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

   1 /* === S Y N F I G ========================================================= */
   2 /*!     \file trgt_gif.cpp
   3 **      \brief BMP Target Module
   4 **
   5 **      $Id$
   6 **
   7 **      \legal
   8 **      Copyright (c) 2002-2005 Robert B. Quattlebaum Jr., Adrian Bentley
   9 **      Copyright (c) 2007 Chris Moore
  10 **
  11 **      This package is free software; you can redistribute it and/or
  12 **      modify it under the terms of the GNU General Public License as
  13 **      published by the Free Software Foundation; either version 2 of
  14 **      the License, or (at your option) any later version.
  15 **
  16 **      This package is distributed in the hope that it will be useful,
  17 **      but WITHOUT ANY WARRANTY; without even the implied warranty of
  18 **      MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
  19 **      General Public License for more details.
  20 **      \endlegal
  21 **
  22 ** === N O T E S ===========================================================
  23 **
  24 ** ========================================================================= */
  25
  26 /* === H E A D E R S ======================================================= */
  27
  28 #define SYNFIG_TARGET
  29
  30 #ifdef USING_PCH
  31 #       include "pch.h"
  32 #else
  33 #ifdef HAVE_CONFIG_H
  34 #       include <config.h>
  35 #endif
  36
  37 #include <ETL/stringf>
  38 #include "trgt_gif.h"
  39 #include <stdio.h>
  40 #endif
  41
  42 /* === M A C R O S ========================================================= */
  43
  44 using namespace synfig;
  45 using namespace std;
  46 using namespace etl;
  47
  48 #define MAX_FRAME_RATE  (20.0)
  49
  50 /* === G L O B A L S ======================================================= */
  51
  52 SYNFIG_TARGET_INIT(gif);
  53 SYNFIG_TARGET_SET_NAME(gif,"gif");
  54 SYNFIG_TARGET_SET_EXT(gif,"gif");
  55 SYNFIG_TARGET_SET_VERSION(gif,"0.1");
  56 SYNFIG_TARGET_SET_CVS_ID(gif,"$Id$");
  57
  58 /* === M E T H O D S ======================================================= */
  59
  60 gif::gif(const char *filename_):
  61         filename(filename_),
  62         file( (filename=="-")?stdout:fopen(filename_,POPEN_BINARY_WRITE_TYPE) ),
  63         imagecount(0),
  64
  65         lossy(true),
  66         multi_image(false),
  67         dithering(true),
  68         color_bits(8),
  69         iframe_density(30),
  70         loop_count(0x7fff),
  71         local_palette(true)
  72 {
  73 }
  74
  75 gif::~gif()
  76 {
  77         if(file)
  78                 fputc(';',file.get());  // Image terminator
  79 }
  80
  81 bool
  82 gif::set_rend_desc(RendDesc *given_desc)
  83 {
  84         if(given_desc->get_frame_rate()>MAX_FRAME_RATE)
  85                 given_desc->set_frame_rate(MAX_FRAME_RATE);
  86
  87         desc=*given_desc;
  88
  89         if(desc.get_frame_end()-desc.get_frame_start()>0)
  90         {
  91                 multi_image=true;
  92                 //set_remove_alpha();
  93                 imagecount=desc.get_frame_end()-desc.get_frame_start();
  94         }
  95         else
  96                 multi_image=false;
  97         return true;
  98 }
  99
 100 bool
 101 gif::init()
 102 {
 103         int w=desc.get_w(),h=desc.get_h();
 104
 105         if(!file)
 106         {
 107                 synfig::error(strprintf(_("Unable to open \"%s\" for write access!"),filename.c_str()));
 108                 return false;
 109         }
 110
 111         rootsize=color_bits;    // Size of pixel bits
