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00029 #include "avfilter.h"
00030 #include "libavutil/imgutils.h"
00031 #include "libavutil/opt.h"
00032 #include "libavutil/parseutils.h"
00033 #include <float.h>
00034 #include <math.h>
00035
00036 #define SQR(a) ((a)*(a))
00037
00038 enum Outer{
00039 ITERATION_COUNT,
00040 NORMALIZED_ITERATION_COUNT,
00041 };
00042
00043 enum Inner{
00044 BLACK,
00045 PERIOD,
00046 CONVTIME,
00047 MINCOL,
00048 };
00049
00050 typedef struct Point {
00051 double p[2];
00052 uint32_t val;
00053 } Point;
00054
00055 typedef struct {
00056 const AVClass *class;
00057 int w, h;
00058 AVRational time_base;
00059 uint64_t pts;
00060 char *size, *rate;
00061 int maxiter;
00062 double start_x;
00063 double start_y;
00064 double start_scale;
00065 double end_scale;
00066 double end_pts;
00067 double bailout;
00068 enum Outer outer;
00069 enum Inner inner;
00070 int cache_allocated;
00071 int cache_used;
00072 Point *point_cache;
00073 Point *next_cache;
00074 double (*zyklus)[2];
00075 uint32_t dither;
00076 } MBContext;
00077
00078 #define OFFSET(x) offsetof(MBContext, x)
00079
00080 static const AVOption mandelbrot_options[] = {
00081 {"size", "set frame size", OFFSET(size), AV_OPT_TYPE_STRING, {.str="640x480"}, CHAR_MIN, CHAR_MAX },
00082 {"s", "set frame size", OFFSET(size), AV_OPT_TYPE_STRING, {.str="640x480"}, CHAR_MIN, CHAR_MAX },
00083 {"rate", "set frame rate", OFFSET(rate), AV_OPT_TYPE_STRING, {.str="25"}, CHAR_MIN, CHAR_MAX },
00084 {"r", "set frame rate", OFFSET(rate), AV_OPT_TYPE_STRING, {.str="25"}, CHAR_MIN, CHAR_MAX },
00085 {"maxiter", "set max iterations number", OFFSET(maxiter), AV_OPT_TYPE_INT, {.dbl=7189}, 1, INT_MAX },
00086 {"start_x", "set the initial x position", OFFSET(start_x), AV_OPT_TYPE_DOUBLE, {.dbl=-0.743643887037158704752191506114774}, -100, 100 },
00087 {"start_y", "set the initial y position", OFFSET(start_y), AV_OPT_TYPE_DOUBLE, {.dbl=-0.131825904205311970493132056385139}, -100, 100 },
00088 {"start_scale", "set the initial scale value", OFFSET(start_scale), AV_OPT_TYPE_DOUBLE, {.dbl=3.0}, 0, FLT_MAX },
00089 {"end_scale", "set the terminal scale value", OFFSET(end_scale), AV_OPT_TYPE_DOUBLE, {.dbl=0.3}, 0, FLT_MAX },
00090 {"end_pts", "set the terminal pts value", OFFSET(end_pts), AV_OPT_TYPE_DOUBLE, {.dbl=400}, 0, INT64_MAX },
00091 {"bailout", "set the bailout value", OFFSET(bailout), AV_OPT_TYPE_DOUBLE, {.dbl=10}, 0, FLT_MAX },
00092
00093 {"outer", "set outer coloring mode", OFFSET(outer), AV_OPT_TYPE_INT, {.dbl=NORMALIZED_ITERATION_COUNT}, 0, INT_MAX, 0, "outer"},
00094 {"iteration_count", "set iteration count mode", 0, AV_OPT_TYPE_CONST, {.dbl=ITERATION_COUNT}, INT_MIN, INT_MAX, 0, "outer" },
