FFmpeg
vsrc_mandelbrot.c
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1 /*
2  * Copyright (c) 2011 Michael Niedermayer
3  *
4  * This file is part of FFmpeg.
5  *
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.
10  *
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.
15  *
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
19  *
20  * The vsrc_color filter from Stefano Sabatini was used as template to create
21  * this
22  */
23 
24 /**
25  * @file
26  * Mandelbrot fractal renderer
27  */
28 
29 #include "avfilter.h"
30 #include "formats.h"
31 #include "video.h"
32 #include "internal.h"
33 #include "libavutil/imgutils.h"
34 #include "libavutil/opt.h"
35 #include "libavutil/parseutils.h"
36 #include <float.h>
37 #include <math.h>
38 
39 #define SQR(a) ((a)*(a))
40 
41 enum Outer{
46 };
47 
48 enum Inner{
53 };
54 
55 typedef struct Point {
56  double p[2];
57  uint32_t val;
58 } Point;
59 
60 typedef struct MBContext {
61  const AVClass *class;
62  int w, h;
64  uint64_t pts;
65  int maxiter;
66  double start_x;
67  double start_y;
68  double start_scale;
69  double end_scale;
70  double end_pts;
71  double bailout;
72  int outer;
73  int inner;
78  double (*zyklus)[2];
79  uint32_t dither;
80 
81  double morphxf;
82  double morphyf;
83  double morphamp;
84 } MBContext;
85 
86 #define OFFSET(x) offsetof(MBContext, x)
87 #define FLAGS AV_OPT_FLAG_VIDEO_PARAM|AV_OPT_FLAG_FILTERING_PARAM
88 
89 static const AVOption mandelbrot_options[] = {
90  {"size", "set frame size", OFFSET(w), AV_OPT_TYPE_IMAGE_SIZE, {.str="640x480"}, 0, 0, FLAGS },
91  {"s", "set frame size", OFFSET(w), AV_OPT_TYPE_IMAGE_SIZE, {.str="640x480"}, 0, 0, FLAGS },
92  {"rate", "set frame rate", OFFSET(frame_rate), AV_OPT_TYPE_VIDEO_RATE, {.str="25"}, 0, INT_MAX, FLAGS },
93  {"r", "set frame rate", OFFSET(frame_rate), AV_OPT_TYPE_VIDEO_RATE, {.str="25"}, 0, INT_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 },
104 
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" },
110 
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"},
116 
117  {NULL},
118 };
119 
120 AVFILTER_DEFINE_CLASS(mandelbrot);
121 
123 {
124  MBContext *s = ctx->priv;
125 
126  s->bailout *= s->bailout;
127 
128  s->start_scale /=s->h;
129  s->end_scale /=s->h;
130 
131  s->cache_allocated = s->w * s->h * 3;
132  s->cache_used = 0;
133  s->point_cache= av_malloc_array(s->cache_allocated, sizeof(*s->point_cache));
134  s-> next_cache= av_malloc_array(s->cache_allocated, sizeof(*s-> next_cache));
135  s-> zyklus = av_malloc_array(s->maxiter + 16, sizeof(*s->zyklus));
136 
137  return 0;
138 }
139 
141 {
142  MBContext *s = ctx->priv;
143 
144  av_freep(&s->point_cache);
145  av_freep(&s-> next_cache);
146  av_freep(&s->zyklus);
147 }
148 
150 {
151  AVFilterContext *ctx = inlink->src;
152  MBContext *s = ctx->priv;
153 
154  if (av_image_check_size(s->w, s->h, 0, ctx) < 0)
155  return AVERROR(EINVAL);
156 
157  inlink->w = s->w;
158  inlink->h = s->h;
159  inlink->time_base = av_inv_q(s->frame_rate);
160 
161  return 0;
162 }
163 
164 static void fill_from_cache(AVFilterContext *ctx, uint32_t *color, int *in_cidx, int *out_cidx, double py, double scale){
165  MBContext *s = ctx->priv;
166  if(s->morphamp)
