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00029 #include "avfilter.h"
00030 #include "formats.h"
00031 #include "video.h"
00032 #include "internal.h"
00033 #include "libavutil/imgutils.h"
00034 #include "libavutil/opt.h"
00035 #include "libavutil/parseutils.h"
00036 #include <float.h>
00037 #include <math.h>
00038
00039 #define SQR(a) ((a)*(a))
00040
00041 enum Outer{
00042 ITERATION_COUNT,
00043 NORMALIZED_ITERATION_COUNT,
00044 };
00045
00046 enum Inner{
00047 BLACK,
00048 PERIOD,
00049 CONVTIME,
00050 MINCOL,
00051 };
00052
00053 typedef struct Point {
00054 double p[2];
00055 uint32_t val;
00056 } Point;
00057
00058 typedef struct {
00059 const AVClass *class;
00060 int w, h;
00061 AVRational time_base;
00062 uint64_t pts;
00063 char *rate;
00064 int maxiter;
00065 double start_x;
00066 double start_y;
00067 double start_scale;
00068 double end_scale;
00069 double end_pts;
00070 double bailout;
00071 enum Outer outer;
00072 enum Inner inner;
00073 int cache_allocated;
00074 int cache_used;
00075 Point *point_cache;
00076 Point *next_cache;
00077 double (*zyklus)[2];
00078 uint32_t dither;
00079 } MBContext;
00080
00081 #define OFFSET(x) offsetof(MBContext, x)
00082 #define FLAGS AV_OPT_FLAG_VIDEO_PARAM|AV_OPT_FLAG_FILTERING_PARAM
00083
00084 static const AVOption mandelbrot_options[] = {
00085 {"size", "set frame size", OFFSET(w), AV_OPT_TYPE_IMAGE_SIZE, {.str="640x480"}, CHAR_MIN, CHAR_MAX, FLAGS },
00086 {"s", "set frame size", OFFSET(w), AV_OPT_TYPE_IMAGE_SIZE, {.str="640x480"}, CHAR_MIN, CHAR_MAX, FLAGS },
00087 {"rate", "set frame rate", OFFSET(rate), AV_OPT_TYPE_STRING, {.str="25"}, CHAR_MIN, CHAR_MAX, FLAGS },
00088 {"r", "set frame rate", OFFSET(rate), AV_OPT_TYPE_STRING, {.str="25"}, CHAR_MIN, CHAR_MAX, FLAGS },
00089 {"maxiter", "set max iterations number", OFFSET(maxiter), AV_OPT_TYPE_INT, {.i64=7189}, 1, INT_MAX, FLAGS },
00090 {"start_x", "set the initial x position", OFFSET(start_x), AV_OPT_TYPE_DOUBLE, {.dbl=-0.743643887037158704752191506114774}, -100, 100, FLAGS },
00091 {"start_y", "set the initial y position", OFFSET(start_y), AV_OPT_TYPE_DOUBLE, {.dbl=-0.131825904205311970493132056385139}, -100, 100, FLAGS },
00092 {"start_scale", "set the initial scale value", OFFSET(start_scale), AV_OPT_TYPE_DOUBLE, {.dbl=3.0}, 0, FLT_MAX, FLAGS },
00093 {"end_scale", "set the terminal scale value", OFFSET(end_scale), AV_OPT_TYPE_DOUBLE, {.dbl=0.3}, 0, FLT_MAX, FLAGS },
00094 {"end_pts", "set the terminal pts value", OFFSET(end_pts), AV_OPT_TYPE_DOUBLE, {.dbl=400}, 0, INT64_MAX, FLAGS },
00095 {"bailout", "set the bailout value", OFFSET(bailout), AV_OPT_TYPE_DOUBLE, {.dbl=10}, 0, FLT_MAX, FLAGS },
