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
30 #include "libavutil/imgutils.h"
31 #include "libavutil/opt.h"
32 #include "libavutil/parseutils.h"
36 #define SQR(a) ((a)*(a))
40 NORMALIZED_ITERATION_COUNT,
48 typedef struct Point {
75 #define OFFSET(x) offsetof(MBContext, x)
77 static const AVOption mandelbrot_options[] = {
78 {"size", "set frame size", OFFSET(size), AV_OPT_TYPE_STRING, {.str="640x480"}, CHAR_MIN, CHAR_MAX },
79 {"s", "set frame size", OFFSET(size), AV_OPT_TYPE_STRING, {.str="640x480"}, CHAR_MIN, CHAR_MAX },
80 {"rate", "set frame rate", OFFSET(rate), AV_OPT_TYPE_STRING, {.str="25"}, CHAR_MIN, CHAR_MAX },
81 {"r", "set frame rate", OFFSET(rate), AV_OPT_TYPE_STRING, {.str="25"}, CHAR_MIN, CHAR_MAX },
82 {"maxiter", "set max iterations number", OFFSET(maxiter), AV_OPT_TYPE_INT, {.dbl=4096}, 1, INT_MAX },
83 {"start_x", "set the initial x position", OFFSET(start_x), AV_OPT_TYPE_DOUBLE, {.dbl=-0.743643887037158704752191506114774}, -100, 100 },
84 {"start_y", "set the initial y position", OFFSET(start_y), AV_OPT_TYPE_DOUBLE, {.dbl=-0.131825904205311970493132056385139}, -100, 100 },
85 {"start_scale", "set the initial scale value", OFFSET(start_scale), AV_OPT_TYPE_DOUBLE, {.dbl=3.0}, 0, FLT_MAX },
86 {"end_scale", "set the terminal scale value", OFFSET(end_scale), AV_OPT_TYPE_DOUBLE, {.dbl=0.3}, 0, FLT_MAX },
87 {"end_pts", "set the terminal pts value", OFFSET(end_pts), AV_OPT_TYPE_DOUBLE, {.dbl=800}, 0, INT64_MAX },
88 {"bailout", "set the bailout value", OFFSET(bailout), AV_OPT_TYPE_DOUBLE, {.dbl=10}, 0, FLT_MAX },
90 {"outer", "set outer coloring mode", OFFSET(outer), AV_OPT_TYPE_INT, {.dbl=NORMALIZED_ITERATION_COUNT}, 0, INT_MAX, 0, "outer"},
91 {"iteration_count", "set iteration count mode", 0, AV_OPT_TYPE_CONST, {.dbl=ITERATION_COUNT}, INT_MIN, INT_MAX, 0, "outer" },
92 {"normalized_iteration_count", "set normalized iteration count mode", 0, AV_OPT_TYPE_CONST, {.dbl=NORMALIZED_ITERATION_COUNT}, INT_MIN, INT_MAX, 0, "outer" },
94 {"inner", "set inner coloring mode", OFFSET(inner), AV_OPT_TYPE_INT, {.dbl=BLACK}, 0, INT_MAX, 0, "inner"},
95 {"black", "set black mode", 0, AV_OPT_TYPE_CONST, {.dbl=BLACK}, INT_MIN, INT_MAX, 0, "inner" },
96 {"period", "set period mode", 0, AV_OPT_TYPE_CONST, {.dbl=PERIOD}, INT_MIN, INT_MAX, 0, "inner" },
101 static const char *mandelbrot_get_name(void *ctx)
106 static const AVClass mandelbrot_class = {
112 static av_cold int init(AVFilterContext *ctx, const char *args, void *opaque)
114 MBContext *mb = ctx->priv;
118 mb->class = &mandelbrot_class;
119 av_opt_set_defaults(mb);
121 if ((err = (av_set_options_string(mb, args, "=", ":"))) < 0) {
122 av_log(ctx, AV_LOG_ERROR, "Error parsing options string: '%s'\n", args);
125 mb->bailout *= mb->bailout;
127 if (av_parse_video_size(&mb->w, &mb->h, mb->size) < 0) {
128 av_log(ctx, AV_LOG_ERROR, "Invalid frame size: %s\n", mb->size);
129 return AVERROR(EINVAL);
131 mb->start_scale /=mb->h;
132 mb->end_scale /=mb->h;
134 if (av_parse_video_rate(&rate_q, mb->rate) < 0 ||
135 rate_q.den <= 0 || rate_q.num <= 0) {
136 av_log(ctx, AV_LOG_ERROR, "Invalid frame rate: %s\n", mb->rate);
137 return AVERROR(EINVAL);
139 mb->time_base.num = rate_q.den;
140 mb->time_base.den = rate_q.num;
142 mb->cache_allocated = mb->w * mb->h * 3;
144 mb->point_cache= av_malloc(sizeof(*mb->point_cache)*mb->cache_allocated);
145 mb-> next_cache= av_malloc(sizeof(*mb-> next_cache)*mb->cache_allocated);
146 mb-> zyklus = av_malloc(sizeof(*mb->zyklus) * mb->maxiter);
151 static av_cold void uninit(AVFilterContext *ctx)
153 MBContext *mb = ctx->priv;
157 av_freep(&mb->point_cache);
158 av_freep(&mb-> next_cache);
159 av_freep(&mb->zyklus);
162 static int query_formats(AVFilterContext *ctx)
164 static const enum PixelFormat pix_fmts[] = {
