yading@11: /*
yading@11:  * Copyright (c) 2011 Michael Niedermayer
yading@11:  *
yading@11:  * This file is part of FFmpeg.
yading@11:  *
yading@11:  * FFmpeg is free software; you can redistribute it and/or
yading@11:  * modify it under the terms of the GNU Lesser General Public
yading@11:  * License as published by the Free Software Foundation; either
yading@11:  * version 2.1 of the License, or (at your option) any later version.
yading@11:  *
yading@11:  * FFmpeg is distributed in the hope that it will be useful,
yading@11:  * but WITHOUT ANY WARRANTY; without even the implied warranty of
yading@11:  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
yading@11:  * Lesser General Public License for more details.
yading@11:  *
yading@11:  * You should have received a copy of the GNU Lesser General Public
yading@11:  * License along with FFmpeg; if not, write to the Free Software
yading@11:  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
yading@11:  *
yading@11:  * The vsrc_color filter from Stefano Sabatini was used as template to create
yading@11:  * this
yading@11:  */
yading@11: 
yading@11: /**
yading@11:  * @file
yading@11:  * Mandelbrot fraktal renderer
yading@11:  */
yading@11: 
yading@11: #include "avfilter.h"
yading@11: #include "formats.h"
yading@11: #include "video.h"
yading@11: #include "internal.h"
yading@11: #include "libavutil/imgutils.h"
yading@11: #include "libavutil/opt.h"
yading@11: #include "libavutil/parseutils.h"
yading@11: #include <float.h>
yading@11: #include <math.h>
yading@11: 
yading@11: #define SQR(a) ((a)*(a))
yading@11: 
yading@11: enum Outer{
yading@11:     ITERATION_COUNT,
yading@11:     NORMALIZED_ITERATION_COUNT,
yading@11:     WHITE,
yading@11:     OUTZ,
yading@11: };
yading@11: 
yading@11: enum Inner{
yading@11:     BLACK,
yading@11:     PERIOD,
yading@11:     CONVTIME,
yading@11:     MINCOL,
yading@11: };
yading@11: 
yading@11: typedef struct Point {
yading@11:     double p[2];
yading@11:     uint32_t val;
yading@11: } Point;
yading@11: 
yading@11: typedef struct {
yading@11:     const AVClass *class;
yading@11:     int w, h;
yading@11:     AVRational frame_rate;
yading@11:     uint64_t pts;
yading@11:     int maxiter;
yading@11:     double start_x;
yading@11:     double start_y;
yading@11:     double start_scale;
yading@11:     double end_scale;
yading@11:     double end_pts;
yading@11:     double bailout;
yading@11:     enum Outer outer;
yading@11:     enum Inner inner;
yading@11:     int cache_allocated;
yading@11:     int cache_used;
yading@11:     Point *point_cache;
yading@11:     Point *next_cache;
yading@11:     double (*zyklus)[2];
yading@11:     uint32_t dither;
yading@11: 
yading@11:     double morphxf;
yading@11:     double morphyf;
yading@11:     double morphamp;
yading@11: } MBContext;
yading@11: 
yading@11: #define OFFSET(x) offsetof(MBContext, x)
yading@11: #define FLAGS AV_OPT_FLAG_VIDEO_PARAM|AV_OPT_FLAG_FILTERING_PARAM
yading@11: 
yading@11: static const AVOption mandelbrot_options[] = {
yading@11:     {"size",        "set frame size",                OFFSET(w),       AV_OPT_TYPE_IMAGE_SIZE, {.str="640x480"},  CHAR_MIN, CHAR_MAX, FLAGS },
yading@11:     {"s",           "set frame size",                OFFSET(w),       AV_OPT_TYPE_IMAGE_SIZE, {.str="640x480"},  CHAR_MIN, CHAR_MAX, FLAGS },
yading@11:     {"rate",        "set frame rate",                OFFSET(frame_rate), AV_OPT_TYPE_VIDEO_RATE, {.str="25"},  CHAR_MIN, CHAR_MAX, FLAGS },