00096
00097 {"outer", "set outer coloring mode", OFFSET(outer), AV_OPT_TYPE_INT, {.i64=NORMALIZED_ITERATION_COUNT}, 0, INT_MAX, FLAGS, "outer" },
00098 {"iteration_count", "set iteration count mode", 0, AV_OPT_TYPE_CONST, {.i64=ITERATION_COUNT}, INT_MIN, INT_MAX, FLAGS, "outer" },
00099 {"normalized_iteration_count", "set normalized iteration count mode", 0, AV_OPT_TYPE_CONST, {.i64=NORMALIZED_ITERATION_COUNT}, INT_MIN, INT_MAX, FLAGS, "outer" },
00100
00101 {"inner", "set inner coloring mode", OFFSET(inner), AV_OPT_TYPE_INT, {.i64=MINCOL}, 0, INT_MAX, FLAGS, "inner" },
00102 {"black", "set black mode", 0, AV_OPT_TYPE_CONST, {.i64=BLACK}, INT_MIN, INT_MAX, FLAGS, "inner"},
00103 {"period", "set period mode", 0, AV_OPT_TYPE_CONST, {.i64=PERIOD}, INT_MIN, INT_MAX, FLAGS, "inner"},
00104 {"convergence", "show time until convergence", 0, AV_OPT_TYPE_CONST, {.i64=CONVTIME}, INT_MIN, INT_MAX, FLAGS, "inner"},
00105 {"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"},
00106
00107 {NULL},
00108 };
00109
00110 AVFILTER_DEFINE_CLASS(mandelbrot);
00111
00112 static av_cold int init(AVFilterContext *ctx, const char *args)
00113 {
00114 MBContext *mb = ctx->priv;
00115 AVRational rate_q;
00116 int err;
00117
00118 mb->class = &mandelbrot_class;
00119 av_opt_set_defaults(mb);
00120
00121 if ((err = (av_set_options_string(mb, args, "=", ":"))) < 0)
00122 return err;
00123 mb->bailout *= mb->bailout;
00124
00125 mb->start_scale /=mb->h;
00126 mb->end_scale /=mb->h;
00127
00128 if (av_parse_video_rate(&rate_q, mb->rate) < 0) {
00129 av_log(ctx, AV_LOG_ERROR, "Invalid frame rate: %s\n", mb->rate);
00130 return AVERROR(EINVAL);
00131 }
00132 mb->time_base.num = rate_q.den;
00133 mb->time_base.den = rate_q.num;
00134
00135 mb->cache_allocated = mb->w * mb->h * 3;
00136 mb->cache_used = 0;
00137 mb->point_cache= av_malloc(sizeof(*mb->point_cache)*mb->cache_allocated);
00138 mb-> next_cache= av_malloc(sizeof(*mb-> next_cache)*mb->cache_allocated);
00139 mb-> zyklus = av_malloc(sizeof(*mb->zyklus) * (mb->maxiter+16));
00140
00141 return 0;
00142 }
00143
00144 static av_cold void uninit(AVFilterContext *ctx)
00145 {
00146 MBContext *mb = ctx->priv;
00147
00148 av_freep(&mb->rate);
00149 av_freep(&mb->point_cache);
00150 av_freep(&mb-> next_cache);
00151 av_freep(&mb->zyklus);
00152 }
00153
00154 static int query_formats(AVFilterContext *ctx)
00155 {
00156 static const enum PixelFormat pix_fmts[] = {
00157 PIX_FMT_BGR32,
00158 PIX_FMT_NONE
00159 };
00160
00161 ff_set_common_formats(ctx, ff_make_format_list(pix_fmts));
00162 return 0;
00163 }
00164
00165 static int config_props(AVFilterLink *inlink)
