2 * Copyright (c) 2011 Michael Niedermayer
4 * This file is part of FFmpeg.
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.
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.
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
20 * The vsrc_color filter from Stefano Sabatini was used as template to create
26 * Mandelbrot fraktal renderer
33 #include "libavutil/imgutils.h"
34 #include "libavutil/opt.h"
35 #include "libavutil/parseutils.h"
39 #define SQR(a) ((a)*(a))
43 NORMALIZED_ITERATION_COUNT,
55 typedef struct Point {
63 AVRational frame_rate;
86 #define OFFSET(x) offsetof(MBContext, x)
87 #define FLAGS AV_OPT_FLAG_VIDEO_PARAM|AV_OPT_FLAG_FILTERING_PARAM
89 static 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 },
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" },
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"},
120 AVFILTER_DEFINE_CLASS(mandelbrot);
122 static av_cold int init(AVFilterContext *ctx, const char *args)
124 MBContext *mb = ctx->priv;
126 mb->bailout *= mb->bailout;
128 mb->start_scale /=mb->h;
129 mb->end_scale /=mb->h;
131 mb->cache_allocated = mb->w * mb->h * 3;
133 mb->point_cache= av_malloc(sizeof(*mb->point_cache)*mb->cache_allocated);
134 mb-> next_cache= av_malloc(sizeof(*mb-> next_cache)*mb->cache_allocated);
135 mb-> zyklus = av_malloc(sizeof(*mb->zyklus) * (mb->maxiter+16));
140 static av_cold void uninit(AVFilterContext *ctx)
142 MBContext *mb = ctx->priv;
144 av_freep(&mb->point_cache);
145 av_freep(&mb-> next_cache);
146 av_freep(&mb->zyklus);
149 static int query_formats(AVFilterContext *ctx)
151 static const enum AVPixelFormat pix_fmts[] = {
156 ff_set_common_formats(ctx, ff_make_format_list(pix_fmts));
160 static int config_props(AVFilterLink *inlink)
162 AVFilterContext *ctx = inlink->src;
163 MBContext *mb = ctx->priv;
165 if (av_image_check_size(mb->w, mb->h, 0, ctx) < 0)
166 return AVERROR(EINVAL);
170 inlink->time_base = av_inv_q(mb->frame_rate);
175 static void fill_from_cache(AVFilterContext *ctx, uint32_t *color, int *in_cidx, int *out_cidx, double py, double scale){
176 MBContext *mb = ctx->priv;
179 for(; *in_cidx < mb->cache_used; (*in_cidx)++){
180 Point *p= &mb->point_cache[*in_cidx];
184 x= round((p->p[0] - mb->start_x) / scale + mb->w/2);
185 if(x<0 || x >= mb->w)
187 if(color) color[x] = p->val;
188 if(out_cidx && *out_cidx < mb->cache_allocated)
189 mb->next_cache[(*out_cidx)++]= *p;
193 static int interpol(MBContext *mb, uint32_t *color, int x, int y, int linesize)
196 uint32_t ipol=0xFF000000;
199 if(!x || !y || x+1==mb->w || y+1==mb->h)
202 dist= FFMAX(FFABS(x-(mb->w>>1))*mb->h, FFABS(y-(mb->h>>1))*mb->w);
204 if(dist<(mb->w*mb->h>>3))
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];
213 b= color[(x-1) + (y+0)*linesize];
214 d= color[(x+0) + (y-1)*linesize];
216 a= color[(x+1) + (y-1)*linesize];
217 c= color[(x-1) + (y-1)*linesize];
219 d= color[(x+0) + (y-1)*linesize];
220 a= color[(x-1) + (y+0)*linesize];
221 b= color[(x+1) + (y-1)*linesize];
223 c= color[(x-1) + (y-1)*linesize];
224 a= color[(x-1) + (y+0)*linesize];
225 b= color[(x+1) + (y-1)*linesize];
235 int ipolab= (ac + bc);
236 int ipolcd= (cc + dc);
237 if(FFABS(ipolab - ipolcd) > 5)
239 if(FFABS(ac-bc)+FFABS(cc-dc) > 20)
241 ipol |= ((ipolab + ipolcd + 2)/4)<<s;
243 color[x + y*linesize]= ipol;
247 static void draw_mandelbrot(AVFilterContext *ctx, uint32_t *color, int linesize, int64_t pts)
