1/* 2 * Copyright (c) 2011 Michael Niedermayer 3 * 4 * This file is part of FFmpeg. 5 * 6 * FFmpeg is free software; you can redistribute it and/or 7 * modify it under the terms of the GNU Lesser General Public 8 * License as published by the Free Software Foundation; either 9 * version 2.1 of the License, or (at your option) any later version. 10 * 11 * FFmpeg is distributed in the hope that it will be useful, 12 * but WITHOUT ANY WARRANTY; without even the implied warranty of 13 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU 14 * Lesser General Public License for more details. 15 * 16 * You should have received a copy of the GNU Lesser General Public 17 * License along with FFmpeg; if not, write to the Free Software 18 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA 19 * 20 * The vsrc_color filter from Stefano Sabatini was used as template to create 21 * this 22 */ 23 24/** 25 * @file 26 * Mandelbrot fraktal renderer 27 */ 28 29#include "avfilter.h" 30#include "formats.h" 31#include "video.h" 32#include "internal.h" 33#include "libavutil/imgutils.h" 34#include "libavutil/opt.h" 35#include "libavutil/parseutils.h" 36#include <float.h> 37#include <math.h> 38 39#define SQR(a) ((a)*(a)) 40 41enum Outer{ 42 ITERATION_COUNT, 43 NORMALIZED_ITERATION_COUNT, 44 WHITE, 45 OUTZ, 46}; 47 48enum Inner{ 49 BLACK, 50 PERIOD, 51 CONVTIME, 52 MINCOL, 53}; 54 55typedef struct Point { 56 double p[2]; 57 uint32_t val; 58} Point; 59 60typedef struct { 61 const AVClass *class; 62 int w, h; 63 AVRational frame_rate; 64 uint64_t pts; 65 int maxiter; 66 double start_x; 67 double start_y; 68 double start_scale; 69 double end_scale; 70 double end_pts; 71 double bailout; 72 enum Outer outer; 73 enum Inner inner; 74 int cache_allocated; 75 int cache_used; 76 Point *point_cache; 77 Point *next_cache; 78 double (*zyklus)[2]; 79 uint32_t dither; 80 81 double morphxf; 82 double morphyf; 83 double morphamp; 84} MBContext; 85 86#define OFFSET(x) offsetof(MBContext, x) 87#define FLAGS AV_OPT_FLAG_VIDEO_PARAM|AV_OPT_FLAG_FILTERING_PARAM 88 89static const AVOption mandelbrot_options[] = { 90 {"size", "set frame size", OFFSET(w), AV_OPT_TYPE_IMAGE_SIZE, {.str="640x480"}, CHAR_MIN, CHAR_MAX, FLAGS }, 91 {"s", "set frame size", OFFSET(w), AV_OPT_TYPE_IMAGE_SIZE, {.str="640x480"}, CHAR_MIN, CHAR_MAX, FLAGS }, 92 {"rate", "set frame rate", OFFSET(frame_rate), AV_OPT_TYPE_VIDEO_RATE, {.str="25"}, CHAR_MIN, CHAR_MAX, FLAGS }, 93 {"r", "set frame rate", OFFSET(frame_rate), AV_OPT_TYPE_VIDEO_RATE, {.str="25"}, CHAR_MIN, CHAR_MAX, FLAGS }, 94 {"maxiter", "set max iterations number", OFFSET(maxiter), AV_OPT_TYPE_INT, {.i64=7189}, 1, INT_MAX, FLAGS }, 95 {"start_x", "set the initial x position", OFFSET(start_x), AV_OPT_TYPE_DOUBLE, {.dbl=-0.743643887037158704752191506114774}, -100, 