167  return;
168  for(; *in_cidx < s->cache_used; (*in_cidx)++){
169  Point *p= &s->point_cache[*in_cidx];
170  int x;
171  if(p->p[1] > py)
172  break;
173  x= lrint((p->p[0] - s->start_x) / scale + s->w/2);
174  if(x<0 || x >= s->w)
175  continue;
176  if(color) color[x] = p->val;
177  if(out_cidx && *out_cidx < s->cache_allocated)
178  s->next_cache[(*out_cidx)++]= *p;
179  }
180 }
181 
182 static int interpol(MBContext *s, uint32_t *color, int x, int y, int linesize)
183 {
184  uint32_t a,b,c,d, i;
185  uint32_t ipol=0xFF000000;
186  int dist;
187 
188  if(!x || !y || x+1==s->w || y+1==s->h)
189  return 0;
190 
191  dist= FFMAX(FFABS(x-(s->w>>1))*s->h, FFABS(y-(s->h>>1))*s->w);
192 
193  if(dist<(s->w*s->h>>3))
194  return 0;
195 
196  a=color[(x+1) + (y+0)*linesize];
197  b=color[(x-1) + (y+1)*linesize];
198  c=color[(x+0) + (y+1)*linesize];
199  d=color[(x+1) + (y+1)*linesize];
200 
201  if(a&&c){
202  b= color[(x-1) + (y+0)*linesize];
203  d= color[(x+0) + (y-1)*linesize];
204  }else if(b&&d){
205  a= color[(x+1) + (y-1)*linesize];
206  c= color[(x-1) + (y-1)*linesize];
207  }else if(c){
208  d= color[(x+0) + (y-1)*linesize];
209  a= color[(x-1) + (y+0)*linesize];
210  b= color[(x+1) + (y-1)*linesize];
211  }else if(d){
212  c= color[(x-1) + (y-1)*linesize];
213  a= color[(x-1) + (y+0)*linesize];
214  b= color[(x+1) + (y-1)*linesize];
215  }else
216  return 0;
217 
218  for(i=0; i<3; i++){
219  int s= 8*i;
220  uint8_t ac= a>>s;
221  uint8_t bc= b>>s;
222  uint8_t cc= c>>s;
223  uint8_t dc= d>>s;
224  int ipolab= (ac + bc);
225  int ipolcd= (cc + dc);
226  if(FFABS(ipolab - ipolcd) > 5)
227  return 0;
228  if(FFABS(ac-bc)+FFABS(cc-dc) > 20)
229  return 0;
230  ipol |= ((ipolab + ipolcd + 2)/4)<<s;
231  }
232  color[x + y*linesize]= ipol;
233  return 1;
234 }
235 
236 static void draw_mandelbrot(AVFilterContext *ctx, uint32_t *color, int linesize, int64_t pts)
237 {
238  MBContext *s = ctx->priv;
239  int x,y,i, in_cidx=0, next_cidx=0, tmp_cidx;
240  double scale= s->start_scale*pow(s->end_scale/s->start_scale, pts/s->end_pts);
241  int use_zyklus=0;
242  fill_from_cache(ctx, NULL, &in_cidx, NULL, s->start_y+scale*(-s->h/2-0.5), scale);
243  tmp_cidx= in_cidx;
244  memset(color, 0, sizeof(*color)*s->w);
245  for(y=0; y<s->h; y++){
246  int y1= y+1;
247  const double ci=s->start_y+scale*(y-s->h/2);
248  fill_from_cache(ctx, NULL, &in_cidx, &next_cidx, ci, scale);
249  if(y1<s->h){
250  memset(color+linesize*y1, 0, sizeof(*color)*s->w);
251  fill_from_cache(ctx, color+linesize*y1, &tmp_cidx, NULL, ci + 3*scale/2, scale);
252  }
253 
254  for(x=0; x<s->w; x++){
255  float av_uninit(epsilon);
256  const double cr=s->start_x+scale*(x-s->w/2);
257  double zr=cr;
258  double zi=ci;
259  uint32_t c=0;
260  double dv= s->dither / (double)(1LL<<32);
261  s->dither= s->dither*1664525+1013904223;
262 
263  if(color[x + y*linesize] & 0xFF000000)
264  continue;
265  if(!s->morphamp){
266  if(interpol(s, color, x, y, linesize)){
267  if(next_cidx < s->cache_allocated){
268  s->next_cache[next_cidx ].p[0]= cr;
269  s->next_cache[next_cidx ].p[1]= ci;
270  s->next_cache[next_cidx++].val = color[x + y*linesize];
271  }
272  continue;
273  }
274  }else{