00166 {
00167 AVFilterContext *ctx = inlink->src;
00168 MBContext *mb = ctx->priv;
00169
00170 if (av_image_check_size(mb->w, mb->h, 0, ctx) < 0)
00171 return AVERROR(EINVAL);
00172
00173 inlink->w = mb->w;
00174 inlink->h = mb->h;
00175 inlink->time_base = mb->time_base;
00176
00177 return 0;
00178 }
00179
00180 static void fill_from_cache(AVFilterContext *ctx, uint32_t *color, int *in_cidx, int *out_cidx, double py, double scale){
00181 MBContext *mb = ctx->priv;
00182 for(; *in_cidx < mb->cache_used; (*in_cidx)++){
00183 Point *p= &mb->point_cache[*in_cidx];
00184 int x;
00185 if(p->p[1] > py)
00186 break;
00187 x= round((p->p[0] - mb->start_x) / scale + mb->w/2);
00188 if(x<0 || x >= mb->w)
00189 continue;
00190 if(color) color[x] = p->val;
00191 if(out_cidx && *out_cidx < mb->cache_allocated)
00192 mb->next_cache[(*out_cidx)++]= *p;
00193 }
00194 }
00195
00196 static int interpol(MBContext *mb, uint32_t *color, int x, int y, int linesize)
00197 {
00198 uint32_t a,b,c,d, i;
00199 uint32_t ipol=0xFF000000;
00200 int dist;
00201
00202 if(!x || !y || x+1==mb->w || y+1==mb->h)
00203 return 0;
00204
00205 dist= FFMAX(FFABS(x-(mb->w>>1))*mb->h, FFABS(y-(mb->h>>1))*mb->w);
00206
00207 if(dist<(mb->w*mb->h>>3))
00208 return 0;
00209
00210 a=color[(x+1) + (y+0)*linesize];
00211 b=color[(x-1) + (y+1)*linesize];
00212 c=color[(x+0) + (y+1)*linesize];
00213 d=color[(x+1) + (y+1)*linesize];
00214
00215 if(a&&c){
00216 b= color[(x-1) + (y+0)*linesize];
00217 d= color[(x+0) + (y-1)*linesize];
00218 }else if(b&&d){
00219 a= color[(x+1) + (y-1)*linesize];
00220 c= color[(x-1) + (y-1)*linesize];
00221 }else if(c){
00222 d= color[(x+0) + (y-1)*linesize];
00223 a= color[(x-1) + (y+0)*linesize];
00224 b= color[(x+1) + (y-1)*linesize];
00225 }else if(d){
00226 c= color[(x-1) + (y-1)*linesize];
00227 a= color[(x-1) + (y+0)*linesize];
00228 b= color[(x+1) + (y-1)*linesize];
00229 }else
00230 return 0;
00231
00232 for(i=0; i<3; i++){
00233 int s= 8*i;
00234 uint8_t ac= a>>s;
00235 uint8_t bc= b>>s;
00236 uint8_t cc= c>>s;
00237 uint8_t dc= d>>s;
00238 int ipolab= (ac + bc);
00239 int ipolcd= (cc + dc);
00240 if(FFABS(ipolab - ipolcd) > 5)
00241 return 0;
00242 if(FFABS(ac-bc)+FFABS(cc-dc) > 20)
00243 return 0;
00244 ipol |= ((ipolab + ipolcd + 2)/4)<<s;
00245 }
00246 color[x + y*linesize]= ipol;
00247 return 1;
00248 }
00249
00250 static void draw_mandelbrot(AVFilterContext *ctx, uint32_t *color, int linesize, int64_t pts)
00251 {
00252 MBContext *mb = ctx->priv;
00253 int x,y,i, in_cidx=0, next_cidx=0, tmp_cidx;
00254 double scale= mb->start_scale*pow(mb->end_scale/mb->start_scale, pts/mb->end_pts);