yading@11:     {"r",           "set frame rate",                OFFSET(frame_rate), AV_OPT_TYPE_VIDEO_RATE, {.str="25"},  CHAR_MIN, CHAR_MAX, FLAGS },
yading@11:     {"maxiter",     "set max iterations number",     OFFSET(maxiter), AV_OPT_TYPE_INT,        {.i64=7189},  1,        INT_MAX, FLAGS },
yading@11:     {"start_x",     "set the initial x position",    OFFSET(start_x), AV_OPT_TYPE_DOUBLE,     {.dbl=-0.743643887037158704752191506114774}, -100, 100, FLAGS },
yading@11:     {"start_y",     "set the initial y position",    OFFSET(start_y), AV_OPT_TYPE_DOUBLE,     {.dbl=-0.131825904205311970493132056385139}, -100, 100, FLAGS },
yading@11:     {"start_scale", "set the initial scale value",   OFFSET(start_scale), AV_OPT_TYPE_DOUBLE, {.dbl=3.0},  0, FLT_MAX, FLAGS },
yading@11:     {"end_scale",   "set the terminal scale value",  OFFSET(end_scale), AV_OPT_TYPE_DOUBLE,   {.dbl=0.3},  0, FLT_MAX, FLAGS },
yading@11:     {"end_pts",     "set the terminal pts value",    OFFSET(end_pts), AV_OPT_TYPE_DOUBLE,     {.dbl=400},  0, INT64_MAX, FLAGS },
yading@11:     {"bailout",     "set the bailout value",         OFFSET(bailout), AV_OPT_TYPE_DOUBLE,     {.dbl=10},   0, FLT_MAX, FLAGS },
yading@11:     {"morphxf",     "set morph x frequency",         OFFSET(morphxf), AV_OPT_TYPE_DOUBLE,     {.dbl=0.01},   -FLT_MAX, FLT_MAX, FLAGS },
yading@11:     {"morphyf",     "set morph y frequency",         OFFSET(morphyf), AV_OPT_TYPE_DOUBLE,     {.dbl=0.0123}, -FLT_MAX, FLT_MAX, FLAGS },
yading@11:     {"morphamp",    "set morph amplitude",           OFFSET(morphamp), AV_OPT_TYPE_DOUBLE,    {.dbl=0},      -FLT_MAX, FLT_MAX, FLAGS },
yading@11: 
yading@11:     {"outer",       "set outer coloring mode",       OFFSET(outer), AV_OPT_TYPE_INT, {.i64=NORMALIZED_ITERATION_COUNT}, 0, INT_MAX, FLAGS, "outer" },
yading@11:     {"iteration_count", "set iteration count mode",  0, AV_OPT_TYPE_CONST, {.i64=ITERATION_COUNT}, INT_MIN, INT_MAX, FLAGS, "outer" },
yading@11:     {"normalized_iteration_count", "set normalized iteration count mode",   0, AV_OPT_TYPE_CONST, {.i64=NORMALIZED_ITERATION_COUNT}, INT_MIN, INT_MAX, FLAGS, "outer" },
yading@11:     {"white", "set white mode",                      0, AV_OPT_TYPE_CONST, {.i64=WHITE}, INT_MIN, INT_MAX, FLAGS, "outer" },
yading@11:     {"outz",        "set outz mode",                 0, AV_OPT_TYPE_CONST, {.i64=OUTZ}, INT_MIN, INT_MAX, FLAGS, "outer" },
yading@11: 
yading@11:     {"inner",       "set inner coloring mode",       OFFSET(inner), AV_OPT_TYPE_INT, {.i64=MINCOL}, 0, INT_MAX, FLAGS, "inner" },
yading@11:     {"black",       "set black mode",                0, AV_OPT_TYPE_CONST, {.i64=BLACK}, INT_MIN, INT_MAX, FLAGS, "inner"},
yading@11:     {"period",      "set period mode",               0, AV_OPT_TYPE_CONST, {.i64=PERIOD}, INT_MIN, INT_MAX, FLAGS, "inner"},
yading@11:     {"convergence", "show time until convergence",   0, AV_OPT_TYPE_CONST, {.i64=CONVTIME}, INT_MIN, INT_MAX, FLAGS, "inner"},
yading@11:     {"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"},
yading@11: 
yading@11:     {NULL},
yading@11: };
yading@11: 
yading@11: AVFILTER_DEFINE_CLASS(mandelbrot);
yading@11: 
yading@11: static av_cold int init(AVFilterContext *ctx)
yading@11: {
yading@11:     MBContext *mb = ctx->priv;
yading@11: 
yading@11:     mb->bailout *= mb->bailout;
yading@11: 
yading@11:     mb->start_scale /=mb->h;
yading@11:     mb->end_scale /=mb->h;