100, FLAGS }, 96 {"start_y", "set the initial y position", OFFSET(start_y), AV_OPT_TYPE_DOUBLE, {.dbl=-0.131825904205311970493132056385139}, -100, 100, FLAGS }, 97 {"start_scale", "set the initial scale value", OFFSET(start_scale), AV_OPT_TYPE_DOUBLE, {.dbl=3.0}, 0, FLT_MAX, FLAGS }, 98 {"end_scale", "set the terminal scale value", OFFSET(end_scale), AV_OPT_TYPE_DOUBLE, {.dbl=0.3}, 0, FLT_MAX, FLAGS }, 99 {"end_pts", "set the terminal pts value", OFFSET(end_pts), AV_OPT_TYPE_DOUBLE, {.dbl=400}, 0, INT64_MAX, FLAGS }, 100 {"bailout", "set the bailout value", OFFSET(bailout), AV_OPT_TYPE_DOUBLE, {.dbl=10}, 0, FLT_MAX, FLAGS }, 101 {"morphxf", "set morph x frequency", OFFSET(morphxf), AV_OPT_TYPE_DOUBLE, {.dbl=0.01}, -FLT_MAX, FLT_MAX, FLAGS }, 102 {"morphyf", "set morph y frequency", OFFSET(morphyf), AV_OPT_TYPE_DOUBLE, {.dbl=0.0123}, -FLT_MAX, FLT_MAX, FLAGS }, 103 {"morphamp", "set morph amplitude", OFFSET(morphamp), AV_OPT_TYPE_DOUBLE, {.dbl=0}, -FLT_MAX, FLT_MAX, FLAGS }, 104 105 {"outer", "set outer coloring mode", OFFSET(outer), AV_OPT_TYPE_INT, {.i64=NORMALIZED_ITERATION_COUNT}, 0, INT_MAX, FLAGS, "outer" }, 106 {"iteration_count", "set iteration count mode", 0, AV_OPT_TYPE_CONST, {.i64=ITERATION_COUNT}, INT_MIN, INT_MAX, FLAGS, "outer" }, 107 {"normalized_iteration_count", "set normalized iteration count mode", 0, AV_OPT_TYPE_CONST, {.i64=NORMALIZED_ITERATION_COUNT}, INT_MIN, INT_MAX, FLAGS, "outer" }, 108 {"white", "set white mode", 0, AV_OPT_TYPE_CONST, {.i64=WHITE}, INT_MIN, INT_MAX, FLAGS, "outer" }, 109 {"outz", "set outz mode", 0, AV_OPT_TYPE_CONST, {.i64=OUTZ}, INT_MIN, INT_MAX, FLAGS, "outer" }, 110 111 {"inner", "set inner coloring mode", OFFSET(inner), AV_OPT_TYPE_INT, {.i64=MINCOL}, 0, INT_MAX, FLAGS, "inner" }, 112 {"black", "set black mode", 0, AV_OPT_TYPE_CONST, {.i64=BLACK}, INT_MIN, INT_MAX, FLAGS, "inner"}, 113 {"period", "set period mode", 0, AV_OPT_TYPE_CONST, {.i64=PERIOD}, INT_MIN, INT_MAX, FLAGS, "inner"}, 114 {"convergence", "show time until convergence", 0, AV_OPT_TYPE_CONST, {.i64=CONVTIME}, INT_MIN, INT_MAX, FLAGS, "inner"}, 115 {"mincol", "color based on point closest to the origin of the iterations", 0, AV_OPT_TYPE_CONST, {.i64=MINCOL}, INT_MIN, INT_MAX, FLAGS, "inner"}, 116 117 {NULL}, 118}; 119 120AVFILTER_DEFINE_CLASS(mandelbrot); 121 122static av_cold int init(AVFilterContext *ctx) 123{ 124 MBContext *mb = ctx->priv; 125 126 mb->bailout *= mb->bailout; 127 128 mb->start_scale /=mb->h; 129 mb->end_scale /=mb->h; 130 131 mb->cache_allocated = mb->w * mb->h * 3; 132 mb->cache_used = 0; 133 mb->point_cache= av_malloc_array(mb->cache_allocated, sizeof(*mb->point_cache)); 134 mb-> next_cache= av_malloc_array(mb->cache_allocated, sizeof(*mb-> next_cache)); 135 mb-> zyklus = av_malloc_array(mb->maxiter + 16, sizeof(*mb->zyklus)); 136 137 return 0; 138} 139 140static av_cold void uninit(AVFilterContext *ctx) 141{ 142 MBContext *mb = ctx->priv; 143 144 av_freep(&mb->point_cache); 145 av_freep(&mb-> next_cache); 146 av_freep(&mb->zyklus); 147} 148 149static int query_formats(AVFilterContext *ctx) 150{ 151 static const enum AVPixelFormat pix_fmts[] = { 152 AV_PIX_FMT_BGR32, 153 AV_PIX_FMT_NONE 154 }; 155 156 ff_set_common_formats(ctx, ff_make_format_list(pix_fmts)); 157 return 0; 158} 159 160static int config_props(AVFilterLink *inlink) 161{ 162 AVFilterContext *ctx = inlink->src; 163 MBContext *mb = ctx->priv; 164 165 if (av_image_check_size(mb->w, mb->h, 0, ctx) < 0) 166 return AVERROR(EINVAL); 167 168 inlink->w = mb->w; 169 inlink->h = mb->h; 170 inlink->time_base = av_inv_q(mb->frame_rate); 171 172 return 0; 173} 174 175static void fill_from_cache(AVFilterContext *ctx, uint32_t *color, int *in_cidx, int *out_cidx, double py, double scale){ 176 MBContext *mb = ctx->priv; 177 if(mb->morphamp) 178 return; 179 for(; *in_cidx < mb->cache_used; (*in_cidx)++){ 180 Point *p= &mb->point_cache[*in_cidx]; 181 int x; 182 if(p->p[1] > py) 183 break; 184 x= round((p->p[0] - mb->start_x) / scale + mb->w/2); 185 if(x<0 || x >= mb->w) 186 continue; 187 if(color) color[x] = p->val; 188 if(out_cidx && *out_cidx < mb->cache_allocated) 189 mb->next_cache[(*out_cidx)++]= *p; 190 } 191} 192 193static int interpol(MBContext *mb, uint32_t *color, int x, int y, int linesize) 194{ 195 uint32_t a,b,c,d, i; 196 uint32_t ipol=0xFF000000; 197 int dist; 198 199 if(!x || !y || x+1==mb->w || y+1==mb->h) 200 return 0; 201 202 dist= FFMAX(FFABS(x-(mb->w>>1))*mb->h, FFABS(y-(mb->h>>1))*mb->w); 203 204 if(dist<(mb->w*mb->h>>3)) 205 return 0; 206 207 a=color[(x+1) + (y+0)*linesize]; 208 b=color[(x-1) + (y+1)*linesize]; 209 c=color[(x+0) + (y+1)*linesize]; 210 d=color[(x+1) + (y+1)*linesize]; 211 212 if(a&&c){ 213 b= color[(x-1) + (y+0)*linesize]; 214 d= color[(x+0) + (y-1)*linesize]; 215 }else if(b&&d){ 216 a= color[(x+1) + (y-1)*linesize]; 217 c= color[(x-1) + (y-1)*linesize]; 218 }else if(c){ 219 d= color[(x+0) + (y-1)*linesize]; 220 a= color[(x-1) + (y+0)*linesize]; 221 b= color[(x+1) + (y-1)*linesize]; 222 }else if(d){ 223 c= color[(x-1) + (y-1)*linesize]; 224 a= color[(x-1) + (y+0)*linesize]; 225 b= color[(x+1) + (y-1)*linesize]; 226 }else 227 return 0; 228 229 for(i=0; i<3; i++){ 230 int s= 8*i; 231 uint8_t ac= a>>s; 232 uint8_t bc= b>>s; 233 uint8_t cc= c>>s; 234 uint8_t dc= d>>s; 235 int ipolab= (ac + bc); 236 int ipolcd= (cc + dc); 237 if(FFABS(ipolab - ipolcd) > 5) 238 return 0; 239 if(FFABS(ac-bc)+FFABS(cc-dc) > 20) 240 return 0; 241 ipol |= ((ipolab + ipolcd + 2)/4)<<s; 242 } 243 color[x + y*linesize]= ipol; 244 