00255 int use_zyklus=0;
00256 fill_from_cache(ctx, NULL, &in_cidx, NULL, mb->start_y+scale*(-mb->h/2-0.5), scale);
00257 tmp_cidx= in_cidx;
00258 memset(color, 0, sizeof(*color)*mb->w);
00259 for(y=0; y<mb->h; y++){
00260 int y1= y+1;
00261 const double ci=mb->start_y+scale*(y-mb->h/2);
00262 fill_from_cache(ctx, NULL, &in_cidx, &next_cidx, ci, scale);
00263 if(y1<mb->h){
00264 memset(color+linesize*y1, 0, sizeof(*color)*mb->w);
00265 fill_from_cache(ctx, color+linesize*y1, &tmp_cidx, NULL, ci + 3*scale/2, scale);
00266 }
00267
00268 for(x=0; x<mb->w; x++){
00269 float av_uninit(epsilon);
00270 const double cr=mb->start_x+scale*(x-mb->w/2);
00271 double zr=cr;
00272 double zi=ci;
00273 uint32_t c=0;
00274 double dv= mb->dither / (double)(1LL<<32);
00275 mb->dither= mb->dither*1664525+1013904223;
00276
00277 if(color[x + y*linesize] & 0xFF000000)
00278 continue;
00279 if(interpol(mb, color, x, y, linesize)){
00280 if(next_cidx < mb->cache_allocated){
00281 mb->next_cache[next_cidx ].p[0]= cr;
00282 mb->next_cache[next_cidx ].p[1]= ci;
00283 mb->next_cache[next_cidx++].val = color[x + y*linesize];
00284 }
00285 continue;
00286 }
00287
00288 use_zyklus= (x==0 || mb->inner!=BLACK ||color[x-1 + y*linesize] == 0xFF000000);
00289 if(use_zyklus)
00290 epsilon= scale*1*sqrt(SQR(x-mb->w/2) + SQR(y-mb->h/2))/mb->w;
00291
00292 #define Z_Z2_C(outr,outi,inr,ini)\
00293 outr= inr*inr - ini*ini + cr;\
00294 outi= 2*inr*ini + ci;
00295
00296 #define Z_Z2_C_ZYKLUS(outr,outi,inr,ini, Z)\
00297 Z_Z2_C(outr,outi,inr,ini)\
00298 if(use_zyklus){\
00299 if(Z && fabs(mb->zyklus[i>>1][0]-outr)+fabs(mb->zyklus[i>>1][1]-outi) <= epsilon)\
00300 break;\
00301 }\
00302 mb->zyklus[i][0]= outr;\
00303 mb->zyklus[i][1]= outi;\
00304
00305
00306
00307 for(i=0; i<mb->maxiter-8; i++){
00308 double t;
00309 Z_Z2_C_ZYKLUS(t, zi, zr, zi, 0)
00310 i++;
00311 Z_Z2_C_ZYKLUS(zr, zi, t, zi, 1)
00312 i++;
00313 Z_Z2_C_ZYKLUS(t, zi, zr, zi, 0)
00314 i++;
00315 Z_Z2_C_ZYKLUS(zr, zi, t, zi, 1)
00316 i++;
00317 Z_Z2_C_ZYKLUS(t, zi, zr, zi, 0)
00318 i++;
00319 Z_Z2_C_ZYKLUS(zr, zi, t, zi, 1)
00320 i++;
00321 Z_Z2_C_ZYKLUS(t, zi, zr, zi, 0)
00322 i++;
00323 Z_Z2_C_ZYKLUS(zr, zi, t, zi, 1)
00324 if(zr*zr + zi*zi > mb->bailout){
00325 i-= FFMIN(7, i);
00326 for(; i<mb->maxiter; i++){
00327 zr= mb->zyklus[i][0];
00328 zi= mb->zyklus[i][1];
00329 if(zr*zr + zi*zi > mb->bailout){
00330 switch(mb->outer){
00331 case ITERATION_COUNT: zr = i; break;
00332 case NORMALIZED_ITERATION_COUNT: zr= i + log2(log(mb->bailout) / log(zr*zr + zi*zi)); break;
00333 }
00334 c= lrintf((sin(zr)+1)*127) + lrintf((sin(zr/1.234)+1)*127)*256*256 + lrintf((sin(zr/100)+1)*127)*256;
