synfig-core/trunk/src/modules/mod_gif/trgt_gif.cpp

   1 /*! ========================================================================
   2 ** Sinfg
   3 ** BMP Target Module
   4 ** $Id: trgt_gif.cpp,v 1.1.1.1 2005/01/04 01:23:10 darco Exp $
   5 **
   6 ** Copyright (c) 2002 Robert B. Quattlebaum Jr.
   7 **
   8 ** This software and associated documentation
   9 ** are CONFIDENTIAL and PROPRIETARY property of
  10 ** the above-mentioned copyright holder.
  11 **
  12 ** You may not copy, print, publish, or in any
  13 ** other way distribute this software without
  14 ** a prior written agreement with
  15 ** the copyright holder.
  16 **
  17 ** === N O T E S ===========================================================
  18 **
  19 ** ========================================================================= */
  20
  21 /* === H E A D E R S ======================================================= */
  22
  23 #define SINFG_TARGET
  24
  25 #ifdef USING_PCH
  26 #       include "pch.h"
  27 #else
  28 #ifdef HAVE_CONFIG_H
  29 #       include <config.h>
  30 #endif
  31
  32 #include <ETL/stringf>
  33 #include "trgt_gif.h"
  34 #include <stdio.h>
  35 #endif
  36
  37 /* === M A C R O S ========================================================= */
  38
  39 using namespace sinfg;
  40 using namespace std;
  41 using namespace etl;
  42
  43 #define MAX_FRAME_RATE  (20.0)
  44
  45 /* === G L O B A L S ======================================================= */
  46
  47 SINFG_TARGET_INIT(gif);
  48 SINFG_TARGET_SET_NAME(gif,"gif");
  49 SINFG_TARGET_SET_EXT(gif,"gif");
  50 SINFG_TARGET_SET_VERSION(gif,"0.1");
  51 SINFG_TARGET_SET_CVS_ID(gif,"$Id: trgt_gif.cpp,v 1.1.1.1 2005/01/04 01:23:10 darco Exp $");
  52
  53 /* === M E T H O D S ======================================================= */
  54
  55 gif::gif(const char *filename_):
  56         filename(filename_),
  57         file( (filename=="-")?stdout:fopen(filename_,"wb") ),
  58         imagecount(0),
  59
  60         lossy(true),
  61         multi_image(false),
  62         dithering(true),
  63         color_bits(8),
  64         iframe_density(30),
  65         loop_count(0x7fff),
  66         local_palette(true)
  67 {
  68 }
  69
  70 gif::~gif()
  71 {
  72         if(file)
  73                 fputc(';',file.get());  // Image terminator
  74 }
  75
  76 bool
  77 gif::set_rend_desc(RendDesc *given_desc)
  78 {
  79         if(given_desc->get_frame_rate()>MAX_FRAME_RATE)
  80                 given_desc->set_frame_rate(MAX_FRAME_RATE);
  81
  82         desc=*given_desc;
  83
  84         if(desc.get_frame_end()-desc.get_frame_start()>0)
  85         {
  86                 multi_image=true;
  87                 //set_remove_alpha();
  88                 imagecount=desc.get_frame_end()-desc.get_frame_start();
  89         }
  90         else
  91                 multi_image=false;
  92         return true;
  93 }
  94
  95 bool
  96 gif::init()
  97 {
  98         int w=desc.get_w(),h=desc.get_h();
  99
 100         if(!file)
 101         {
 102                 sinfg::error(strprintf(_("Unable to open \"%s\" for write access!"),filename.c_str()));
 103                 return false;
 104         }
 105
 106         rootsize=color_bits;    // Size of pixel bits
 107
 108         curr_frame.set_wh(w,h);
 109         prev_frame.set_wh(w,h);
 110         curr_surface.set_wh(w,h);
 111         curr_frame.clear();
 112         prev_frame.clear();
 113         curr_surface.clear();
 114
 115         if(get_quality()>5)
 116                 lossy=true;
 117         else
 118                 lossy=false;
 119
 120         // Output the header
 121         fprintf(file.get(),"GIF89a");
 122         fputc(w&0x000000ff,file.get());
 123         fputc((w&0x0000ff00)>>8,file.get());
 124         fputc(h&0x000000ff,file.get());