275  zr += cos(pts * s->morphxf) * s->morphamp;
276  zi += sin(pts * s->morphyf) * s->morphamp;
277  }
278 
279  use_zyklus= (x==0 || s->inner!=BLACK ||color[x-1 + y*linesize] == 0xFF000000);
280  if(use_zyklus)
281  epsilon= scale*(abs(x-s->w/2) + abs(y-s->h/2))/s->w;
282 
283 #define Z_Z2_C(outr,outi,inr,ini)\
284  outr= inr*inr - ini*ini + cr;\
285  outi= 2*inr*ini + ci;
286 
287 #define Z_Z2_C_ZYKLUS(outr,outi,inr,ini, Z)\
288  Z_Z2_C(outr,outi,inr,ini)\
289  if(use_zyklus){\
290  if(Z && fabs(s->zyklus[i>>1][0]-outr)+fabs(s->zyklus[i>>1][1]-outi) <= epsilon)\
291  break;\
292  }\
293  s->zyklus[i][0]= outr;\
294  s->zyklus[i][1]= outi;\
295 
296 
297 
298  for(i=0; i<s->maxiter-8; i++){
299  double t;
300  Z_Z2_C_ZYKLUS(t, zi, zr, zi, 0)
301  i++;
302  Z_Z2_C_ZYKLUS(zr, zi, t, zi, 1)
303  i++;
304  Z_Z2_C_ZYKLUS(t, zi, zr, zi, 0)
305  i++;
306  Z_Z2_C_ZYKLUS(zr, zi, t, zi, 1)
307  i++;
308  Z_Z2_C_ZYKLUS(t, zi, zr, zi, 0)
309  i++;
310  Z_Z2_C_ZYKLUS(zr, zi, t, zi, 1)
311  i++;
312  Z_Z2_C_ZYKLUS(t, zi, zr, zi, 0)
313  i++;
314  Z_Z2_C_ZYKLUS(zr, zi, t, zi, 1)
315  if(zr*zr + zi*zi > s->bailout){
316  i-= FFMIN(7, i);
317  for(; i<s->maxiter; i++){
318  zr= s->zyklus[i][0];
319  zi= s->zyklus[i][1];
320  if(zr*zr + zi*zi > s->bailout){
321  switch(s->outer){
322  case ITERATION_COUNT:
323  zr = i;
324  c = lrintf((sinf(zr)+1)*127) + lrintf((sinf(zr/1.234)+1)*127)*256*256 + lrintf((sinf(zr/100)+1)*127)*256;
325  break;
327  zr = i + log2(log(s->bailout) / log(zr*zr + zi*zi));
328  c = lrintf((sinf(zr)+1)*127) + lrintf((sinf(zr/1.234)+1)*127)*256*256 + lrintf((sinf(zr/100)+1)*127)*256;
329  break;
330  case WHITE:
331  c = 0xFFFFFF;
332  break;
333  case OUTZ:
334  zr /= s->bailout;
335  zi /= s->bailout;
336  c = (((int)(zr*128+128))&0xFF)*256 + (((int)(zi*128+128))&0xFF);
337  }
338  break;
339  }
340  }
341  break;
342  }
343  }
344  if(!c){
345  if(s->inner==PERIOD){
346  int j;
347  for(j=i-1; j; j--)
348  if(SQR(s->zyklus[j][0]-zr) + SQR(s->zyklus[j][1]-zi) < epsilon*epsilon*10)
349  break;
350  if(j){
351  c= i-j;
352  c= ((c<<5)&0xE0) + ((c<<10)&0xE000) + ((c<<15)&0xE00000);
353  }
354  }else if(s->inner==CONVTIME){
355  c= floor(i*255.0/s->maxiter+dv)*0x010101;
356  } else if(s->inner==MINCOL){
357  int j;
358  double closest=9999;
359  int closest_index=0;
360  for(j=i-1; j>=0; j--)
361  if(SQR(s->zyklus[j][0]) + SQR(s->zyklus[j][1]) < closest){
362  closest= SQR(s->zyklus[j][0]) + SQR(s->zyklus[j][1]);
363  closest_index= j;
364  }
365  closest = sqrt(closest);
366  c= lrintf((s->zyklus[closest_index][0]/closest+1)*127+dv) + lrintf((s->zyklus[closest_index][1]/closest+1)*127+dv)*256;
367  }
368  }
369  c |= 0xFF000000;
370  color[x + y*linesize]= c;
371  if(next_cidx < s->cache_allocated){
372  s->next_cache[next_cidx ].p[0]= cr;
373  s->next_cache[next_cidx ].p[1]= ci;
374  s->next_cache[next_cidx++].val = c;
375  }
376  }
377  fill_from_cache(ctx, NULL, &in_cidx, &next_cidx, ci + scale/2, scale);
378  }
379  FFSWAP(void*, s->next_cache, s->point_cache);
380  s->cache_used = next_cidx;
381  if(s->cache_used == s->cache_allocated)
382  av_log(ctx, AV_LOG_INFO, "Mandelbrot cache is too small!\n");
383 }
384 
386 {
387  MBContext *s = link->src->priv;