yading@11: 
yading@11:     mb->cache_allocated = mb->w * mb->h * 3;
yading@11:     mb->cache_used = 0;
yading@11:     mb->point_cache= av_malloc(sizeof(*mb->point_cache)*mb->cache_allocated);
yading@11:     mb-> next_cache= av_malloc(sizeof(*mb-> next_cache)*mb->cache_allocated);
yading@11:     mb-> zyklus    = av_malloc(sizeof(*mb->zyklus) * (mb->maxiter+16));
yading@11: 
yading@11:     return 0;
yading@11: }
yading@11: 
yading@11: static av_cold void uninit(AVFilterContext *ctx)
yading@11: {
yading@11:     MBContext *mb = ctx->priv;
yading@11: 
yading@11:     av_freep(&mb->point_cache);
yading@11:     av_freep(&mb-> next_cache);
yading@11:     av_freep(&mb->zyklus);
yading@11: }
yading@11: 
yading@11: static int query_formats(AVFilterContext *ctx)
yading@11: {
yading@11:     static const enum AVPixelFormat pix_fmts[] = {
yading@11:         AV_PIX_FMT_BGR32,
yading@11:         AV_PIX_FMT_NONE
yading@11:     };
yading@11: 
yading@11:     ff_set_common_formats(ctx, ff_make_format_list(pix_fmts));
yading@11:     return 0;
yading@11: }
yading@11: 
yading@11: static int config_props(AVFilterLink *inlink)
yading@11: {
yading@11:     AVFilterContext *ctx = inlink->src;
yading@11:     MBContext *mb = ctx->priv;
yading@11: 
yading@11:     if (av_image_check_size(mb->w, mb->h, 0, ctx) < 0)
yading@11:         return AVERROR(EINVAL);
yading@11: 
yading@11:     inlink->w = mb->w;
yading@11:     inlink->h = mb->h;
yading@11:     inlink->time_base = av_inv_q(mb->frame_rate);
yading@11: 
yading@11:     return 0;
yading@11: }
yading@11: 
yading@11: static void fill_from_cache(AVFilterContext *ctx, uint32_t *color, int *in_cidx, int *out_cidx, double py, double scale){
yading@11:     MBContext *mb = ctx->priv;
yading@11:     if(mb->morphamp)
yading@11:         return;
yading@11:     for(; *in_cidx < mb->cache_used; (*in_cidx)++){
yading@11:         Point *p= &mb->point_cache[*in_cidx];
yading@11:         int x;
yading@11:         if(p->p[1] > py)
yading@11:             break;
yading@11:         x= round((p->p[0] - mb->start_x) / scale + mb->w/2);
yading@11:         if(x<0 || x >= mb->w)
yading@11:             continue;
yading@11:         if(color) color[x] = p->val;
yading@11:         if(out_cidx && *out_cidx < mb->cache_allocated)
yading@11:             mb->next_cache[(*out_cidx)++]= *p;
yading@11:     }
yading@11: }
yading@11: 
yading@11: static int interpol(MBContext *mb, uint32_t *color, int x, int y, int linesize)
yading@11: {
yading@11:     uint32_t a,b,c,d, i;
yading@11:     uint32_t ipol=0xFF000000;
yading@11:     int dist;
yading@11: 
yading@11:     if(!x || !y || x+1==mb->w || y+1==mb->h)
yading@11:         return 0;
yading@11: 
yading@11:     dist= FFMAX(FFABS(x-(mb->w>>1))*mb->h, FFABS(y-(mb->h>>1))*mb->w);
yading@11: 
yading@11:     if(dist<(mb->w*mb->h>>3))
yading@11:         return 0;
yading@11: 
yading@11:     a=color[(x+1) + (y+0)*linesize];
yading@11:     b=color[(x-1) + (y+1)*linesize];
yading@11:     c=color[(x+0) + (y+1)*linesize];
yading@11:     d=color[(x+1) + (y+1)*linesize];
yading@11: 
yading@11:     if(a&&c){
yading@11:         b= color[(x-1) + (y+0)*linesize];
yading@11:         d= color[(x+0) + (y-1)*linesize];
yading@11:     }else if(b&&d){
yading@11:         a= color[(x+1) + (y-1)*linesize];
yading@11:         c= color[(x-1) + (y-1)*linesize];
yading@11:     }else if(c){
yading@11:         d= color[(x+0) + (y-1)*linesize];
yading@11:         a= color[(x-1) + (y+0)*linesize];