00095 {"normalized_iteration_count", "set normalized iteration count mode", 0, AV_OPT_TYPE_CONST, {.dbl=NORMALIZED_ITERATION_COUNT}, INT_MIN, INT_MAX, 0, "outer" },
00096
00097 {"inner", "set inner coloring mode", OFFSET(inner), AV_OPT_TYPE_INT, {.dbl=MINCOL}, 0, INT_MAX, 0, "inner"},
00098 {"black", "set black mode", 0, AV_OPT_TYPE_CONST, {.dbl=BLACK}, INT_MIN, INT_MAX, 0, "inner" },
00099 {"period", "set period mode", 0, AV_OPT_TYPE_CONST, {.dbl=PERIOD}, INT_MIN, INT_MAX, 0, "inner" },
00100 {"convergence", "show time until convergence", 0, AV_OPT_TYPE_CONST, {.dbl=CONVTIME}, INT_MIN, INT_MAX, 0, "inner" },
00101 {"mincol", "color based on point closest to the origin of the iterations", 0, AV_OPT_TYPE_CONST, {.dbl=MINCOL}, INT_MIN, INT_MAX, 0, "inner" },
00102
00103 {NULL},
00104 };
00105
00106 static const char *mandelbrot_get_name(void *ctx)
00107 {
00108 return "mandelbrot";
00109 }
00110
00111 static const AVClass mandelbrot_class = {
00112 "MBContext",
00113 mandelbrot_get_name,
00114 mandelbrot_options
00115 };
00116
00117 static av_cold int init(AVFilterContext *ctx, const char *args, void *opaque)
00118 {
00119 MBContext *mb = ctx->priv;
00120 AVRational rate_q;
00121 int err;
00122
00123 mb->class = &mandelbrot_class;
00124 av_opt_set_defaults(mb);
00125
00126 if ((err = (av_set_options_string(mb, args, "=", ":"))) < 0) {
00127 av_log(ctx, AV_LOG_ERROR, "Error parsing options string: '%s'\n", args);
00128 return err;
00129 }
00130 mb->bailout *= mb->bailout;
00131
00132 if (av_parse_video_size(&mb->w, &mb->h, mb->size) < 0) {
00133 av_log(ctx, AV_LOG_ERROR, "Invalid frame size: %s\n", mb->size);
00134 return AVERROR(EINVAL);
00135 }
00136 mb->start_scale /=mb->h;
00137 mb->end_scale /=mb->h;
00138
00139 if (av_parse_video_rate(&rate_q, mb->rate) < 0 ||
00140 rate_q.den <= 0 || rate_q.num <= 0) {
00141 av_log(ctx, AV_LOG_ERROR, "Invalid frame rate: %s\n", mb->rate);
00142 return AVERROR(EINVAL);
00143 }
00144 mb->time_base.num = rate_q.den;
00145 mb->time_base.den = rate_q.num;
00146
00147 mb->cache_allocated = mb->w * mb->h * 3;
00148 mb->cache_used = 0;
00149 mb->point_cache= av_malloc(sizeof(*mb->point_cache)*mb->cache_allocated);
00150 mb-> next_cache= av_malloc(sizeof(*mb-> next_cache)*mb->cache_allocated);
00151 mb-> zyklus = av_malloc(sizeof(*mb->zyklus) * (mb->maxiter+16));
00152
00153 return 0;
00154 }
00155
00156 static av_cold void uninit(AVFilterContext *ctx)
00157 {
00158 MBContext *mb = ctx->priv;
00159
00160 av_freep(&mb->size);
00161 av_freep(&mb->rate);
00162 av_freep(&mb->point_cache);
00163 av_freep(&mb-> next_cache);
00164 av_freep(&mb->zyklus);
00165 }
00166
00167 static int query_formats(AVFilterContext *ctx)
00168 {