00335 break;
00336 }
00337 }
00338 break;
00339 }
00340 }
00341 if(!c){
00342 if(mb->inner==PERIOD){
00343 int j;
00344 for(j=i-1; j; j--)
00345 if(SQR(mb->zyklus[j][0]-zr) + SQR(mb->zyklus[j][1]-zi) < epsilon*epsilon*10)
00346 break;
00347 if(j){
00348 c= i-j;
00349 c= ((c<<5)&0xE0) + ((c<<16)&0xE000) + ((c<<27)&0xE00000);
00350 }
00351 }else if(mb->inner==CONVTIME){
00352 c= floor(i*255.0/mb->maxiter+dv)*0x010101;
00353 } else if(mb->inner==MINCOL){
00354 int j;
00355 double closest=9999;
00356 int closest_index=0;
00357 for(j=i-1; j>=0; j--)
00358 if(SQR(mb->zyklus[j][0]) + SQR(mb->zyklus[j][1]) < closest){
00359 closest= SQR(mb->zyklus[j][0]) + SQR(mb->zyklus[j][1]);
00360 closest_index= j;
00361 }
00362 closest = sqrt(closest);
00363 c= lrintf((mb->zyklus[closest_index][0]/closest+1)*127+dv) + lrintf((mb->zyklus[closest_index][1]/closest+1)*127+dv)*256;
00364 }
00365 }
00366 c |= 0xFF000000;
00367 color[x + y*linesize]= c;
00368 if(next_cidx < mb->cache_allocated){
00369 mb->next_cache[next_cidx ].p[0]= cr;
00370 mb->next_cache[next_cidx ].p[1]= ci;
00371 mb->next_cache[next_cidx++].val = c;
00372 }
00373 }
00374 fill_from_cache(ctx, NULL, &in_cidx, &next_cidx, ci + scale/2, scale);
00375 }
00376 FFSWAP(void*, mb->next_cache, mb->point_cache);
00377 mb->cache_used = next_cidx;
00378 if(mb->cache_used == mb->cache_allocated)
00379 av_log(0, AV_LOG_INFO, "Mandelbrot cache is too small!\n");
00380 }
00381
00382 static int request_frame(AVFilterLink *link)
00383 {
00384 MBContext *mb = link->src->priv;
00385 AVFilterBufferRef *picref = ff_get_video_buffer(link, AV_PERM_WRITE, mb->w, mb->h);
00386 picref->video->sample_aspect_ratio = (AVRational) {1, 1};
00387 picref->pts = mb->pts++;
00388 picref->pos = -1;
00389
00390 ff_start_frame(link, avfilter_ref_buffer(picref, ~0));
00391 draw_mandelbrot(link->src, (uint32_t*)picref->data[0], picref->linesize[0]/4, picref->pts);
00392 ff_draw_slice(link, 0, mb->h, 1);
00393 ff_end_frame(link);
00394 avfilter_unref_buffer(picref);
00395
00396 return 0;
00397 }
00398
00399 AVFilter avfilter_vsrc_mandelbrot = {
00400 .name = "mandelbrot",
00401 .description = NULL_IF_CONFIG_SMALL("Render a Mandelbrot fractal."),
00402
00403 .priv_size = sizeof(MBContext),
00404 .init = init,
00405 .uninit = uninit,
00406
00407 .query_formats = query_formats,
00408
00409 .inputs = (const AVFilterPad[]) {{ .name = NULL}},
00410
00411 .outputs = (const AVFilterPad[]) {{ .name = "default",
00412 .type = AVMEDIA_TYPE_VIDEO,
00413 .request_frame = request_frame,
00414 .config_props = config_props },
00415 { .name = NULL}},
00416 };