169 avfilter_set_common_pixel_formats(ctx, avfilter_make_format_list(pix_fmts));
173 static int config_props(AVFilterLink *inlink)
175 AVFilterContext *ctx = inlink->src;
176 MBContext *mb = ctx->priv;
178 if (av_image_check_size(mb->w, mb->h, 0, ctx) < 0)
179 return AVERROR(EINVAL);
183 inlink->time_base = mb->time_base;
188 static void fill_from_cache(AVFilterContext *ctx, uint32_t *color, int *in_cidx, int *out_cidx, double py, double scale){
189 MBContext *mb = ctx->priv;
190 for(; *in_cidx < mb->cache_used; (*in_cidx)++){
191 Point *p= &mb->point_cache[*in_cidx];
195 x= round((p->p[0] - mb->start_x) / scale + mb->w/2);
196 if(x<0 || x >= mb->w)
198 if(color) color[x] = p->val;
199 if(out_cidx && *out_cidx < mb->cache_allocated)
200 mb->next_cache[(*out_cidx)++]= *p;
204 static void draw_mandelbrot(AVFilterContext *ctx, uint32_t *color, int linesize, int64_t pts)
206 MBContext *mb = ctx->priv;
207 int x,y,i, in_cidx=0, next_cidx=0, tmp_cidx;
208 double scale= mb->start_scale*pow(mb->end_scale/mb->start_scale, pts/mb->end_pts);
210 fill_from_cache(ctx, NULL, &in_cidx, NULL, mb->start_y+scale*(-mb->h/2-0.5), scale);
211 for(y=0; y<mb->h; y++){
212 const double ci=mb->start_y+scale*(y-mb->h/2);
213 memset(color+linesize*y, 0, sizeof(*color)*mb->w);
214 fill_from_cache(ctx, color+linesize*y, &in_cidx, &next_cidx, ci, scale);
216 fill_from_cache(ctx, color+linesize*y, &tmp_cidx, NULL, ci + scale/2, scale);
218 for(x=0; x<mb->w; x++){
219 const double cr=mb->start_x+scale*(x-mb->w/2);
224 if(color[x + y*linesize] & 0xFF000000)
227 use_zyklus= (x==0 || mb->inner!=BLACK ||color[x-1 + y*linesize] == 0xFF000000);
229 for(i=0; i<mb->maxiter; i++){
231 if(zr*zr + zi*zi > mb->bailout){
233 case ITERATION_COUNT: zr = i - (SQR(zr-cr)+SQR(zi-ci) > SQR(mb->bailout)); break;
234 case NORMALIZED_ITERATION_COUNT: zr= i + log2(log(mb->bailout) / log(zr*zr + zi*zi)); break;
236 c= lrintf((sin(zr)+1)*127) + lrintf((sin(zr/1.234)+1)*127)*256*256 + lrintf((sin(zr/100)+1)*127)*256;
239 t= zr*zr - zi*zi + cr;
243 mb->zyklus[i][1]= zi;
249 if(mb->zyklus[i>>1][0]==zr && mb->zyklus[i>>1][1]==zi)
251 mb->zyklus[i][0]= zr;
252 mb->zyklus[i][1]= zi;
255 if(!c && mb->inner==PERIOD){
258 if(SQR(mb->zyklus[j][0]-zr) + SQR(mb->zyklus[j][1]-zi) < 0.0000000000000001)
262 c= ((c<<5)&0xE0) + ((c<<16)&0xE000) + ((c<<27)&0xE00000);
266 color[x + y*linesize]= c;
267 if(next_cidx < mb->cache_allocated){
268 mb->next_cache[next_cidx ].p[0]= cr;
269 mb->next_cache[next_cidx ].p[1]= ci;
270 mb->next_cache[next_cidx++].val = c;
273 fill_from_cache(ctx, NULL, &in_cidx, &next_cidx, ci + scale/2, scale);
275 FFSWAP(void*, mb->next_cache, mb->point_cache);
276 mb->cache_used = next_cidx;
277 if(mb->cache_used == mb->cache_allocated)
278 av_log(0, AV_LOG_INFO, "Mandelbrot cache is too small!\n");
281 static int request_frame(AVFilterLink *link)
283 MBContext *mb = link->src->priv;
284 AVFilterBufferRef *picref = avfilter_get_video_buffer(link, AV_PERM_WRITE, mb->w, mb->h);
285 picref->video->sample_aspect_ratio = (AVRational) {1, 1};
286 picref->pts = mb->pts++;
289 avfilter_start_frame(link, avfilter_ref_buffer(picref, ~0));
290 draw_mandelbrot(link->src, picref->data[0], picref->linesize[0]/4, picref->pts);
291 avfilter_draw_slice(link, 0, mb->h, 1);
292 avfilter_end_frame(link);
293 avfilter_unref_buffer(picref);
298 AVFilter avfilter_vsrc_mandelbrot = {
299 .name = "mandelbrot",
300 .description = NULL_IF_CONFIG_SMALL("Mandelbrot renderer"),
302 .priv_size = sizeof(MBContext),
306 .query_formats = query_formats,
308 .inputs = (const AVFilterPad[]) {{ .name = NULL}},
310 .outputs = (const AVFilterPad[]) {{ .name = "default",
311 .type = AVMEDIA_TYPE_VIDEO,
312 .request_frame = request_frame,
313 .config_props = config_props },