 125         fputc((h&0x0000ff00)>>8,file.get());
 126         if(!local_palette)
 127                 fputc(0xF0+(rootsize-1),file.get());    // flags
 128         else
 129                 fputc((0xF0+(rootsize-1))&~(1<<7),file.get());  // flags
 130
 131         fputc(0,file.get());            // backgound color
 132         fputc(0,file.get());            // Pixel Aspect Ratio
 133
 134         DEBUGPOINT();
 135
 136         if(!local_palette)
 137         {
 138         DEBUGPOINT();
 139                 curr_palette=Palette::grayscale(256/(1<<(8-rootsize))-1);
 140                 output_curr_palette();
 141         }
 142
 143         if(loop_count && multi_image)
 144         {
 145         DEBUGPOINT();
 146                 fputc(33,file.get()); // 33 (hex 0x21) GIF Extension code
 147                 fputc(255,file.get()); // 255 (hex 0xFF) Application Extension Label
 148                 fputc(11,file.get()); // 11 (hex (0x0B) Length of Application Block
 149                 fprintf(file.get(),"NETSCAPE2.0");
 150                 fputc(3,file.get()); // 3 (hex 0x03) Length of Data Sub-Block
 151                 fputc(1,file.get()); // 1 (hex 0x01)
 152                 fputc(loop_count&0x000000ff,file.get());
 153                 fputc((loop_count&0x0000ff00)>>8,file.get());
 154                 fputc(0,file.get()); // 0 (hex 0x00) a Data Sub-block Terminator.
 155         }
 156         DEBUGPOINT();
 157
 158         return true;
 159 }
 160
 161 void
 162 gif::output_curr_palette()
 163 {
 164         // Output the color table
 165         for(i=0;i<256/(1<<(8-rootsize));i++)
 166         {
 167 //              if(i && (i-1)<curr_palette.size())
 168                 {
 169                         Color color(curr_palette[i].color.clamped());
 170                         //fputc(i*(1<<(8-rootsize)),file.get());
 171                         //fputc(i*(1<<(8-rootsize)),file.get());
 172                         //fputc(i*(1<<(8-rootsize)),file.get());
 173                         fputc(gamma().r_F32_to_U8(color.get_r()),file.get());
 174                         fputc(gamma().g_F32_to_U8(color.get_g()),file.get());
 175                         fputc(gamma().b_F32_to_U8(color.get_b()),file.get());
 176                 }
 177 /*              else
 178                 {
 179                         fputc(255,file.get());
 180                         fputc(0,file.get());
 181                         fputc(255,file.get());
 182                 }
 183 */
 184         }
 185 }
 186
 187 bool
 188 gif::start_frame(sinfg::ProgressCallback *callback)
 189 {
 190 //      int
 191 //              w=desc.get_w(),
 192 //              h=desc.get_h();
 193
 194         if(!file)
 195         {
 196                 if(callback)callback->error(string("BUG:")+_("Description not set!"));
 197                 return false;
 198         }
 199
 200         if(callback)callback->task(filename+strprintf(" %d",imagecount));
 201
 202
 203
 204         return true;
 205 }
 206
 207 void
 208 gif::end_frame()
 209 {
 210         int w=desc.get_w(),h=desc.get_h(),i;
 211         unsigned int value;
 212         int
 213                 delaytime=round_to_int(100.0/desc.get_frame_rate());
 214
 215         bool build_off_previous(multi_image);
 216
 217         Palette prev_palette(curr_palette);
 218
 219         // Fill in the background color
 220         if(!get_remove_alpha())
 221         {
 222                 Surface::alpha_pen pen(curr_surface.begin(),1.0,Color::BLEND_BEHIND);
 223                 pen.set_value(get_canvas()->rend_desc().get_bg_color());
 224                 for(int y=0;y<curr_surface.get_h();y++,pen.inc_y())
 225                 {
 226                         int x;
 227                         for(x=0;x<curr_surface.get_w();x++,pen.inc_x())
 228                         {
