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vf_overlay.c
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1 /*
2  * Copyright (c) 2010 Stefano Sabatini
3  * Copyright (c) 2010 Baptiste Coudurier
4  * Copyright (c) 2007 Bobby Bingham
5  *
6  * This file is part of FFmpeg.
7  *
8  * FFmpeg is free software; you can redistribute it and/or
9  * modify it under the terms of the GNU Lesser General Public
10  * License as published by the Free Software Foundation; either
11  * version 2.1 of the License, or (at your option) any later version.
12  *
13  * FFmpeg is distributed in the hope that it will be useful,
14  * but WITHOUT ANY WARRANTY; without even the implied warranty of
15  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
16  * Lesser General Public License for more details.
17  *
18  * You should have received a copy of the GNU Lesser General Public
19  * License along with FFmpeg; if not, write to the Free Software
20  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
21  */
22 
23 /**
24  * @file
25  * overlay one video on top of another
26  */
27 
28 #include "avfilter.h"
29 #include "formats.h"
30 #include "libavutil/common.h"
31 #include "libavutil/eval.h"
32 #include "libavutil/avstring.h"
33 #include "libavutil/pixdesc.h"
34 #include "libavutil/imgutils.h"
35 #include "libavutil/mathematics.h"
36 #include "libavutil/opt.h"
37 #include "libavutil/timestamp.h"
38 #include "internal.h"
39 #include "dualinput.h"
40 #include "drawutils.h"
41 #include "video.h"
42 
43 static const char *const var_names[] = {
44  "main_w", "W", ///< width of the main video
45  "main_h", "H", ///< height of the main video
46  "overlay_w", "w", ///< width of the overlay video
47  "overlay_h", "h", ///< height of the overlay video
48  "hsub",
49  "vsub",
50  "x",
51  "y",
52  "n", ///< number of frame
53  "pos", ///< position in the file
54  "t", ///< timestamp expressed in seconds
55  NULL
56 };
57 
58 enum var_name {
71 };
72 
73 enum EOFAction {
77 };
78 
79 static const char *eof_action_str[] = {
80  "repeat", "endall", "pass"
81 };
82 
83 #define MAIN 0
84 #define OVERLAY 1
85 
86 #define R 0
87 #define G 1
88 #define B 2
89 #define A 3
90 
91 #define Y 0
92 #define U 1
93 #define V 2
94 
95 typedef struct OverlayContext {
96  const AVClass *class;
97  int x, y; ///< position of overlayed picture
98 
108 
110 
111  int main_pix_step[4]; ///< steps per pixel for each plane of the main output
112  int overlay_pix_step[4]; ///< steps per pixel for each plane of the overlay
113  int hsub, vsub; ///< chroma subsampling values
114 
116  char *x_expr, *y_expr;
117 
118  enum EOFAction eof_action; ///< action to take on EOF from source
119 
122 
123 static av_cold void uninit(AVFilterContext *ctx)
124 {
125  OverlayContext *s = ctx->priv;
126 
128  av_expr_free(s->x_pexpr); s->x_pexpr = NULL;
129  av_expr_free(s->y_pexpr); s->y_pexpr = NULL;
130 }
131 
132 static inline int normalize_xy(double d, int chroma_sub)
133 {
134  if (isnan(d))
135  return INT_MAX;
136  return (int)d & ~((1 << chroma_sub) - 1);
137 }
138 
139 static void eval_expr(AVFilterContext *ctx)
140 {
141  OverlayContext *s = ctx->priv;
142 
143  s->var_values[VAR_X] = av_expr_eval(s->x_pexpr, s->var_values, NULL);