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);
253 fill_from_cache(ctx, NULL, &in_cidx, NULL, mb->start_y+scale*(-mb->h/2-0.5), scale);
255 memset(color, 0, sizeof(*color)*mb->w);
256 for(y=0; y<mb->h; y++){
258 const double ci=mb->start_y+scale*(y-mb->h/2);
259 fill_from_cache(ctx, NULL, &in_cidx, &next_cidx, ci, scale);
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);
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);
271 double dv= mb->dither / (double)(1LL<<32);
272 mb->dither= mb->dither*1664525+1013904223;
274 if(color[x + y*linesize] & 0xFF000000)
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];
286 zr += cos(pts * mb->morphxf) * mb->morphamp;
287 zi += sin(pts * mb->morphyf) * mb->morphamp;
290 use_zyklus= (x==0 || mb->inner!=BLACK ||color[x-1 + y*linesize] == 0xFF000000);
292 epsilon= scale*1*sqrt(SQR(x-mb->w/2) + SQR(y-mb->h/2))/mb->w;
294 #define Z_Z2_C(outr,outi,inr,ini)\
295 outr= inr*inr - ini*ini + cr;\
296 outi= 2*inr*ini + ci;
298 #define Z_Z2_C_ZYKLUS(outr,outi,inr,ini, Z)\
299 Z_Z2_C(outr,outi,inr,ini)\
301 if(Z && fabs(mb->zyklus[i>>1][0]-outr)+fabs(mb->zyklus[i>>1][1]-outi) <= epsilon)\
304 mb->zyklus[i][0]= outr;\
305 mb->zyklus[i][1]= outi;\
309 for(i=0; i<mb->maxiter-8; i++){
311 Z_Z2_C_ZYKLUS(t, zi, zr, zi, 0)
313 Z_Z2_C_ZYKLUS(zr, zi, t, zi, 1)
315 Z_Z2_C_ZYKLUS(t, zi, zr, zi, 0)
317 Z_Z2_C_ZYKLUS(zr, zi, t, zi, 1)
319 Z_Z2_C_ZYKLUS(t, zi, zr, zi, 0)
321 Z_Z2_C_ZYKLUS(zr, zi, t, zi, 1)
323 Z_Z2_C_ZYKLUS(t, zi, zr, zi, 0)
325 Z_Z2_C_ZYKLUS(zr, zi, t, zi, 1)
326 if(zr*zr + zi*zi > mb->bailout){
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){
333 case ITERATION_COUNT:
335 c = lrintf((sin(zr)+1)*127) + lrintf((sin(zr/1.234)+1)*127)*256*256 + lrintf((sin(zr/100)+1)*127)*256;
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;
347 c = (((int)(zr*128+128))&0xFF)*256 + (((int)(zi*128+128))&0xFF);
356 if(mb->inner==PERIOD){
359 if(SQR(mb->zyklus[j][0]-zr) + SQR(mb->zyklus[j][1]-zi) < epsilon*epsilon*10)
363 c= ((c<<5)&0xE0) + ((c<<10)&0xE000) + ((c<<15)&0xE00000);
365 }else if(mb->inner==CONVTIME){
366 c= floor(i*255.0/mb->maxiter+dv)*0x010101;
367 } else if(mb->inner==MINCOL){
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]);
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;
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;
388 fill_from_cache(ctx, NULL, &in_cidx, &next_cidx, ci + scale/2, scale);
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");
396 static int request_frame(AVFilterLink *link)
398 MBContext *mb = link->src->priv;
399 AVFrame *picref = ff_get_video_buffer(link, mb->w, mb->h);
401 return AVERROR(ENOMEM);
403 picref->sample_aspect_ratio = (AVRational) {1, 1};
404 picref->pts = mb->pts++;
406 draw_mandelbrot(link->src, (uint32_t*)picref->data[0], picref->linesize[0]/4, picref->pts);
407 return ff_filter_frame(link, picref);
410 static const AVFilterPad mandelbrot_outputs[] = {
413 .type = AVMEDIA_TYPE_VIDEO,
414 .request_frame = request_frame,
415 .config_props = config_props,
420 AVFilter avfilter_vsrc_mandelbrot = {
421 .name = "mandelbrot",
422 .description = NULL_IF_CONFIG_SMALL("Render a Mandelbrot fractal."),
424 .priv_size = sizeof(MBContext),
428 .query_formats = query_formats,
430 .outputs = mandelbrot_outputs,
431 .priv_class = &mandelbrot_class,