 229                                 if(pen.get_value().get_a()>0.1)
 230                                         pen.put_value();
 231                                 else
 232                                         pen[0][0]=Color::alpha();
 233                         }
 234                         pen.dec_x(x);
 235                 }
 236         }
 237
 238         if(local_palette)
 239         {
 240                 curr_palette=Palette(curr_surface,256/(1<<(8-rootsize))-build_off_previous-1);
 241                 sinfg::info("curr_palette.size()=%d",curr_palette.size());
 242         }
 243
 244         int transparent_index(curr_palette.find_closest(Color(1,0,1,0))-curr_palette.begin());
 245         bool has_transparency(curr_palette[transparent_index].color.get_a()<=0.00001);
 246
 247         if(has_transparency)
 248                 build_off_previous=false;
 249
 250         if(build_off_previous)
 251         {
 252                 transparent_index=0;
 253                 has_transparency=true;
 254         }
 255
 256 #define DISPOSE_UNDEFINED                       (0)
 257 #define DISPOSE_NONE                            (1<<2)
 258 #define DISPOSE_RESTORE_BGCOLOR         (2<<2)
 259 #define DISPOSE_RESTORE_PREVIOUS        (3<<2)
 260         int gec_flags(0);
 261         if(build_off_previous)
 262                 gec_flags|=DISPOSE_NONE;
 263         else
 264                 gec_flags|=DISPOSE_RESTORE_PREVIOUS;
 265         if(has_transparency)
 266                 gec_flags|=1;
 267
 268         // output the Graphic Control Extension
 269         fputc(0x21,file.get()); // Extension introducer
 270         fputc(0xF9,file.get()); // Graphic Control Label
 271         fputc(4,file.get()); // Block Size
 272         fputc(gec_flags,file.get()); // Flags (Packed Fields)
 273         fputc(delaytime&0x000000ff,file.get()); // Delay Time (MSB)
 274         fputc((delaytime&0x0000ff00)>>8,file.get()); // Delay Time (LSB)
 275         fputc(transparent_index,file.get()); // Transparent Color Index
 276         fputc(0,file.get()); // Block Terminator
 277
 278         // output the image header
 279         fputc(',',file.get());
 280         fputc(0,file.get());    // image left
 281         fputc(0,file.get());    // image left
 282         fputc(0,file.get());    // image top
 283         fputc(0,file.get());    // image top
 284         fputc(w&0x000000ff,file.get());
 285         fputc((w&0x0000ff00)>>8,file.get());
 286         fputc(h&0x000000ff,file.get());
 287         fputc((h&0x0000ff00)>>8,file.get());
 288         if(local_palette)
 289                 fputc(0x80|(rootsize-1),file.get());    // flags
 290         else
 291                 fputc(0x00+ rootsize-1,file.get());     // flags
 292
 293
 294         if(local_palette)
 295         {
 296                 Palette out(curr_palette);
 297
 298                 if(build_off_previous)
 299                         curr_palette.insert(curr_palette.begin(),Color(1,0,1,0));
 300                 output_curr_palette();
 301                 curr_palette=out;
 302         }
 303
 304         bs=bitstream(file);
 305
 306         // Prepare ourselves for LZW compression
 307         codesize=rootsize+1;
 308         nextcode=(1<<rootsize)+2;
 309         table=lzwcode::NewTable((1<<rootsize));
 310         node=table;
 311
 312         // Output the rootsize
 313         fputc(rootsize,file.get());     // rootsize;
 314
 315         // Push a table reset into the bitstream
 316         bs.push_value(1<<rootsize,codesize);
 317
 318         for(int cur_scanline=0;cur_scanline<desc.get_h();cur_scanline++)
 319         {
 320                 //convert_color_format(curr_frame[cur_scanline], curr_surface[cur_scanline], desc.get_w(), PF_GRAY, gamma());
 321
 322                 // Now we compress it!