 112
 113         curr_frame.set_wh(w,h);
 114         prev_frame.set_wh(w,h);
 115         curr_surface.set_wh(w,h);
 116         curr_frame.clear();
 117         prev_frame.clear();
 118         curr_surface.clear();
 119
 120         if(get_quality()>5)
 121                 lossy=true;
 122         else
 123                 lossy=false;
 124
 125         // Output the header
 126         fprintf(file.get(),"GIF89a");
 127         fputc(w&0x000000ff,file.get());
 128         fputc((w&0x0000ff00)>>8,file.get());
 129         fputc(h&0x000000ff,file.get());
 130         fputc((h&0x0000ff00)>>8,file.get());
 131         if(!local_palette)
 132                 fputc(0xF0+(rootsize-1),file.get());    // flags
 133         else
 134                 fputc((0xF0+(rootsize-1))&~(1<<7),file.get());  // flags
 135
 136         fputc(0,file.get());            // background color
 137         fputc(0,file.get());            // Pixel Aspect Ratio
 138
 139         if(!local_palette)
 140         {
 141                 curr_palette=Palette::grayscale(256/(1<<(8-rootsize))-1);
 142                 output_curr_palette();
 143         }
 144
 145         if(loop_count && multi_image)
 146         {
 147                 fputc(33,file.get()); // 33 (hex 0x21) GIF Extension code
 148                 fputc(255,file.get()); // 255 (hex 0xFF) Application Extension Label
 149                 fputc(11,file.get()); // 11 (hex (0x0B) Length of Application Block
 150                 fprintf(file.get(),"NETSCAPE2.0");
 151                 fputc(3,file.get()); // 3 (hex 0x03) Length of Data Sub-Block
 152                 fputc(1,file.get()); // 1 (hex 0x01)
 153                 fputc(loop_count&0x000000ff,file.get());
 154                 fputc((loop_count&0x0000ff00)>>8,file.get());
 155                 fputc(0,file.get()); // 0 (hex 0x00) a Data Sub-block Terminator.
 156         }
 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<(signed)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 bool
 187 gif::start_frame(synfig::ProgressCallback *callback)
 188 {
 189 //      int
 190 //              w=desc.get_w(),
 191 //              h=desc.get_h();
 192
 193         if(!file)
 194         {
 195                 if(callback)callback->error(string("BUG:")+_("Description not set!"));
 196                 return false;
 197         }
 198
 199         if(callback)callback->task(filename+strprintf(" %d",imagecount));
 200
 201
 202
 203         return true;
 204 }
 205
 206 void
 207 gif::end_frame()
 208 {
 209         int w=desc.get_w(),h=desc.get_h(),i;
 210         unsigned int value;
 211         int
 212                 delaytime=round_to_int(100.0/desc.get_frame_rate());
 213
 214         bool build_off_previous(multi_image);
 215
 216         Palette prev_palette(curr_palette);
 217
 218         // Fill in the background color
 219         if(!get_remove_alpha())
 220         {
 221                 Surface::alpha_pen pen(curr_surface.begin(),1.0,Color::BLEND_BEHIND);
 222                 pen.set_value(get_canvas()->rend_desc().get_bg_color());
 223                 for(int y=0;y<curr_surface.get_h();y++,pen.inc_y())
 224                 {
 225                         int x;
 226                         for(x=0;x<curr_surface.get_w();x++,pen.inc_x())
 227                         {
 228                                 if(pen.get_value().get_a()>0.1)
 229                                         pen.put_value();
 230                                 else
 231                                         pen[0][0]=Color::alpha();