144  s->var_values[VAR_Y] = av_expr_eval(s->y_pexpr, s->var_values, NULL);
145  s->var_values[VAR_X] = av_expr_eval(s->x_pexpr, s->var_values, NULL);
146  s->x = normalize_xy(s->var_values[VAR_X], s->hsub);
147  s->y = normalize_xy(s->var_values[VAR_Y], s->vsub);
148 }
149 
150 static int set_expr(AVExpr **pexpr, const char *expr, const char *option, void *log_ctx)
151 {
152  int ret;
153  AVExpr *old = NULL;
154 
155  if (*pexpr)
156  old = *pexpr;
157  ret = av_expr_parse(pexpr, expr, var_names,
158  NULL, NULL, NULL, NULL, 0, log_ctx);
159  if (ret < 0) {
160  av_log(log_ctx, AV_LOG_ERROR,
161  "Error when evaluating the expression '%s' for %s\n",
162  expr, option);
163  *pexpr = old;
164  return ret;
165  }
166 
167  av_expr_free(old);
168  return 0;
169 }
170 
171 static int process_command(AVFilterContext *ctx, const char *cmd, const char *args,
172  char *res, int res_len, int flags)
173 {
174  OverlayContext *s = ctx->priv;
175  int ret;
176 
177  if (!strcmp(cmd, "x"))
178  ret = set_expr(&s->x_pexpr, args, cmd, ctx);
179  else if (!strcmp(cmd, "y"))
180  ret = set_expr(&s->y_pexpr, args, cmd, ctx);
181  else
182  ret = AVERROR(ENOSYS);
183 
184  if (ret < 0)
185  return ret;
186 
187  if (s->eval_mode == EVAL_MODE_INIT) {
188  eval_expr(ctx);
189  av_log(ctx, AV_LOG_VERBOSE, "x:%f xi:%d y:%f yi:%d\n",
190  s->var_values[VAR_X], s->x,
191  s->var_values[VAR_Y], s->y);
192  }
193  return ret;
194 }
195 
197 {
198  OverlayContext *s = ctx->priv;
199 
200  /* overlay formats contains alpha, for avoiding conversion with alpha information loss */
201  static const enum AVPixelFormat main_pix_fmts_yuv420[] = {
203  };
204  static const enum AVPixelFormat overlay_pix_fmts_yuv420[] = {
206  };
207 
208  static const enum AVPixelFormat main_pix_fmts_yuv422[] = {
210  };
211  static const enum AVPixelFormat overlay_pix_fmts_yuv422[] = {
213  };
214 
215  static const enum AVPixelFormat main_pix_fmts_yuv444[] = {
217  };
218  static const enum AVPixelFormat overlay_pix_fmts_yuv444[] = {
220  };
221 
222  static const enum AVPixelFormat main_pix_fmts_rgb[] = {
227  };
228  static const enum AVPixelFormat overlay_pix_fmts_rgb[] = {
232  };
233 
234  AVFilterFormats *main_formats;
235  AVFilterFormats *overlay_formats;
236 
237  switch (s->format) {
238  case OVERLAY_FORMAT_YUV420:
239  main_formats = ff_make_format_list(main_pix_fmts_yuv420);
240  overlay_formats = ff_make_format_list(overlay_pix_fmts_yuv420);
241  break;
242  case OVERLAY_FORMAT_YUV422:
243  main_formats = ff_make_format_list(main_pix_fmts_yuv422);
244  overlay_formats = ff_make_format_list(overlay_pix_fmts_yuv422);
245  break;
246  case OVERLAY_FORMAT_YUV444:
247  main_formats = ff_make_format_list(main_pix_fmts_yuv444);
248  overlay_formats = ff_make_format_list(overlay_pix_fmts_yuv444);
249  break;
250  case OVERLAY_FORMAT_RGB:
251  main_formats = ff_make_format_list(main_pix_fmts_rgb);
252  overlay_formats = ff_make_format_list(overlay_pix_fmts_rgb);
253  break;
254  default:
255  av_assert0(0);
256  }
257 
258  ff_formats_ref(main_formats, &ctx->inputs [MAIN ]->out_formats);
259  ff_formats_ref(overlay_formats, &ctx->inputs [OVERLAY]->out_formats);
