1 /*! ========================================================================
4 ** $Id: trgt_gif.cpp,v 1.1.1.1 2005/01/04 01:23:10 darco Exp $
6 ** Copyright (c) 2002 Robert B. Quattlebaum Jr.
8 ** This software and associated documentation
9 ** are CONFIDENTIAL and PROPRIETARY property of
10 ** the above-mentioned copyright holder.
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.
17 ** === N O T E S ===========================================================
19 ** ========================================================================= */
21 /* === H E A D E R S ======================================================= */
32 #include <ETL/stringf>
37 /* === M A C R O S ========================================================= */
39 using namespace sinfg;
43 #define MAX_FRAME_RATE (20.0)
45 /* === G L O B A L S ======================================================= */
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 $");
53 /* === M E T H O D S ======================================================= */
55 gif::gif(const char *filename_):
57 file( (filename=="-")?stdout:fopen(filename_,"wb") ),
73 fputc(';',file.get()); // Image terminator
77 gif::set_rend_desc(RendDesc *given_desc)
79 if(given_desc->get_frame_rate()>MAX_FRAME_RATE)
80 given_desc->set_frame_rate(MAX_FRAME_RATE);
84 if(desc.get_frame_end()-desc.get_frame_start()>0)
88 imagecount=desc.get_frame_end()-desc.get_frame_start();
98 int w=desc.get_w(),h=desc.get_h();
102 sinfg::error(strprintf(_("Unable to open \"%s\" for write access!"),filename.c_str()));
106 rootsize=color_bits; // Size of pixel bits
108 curr_frame.set_wh(w,h);
109 prev_frame.set_wh(w,h);
110 curr_surface.set_wh(w,h);
113 curr_surface.clear();
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());
127 fputc(0xF0+(rootsize-1),file.get()); // flags
129 fputc((0xF0+(rootsize-1))&~(1<<7),file.get()); // flags
131 fputc(0,file.get()); // backgound color
132 fputc(0,file.get()); // Pixel Aspect Ratio
139 curr_palette=Palette::grayscale(256/(1<<(8-rootsize))-1);
140 output_curr_palette();
143 if(loop_count && multi_image)
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.
162 gif::output_curr_palette()
164 // Output the color table
165 for(i=0;i<256/(1<<(8-rootsize));i++)
167 // if(i && (i-1)<curr_palette.size())
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());
179 fputc(255,file.get());
181 fputc(255,file.get());
188 gif::start_frame(sinfg::ProgressCallback *callback)
196 if(callback)callback->error(string("BUG:")+_("Description not set!"));
200 if(callback)callback->task(filename+strprintf(" %d",imagecount));
210 int w=desc.get_w(),h=desc.get_h(),i;
213 delaytime=round_to_int(100.0/desc.get_frame_rate());
215 bool build_off_previous(multi_image);
217 Palette prev_palette(curr_palette);
219 // Fill in the background color
220 if(!get_remove_alpha())
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())
227 for(x=0;x<curr_surface.get_w();x++,pen.inc_x())
229 if(pen.get_value().get_a()>0.1)
232 pen[0][0]=Color::alpha();
240 curr_palette=Palette(curr_surface,256/(1<<(8-rootsize))-build_off_previous-1);
241 sinfg::info("curr_palette.size()=%d",curr_palette.size());
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);
248 build_off_previous=false;
250 if(build_off_previous)
253 has_transparency=true;
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)
261 if(build_off_previous)
262 gec_flags|=DISPOSE_NONE;
264 gec_flags|=DISPOSE_RESTORE_PREVIOUS;
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
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());
289 fputc(0x80|(rootsize-1),file.get()); // flags
291 fputc(0x00+ rootsize-1,file.get()); // flags
296 Palette out(curr_palette);
298 if(build_off_previous)
299 curr_palette.insert(curr_palette.begin(),Color(1,0,1,0));
300 output_curr_palette();
306 // Prepare ourselves for LZW compression
308 nextcode=(1<<rootsize)+2;
309 table=lzwcode::NewTable((1<<rootsize));
312 // Output the rootsize
313 fputc(rootsize,file.get()); // rootsize;
315 // Push a table reset into the bitstream
316 bs.push_value(1<<rootsize,codesize);
318 for(int cur_scanline=0;cur_scanline<desc.get_h();cur_scanline++)
320 //convert_color_format(curr_frame[cur_scanline], curr_surface[cur_scanline], desc.get_w(), PF_GRAY, gamma());
322 // Now we compress it!
325 Color color(curr_surface[cur_scanline][i].clamped());
326 Palette::iterator iter(curr_palette.find_closest(color));
330 Color error(color-iter->color);
332 if(curr_surface.get_h()>cur_scanline+1)
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);
339 if(curr_surface.get_w()>i+1)
340 curr_surface[cur_scanline][i+1] += error * ((float)7/(float)16);
343 curr_frame[cur_scanline][i]=iter-curr_palette.begin();
345 value=curr_frame[cur_scanline][i];
346 if(build_off_previous)
348 if(value>(unsigned)(1<<rootsize)-1)
349 value=(1<<rootsize)-1;
351 // If the pixel is the same as the one that
352 // is already there, then we should make it
354 if(build_off_previous)
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;
368 prev_frame[cur_scanline][i]=value;
375 if(value!=prev_frame[cur_scanline][i])
376 prev_frame[cur_scanline][i]=value;
382 prev_frame[cur_scanline][i]=value;
384 next=node->FindCode(value);
389 node->AddNode(nextcode, value);
390 bs.push_value(node->code, codesize);
391 node = table->FindCode(value);
393 // Check to see if we need to increase the codesize
394 if (nextcode == ( 1 << codesize))
399 // check to see if we have filled up the table
400 if (nextcode == 4096)
402 // output the clear code: make sure to use the current
404 bs.push_value((unsigned) 1 << rootsize, codesize);
407 table = lzwcode::NewTable((1<<rootsize));
408 codesize = rootsize + 1;
409 nextcode = (1 << rootsize) + 2;
411 // since we have a new table, need the correct prefix
412 node = table->FindCode(value);
422 // Push the last code onto the bitstream
423 bs.push_value(node->code,codesize);
425 // Push a end-of-stream code onto the bitstream
426 bs.push_value((1<<rootsize)+1,codesize);
428 // Make sure everything is dumped out
433 fputc(0,file.get()); // Block terminator
440 gif::start_scanline(int scanline)
442 cur_scanline=scanline;
443 return curr_surface[scanline];
452 // int w=desc.get_w(),i;
453 // unsigned int value;