00169 static const enum PixelFormat pix_fmts[] = {
00170 PIX_FMT_BGR32,
00171 PIX_FMT_NONE
00172 };
00173
00174 avfilter_set_common_pixel_formats(ctx, avfilter_make_format_list(pix_fmts));
00175 return 0;
00176 }
00177
00178 static int config_props(AVFilterLink *inlink)
00179 {
00180 AVFilterContext *ctx = inlink->src;
00181 MBContext *mb = ctx->priv;
00182
00183 if (av_image_check_size(mb->w, mb->h, 0, ctx) < 0)
00184 return AVERROR(EINVAL);
00185
00186 inlink->w = mb->w;
00187 inlink->h = mb->h;
00188 inlink->time_base = mb->time_base;
00189
00190 return 0;
00191 }
00192
00193 static void fill_from_cache(AVFilterContext *ctx, uint32_t *color, int *in_cidx, int *out_cidx, double py, double scale){
00194 MBContext *mb = ctx->priv;
00195 for(; *in_cidx < mb->cache_used; (*in_cidx)++){
00196 Point *p= &mb->point_cache[*in_cidx];
00197 int x;
00198 if(p->p[1] > py)
00199 break;
00200 x= round((p->p[0] - mb->start_x) / scale + mb->w/2);
00201 if(x<0 || x >= mb->w)
00202 continue;
00203 if(color) color[x] = p->val;
00204 if(out_cidx && *out_cidx < mb->cache_allocated)
00205 mb->next_cache[(*out_cidx)++]= *p;
00206 }
00207 }
00208
00209 static int interpol(MBContext *mb, uint32_t *color, int x, int y, int linesize)
00210 {
00211 uint32_t a,b,c,d, i;
00212 uint32_t ipol=0xFF000000;
00213 int dist;
00214
00215 if(!x || !y || x+1==mb->w || y+1==mb->h)
00216 return 0;
00217
00218 dist= FFMAX(FFABS(x-(mb->w>>1))*mb->h, FFABS(y-(mb->h>>1))*mb->w);
00219
00220 if(dist<(mb->w*mb->h>>3))
00221 return 0;
00222
00223 a=color[(x+1) + (y+0)*linesize];
00224 b=color[(x-1) + (y+1)*linesize];
00225 c=color[(x+0) + (y+1)*linesize];
00226 d=color[(x+1) + (y+1)*linesize];
00227
00228 if(a&&c){
00229 b= color[(x-1) + (y+0)*linesize];
00230 d= color[(x+0) + (y-1)*linesize];
00231 }else if(b&&d){
00232 a= color[(x+1) + (y-1)*linesize];
00233 c= color[(x-1) + (y-1)*linesize];
00234 }else if(c){
00235 d= color[(x+0) + (y-1)*linesize];
00236 a= color[(x-1) + (y+0)*linesize];
00237 b= color[(x+1) + (y-1)*linesize];
00238 }else if(d){
00239 c= color[(x-1) + (y-1)*linesize];
00240 a= color[(x-1) + (y+0)*linesize];
00241 b= color[(x+1) + (y-1)*linesize];
00242 }else
00243 return 0;
00244
00245 for(i=0; i<3; i++){
00246 int s= 8*i;
00247 uint8_t ac= a>>s;
00248 uint8_t bc= b>>s;
00249 uint8_t cc= c>>s;
00250 uint8_t dc= d>>s;
00251 int ipolab= (ac + bc);
00252 int ipolcd= (cc + dc);
00253 if(FFABS(ipolab - ipolcd) > 5)
00254 return 0;
00255 if(FFABS(ac-bc)+FFABS(cc-dc) > 20)
00256 return 0;
00257 ipol |= ((ipolab + ipolcd + 2)/4)<<s;
00258 }
00259 color[x + y*linesize]= ipol;
00260 return 1;
00261 }
00262
00263 static void draw_mandelbrot(AVFilterContext *ctx, uint32_t *color, int linesize, int64_t pts)
00264 {