yading@11:         b= color[(x+1) + (y-1)*linesize];
yading@11:     }else if(d){
yading@11:         c= color[(x-1) + (y-1)*linesize];
yading@11:         a= color[(x-1) + (y+0)*linesize];
yading@11:         b= color[(x+1) + (y-1)*linesize];
yading@11:     }else
yading@11:         return 0;
yading@11: 
yading@11:     for(i=0; i<3; i++){
yading@11:         int s= 8*i;
yading@11:         uint8_t ac= a>>s;
yading@11:         uint8_t bc= b>>s;
yading@11:         uint8_t cc= c>>s;
yading@11:         uint8_t dc= d>>s;
yading@11:         int ipolab= (ac + bc);
yading@11:         int ipolcd= (cc + dc);
yading@11:         if(FFABS(ipolab - ipolcd) > 5)
yading@11:             return 0;
yading@11:         if(FFABS(ac-bc)+FFABS(cc-dc) > 20)
yading@11:             return 0;
yading@11:         ipol |= ((ipolab + ipolcd + 2)/4)<<s;
yading@11:     }
yading@11:     color[x + y*linesize]= ipol;
yading@11:     return 1;
yading@11: }
yading@11: 
yading@11: static void draw_mandelbrot(AVFilterContext *ctx, uint32_t *color, int linesize, int64_t pts)
yading@11: {
yading@11:     MBContext *mb = ctx->priv;
yading@11:     int x,y,i, in_cidx=0, next_cidx=0, tmp_cidx;
yading@11:     double scale= mb->start_scale*pow(mb->end_scale/mb->start_scale, pts/mb->end_pts);
yading@11:     int use_zyklus=0;
yading@11:     fill_from_cache(ctx, NULL, &in_cidx, NULL, mb->start_y+scale*(-mb->h/2-0.5), scale);
yading@11:     tmp_cidx= in_cidx;
yading@11:     memset(color, 0, sizeof(*color)*mb->w);
yading@11:     for(y=0; y<mb->h; y++){
yading@11:         int y1= y+1;
yading@11:         const double ci=mb->start_y+scale*(y-mb->h/2);
yading@11:         fill_from_cache(ctx, NULL, &in_cidx, &next_cidx, ci, scale);
yading@11:         if(y1<mb->h){
yading@11:             memset(color+linesize*y1, 0, sizeof(*color)*mb->w);
yading@11:             fill_from_cache(ctx, color+linesize*y1, &tmp_cidx, NULL, ci + 3*scale/2, scale);
yading@11:         }
yading@11: 
yading@11:         for(x=0; x<mb->w; x++){
yading@11:             float av_uninit(epsilon);
yading@11:             const double cr=mb->start_x+scale*(x-mb->w/2);
yading@11:             double zr=cr;
yading@11:             double zi=ci;
yading@11:             uint32_t c=0;
yading@11:             double dv= mb->dither / (double)(1LL<<32);
yading@11:             mb->dither= mb->dither*1664525+1013904223;
yading@11: 
yading@11:             if(color[x + y*linesize] & 0xFF000000)
yading@11:                 continue;
yading@11:             if(!mb->morphamp){
yading@11:                 if(interpol(mb, color, x, y, linesize)){
yading@11:                     if(next_cidx < mb->cache_allocated){
yading@11:                         mb->next_cache[next_cidx  ].p[0]= cr;
yading@11:                         mb->next_cache[next_cidx  ].p[1]= ci;
yading@11:                         mb->next_cache[next_cidx++].val = color[x + y*linesize];
yading@11:                     }
yading@11:                     continue;
yading@11:                 }
yading@11:             }else{
yading@11:                 zr += cos(pts * mb->morphxf) * mb->morphamp;
yading@11:                 zi += sin(pts * mb->morphyf) * mb->morphamp;
yading@11:             }
yading@11: 
yading@11:             use_zyklus= (x==0 || mb->inner!=BLACK ||color[x-1 + y*linesize] == 0xFF000000);
yading@11:             if(use_zyklus)
yading@11:                 epsilon= scale*1*sqrt(SQR(x-mb->w/2) + SQR(y-mb->h/2))/mb->w;