return 1; 245} 246 247static void draw_mandelbrot(AVFilterContext *ctx, uint32_t *color, int linesize, int64_t pts) 248{ 249 MBContext *mb = ctx->priv; 250 int x,y,i, in_cidx=0, next_cidx=0, tmp_cidx; 251 double scale= mb->start_scale*pow(mb->end_scale/mb->start_scale, pts/mb->end_pts); 252 int use_zyklus=0; 253 fill_from_cache(ctx, NULL, &in_cidx, NULL, mb->start_y+scale*(-mb->h/2-0.5), scale); 254 tmp_cidx= in_cidx; 255 memset(color, 0, sizeof(*color)*mb->w); 256 for(y=0; y<mb->h; y++){ 257 int y1= y+1; 258 const double ci=mb->start_y+scale*(y-mb->h/2); 259 fill_from_cache(ctx, NULL, &in_cidx, &next_cidx, ci, scale); 260 if(y1<mb->h){ 261 memset(color+linesize*y1, 0, sizeof(*color)*mb->w); 262 fill_from_cache(ctx, color+linesize*y1, &tmp_cidx, NULL, ci + 3*scale/2, scale); 263 } 264 265 for(x=0; x<mb->w; x++){ 266 float av_uninit(epsilon); 267 const double cr=mb->start_x+scale*(x-mb->w/2); 268 double zr=cr; 269 double zi=ci; 270 uint32_t c=0; 271 double dv= mb->dither / (double)(1LL<<32); 272 mb->dither= mb->dither*1664525+1013904223; 273 274 if(color[x + y*linesize] & 0xFF000000) 275 continue; 276 if(!mb->morphamp){ 277 if(interpol(mb, color, x, y, linesize)){ 278 if(next_cidx < mb->cache_allocated){ 279 mb->next_cache[next_cidx ].p[0]= cr; 280 mb->next_cache[next_cidx ].p[1]= ci; 281 mb->next_cache[next_cidx++].val = color[x + y*linesize]; 282 } 283 continue; 284 } 285 }else{ 286 zr += cos(pts * mb->morphxf) * mb->morphamp; 287 zi += sin(pts * mb->morphyf) * mb->morphamp; 288 } 289 290 use_zyklus= (x==0 || mb->inner!=BLACK ||color[x-1 + y*linesize] == 0xFF000000); 291 if(use_zyklus) 292 epsilon= scale*1*sqrt(SQR(x-mb->w/2) + SQR(y-mb->h/2))/mb->w; 293 294#define Z_Z2_C(outr,outi,inr,ini)\ 295 outr= inr*inr - ini*ini + cr;\ 296 outi= 2*inr*ini + ci; 297 298#define Z_Z2_C_ZYKLUS(outr,outi,inr,ini, Z)\ 299 Z_Z2_C(outr,outi,inr,ini)\ 300 if(use_zyklus){\ 301 if(Z && fabs(mb->zyklus[i>>1][0]-outr)+fabs(mb->zyklus[i>>1][1]-outi) <= epsilon)\ 302 break;\ 303 }\ 304 mb->zyklus[i][0]= outr;\ 305 mb->zyklus[i][1]= outi;\ 306 307 308 309 for(i=0; i<mb->maxiter-8; i++){ 310 double t; 311 Z_Z2_C_ZYKLUS(t, zi, zr, zi, 0) 312 i++; 313 Z_Z2_C_ZYKLUS(zr, zi, t, zi, 1) 314 i++; 315 Z_Z2_C_ZYKLUS(t, zi, zr, zi, 0) 316 i++; 317 Z_Z2_C_ZYKLUS(zr, zi, t, zi, 1) 318 i++; 319 Z_Z2_C_ZYKLUS(t, zi, zr, zi, 0) 320 i++; 321 Z_Z2_C_ZYKLUS(zr, zi, t, zi, 1) 322 i++; 323 Z_Z2_C_ZYKLUS(t, zi, zr, zi, 0) 324 i++; 325 Z_Z2_C_ZYKLUS(zr, zi, t, zi, 1) 326 if(zr*zr + zi*zi > mb->bailout){ 327 i-= FFMIN(7, i); 328 for(; i<mb->maxiter; i++){ 329 zr= mb->zyklus[i][0]; 330 zi= mb->zyklus[i][1]; 331 if(zr*zr + zi*zi > mb->bailout){ 332 switch(mb->outer){ 333 case ITERATION_COUNT: 334 zr = i; 335 c = lrintf((sin(zr)+1)*127) + lrintf((sin(zr/1.234)+1)*127)*256*256 + lrintf((sin(zr/100)+1)*127)*256; 336 break; 337 case NORMALIZED_ITERATION_COUNT: 338 zr = i + log2(log(mb->bailout) / log(zr*zr + zi*zi)); 339 c = lrintf((sin(zr)+1)*127) + lrintf((sin(zr/1.234)+1)*127)*256*256 + lrintf((sin(zr/100)+1)*127)*256; 340 break; 341 case WHITE: 342 c = 0xFFFFFF; 343 break; 344 case OUTZ: 345 zr /= mb->bailout; 346 zi /= mb->bailout; 347 c = (((int)(zr*128+128))&0xFF)*256 + (((int)(zi*128+128))&0xFF); 348 } 349 break; 350 } 351 } 352 break; 353 } 354 } 355 if(!c){ 356 if(mb->inner==PERIOD){ 357 int j; 358 for(j=i-1; j; j--) 359 if(SQR(mb->zyklus[j][0]-zr) + SQR(mb->zyklus[j][1]-zi) < epsilon*epsilon*10) 360 break; 361 if(j){ 362 c= i-j; 363 c= ((c<<5)&0xE0) + ((c<<10)&0xE000) + ((c<<15)&0xE00000); 364 } 365 }else if(mb->inner==CONVTIME){ 366 c= floor(i*255.0/mb->maxiter+dv)*0x010101; 367 } else if(mb->inner==MINCOL){ 368 int j; 369 double closest=9999; 370 int closest_index=0; 371 for(j=i-1; j>=0; j--) 372 if(SQR(mb->zyklus[j][0]) + SQR(mb->zyklus[j][1]) < closest){ 373 closest= SQR(mb->zyklus[j][0]) + SQR(mb->zyklus[j][1]); 374 closest_index= j; 375 } 376 closest = sqrt(closest); 377 c= lrintf((mb->zyklus[closest_index][0]/closest+1)*127+dv) + lrintf((mb->zyklus[closest_index][1]/closest+1)*127+dv)*256; 378 } 379 } 380 c |= 0xFF000000; 381 color[x + y*linesize]= c; 382 if(next_cidx < mb->cache_allocated){ 383 mb->next_cache[next_cidx ].p[0]= cr; 384 mb->next_cache[next_cidx ].p[1]= ci; 385 mb->next_cache[next_cidx++].val = c; 386 } 387 } 388 fill_from_cache(ctx, NULL, &in_cidx, &next_cidx, ci + scale/2, scale); 389 } 390 FFSWAP(void*, mb->next_cache, mb->point_cache); 391 mb->cache_used = next_cidx; 392 if(mb->cache_used == mb->cache_allocated) 393 av_log(ctx, AV_LOG_INFO, "Mandelbrot cache is too small!\n"); 394} 395 396static int request_frame(AVFilterLink *link) 397{ 398 MBContext *mb = link->src->priv; 399 AVFrame *picref = ff_get_video_buffer(link, mb->w, mb->h); 400 if (!picref) 401 return AVERROR(ENOMEM); 402 403 picref->sample_aspect_ratio = (AVRational) {1, 1}; 404 picref->pts = mb->pts++; 405 406 draw_mandelbrot(link->src, (uint32_t*)picref->data[0], picref->linesize[0]/4, picref->pts); 407 return ff_filter_frame(link, picref); 408} 409 410static const AVFilterPad mandelbrot_outputs[] = { 411 { 412 .name = "default", 413 .type = AVMEDIA_TYPE_VIDEO, 414 .request_frame = request_frame, 415 .config_props = config_props, 416 }, 417 { NULL } 418}; 419 420AVFilter ff_vsrc_mandelbrot = { 421 .name = "mandelbrot", 422 .description = NULL_IF_CONFIG_SMALL("Render a Mandelbrot fractal."), 423 .priv_size = sizeof(MBContext), 424 .priv_class = &mandelbrot_class, 425 .init = init, 426 .uninit = uninit, 427 .query_formats = query_formats, 428 .inputs = NULL, 429 .outputs = mandelbrot_outputs, 430}; 431