00265 MBContext *mb = ctx->priv;
00266 int x,y,i, in_cidx=0, next_cidx=0, tmp_cidx;
00267 double scale= mb->start_scale*pow(mb->end_scale/mb->start_scale, pts/mb->end_pts);
00268 int use_zyklus=0;
00269 fill_from_cache(ctx, NULL, &in_cidx, NULL, mb->start_y+scale*(-mb->h/2-0.5), scale);
00270 tmp_cidx= in_cidx;
00271 memset(color, 0, sizeof(*color)*mb->w);
00272 for(y=0; y<mb->h; y++){
00273 int y1= y+1;
00274 const double ci=mb->start_y+scale*(y-mb->h/2);
00275 fill_from_cache(ctx, NULL, &in_cidx, &next_cidx, ci, scale);
00276 if(y1<mb->h){
00277 memset(color+linesize*y1, 0, sizeof(*color)*mb->w);
00278 fill_from_cache(ctx, color+linesize*y1, &tmp_cidx, NULL, ci + 3*scale/2, scale);
00279 }
00280
00281 for(x=0; x<mb->w; x++){
00282 float av_uninit(epsilon);
00283 const double cr=mb->start_x+scale*(x-mb->w/2);
00284 double zr=cr;
00285 double zi=ci;
00286 uint32_t c=0;
00287 double dv= mb->dither / (double)(1LL<<32);
00288 mb->dither= mb->dither*1664525+1013904223;
00289
00290 if(color[x + y*linesize] & 0xFF000000)
00291 continue;
00292 if(interpol(mb, color, x, y, linesize)){
00293 if(next_cidx < mb->cache_allocated){
00294 mb->next_cache[next_cidx ].p[0]= cr;
00295 mb->next_cache[next_cidx ].p[1]= ci;
00296 mb->next_cache[next_cidx++].val = color[x + y*linesize];
00297 }
00298 continue;
00299 }
00300
00301 use_zyklus= (x==0 || mb->inner!=BLACK ||color[x-1 + y*linesize] == 0xFF000000);
00302 if(use_zyklus)
00303 epsilon= scale*1*sqrt(SQR(x-mb->w/2) + SQR(y-mb->h/2))/mb->w;
00304
00305 #define Z_Z2_C(outr,outi,inr,ini)\
00306 outr= inr*inr - ini*ini + cr;\
00307 outi= 2*inr*ini + ci;
00308
00309 #define Z_Z2_C_ZYKLUS(outr,outi,inr,ini, Z)\
00310 Z_Z2_C(outr,outi,inr,ini)\
00311 if(use_zyklus){\
00312 if(Z && fabs(mb->zyklus[i>>1][0]-outr)+fabs(mb->zyklus[i>>1][1]-outi) <= epsilon)\
00313 break;\
00314 }\
00315 mb->zyklus[i][0]= outr;\
00316 mb->zyklus[i][1]= outi;\
00317
00318
00319
00320 for(i=0; i<mb->maxiter-8; i++){
00321 double t;
00322 Z_Z2_C_ZYKLUS(t, zi, zr, zi, 0)
00323 i++;
00324 Z_Z2_C_ZYKLUS(zr, zi, t, zi, 1)
00325 i++;
00326 Z_Z2_C_ZYKLUS(t, zi, zr, zi, 0)
00327 i++;
00328 Z_Z2_C_ZYKLUS(zr, zi, t, zi, 1)
00329 i++;
00330 Z_Z2_C_ZYKLUS(t, zi, zr, zi, 0)
00331 i++;
00332 Z_Z2_C_ZYKLUS(zr, zi, t, zi, 1)
00333 i++;
00334 Z_Z2_C_ZYKLUS(t, zi, zr, zi, 0)
00335 i++;
00336 Z_Z2_C_ZYKLUS(zr, zi, t, zi, 1)
00337 if(zr*zr + zi*zi > mb->bailout){
00338 i-= FFMIN(7, i);
00339 for(; i<mb->maxiter; i++){
00340 zr= mb->zyklus[i][0];
00341 zi= mb->zyklus[i][1];
00342 if(zr*zr + zi*zi > mb->bailout){
00343 switch(mb->outer){
00344 case ITERATION_COUNT: zr = i; break;
00345 case NORMALIZED_ITERATION_COUNT: zr= i + log2(log(mb->bailout) / log(zr*zr + zi*zi)); break;
00346 }