260  ff_formats_ref(main_formats, &ctx->outputs[MAIN ]->in_formats );
261 
262  return 0;
263 }
264 
265 static const enum AVPixelFormat alpha_pix_fmts[] = {
269 };
270 
271 static int config_input_main(AVFilterLink *inlink)
272 {
273  OverlayContext *s = inlink->dst->priv;
274  const AVPixFmtDescriptor *pix_desc = av_pix_fmt_desc_get(inlink->format);
275 
276  av_image_fill_max_pixsteps(s->main_pix_step, NULL, pix_desc);
277 
278  s->hsub = pix_desc->log2_chroma_w;
279  s->vsub = pix_desc->log2_chroma_h;
280 
281  s->main_is_packed_rgb =
282  ff_fill_rgba_map(s->main_rgba_map, inlink->format) >= 0;
284  return 0;
285 }
286 
288 {
289  AVFilterContext *ctx = inlink->dst;
290  OverlayContext *s = inlink->dst->priv;
291  int ret;
292  const AVPixFmtDescriptor *pix_desc = av_pix_fmt_desc_get(inlink->format);
293 
294  av_image_fill_max_pixsteps(s->overlay_pix_step, NULL, pix_desc);
295 
296  /* Finish the configuration by evaluating the expressions
297  now when both inputs are configured. */
298  s->var_values[VAR_MAIN_W ] = s->var_values[VAR_MW] = ctx->inputs[MAIN ]->w;
299  s->var_values[VAR_MAIN_H ] = s->var_values[VAR_MH] = ctx->inputs[MAIN ]->h;
302  s->var_values[VAR_HSUB] = 1<<pix_desc->log2_chroma_w;
303  s->var_values[VAR_VSUB] = 1<<pix_desc->log2_chroma_h;
304  s->var_values[VAR_X] = NAN;
305  s->var_values[VAR_Y] = NAN;
306  s->var_values[VAR_N] = 0;
307  s->var_values[VAR_T] = NAN;
308  s->var_values[VAR_POS] = NAN;
309 
310  if ((ret = set_expr(&s->x_pexpr, s->x_expr, "x", ctx)) < 0 ||
311  (ret = set_expr(&s->y_pexpr, s->y_expr, "y", ctx)) < 0)
312  return ret;
313 
315  ff_fill_rgba_map(s->overlay_rgba_map, inlink->format) >= 0;
317 
318  if (s->eval_mode == EVAL_MODE_INIT) {
319  eval_expr(ctx);
320  av_log(ctx, AV_LOG_VERBOSE, "x:%f xi:%d y:%f yi:%d\n",
321  s->var_values[VAR_X], s->x,
322  s->var_values[VAR_Y], s->y);
323  }
324 
325  av_log(ctx, AV_LOG_VERBOSE,
326  "main w:%d h:%d fmt:%s overlay w:%d h:%d fmt:%s eof_action:%s\n",
327  ctx->inputs[MAIN]->w, ctx->inputs[MAIN]->h,
329  ctx->inputs[OVERLAY]->w, ctx->inputs[OVERLAY]->h,
332  return 0;
333 }
334 
335 static int config_output(AVFilterLink *outlink)
336 {
337  AVFilterContext *ctx = outlink->src;
338  OverlayContext *s = ctx->priv;
339  int ret;
340 
341  if ((ret = ff_dualinput_init(ctx, &s->dinput)) < 0)
342  return ret;
343 
344  outlink->w = ctx->inputs[MAIN]->w;
345  outlink->h = ctx->inputs[MAIN]->h;
346  outlink->time_base = ctx->inputs[MAIN]->time_base;
347 
348  return 0;
349 }
350 
351 // divide by 255 and round to nearest
352 // apply a fast variant: (X+127)/255 = ((X+127)*257+257)>>16 = ((X+128)*257)>>16
353 #define FAST_DIV255(x) ((((x) + 128) * 257) >> 16)
354 
355 // calculate the unpremultiplied alpha, applying the general equation:
356 // alpha = alpha_overlay / ( (alpha_main + alpha_overlay) - (alpha_main * alpha_overlay) )
357 // (((x) << 16) - ((x) << 9) + (x)) is a faster version of: 255 * 255 * x
358 // ((((x) + (y)) << 8) - ((x) + (y)) - (y) * (x)) is a faster version of: 255 * (x + y)
359 #define UNPREMULTIPLY_ALPHA(x, y) ((((x) << 16) - ((x) << 9) + (x)) / ((((x) + (y)) << 8) - ((x) + (y)) - (y) * (x)))
360 
361 /**
362  * Blend image in src to destination buffer dst at position (x, y).
