FFmpeg
vf_scale.c
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1 /*
2  * Copyright (c) 2007 Bobby Bingham
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 
21 /**
22  * @file
23  * scale video filter
24  */
25 
26 #include <stdio.h>
27 #include <string.h>
28 
29 #include "avfilter.h"
30 #include "formats.h"
31 #include "internal.h"
32 #include "scale_eval.h"
33 #include "video.h"
34 #include "libavutil/avstring.h"
35 #include "libavutil/eval.h"
36 #include "libavutil/internal.h"
37 #include "libavutil/mathematics.h"
38 #include "libavutil/opt.h"
39 #include "libavutil/parseutils.h"
40 #include "libavutil/pixdesc.h"
41 #include "libavutil/imgutils.h"
42 #include "libswscale/swscale.h"
43 
44 static const char *const var_names[] = {
45  "in_w", "iw",
46  "in_h", "ih",
47  "out_w", "ow",
48  "out_h", "oh",
49  "a",
50  "sar",
51  "dar",
52  "hsub",
53  "vsub",
54  "ohsub",
55  "ovsub",
56  "n",
57  "t",
58  "pos",
59  "main_w",
60  "main_h",
61  "main_a",
62  "main_sar",
63  "main_dar", "mdar",
64  "main_hsub",
65  "main_vsub",
66  "main_n",
67  "main_t",
68  "main_pos",
69  NULL
70 };
71 
72 enum var_name {
98 };
99 
100 enum EvalMode {
104 };
105 
106 typedef struct ScaleContext {
107  const AVClass *class;
108  struct SwsContext *sws; ///< software scaler context
109  struct SwsContext *isws[2]; ///< software scaler context for interlaced material
111 
112  /**
113  * New dimensions. Special values are:
114  * 0 = original width/height
115  * -1 = keep original aspect
116  * -N = try to keep aspect but make sure it is divisible by N
117  */
118  int w, h;
119  char *size_str;
120  unsigned int flags; ///sws flags
121  double param[2]; // sws params
122 
123  int hsub, vsub; ///< chroma subsampling
124  int slice_y; ///< top of current output slice
125  int input_is_pal; ///< set to 1 if the input format is paletted
126  int output_is_pal; ///< set to 1 if the output format is paletted
128 
129  char *w_expr; ///< width expression string
130  char *h_expr; ///< height expression string
134 
135  char *flags_str;
136 
139 
140  int in_range;
142 
147 
150 
151  int eval_mode; ///< expression evaluation mode
152 
153 } ScaleContext;
154 
156 
157 static int config_props(AVFilterLink *outlink);
158 
160 {
161  ScaleContext *scale = ctx->priv;
162  unsigned vars_w[VARS_NB] = { 0 }, vars_h[VARS_NB] = { 0 };
163 
164  if (!scale->w_pexpr && !scale->h_pexpr)
165  return AVERROR(EINVAL);
166 
167  if (scale->w_pexpr)
168  av_expr_count_vars(scale->w_pexpr, vars_w, VARS_NB);
169  if (scale->h_pexpr)
170  av_expr_count_vars(scale->h_pexpr, vars_h, VARS_NB);
171 
172  if (vars_w[VAR_OUT_W] || vars_w[VAR_OW]) {
173  av_log(ctx, AV_LOG_ERROR, "Width expression cannot be self-referencing: '%s'.\n", scale->w_expr);
174  return AVERROR(EINVAL);
175  }
176 
177  if (vars_h[VAR_OUT_H] || vars_h[VAR_OH]) {
178  av_log(ctx, AV_LOG_ERROR, "Height expression cannot be self-referencing: '%s'.\n", scale->h_expr);
179  return AVERROR(EINVAL);
180  }
181 
182  if ((vars_w[VAR_OUT_H] || vars_w[VAR_OH]) &&
183  (vars_h[VAR_OUT_W] || vars_h[VAR_OW])) {