00347 c= lrintf((sin(zr)+1)*127) + lrintf((sin(zr/1.234)+1)*127)*256*256 + lrintf((sin(zr/100)+1)*127)*256;
00348 break;
00349 }
00350 }
00351 break;
00352 }
00353 }
00354 if(!c){
00355 if(mb->inner==PERIOD){
00356 int j;
00357 for(j=i-1; j; j--)
00358 if(SQR(mb->zyklus[j][0]-zr) + SQR(mb->zyklus[j][1]-zi) < epsilon*epsilon*10)
00359 break;
00360 if(j){
00361 c= i-j;
00362 c= ((c<<5)&0xE0) + ((c<<16)&0xE000) + ((c<<27)&0xE00000);
00363 }
00364 }else if(mb->inner==CONVTIME){
00365 c= floor(i*255.0/mb->maxiter+dv)*0x010101;
00366 } else if(mb->inner==MINCOL){
00367 int j;
00368 double closest=9999;
00369 int closest_index=0;
00370 for(j=i-1; j>=0; j--)
00371 if(SQR(mb->zyklus[j][0]) + SQR(mb->zyklus[j][1]) < closest){
00372 closest= SQR(mb->zyklus[j][0]) + SQR(mb->zyklus[j][1]);
00373 closest_index= j;
00374 }
00375 closest = sqrt(closest);
00376 c= lrintf((mb->zyklus[closest_index][0]/closest+1)*127+dv) + lrintf((mb->zyklus[closest_index][1]/closest+1)*127+dv)*256;
00377 }
00378 }
00379 c |= 0xFF000000;
00380 color[x + y*linesize]= c;
00381 if(next_cidx < mb->cache_allocated){
00382 mb->next_cache[next_cidx ].p[0]= cr;
00383 mb->next_cache[next_cidx ].p[1]= ci;
00384 mb->next_cache[next_cidx++].val = c;
00385 }
00386 }
00387 fill_from_cache(ctx, NULL, &in_cidx, &next_cidx, ci + scale/2, scale);
00388 }
00389 FFSWAP(void*, mb->next_cache, mb->point_cache);
00390 mb->cache_used = next_cidx;
00391 if(mb->cache_used == mb->cache_allocated)
00392 av_log(0, AV_LOG_INFO, "Mandelbrot cache is too small!\n");
00393 }
00394
00395 static int request_frame(AVFilterLink *link)
00396 {
00397 MBContext *mb = link->src->priv;
00398 AVFilterBufferRef *picref = avfilter_get_video_buffer(link, AV_PERM_WRITE, mb->w, mb->h);
00399 picref->video->sample_aspect_ratio = (AVRational) {1, 1};
00400 picref->pts = mb->pts++;
00401 picref->pos = -1;
00402
00403 avfilter_start_frame(link, avfilter_ref_buffer(picref, ~0));
00404 draw_mandelbrot(link->src, (uint32_t*)picref->data[0], picref->linesize[0]/4, picref->pts);
00405 avfilter_draw_slice(link, 0, mb->h, 1);
00406 avfilter_end_frame(link);
00407 avfilter_unref_buffer(picref);
00408
00409 return 0;
00410 }
00411
00412 AVFilter avfilter_vsrc_mandelbrot = {
00413 .name = "mandelbrot",
00414 .description = NULL_IF_CONFIG_SMALL("Render a Mandelbrot fractal."),
00415
00416 .priv_size = sizeof(MBContext),
00417 .init = init,
00418 .uninit = uninit,
00419
00420 .query_formats = query_formats,
00421
00422 .inputs = (const AVFilterPad[]) {{ .name = NULL}},
00423
00424 .outputs = (const AVFilterPad[]) {{ .name = "default",
00425 .type = AVMEDIA_TYPE_VIDEO,
00426 .request_frame = request_frame,
00427 .config_props = config_props },
00428 { .name = NULL}},
00429 };