yading@11: 
yading@11: #define Z_Z2_C(outr,outi,inr,ini)\
yading@11:             outr= inr*inr - ini*ini + cr;\
yading@11:             outi= 2*inr*ini + ci;
yading@11: 
yading@11: #define Z_Z2_C_ZYKLUS(outr,outi,inr,ini, Z)\
yading@11:             Z_Z2_C(outr,outi,inr,ini)\
yading@11:             if(use_zyklus){\
yading@11:                 if(Z && fabs(mb->zyklus[i>>1][0]-outr)+fabs(mb->zyklus[i>>1][1]-outi) <= epsilon)\
yading@11:                     break;\
yading@11:             }\
yading@11:             mb->zyklus[i][0]= outr;\
yading@11:             mb->zyklus[i][1]= outi;\
yading@11: 
yading@11: 
yading@11: 
yading@11:             for(i=0; i<mb->maxiter-8; i++){
yading@11:                 double t;
yading@11:                 Z_Z2_C_ZYKLUS(t, zi, zr, zi, 0)
yading@11:                 i++;
yading@11:                 Z_Z2_C_ZYKLUS(zr, zi, t, zi, 1)
yading@11:                 i++;
yading@11:                 Z_Z2_C_ZYKLUS(t, zi, zr, zi, 0)
yading@11:                 i++;
yading@11:                 Z_Z2_C_ZYKLUS(zr, zi, t, zi, 1)
yading@11:                 i++;
yading@11:                 Z_Z2_C_ZYKLUS(t, zi, zr, zi, 0)
yading@11:                 i++;
yading@11:                 Z_Z2_C_ZYKLUS(zr, zi, t, zi, 1)
yading@11:                 i++;
yading@11:                 Z_Z2_C_ZYKLUS(t, zi, zr, zi, 0)
yading@11:                 i++;
yading@11:                 Z_Z2_C_ZYKLUS(zr, zi, t, zi, 1)
yading@11:                 if(zr*zr + zi*zi > mb->bailout){
yading@11:                     i-= FFMIN(7, i);
yading@11:                     for(; i<mb->maxiter; i++){
yading@11:                         zr= mb->zyklus[i][0];
yading@11:                         zi= mb->zyklus[i][1];
yading@11:                         if(zr*zr + zi*zi > mb->bailout){
yading@11:                             switch(mb->outer){
yading@11:                             case            ITERATION_COUNT:
yading@11:                                 zr = i;
yading@11:                                 c = lrintf((sin(zr)+1)*127) + lrintf((sin(zr/1.234)+1)*127)*256*256 + lrintf((sin(zr/100)+1)*127)*256;
yading@11:                                 break;
yading@11:                             case NORMALIZED_ITERATION_COUNT:
yading@11:                                 zr = i + log2(log(mb->bailout) / log(zr*zr + zi*zi));
yading@11:                                 c = lrintf((sin(zr)+1)*127) + lrintf((sin(zr/1.234)+1)*127)*256*256 + lrintf((sin(zr/100)+1)*127)*256;
yading@11:                                 break;
yading@11:                             case                      WHITE:
yading@11:                                 c = 0xFFFFFF;
yading@11:                                 break;
yading@11:                             case                      OUTZ:
yading@11:                                 zr /= mb->bailout;
yading@11:                                 zi /= mb->bailout;
yading@11:                                 c = (((int)(zr*128+128))&0xFF)*256 + (((int)(zi*128+128))&0xFF);
yading@11:                             }
yading@11:                             break;
yading@11:                         }
yading@11:                     }
yading@11:                     break;
yading@11:                 }
yading@11:             }
yading@11:             if(!c){
yading@11:                 if(mb->inner==PERIOD){
yading@11:                 int j;
yading@11:                 for(j=i-1; j; j--)