 232                         }
 233                         pen.dec_x(x);
 234                 }
 235         }
 236
 237         if(local_palette)
 238         {
 239                 curr_palette=Palette(curr_surface,256/(1<<(8-rootsize))-build_off_previous-1);
 240                 synfig::info("curr_palette.size()=%d",curr_palette.size());
 241         }
 242
 243         int transparent_index(curr_palette.find_closest(Color(1,0,1,0))-curr_palette.begin());
 244         bool has_transparency(curr_palette[transparent_index].color.get_a()<=0.00001);
 245
 246         if(has_transparency)
 247                 build_off_previous=false;
 248
 249         if(build_off_previous)
 250         {
 251                 transparent_index=0;
 252                 has_transparency=true;
 253         }
 254
 255 #define DISPOSE_UNDEFINED                       (0)
 256 #define DISPOSE_NONE                            (1<<2)
 257 #define DISPOSE_RESTORE_BGCOLOR         (2<<2)
 258 #define DISPOSE_RESTORE_PREVIOUS        (3<<2)
 259         int gec_flags(0);
 260         if(build_off_previous)
 261                 gec_flags|=DISPOSE_NONE;
 262         else
 263                 gec_flags|=DISPOSE_RESTORE_PREVIOUS;
 264         if(has_transparency)
 265                 gec_flags|=1;
 266
 267         // output the Graphic Control Extension
 268         fputc(0x21,file.get()); // Extension introducer
 269         fputc(0xF9,file.get()); // Graphic Control Label
 270         fputc(4,file.get()); // Block Size
 271         fputc(gec_flags,file.get()); // Flags (Packed Fields)
 272         fputc(delaytime&0x000000ff,file.get()); // Delay Time (MSB)
 273         fputc((delaytime&0x0000ff00)>>8,file.get()); // Delay Time (LSB)
 274         fputc(transparent_index,file.get()); // Transparent Color Index
 275         fputc(0,file.get()); // Block Terminator
 276
 277         // output the image header
 278         fputc(',',file.get());
 279         fputc(0,file.get());    // image left
 280         fputc(0,file.get());    // image left
 281         fputc(0,file.get());    // image top
 282         fputc(0,file.get());    // image top
 283         fputc(w&0x000000ff,file.get());
 284         fputc((w&0x0000ff00)>>8,file.get());
 285         fputc(h&0x000000ff,file.get());
 286         fputc((h&0x0000ff00)>>8,file.get());
 287         if(local_palette)
 288                 fputc(0x80|(rootsize-1),file.get());    // flags
 289         else
 290                 fputc(0x00+ rootsize-1,file.get());     // flags
 291
 292
 293         if(local_palette)
 294         {
 295                 Palette out(curr_palette);
 296
 297                 if(build_off_previous)
 298                         curr_palette.insert(curr_palette.begin(),Color(1,0,1,0));
 299                 output_curr_palette();
 300                 curr_palette=out;
 301         }
 302
 303         bs=bitstream(file);
 304
 305         // Prepare ourselves for LZW compression
 306         codesize=rootsize+1;
 307         nextcode=(1<<rootsize)+2;
 308         table=lzwcode::NewTable((1<<rootsize));
 309         node=table;
 310
 311         // Output the rootsize
 312         fputc(rootsize,file.get());     // rootsize;
 313
 314         // Push a table reset into the bitstream
 315         bs.push_value(1<<rootsize,codesize);
 316
 317         for(int cur_scanline=0;cur_scanline<desc.get_h();cur_scanline++)
 318         {
 319                 //convert_color_format(curr_frame[cur_scanline], curr_surface[cur_scanline], desc.get_w(), PF_GRAY, gamma());
 320
 321                 // Now we compress it!
