     }
 760
 761     if ((error == wxIFF_TRUNCATED) && verbose)
 762     {
 763         wxLogError(_("IFF: data stream seems to be truncated."));
 764         /* go on; image data is OK */
 765     }
 766
 767     ok = decod->ConvertToImage(image);
 768     delete decod;
 769
 770     return ok;
 771 }
 772
 773 bool wxIFFHandler::SaveFile(wxImage * WXUNUSED(image),
 774                             wxOutputStream& WXUNUSED(stream), bool verbose)
 775 {
 776     if (verbose)
 777         wxLogDebug(wxT("IFF: the handler is read-only!!"));
 778
 779     return FALSE;
 780 }
 781
 782 bool wxIFFHandler::DoCanRead(wxInputStream& stream)
 783 {
 784     wxIFFDecoder *decod;
 785     bool ok;
 786
 787     decod = new wxIFFDecoder(&stream);
 788     ok = decod->CanRead();
 789     delete decod;
 790
 791     return ok;
 792 }
 793
 794 #endif // wxUSE_STREAMS
 795
 796 #endif // wxUSE_IFF