 323                 for(i=0;i<w;i++)
 324                 {
 325                         Color color(curr_surface[cur_scanline][i].clamped());
 326                         Palette::iterator iter(curr_palette.find_closest(color));
 327
 328                         if(dithering)
 329                         {
 330                                 Color error(color-iter->color);
 331                                 //error*=0.25;
 332                                 if(curr_surface.get_h()>cur_scanline+1)
 333                                 {
 334                                         curr_surface[cur_scanline+1][i-1]  += error * ((float)3/(float)16);
 335                                         curr_surface[cur_scanline+1][i]    += error * ((float)5/(float)16);
 336                                         if(curr_surface.get_w()>i+1)
 337                                                 curr_surface[cur_scanline+1][i+1]  += error * ((float)1/(float)16);
 338                                 }
 339                                 if(curr_surface.get_w()>i+1)
 340                                         curr_surface[cur_scanline][i+1]    += error * ((float)7/(float)16);
 341                         }
 342
 343                         curr_frame[cur_scanline][i]=iter-curr_palette.begin();
 344
 345                         value=curr_frame[cur_scanline][i];
 346                         if(build_off_previous)
 347                                 value++;
 348                         if(value>(unsigned)(1<<rootsize)-1)
 349                                 value=(1<<rootsize)-1;
 350
 351                         // If the pixel is the same as the one that
 352                         // is already there, then we should make it
 353                         // transparent
 354                         if(build_off_previous)
 355                         {
 356                                 if(lossy)
 357                                 {
 358
 359                                         // Lossy
 360                                         if(
 361                                                 abs( ( iter->color-prev_palette[prev_frame[cur_scanline][i]-1].color ).get_y() ) > (1.0/16.0) ||
 362 //                                              abs((int)value-(int)prev_frame[cur_scanline][i])>2||
 363 //                                              (value<=2 && value!=prev_frame[cur_scanline][i]) ||
 364                                                 (imagecount%iframe_density)==0 || imagecount==desc.get_frame_end()-1 ) // lossy version
 365                                                 prev_frame[cur_scanline][i]=value;
 366                                         else
 367                                         {
 368                                                 prev_frame[cur_scanline][i]=value;
 369                                                 value=0;
 370                                         }
 371                                 }
 372                                 else
 373                                 {
 374                                         // lossless version
 375                                         if(value!=prev_frame[cur_scanline][i])
 376                                                 prev_frame[cur_scanline][i]=value;
 377                                         else
 378                                                 value=0;
 379                                 }
 380                         }
 381                         else
 382                         prev_frame[cur_scanline][i]=value;
 383
 384                         next=node->FindCode(value);
 385                         if(next)
 386                                 node=next;
 387                         else
 388                         {
 389                                 node->AddNode(nextcode, value);
 390                                 bs.push_value(node->code, codesize);
 391                                 node = table->FindCode(value);
 392
 393                                 // Check to see if we need to increase the codesize
 394                                 if (nextcode == ( 1 << codesize))
 395                                         codesize += 1;
 396
 397                                 nextcode += 1;
 398
 399                                 // check to see if we have filled up the table
 400                                 if (nextcode == 4096)
 401                                 {
 402                                         // output the clear code: make sure to use the current
 403                                         // codesize
 404                                         bs.push_value((unsigned) 1 << rootsize, codesize);
 405
 406                                         delete table;
 407                                         table = lzwcode::NewTable((1<<rootsize));
 408                                         codesize = rootsize + 1;
 409                                         nextcode = (1 << rootsize) + 2;
 410
 411                                         // since we have a new table, need the correct prefix
 412                                         node = table->FindCode(value);
 413                                 }
 414                         }
 415                 }
 416         }
 417
 418
 419
 420
 421
 422         // Push the last code onto the bitstream
 423         bs.push_value(node->code,codesize);
 424
 425         // Push a end-of-stream code onto the bitstream
 426         bs.push_value((1<<rootsize)+1,codesize);
 427
 428         // Make sure everything is dumped out
 429         bs.dump();
 430
 431         delete table;
 432
 433         fputc(0,file.get());            // Block terminator
 434
 435         fflush(file.get());
 436         imagecount++;
 437 }
 438
 439 sinfg::Color*
 440 gif::start_scanline(int scanline)
 441 {
 442         cur_scanline=scanline;
 443         return curr_surface[scanline];
 444 }
 445
 446 bool
 447 gif::end_scanline()
 448 {
 449         if(!file)
 450                 return false;
 451
 452 //      int w=desc.get_w(),i;
 453 //      unsigned int value;
 454
 455
 456         return true;
 457 }