388  AVFrame *picref = ff_get_video_buffer(link, s->w, s->h);
389  if (!picref)
390  return AVERROR(ENOMEM);
391 
392  picref->sample_aspect_ratio = (AVRational) {1, 1};
393  picref->pts = s->pts++;
394 
395  draw_mandelbrot(link->src, (uint32_t*)picref->data[0], picref->linesize[0]/4, picref->pts);
396  return ff_filter_frame(link, picref);
397 }
398 
399 static const AVFilterPad mandelbrot_outputs[] = {
400  {
401  .name = "default",
402  .type = AVMEDIA_TYPE_VIDEO,
403  .request_frame = request_frame,
404  .config_props = config_props,
405  },
406 };
407 
409  .name = "mandelbrot",
410  .description = NULL_IF_CONFIG_SMALL("Render a Mandelbrot fractal."),
411  .priv_size = sizeof(MBContext),
412  .priv_class = &mandelbrot_class,
413  .init = init,
414  .uninit = uninit,
415  .inputs = NULL,
418 };
draw_mandelbrot
static void draw_mandelbrot(AVFilterContext *ctx, uint32_t *color, int linesize, int64_t pts)
Definition: vsrc_mandelbrot.c:236
ff_get_video_buffer
AVFrame * ff_get_video_buffer(AVFilterLink *link, int w, int h)
Request a picture buffer with a specific set of permissions.
Definition: video.c:98
MBContext::end_scale
double end_scale
Definition: vsrc_mandelbrot.c:69
interpol
static int interpol(MBContext *s, uint32_t *color, int x, int y, int linesize)
Definition: vsrc_mandelbrot.c:182
init
static av_cold int init(AVFilterContext *ctx)
Definition: vsrc_mandelbrot.c:122
NORMALIZED_ITERATION_COUNT
@ NORMALIZED_ITERATION_COUNT
Definition: vsrc_mandelbrot.c:43
Inner
Inner
Definition: vsrc_mandelbrot.c:48
AVERROR
Filter the word “frame” indicates either a video frame or a group of audio as stored in an AVFrame structure Format for each input and each output the list of supported formats For video that means pixel format For audio that means channel sample they are references to shared objects When the negotiation mechanism computes the intersection of the formats supported at each end of a all references to both lists are replaced with a reference to the intersection And when a single format is eventually chosen for a link amongst the remaining all references to the list are updated That means that if a filter requires that its input and output have the same format amongst a supported all it has to do is use a reference to the same list of formats query_formats can leave some formats unset and return AVERROR(EAGAIN) to cause the negotiation mechanism toagain later. That can be used by filters with complex requirements to use the format negotiated on one link to set the formats supported on another. Frame references ownership and permissions
opt.h
color
Definition: vf_paletteuse.c:599
ff_filter_frame
int ff_filter_frame(AVFilterLink *link, AVFrame *frame)
Send a frame of data to the next filter.
Definition: avfilter.c:1018
AV_OPT_TYPE_VIDEO_RATE
@ AV_OPT_TYPE_VIDEO_RATE
offset must point to AVRational
Definition: opt.h:237
inlink
The exact code depends on how similar the blocks are and how related they are to the and needs to apply these operations to the correct inlink or outlink if there are several Macros are available to factor that when no extra processing is inlink
Definition: filter_design.txt:212
AVFrame
This structure describes decoded (raw) audio or video data.