363  */
364 static void blend_image(AVFilterContext *ctx,
365  AVFrame *dst, const AVFrame *src,
366  int x, int y)
367 {
368  OverlayContext *s = ctx->priv;
369  int i, imax, j, jmax, k, kmax;
370  const int src_w = src->width;
371  const int src_h = src->height;
372  const int dst_w = dst->width;
373  const int dst_h = dst->height;
374 
375  if (x >= dst_w || x+src_w < 0 ||
376  y >= dst_h || y+src_h < 0)
377  return; /* no intersection */
378 
379  if (s->main_is_packed_rgb) {
380  uint8_t alpha; ///< the amount of overlay to blend on to main
381  const int dr = s->main_rgba_map[R];
382  const int dg = s->main_rgba_map[G];
383  const int db = s->main_rgba_map[B];
384  const int da = s->main_rgba_map[A];
385  const int dstep = s->main_pix_step[0];
386  const int sr = s->overlay_rgba_map[R];
387  const int sg = s->overlay_rgba_map[G];
388  const int sb = s->overlay_rgba_map[B];
389  const int sa = s->overlay_rgba_map[A];
390  const int sstep = s->overlay_pix_step[0];
391  const int main_has_alpha = s->main_has_alpha;
392  uint8_t *s, *sp, *d, *dp;
393 
394  i = FFMAX(-y, 0);
395  sp = src->data[0] + i * src->linesize[0];
396  dp = dst->data[0] + (y+i) * dst->linesize[0];
397 
398  for (imax = FFMIN(-y + dst_h, src_h); i < imax; i++) {
399  j = FFMAX(-x, 0);
400  s = sp + j * sstep;
401  d = dp + (x+j) * dstep;
402 
403  for (jmax = FFMIN(-x + dst_w, src_w); j < jmax; j++) {
404  alpha = s[sa];
405 
406  // if the main channel has an alpha channel, alpha has to be calculated
407  // to create an un-premultiplied (straight) alpha value
408  if (main_has_alpha && alpha != 0 && alpha != 255) {
409  uint8_t alpha_d = d[da];
410  alpha = UNPREMULTIPLY_ALPHA(alpha, alpha_d);
411  }
412 
413  switch (alpha) {
414  case 0:
415  break;
416  case 255:
417  d[dr] = s[sr];
418  d[dg] = s[sg];
419  d[db] = s[sb];
420  break;
421  default:
422  // main_value = main_value * (1 - alpha) + overlay_value * alpha
423  // since alpha is in the range 0-255, the result must divided by 255
424  d[dr] = FAST_DIV255(d[dr] * (255 - alpha) + s[sr] * alpha);
425  d[dg] = FAST_DIV255(d[dg] * (255 - alpha) + s[sg] * alpha);
426  d[db] = FAST_DIV255(d[db] * (255 - alpha) + s[sb] * alpha);
427  }
428  if (main_has_alpha) {
429  switch (alpha) {
430  case 0:
431  break;
432  case 255:
433  d[da] = s[sa];
434  break;
435  default:
436  // apply alpha compositing: main_alpha += (1-main_alpha) * overlay_alpha
437  d[da] += FAST_DIV255((255 - d[da]) * s[sa]);
438  }
439  }
440  d += dstep;
441  s += sstep;
442  }
443  dp += dst->linesize[0];
444  sp += src->linesize[0];
445  }
446  } else {
447  const int main_has_alpha = s->main_has_alpha;
448  if (main_has_alpha) {