 322                 for(i=0;i<w;i++)
 323                 {
 324                         Color color(curr_surface[cur_scanline][i].clamped());
 325                         Palette::iterator iter(curr_palette.find_closest(color));
 326
 327                         if(dithering)
 328                         {
 329                                 Color error(color-iter->color);
 330                                 //error*=0.25;
 331                                 if(curr_surface.get_h()>cur_scanline+1)
 332                                 {
 333                                         curr_surface[cur_scanline+1][i-1]  += error * ((float)3/(float)16);
 334                                         curr_surface[cur_scanline+1][i]    += error * ((float)5/(float)16);
 335                                         if(curr_surface.get_w()>i+1)
 336                                                 curr_surface[cur_scanline+1][i+1]  += error * ((float)1/(float)16);
 337                                 }
 338                                 if(curr_surface.get_w()>i+1)
 339                                         curr_surface[cur_scanline][i+1]    += error * ((float)7/(float)16);
 340                         }
 341
 342                         curr_frame[cur_scanline][i]=iter-curr_palette.begin();
 343
 344                         value=curr_frame[cur_scanline][i];
 345                         if(build_off_previous)
 346                                 value++;
 347                         if(value>(unsigned)(1<<rootsize)-1)
 348                                 value=(1<<rootsize)-1;
 349
 350                         // If the pixel is the same as the one that
 351                         // is already there, then we should make it
 352                         // transparent
 353                         if(build_off_previous)
 354                         {
 355                                 if(lossy)
 356                                 {
 357
 358                                         // Lossy
 359                                         if(
 360                                                 abs( ( iter->color-prev_palette[prev_frame[cur_scanline][i]-1].color ).get_y() ) > (1.0/16.0) ||
 361 //                                              abs((int)value-(int)prev_frame[cur_scanline][i])>2||
 362 //                                              (value<=2 && value!=prev_frame[cur_scanline][i]) ||
 363                                                 (imagecount%iframe_density)==0 || imagecount==desc.get_frame_end()-1 ) // lossy version
 364                                                 prev_frame[cur_scanline][i]=value;
 365                                         else
 366                                         {
 367                                                 prev_frame[cur_scanline][i]=value;
 368                                                 value=0;
 369                                         }
 370                                 }
 371                                 else
 372                                 {
 373                                         // lossless version
 374                                         if(value!=prev_frame[cur_scanline][i])
 375                                                 prev_frame[cur_scanline][i]=value;
 376                                         else
 377                                                 value=0;
 378                                 }
 379                         }
 380                         else
 381                         prev_frame[cur_scanline][i]=value;
 382
 383                         next=node->FindCode(value);
 384                         if(next)
 385                                 node=next;
 386                         else
 387                         {
 388                                 node->AddNode(nextcode, value);
 389                                 bs.push_value(node->code, codesize);
 390                                 node = table->FindCode(value);
 391
 392                                 // Check to see if we need to increase the codesize
 393                                 if (nextcode == ( 1 << codesize))
 394                                         codesize += 1;
 395
 396                                 nextcode += 1;
 397
 398                                 // check to see if we have filled up the table
 399                                 if (nextcode == 4096)
 400                                 {
 401                                         // output the clear code: make sure to use the current
 402                                         // codesize
 403                                         bs.push_value((unsigned) 1 << rootsize, codesize);
 404
 405                                         delete table;
 406                                         table = lzwcode::NewTable((1<<rootsize));
 407                                         codesize = rootsize + 1;
 408                                         nextcode = (1 << rootsize) + 2;
 409
 410                                         // since we have a new table, need the correct prefix
 411                                         node = table->FindCode(value);
 412                                 }
 413                         }
 414                 }
 415         }
 416
 417
 418
 419
 420
 421         // Push the last code onto the bitstream
 422         bs.push_value(node->code,codesize);
 423
 424         // Push a end-of-stream code onto the bitstream
 425         bs.push_value((1<<rootsize)+1,codesize);
 426
 427         // Make sure everything is dumped out
 428         bs.dump();
 429
 430         delete table;
 431
 432         fputc(0,file.get());            // Block terminator
 433
 434         fflush(file.get());
 435         imagecount++;
 436 }
 437
 438 synfig::Color*
 439 gif::start_scanline(int scanline)
 440 {
 441         cur_scanline=scanline;
 442         return curr_surface[scanline];
 443 }
 444
 445 bool
 446 gif::end_scanline()
 447 {
 448         if(!file)
 449                 return false;
 450
 451 //      int w=desc.get_w(),i;
 452 //      unsigned int value;
 453
 454
 455         return true;
 456 }