Definition: frame.h:303
AVFrame::pts
int64_t pts
Presentation timestamp in time_base units (time when frame should be shown to user).
Definition: frame.h:396
w
uint8_t w
Definition: llviddspenc.c:38
AVFILTER_DEFINE_CLASS
AVFILTER_DEFINE_CLASS(mandelbrot)
AVOption
AVOption.
Definition: opt.h:247
b
#define b
Definition: input.c:40
MBContext::point_cache
Point * point_cache
Definition: vsrc_mandelbrot.c:76
FLAGS
#define FLAGS
Definition: vsrc_mandelbrot.c:87
float.h
MBContext
Definition: vsrc_mandelbrot.c:60
FFMAX
#define FFMAX(a, b)
Definition: macros.h:47
MBContext::bailout
double bailout
Definition: vsrc_mandelbrot.c:71
PERIOD
@ PERIOD
Definition: vsrc_mandelbrot.c:50
AVFilter::name
const char * name
Filter name.
Definition: avfilter.h:153
MBContext::next_cache
Point * next_cache
Definition: vsrc_mandelbrot.c:77
video.h
MBContext::w
int w
Definition: vsrc_mandelbrot.c:62
AVFrame::data
uint8_t * data[AV_NUM_DATA_POINTERS]
pointer to the picture/channel planes.
Definition: frame.h:317
SQR
#define SQR(a)
Definition: vsrc_mandelbrot.c:39
formats.h
MBContext::start_scale
double start_scale
Definition: vsrc_mandelbrot.c:68
scale
static av_always_inline float scale(float x, float s)
Definition: vf_v360.c:1377
pts
static int64_t pts
Definition: transcode_aac.c:653
mandelbrot_outputs
static const AVFilterPad mandelbrot_outputs[]
Definition: vsrc_mandelbrot.c:399
config_props
static int config_props(AVFilterLink *inlink)
Definition: vsrc_mandelbrot.c:149
AVFilterPad
A filter pad used for either input or output.
Definition: internal.h:50
MBContext::start_x
double start_x
Definition: vsrc_mandelbrot.c:66
ipol
static int ipol(uint8_t *src, int x, int y)
Definition: rotozoom.c:65
lrint
#define lrint
Definition: tablegen.h:53
av_cold
#define av_cold
Definition: attributes.h:90
inputs
these buffered frames must be flushed immediately if a new input produces new the filter must not call request_frame to get more It must just process the frame or queue it The task of requesting more frames is left to the filter s request_frame method or the application If a filter has several inputs
Definition: filter_design.txt:243
Z_Z2_C
#define Z_Z2_C(outr, outi, inr, ini)
fill_from_cache
static void fill_from_cache(AVFilterContext *ctx, uint32_t *color, int *in_cidx, int *out_cidx, double py, double scale)
Definition: vsrc_mandelbrot.c:164
BLACK
@ BLACK
Definition: vsrc_mandelbrot.c:49
s
#define s(width, name)
Definition: cbs_vp9.c:257
MBContext::cache_allocated
int cache_allocated
Definition: vsrc_mandelbrot.c:74
floor
static __device__ float floor(float a)
Definition: cuda_runtime.h:173
AV_PIX_FMT_0BGR32
#define AV_PIX_FMT_0BGR32
Definition: pixfmt.h:369
AV_OPT_TYPE_DOUBLE
@ AV_OPT_TYPE_DOUBLE
Definition: opt.h:226
MBContext::cache_used
int cache_used
Definition: vsrc_mandelbrot.c:75
CONVTIME
@ CONVTIME
Definition: vsrc_mandelbrot.c:51
ctx
AVFormatContext * ctx
Definition: movenc.c:48
request_frame
static int request_frame(AVFilterLink *link)
Definition: vsrc_mandelbrot.c:385
link
Filter the word “frame” indicates either a video frame or a group of audio as stored in an AVFrame structure Format for each input and each output the list of supported formats For video that means pixel format For audio that means channel sample they are references to shared objects When the negotiation mechanism computes the intersection of the formats supported at each end of a link
Definition: filter_design.txt:23
FFABS
#define FFABS(a)
Absolute value, Note, INT_MIN / INT64_MIN result in undefined behavior as they are not representable ...