449  uint8_t alpha; ///< the amount of overlay to blend on to main
450  uint8_t *s, *sa, *d, *da;
451 
452  i = FFMAX(-y, 0);
453  sa = src->data[3] + i * src->linesize[3];
454  da = dst->data[3] + (y+i) * dst->linesize[3];
455 
456  for (imax = FFMIN(-y + dst_h, src_h); i < imax; i++) {
457  j = FFMAX(-x, 0);
458  s = sa + j;
459  d = da + x+j;
460 
461  for (jmax = FFMIN(-x + dst_w, src_w); j < jmax; j++) {
462  alpha = *s;
463  if (alpha != 0 && alpha != 255) {
464  uint8_t alpha_d = *d;
465  alpha = UNPREMULTIPLY_ALPHA(alpha, alpha_d);
466  }
467  switch (alpha) {
468  case 0:
469  break;
470  case 255:
471  *d = *s;
472  break;
473  default:
474  // apply alpha compositing: main_alpha += (1-main_alpha) * overlay_alpha
475  *d += FAST_DIV255((255 - *d) * *s);
476  }
477  d += 1;
478  s += 1;
479  }
480  da += dst->linesize[3];
481  sa += src->linesize[3];
482  }
483  }
484  for (i = 0; i < 3; i++) {
485  int hsub = i ? s->hsub : 0;
486  int vsub = i ? s->vsub : 0;
487  int src_wp = FF_CEIL_RSHIFT(src_w, hsub);
488  int src_hp = FF_CEIL_RSHIFT(src_h, vsub);
489  int dst_wp = FF_CEIL_RSHIFT(dst_w, hsub);
490  int dst_hp = FF_CEIL_RSHIFT(dst_h, vsub);
491  int yp = y>>vsub;
492  int xp = x>>hsub;
493  uint8_t *s, *sp, *d, *dp, *a, *ap;
494 
495  j = FFMAX(-yp, 0);
496  sp = src->data[i] + j * src->linesize[i];
497  dp = dst->data[i] + (yp+j) * dst->linesize[i];
498  ap = src->data[3] + (j<<vsub) * src->linesize[3];
499 
500  for (jmax = FFMIN(-yp + dst_hp, src_hp); j < jmax; j++) {
501  k = FFMAX(-xp, 0);
502  d = dp + xp+k;
503  s = sp + k;
504  a = ap + (k<<hsub);
505 
506  for (kmax = FFMIN(-xp + dst_wp, src_wp); k < kmax; k++) {
507  int alpha_v, alpha_h, alpha;
508 
509  // average alpha for color components, improve quality
510  if (hsub && vsub && j+1 < src_hp && k+1 < src_wp) {
511  alpha = (a[0] + a[src->linesize[3]] +
512  a[1] + a[src->linesize[3]+1]) >> 2;
513  } else if (hsub || vsub) {
514  alpha_h = hsub && k+1 < src_wp ?
515  (a[0] + a[1]) >> 1 : a[0];
516  alpha_v = vsub && j+1 < src_hp ?
517  (a[0] + a[src->linesize[3]]) >> 1 : a[0];
518  alpha = (alpha_v + alpha_h) >> 1;
519  } else
520  alpha = a[0];
521  // if the main channel has an alpha channel, alpha has to be calculated
522  // to create an un-premultiplied (straight) alpha value
523  if (main_has_alpha && alpha != 0 && alpha != 255) {
524  // average alpha for color components, improve quality
525  uint8_t alpha_d;
526  if (hsub && vsub && j+1 < src_hp && k+1 < src_wp) {
527  alpha_d = (d[0] + d[src->linesize[3]] +
528  d[1] + d[src->linesize[3]+1]) >> 2;
529  } else if (hsub || vsub) {
530  alpha_h = hsub && k+1 < src_wp ?
531  (d[0] + d[1]) >> 1 : d[0];
532  alpha_v = vsub && j+1 < src_hp ?