184  av_log(ctx, AV_LOG_WARNING, "Circular references detected for width '%s' and height '%s' - possibly invalid.\n", scale->w_expr, scale->h_expr);
185  }
186 
187  if (ctx->filter != &ff_vf_scale2ref &&
188  (vars_w[VAR_S2R_MAIN_W] || vars_h[VAR_S2R_MAIN_W] ||
189  vars_w[VAR_S2R_MAIN_H] || vars_h[VAR_S2R_MAIN_H] ||
190  vars_w[VAR_S2R_MAIN_A] || vars_h[VAR_S2R_MAIN_A] ||
191  vars_w[VAR_S2R_MAIN_SAR] || vars_h[VAR_S2R_MAIN_SAR] ||
192  vars_w[VAR_S2R_MAIN_DAR] || vars_h[VAR_S2R_MAIN_DAR] ||
193  vars_w[VAR_S2R_MDAR] || vars_h[VAR_S2R_MDAR] ||
194  vars_w[VAR_S2R_MAIN_HSUB] || vars_h[VAR_S2R_MAIN_HSUB] ||
195  vars_w[VAR_S2R_MAIN_VSUB] || vars_h[VAR_S2R_MAIN_VSUB] ||
196  vars_w[VAR_S2R_MAIN_N] || vars_h[VAR_S2R_MAIN_N] ||
197  vars_w[VAR_S2R_MAIN_T] || vars_h[VAR_S2R_MAIN_T] ||
198  vars_w[VAR_S2R_MAIN_POS] || vars_h[VAR_S2R_MAIN_POS]) ) {
199  av_log(ctx, AV_LOG_ERROR, "Expressions with scale2ref variables are not valid in scale filter.\n");
200  return AVERROR(EINVAL);
201  }
202 
203  if (scale->eval_mode == EVAL_MODE_INIT &&
204  (vars_w[VAR_N] || vars_h[VAR_N] ||
205  vars_w[VAR_T] || vars_h[VAR_T] ||
206  vars_w[VAR_POS] || vars_h[VAR_POS] ||
207  vars_w[VAR_S2R_MAIN_N] || vars_h[VAR_S2R_MAIN_N] ||
208  vars_w[VAR_S2R_MAIN_T] || vars_h[VAR_S2R_MAIN_T] ||
209  vars_w[VAR_S2R_MAIN_POS] || vars_h[VAR_S2R_MAIN_POS]) ) {
210  av_log(ctx, AV_LOG_ERROR, "Expressions with frame variables 'n', 't', 'pos' are not valid in init eval_mode.\n");
211  return AVERROR(EINVAL);
212  }
213 
214  return 0;
215 }
216 
217 static int scale_parse_expr(AVFilterContext *ctx, char *str_expr, AVExpr **pexpr_ptr, const char *var, const char *args)
218 {
219  ScaleContext *scale = ctx->priv;
220  int ret, is_inited = 0;
221  char *old_str_expr = NULL;
222  AVExpr *old_pexpr = NULL;
223 
224  if (str_expr) {
225  old_str_expr = av_strdup(str_expr);
226  if (!old_str_expr)
227  return AVERROR(ENOMEM);
228  av_opt_set(scale, var, args, 0);
229  }
230 
231  if (*pexpr_ptr) {
232  old_pexpr = *pexpr_ptr;
233  *pexpr_ptr = NULL;
234  is_inited = 1;
235  }
236 
237  ret = av_expr_parse(pexpr_ptr, args, var_names,
238  NULL, NULL, NULL, NULL, 0, ctx);
239  if (ret < 0) {
240  av_log(ctx, AV_LOG_ERROR, "Cannot parse expression for %s: '%s'\n", var, args);
241  goto revert;
242  }
243 
244  ret = check_exprs(ctx);
245  if (ret < 0)
246  goto revert;
247 
248  if (is_inited && (ret = config_props(ctx->outputs[0])) < 0)
249  goto revert;
250 
251  av_expr_free(old_pexpr);
252  old_pexpr = NULL;
253  av_freep(&old_str_expr);
254 
255  return 0;
256 
257 revert:
258  av_expr_free(*pexpr_ptr);
259  *pexpr_ptr = NULL;
260  if (old_str_expr) {
261  av_opt_set(scale, var, old_str_expr, 0);
262  av_free(old_str_expr);
263  }
264  if (old_pexpr)
265  *pexpr_ptr = old_pexpr;
266 
267  return ret;
268 }
269 
271 {
272  ScaleContext *scale = ctx->priv;
273  int ret;
274 
275  if (scale->size_str && (scale->w_expr || scale->h_expr)) {
277  "Size and width/height expressions cannot be set at the same time.\n");
278  return AVERROR(EINVAL);
279  }
280 
281  if (scale->w_expr && !scale->h_expr)