Definition: common.h:65
MBContext::frame_rate
AVRational frame_rate
Definition: vsrc_mandelbrot.c:63
AVClass
Describe the class of an AVClass context structure.
Definition: log.h:66
NULL
#define NULL
Definition: coverity.c:32
AVRational
Rational number (pair of numerator and denominator).
Definition: rational.h:58
ITERATION_COUNT
@ ITERATION_COUNT
Definition: vsrc_mandelbrot.c:42
AV_OPT_TYPE_IMAGE_SIZE
@ AV_OPT_TYPE_IMAGE_SIZE
offset must point to two consecutive integers
Definition: opt.h:234
MBContext::outer
int outer
Definition: vsrc_mandelbrot.c:72
parseutils.h
abs
#define abs(x)
Definition: cuda_runtime.h:35
MBContext::dither
uint32_t dither
Definition: vsrc_mandelbrot.c:79
sinf
#define sinf(x)
Definition: libm.h:419
MBContext::pts
uint64_t pts
Definition: vsrc_mandelbrot.c:64
c
Undefined Behavior In the C some operations are like signed integer dereferencing freed accessing outside allocated Undefined Behavior must not occur in a C it is not safe even if the output of undefined operations is unused The unsafety may seem nit picking but Optimizing compilers have in fact optimized code on the assumption that no undefined Behavior occurs Optimizing code based on wrong assumptions can and has in some cases lead to effects beyond the output of computations The signed integer overflow problem in speed critical code Code which is highly optimized and works with signed integers sometimes has the problem that often the output of the computation does not c
Definition: undefined.txt:32
Z_Z2_C_ZYKLUS
#define Z_Z2_C_ZYKLUS(outr, outi, inr, ini, Z)
Point
Definition: signature.h:54
Outer
Outer
Definition: vsrc_mandelbrot.c:41
dc
Tag MUST be and< 10hcoeff half pel interpolation filter coefficients, hcoeff[0] are the 2 middle coefficients[1] are the next outer ones and so on, resulting in a filter like:...eff[2], hcoeff[1], hcoeff[0], hcoeff[0], hcoeff[1], hcoeff[2] ... the sign of the coefficients is not explicitly stored but alternates after each coeff and coeff[0] is positive, so ...,+,-,+,-,+,+,-,+,-,+,... hcoeff[0] is not explicitly stored but found by subtracting the sum of all stored coefficients with signs from 32 hcoeff[0]=32 - hcoeff[1] - hcoeff[2] - ... a good choice for hcoeff and htaps is htaps=6 hcoeff={40,-10, 2} an alternative which requires more computations at both encoder and decoder side and may or may not be better is htaps=8 hcoeff={42,-14, 6,-2}ref_frames minimum of the number of available reference frames and max_ref_frames for example the first frame after a key frame always has ref_frames=1spatial_decomposition_type wavelet type 0 is a 9/7 symmetric compact integer wavelet 1 is a 5/3 symmetric compact integer wavelet others are reserved stored as delta from last, last is reset to 0 if always_reset||keyframeqlog quality(logarithmic quantizer scale) stored as delta from last, last is reset to 0 if always_reset||keyframemv_scale stored as delta from last, last is reset to 0 if always_reset||keyframe FIXME check that everything works fine if this changes between framesqbias dequantization bias stored as delta from last, last is reset to 0 if always_reset||keyframeblock_max_depth maximum depth of the block tree stored as delta from last, last is reset to 0 if always_reset||keyframequant_table quantization tableHighlevel bitstream structure:==============================--------------------------------------------|Header|--------------------------------------------|------------------------------------|||Block0||||split?||||yes no||||......... intra?||||:Block01 :yes no||||:Block02 :....... ..........||||:Block03 ::y DC ::ref index:||||:Block04 ::cb DC ::motion x :||||......... :cr DC ::motion y :||||....... ..........|||------------------------------------||------------------------------------|||Block1|||...