533  (d[0] + d[src->linesize[3]]) >> 1 : d[0];
534  alpha_d = (alpha_v + alpha_h) >> 1;
535  } else
536  alpha_d = d[0];
537  alpha = UNPREMULTIPLY_ALPHA(alpha, alpha_d);
538  }
539  *d = FAST_DIV255(*d * (255 - alpha) + *s * alpha);
540  s++;
541  d++;
542  a += 1 << hsub;
543  }
544  dp += dst->linesize[i];
545  sp += src->linesize[i];
546  ap += (1 << vsub) * src->linesize[3];
547  }
548  }
549  }
550 }
551 
552 static AVFrame *do_blend(AVFilterContext *ctx, AVFrame *mainpic,
553  const AVFrame *second)
554 {
555  OverlayContext *s = ctx->priv;
556  AVFilterLink *inlink = ctx->inputs[0];
557 
558  if (s->eval_mode == EVAL_MODE_FRAME) {
559  int64_t pos = av_frame_get_pkt_pos(mainpic);
560 
561  s->var_values[VAR_N] = inlink->frame_count;
562  s->var_values[VAR_T] = mainpic->pts == AV_NOPTS_VALUE ?
563  NAN : mainpic->pts * av_q2d(inlink->time_base);
564  s->var_values[VAR_POS] = pos == -1 ? NAN : pos;
565 
566  eval_expr(ctx);
567  av_log(ctx, AV_LOG_DEBUG, "n:%f t:%f pos:%f x:%f xi:%d y:%f yi:%d\n",
569  s->var_values[VAR_X], s->x,
570  s->var_values[VAR_Y], s->y);
571  }
572 
573  blend_image(ctx, mainpic, second, s->x, s->y);
574  return mainpic;
575 }
576 
577 static int filter_frame(AVFilterLink *inlink, AVFrame *inpicref)
578 {
579  OverlayContext *s = inlink->dst->priv;
580  av_log(inlink->dst, AV_LOG_DEBUG, "Incoming frame (time:%s) from link #%d\n", av_ts2timestr(inpicref->pts, &inlink->time_base), FF_INLINK_IDX(inlink));
581  return ff_dualinput_filter_frame(&s->dinput, inlink, inpicref);
582 }
583 
584 static int request_frame(AVFilterLink *outlink)
585 {
586  OverlayContext *s = outlink->src->priv;
587  return ff_dualinput_request_frame(&s->dinput, outlink);
588 }
589 
590 static av_cold int init(AVFilterContext *ctx)
591 {
592  OverlayContext *s = ctx->priv;
593 
594  if (s->allow_packed_rgb) {
595  av_log(ctx, AV_LOG_WARNING,
596  "The rgb option is deprecated and is overriding the format option, use format instead\n");
597  s->format = OVERLAY_FORMAT_RGB;
598  }
599  if (!s->dinput.repeatlast || s->eof_action == EOF_ACTION_PASS) {
600  s->dinput.repeatlast = 0;
602  }
603  if (s->dinput.shortest || s->eof_action == EOF_ACTION_ENDALL) {
604  s->dinput.shortest = 1;
606  }
607 
608  s->dinput.process = do_blend;
609  return 0;
610 }
611 
612 #define OFFSET(x) offsetof(OverlayContext, x)
613 #define FLAGS AV_OPT_FLAG_VIDEO_PARAM|AV_OPT_FLAG_FILTERING_PARAM
614 
615 static const AVOption overlay_options[] = {
616  { "x", "set the x expression", OFFSET(x_expr), AV_OPT_TYPE_STRING, {.str = "0"}, CHAR_MIN, CHAR_MAX, FLAGS },
617  { "y", "set the y expression", OFFSET(y_expr), AV_OPT_TYPE_STRING, {.str = "0"}, CHAR_MIN, CHAR_MAX, FLAGS },
618  { "eof_action", "Action to take when encountering EOF from secondary input ",