yading@11:                     if(SQR(mb->zyklus[j][0]-zr) + SQR(mb->zyklus[j][1]-zi) < epsilon*epsilon*10)
yading@11:                         break;
yading@11:                 if(j){
yading@11:                     c= i-j;
yading@11:                     c= ((c<<5)&0xE0) + ((c<<10)&0xE000) + ((c<<15)&0xE00000);
yading@11:                 }
yading@11:                 }else if(mb->inner==CONVTIME){
yading@11:                     c= floor(i*255.0/mb->maxiter+dv)*0x010101;
yading@11:                 } else if(mb->inner==MINCOL){
yading@11:                     int j;
yading@11:                     double closest=9999;
yading@11:                     int closest_index=0;
yading@11:                     for(j=i-1; j>=0; j--)
yading@11:                         if(SQR(mb->zyklus[j][0]) + SQR(mb->zyklus[j][1]) < closest){
yading@11:                             closest= SQR(mb->zyklus[j][0]) + SQR(mb->zyklus[j][1]);
yading@11:                             closest_index= j;
yading@11:                         }
yading@11:                     closest = sqrt(closest);
yading@11:                     c= lrintf((mb->zyklus[closest_index][0]/closest+1)*127+dv) + lrintf((mb->zyklus[closest_index][1]/closest+1)*127+dv)*256;
yading@11:                 }
yading@11:             }
yading@11:             c |= 0xFF000000;
yading@11:             color[x + y*linesize]= c;
yading@11:             if(next_cidx < mb->cache_allocated){
yading@11:                 mb->next_cache[next_cidx  ].p[0]= cr;
yading@11:                 mb->next_cache[next_cidx  ].p[1]= ci;
yading@11:                 mb->next_cache[next_cidx++].val = c;
yading@11:             }
yading@11:         }
yading@11:         fill_from_cache(ctx, NULL, &in_cidx, &next_cidx, ci + scale/2, scale);
yading@11:     }
yading@11:     FFSWAP(void*, mb->next_cache, mb->point_cache);
yading@11:     mb->cache_used = next_cidx;
yading@11:     if(mb->cache_used == mb->cache_allocated)
yading@11:         av_log(ctx, AV_LOG_INFO, "Mandelbrot cache is too small!\n");
yading@11: }
yading@11: 
yading@11: static int request_frame(AVFilterLink *link)
yading@11: {
yading@11:     MBContext *mb = link->src->priv;
yading@11:     AVFrame *picref = ff_get_video_buffer(link, mb->w, mb->h);
yading@11:     if (!picref)
yading@11:         return AVERROR(ENOMEM);
yading@11: 
yading@11:     picref->sample_aspect_ratio = (AVRational) {1, 1};
yading@11:     picref->pts = mb->pts++;
yading@11: 
yading@11:     draw_mandelbrot(link->src, (uint32_t*)picref->data[0], picref->linesize[0]/4, picref->pts);
yading@11:     return ff_filter_frame(link, picref);
yading@11: }
yading@11: 
yading@11: static const AVFilterPad mandelbrot_outputs[] = {
yading@11:     {
yading@11:         .name          = "default",
yading@11:         .type          = AVMEDIA_TYPE_VIDEO,
yading@11:         .request_frame = request_frame,
yading@11:         .config_props  = config_props,
yading@11:     },
yading@11:     { NULL },
yading@11: };
yading@11: 
yading@11: AVFilter avfilter_vsrc_mandelbrot = {
yading@11:     .name        = "mandelbrot",
yading@11:     .description = NULL_IF_CONFIG_SMALL("Render a Mandelbrot fractal."),
yading@11: 
yading@11:     .priv_size = sizeof(MBContext),
yading@11:     .init      = init,
yading@11:     .uninit    = uninit,
yading@11: 
yading@11:     .query_formats = query_formats,
yading@11:     .inputs        = NULL,
yading@11:     .outputs       = mandelbrot_outputs,
yading@11:     .priv_class    = &mandelbrot_class,
yading@11: };