|--------------------------------------------|------------ ------------ ------------|||Y subbands||Cb subbands||Cr subbands||||--- ---||--- ---||--- ---|||||LL0||HL0||||LL0||HL0||||LL0||HL0|||||--- ---||--- ---||--- ---||||--- ---||--- ---||--- ---|||||LH0||HH0||||LH0||HH0||||LH0||HH0|||||--- ---||--- ---||--- ---||||--- ---||--- ---||--- ---|||||HL1||LH1||||HL1||LH1||||HL1||LH1|||||--- ---||--- ---||--- ---||||--- ---||--- ---||--- ---|||||HH1||HL2||||HH1||HL2||||HH1||HL2|||||...||...||...|||------------ ------------ ------------|--------------------------------------------Decoding process:=================------------|||Subbands|------------||||------------|Intra DC||||LL0 subband prediction ------------|\ Dequantization ------------------- \||Reference frames|\ IDWT|------- -------|Motion \|||Frame 0||Frame 1||Compensation . OBMC v -------|------- -------|--------------. \------> Frame n output Frame Frame<----------------------------------/|...|------------------- Range Coder:============Binary Range Coder:------------------- The implemented range coder is an adapted version based upon "Range encoding: an algorithm for removing redundancy from a digitised message." by G. N. N. Martin. The symbols encoded by the Snow range coder are bits(0|1). The associated probabilities are not fix but change depending on the symbol mix seen so far. bit seen|new state ---------+----------------------------------------------- 0|256 - state_transition_table[256 - old_state];1|state_transition_table[old_state];state_transition_table={ 0, 0, 0, 0, 0, 0, 0, 0, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 37, 38, 39, 40, 41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51, 52, 53, 54, 55, 56, 56, 57, 58, 59, 60, 61, 62, 63, 64, 65, 66, 67, 68, 69, 70, 71, 72, 73, 74, 75, 75, 76, 77, 78, 79, 80, 81, 82, 83, 84, 85, 86, 87, 88, 89, 90, 91, 92, 93, 94, 94, 95, 96, 97, 98, 99, 100, 101, 102, 103, 104, 105, 106, 107, 108, 109, 110, 111, 112, 113, 114, 114, 115, 116, 117, 118, 119, 120, 121, 122, 123, 124, 125, 126, 127, 128, 129, 130, 131, 132, 133, 133, 134, 135, 136, 137, 138, 139, 140, 141, 142, 143, 144, 145, 146, 147, 148, 149, 150, 151, 152, 152, 153, 154, 155, 156, 157, 158, 159, 160, 161, 162, 163, 164, 165, 166, 167, 168, 169, 170, 171, 171, 172, 173, 174, 175, 176, 177, 178, 179, 180, 181, 182, 183, 184, 185, 186, 187, 188, 189, 190, 190, 191, 192, 194, 194, 195, 196, 197, 198, 199, 200, 201, 202, 202, 204, 205, 206, 207, 208, 209, 209, 210, 211, 212, 213, 215, 215, 216, 217, 218, 219, 220, 220, 222, 223, 224, 225, 226, 227, 227, 229, 229, 230, 231, 232, 234, 234, 235, 236, 237, 238, 239, 240, 241, 242, 243, 244, 245, 246, 247, 248, 248, 0, 0, 0, 0, 0, 0, 0};FIXME Range Coding of integers:------------------------- FIXME Neighboring Blocks:===================left and top are set to the respective blocks unless they are outside of the image in which case they are set to the Null block top-left is set to the top left block unless it is outside of the image in which case it is set to the left block if this block has no larger parent block or it is at the left side of its parent block and the top right block is not outside of the image then the top right block is used for top-right else the top-left block is used Null block y, cb, cr are 128 level, ref, mx and my are 0 Motion Vector Prediction:=========================1. the motion vectors of all the neighboring blocks are scaled to compensate for the difference of reference frames scaled_mv=(mv *(256 *(current_reference+1)/(mv.reference+1))+128)> the median of the scaled top and top right vectors is used as motion vector prediction the used motion vector is the sum of the predictor and(mvx_diff, mvy_diff) *mv_scale Intra DC Prediction block[y][x] dc[1]
Definition: snow.txt:400
NULL_IF_CONFIG_SMALL
#define NULL_IF_CONFIG_SMALL(x)
Return NULL if CONFIG_SMALL is true, otherwise the argument without modification.