619  OFFSET(eof_action), AV_OPT_TYPE_INT, { .i64 = EOF_ACTION_REPEAT },
620  EOF_ACTION_REPEAT, EOF_ACTION_PASS, .flags = FLAGS, "eof_action" },
621  { "repeat", "Repeat the previous frame.", 0, AV_OPT_TYPE_CONST, { .i64 = EOF_ACTION_REPEAT }, .flags = FLAGS, "eof_action" },
622  { "endall", "End both streams.", 0, AV_OPT_TYPE_CONST, { .i64 = EOF_ACTION_ENDALL }, .flags = FLAGS, "eof_action" },
623  { "pass", "Pass through the main input.", 0, AV_OPT_TYPE_CONST, { .i64 = EOF_ACTION_PASS }, .flags = FLAGS, "eof_action" },
624  { "eval", "specify when to evaluate expressions", OFFSET(eval_mode), AV_OPT_TYPE_INT, {.i64 = EVAL_MODE_FRAME}, 0, EVAL_MODE_NB-1, FLAGS, "eval" },
625  { "init", "eval expressions once during initialization", 0, AV_OPT_TYPE_CONST, {.i64=EVAL_MODE_INIT}, .flags = FLAGS, .unit = "eval" },
626  { "frame", "eval expressions per-frame", 0, AV_OPT_TYPE_CONST, {.i64=EVAL_MODE_FRAME}, .flags = FLAGS, .unit = "eval" },
627  { "rgb", "force packed RGB in input and output (deprecated)", OFFSET(allow_packed_rgb), AV_OPT_TYPE_INT, {.i64=0}, 0, 1, FLAGS },
628  { "shortest", "force termination when the shortest input terminates", OFFSET(dinput.shortest), AV_OPT_TYPE_INT, { .i64 = 0 }, 0, 1, FLAGS },
629  { "format", "set output format", OFFSET(format), AV_OPT_TYPE_INT, {.i64=OVERLAY_FORMAT_YUV420}, 0, OVERLAY_FORMAT_NB-1, FLAGS, "format" },
630  { "yuv420", "", 0, AV_OPT_TYPE_CONST, {.i64=OVERLAY_FORMAT_YUV420}, .flags = FLAGS, .unit = "format" },
631  { "yuv422", "", 0, AV_OPT_TYPE_CONST, {.i64=OVERLAY_FORMAT_YUV422}, .flags = FLAGS, .unit = "format" },
632  { "yuv444", "", 0, AV_OPT_TYPE_CONST, {.i64=OVERLAY_FORMAT_YUV444}, .flags = FLAGS, .unit = "format" },
633  { "rgb", "", 0, AV_OPT_TYPE_CONST, {.i64=OVERLAY_FORMAT_RGB}, .flags = FLAGS, .unit = "format" },
634  { "repeatlast", "repeat overlay of the last overlay frame", OFFSET(dinput.repeatlast), AV_OPT_TYPE_INT, {.i64=1}, 0, 1, FLAGS },
635  { NULL }
636 };
637 
638 AVFILTER_DEFINE_CLASS(overlay);
639 
641  {
642  .name = "main",
643  .type = AVMEDIA_TYPE_VIDEO,
644  .config_props = config_input_main,
645  .filter_frame = filter_frame,
646  .needs_writable = 1,
647  },
648  {
649  .name = "overlay",
650  .type = AVMEDIA_TYPE_VIDEO,
651  .config_props = config_input_overlay,
652  .filter_frame = filter_frame,
653  },
654  { NULL }
655 };
656 
658  {
659  .name = "default",
660  .type = AVMEDIA_TYPE_VIDEO,
661  .config_props = config_output,
662  .request_frame = request_frame,
663  },
664  { NULL }
665 };
666 
668  .name = "overlay",
669  .description = NULL_IF_CONFIG_SMALL("Overlay a video source on top of the input."),
670  .init = init,
671  .uninit = uninit,
672  .priv_size = sizeof(OverlayContext),
673  .priv_class = &overlay_class,
676  .inputs = avfilter_vf_overlay_inputs,
677  .outputs = avfilter_vf_overlay_outputs,
679 };