Definition: internal.h:117
Point::val
uint32_t val
Definition: vsrc_mandelbrot.c:57
MBContext::morphamp
double morphamp
Definition: vsrc_mandelbrot.c:83
ff_vsrc_mandelbrot
const AVFilter ff_vsrc_mandelbrot
Definition: vsrc_mandelbrot.c:408
a
The reader does not expect b to be semantically here and if the code is changed by maybe adding a a division or other the signedness will almost certainly be mistaken To avoid this confusion a new type was SUINT is the C unsigned type but it holds a signed int to use the same example SUINT a
Definition: undefined.txt:41
MINCOL
@ MINCOL
Definition: vsrc_mandelbrot.c:52
uninit
static av_cold void uninit(AVFilterContext *ctx)
Definition: vsrc_mandelbrot.c:140
AV_LOG_INFO
#define AV_LOG_INFO
Standard information.
Definition: log.h:191
MBContext::maxiter
int maxiter
Definition: vsrc_mandelbrot.c:65
internal.h
FILTER_SINGLE_PIXFMT
#define FILTER_SINGLE_PIXFMT(pix_fmt_)
Definition: internal.h:181
MBContext::start_y
double start_y
Definition: vsrc_mandelbrot.c:67
lrintf
#define lrintf(x)
Definition: libm_mips.h:72
i
#define i(width, name, range_min, range_max)
Definition: cbs_h2645.c:271
av_malloc_array
#define av_malloc_array(a, b)
Definition: tableprint_vlc.h:32
FFMIN
#define FFMIN(a, b)
Definition: macros.h:49
av_inv_q
static av_always_inline AVRational av_inv_q(AVRational q)
Invert a rational.
Definition: rational.h:159
AVFilterPad::name
const char * name
Pad name.
Definition: internal.h:56
log2
#define log2(x)
Definition: libm.h:404
AVFilter
Filter definition.
Definition: avfilter.h:149
av_uninit
#define av_uninit(x)
Definition: attributes.h:154
FFSWAP
#define FFSWAP(type, a, b)
Definition: macros.h:52
MBContext::morphyf
double morphyf
Definition: vsrc_mandelbrot.c:82
AVFrame::sample_aspect_ratio
AVRational sample_aspect_ratio
Sample aspect ratio for the video frame, 0/1 if unknown/unspecified.
Definition: frame.h:391
MBContext::h
int h
Definition: vsrc_mandelbrot.c:62
mandelbrot_options
static const AVOption mandelbrot_options[]
Definition: vsrc_mandelbrot.c:89
OUTZ
@ OUTZ
Definition: vsrc_mandelbrot.c:45
AV_OPT_TYPE_INT
@ AV_OPT_TYPE_INT
Definition: opt.h:224
avfilter.h
MBContext::zyklus
double(* zyklus)[2]
Definition: vsrc_mandelbrot.c:78
Point::p
double p[2]
Definition: vsrc_mandelbrot.c:56
OFFSET
#define OFFSET(x)
Definition: vsrc_mandelbrot.c:86
AVFilterContext
An instance of a filter.
Definition: avfilter.h:386
AVMEDIA_TYPE_VIDEO
@ AVMEDIA_TYPE_VIDEO
Definition: avutil.h:201
cr
static double cr(void *priv, double x, double y)
Definition: vf_geq.c:216
FILTER_OUTPUTS
#define FILTER_OUTPUTS(array)
Definition: internal.h:192
av_freep
#define av_freep(p)
Definition: tableprint_vlc.h:35
d
d
Definition: ffmpeg_filter.c:156
imgutils.h
AVFrame::linesize
int linesize[AV_NUM_DATA_POINTERS]
For video, size in bytes of each picture line.
Definition: frame.h:334
av_log
#define av_log(a,...)
Definition: tableprint_vlc.h:28
MBContext::morphxf
double morphxf
Definition: vsrc_mandelbrot.c:81
h
h
Definition: vp9dsp_template.c:2038
MBContext::end_pts
double end_pts
Definition: vsrc_mandelbrot.c:70
av_image_check_size
int av_image_check_size(unsigned int w, unsigned int h, int log_offset, void *log_ctx)
Check if the given dimension of an image is valid, meaning that all bytes of the image can be address...
Definition: imgutils.c:318
int
int
Definition: ffmpeg_filter.c:156
AV_OPT_TYPE_CONST
@ AV_OPT_TYPE_CONST
Definition: opt.h:233
WHITE
@ WHITE
Definition: vsrc_mandelbrot.c:44
MBContext::inner
int inner
Definition: vsrc_mandelbrot.c:73