282  FFSWAP(char *, scale->w_expr, scale->size_str);
283 
284  if (scale->size_str) {
285  char buf[32];
286  if ((ret = av_parse_video_size(&scale->w, &scale->h, scale->size_str)) < 0) {
288  "Invalid size '%s'\n", scale->size_str);
289  return ret;
290  }
291  snprintf(buf, sizeof(buf)-1, "%d", scale->w);
292  av_opt_set(scale, "w", buf, 0);
293  snprintf(buf, sizeof(buf)-1, "%d", scale->h);
294  av_opt_set(scale, "h", buf, 0);
295  }
296  if (!scale->w_expr)
297  av_opt_set(scale, "w", "iw", 0);
298  if (!scale->h_expr)
299  av_opt_set(scale, "h", "ih", 0);
300 
301  ret = scale_parse_expr(ctx, NULL, &scale->w_pexpr, "width", scale->w_expr);
302  if (ret < 0)
303  return ret;
304 
305  ret = scale_parse_expr(ctx, NULL, &scale->h_pexpr, "height", scale->h_expr);
306  if (ret < 0)
307  return ret;
308 
309  av_log(ctx, AV_LOG_VERBOSE, "w:%s h:%s flags:'%s' interl:%d\n",
310  scale->w_expr, scale->h_expr, (char *)av_x_if_null(scale->flags_str, ""), scale->interlaced);
311 
312  scale->flags = 0;
313 
314  if (scale->flags_str && *scale->flags_str) {
315  const AVClass *class = sws_get_class();
316  const AVOption *o = av_opt_find(&class, "sws_flags", NULL, 0,
318  int ret = av_opt_eval_flags(&class, o, scale->flags_str, &scale->flags);
319  if (ret < 0)
320  return ret;
321  }
322  scale->opts = *opts;
323  *opts = NULL;
324 
325  return 0;
326 }
327 
329 {
330  ScaleContext *scale = ctx->priv;
331  av_expr_free(scale->w_pexpr);
332  av_expr_free(scale->h_pexpr);
333  scale->w_pexpr = scale->h_pexpr = NULL;
334  sws_freeContext(scale->sws);
335  sws_freeContext(scale->isws[0]);
336  sws_freeContext(scale->isws[1]);
337  scale->sws = NULL;
338  av_dict_free(&scale->opts);
339 }
340 
342 {
344  const AVPixFmtDescriptor *desc;
345  enum AVPixelFormat pix_fmt;
346  int ret;
347 
348  desc = NULL;
349  formats = NULL;
350  while ((desc = av_pix_fmt_desc_next(desc))) {
354  && (ret = ff_add_format(&formats, pix_fmt)) < 0) {
355  return ret;
356  }
357  }
358  if ((ret = ff_formats_ref(formats, &ctx->inputs[0]->outcfg.formats)) < 0)
359  return ret;
360 
361  desc = NULL;
362  formats = NULL;
363  while ((desc = av_pix_fmt_desc_next(desc))) {
367  && (ret = ff_add_format(&formats, pix_fmt)) < 0) {
368  return ret;
369  }
370  }
371  if ((ret = ff_formats_ref(formats, &ctx->outputs[0]->incfg.formats)) < 0)
372  return ret;
373 
374  return 0;
375 }
376 
377 static const int *parse_yuv_type(const char *s, enum AVColorSpace colorspace)
378 {
379  if (!s)
380  s = "bt601";
381 
382  if (s && strstr(s, "bt709")) {
383  colorspace = AVCOL_SPC_BT709;
384  } else if (s && strstr(s, "fcc")) {
385  colorspace = AVCOL_SPC_FCC;
386  } else if (s && strstr(s, "smpte240m")) {
387  colorspace = AVCOL_SPC_SMPTE240M;
388  } else if (s && (strstr(s, "bt601") || strstr(s, "bt470") || strstr(s, "smpte170m"))) {
389  colorspace = AVCOL_SPC_BT470BG;
390  } else if (s && strstr(s, "bt2020")) {
391  colorspace = AVCOL_SPC_BT2020_NCL;
392  }
393 
394  if (colorspace < 1 || colorspace > 10 || colorspace == 8) {
395  colorspace = AVCOL_SPC_BT470BG;
396  }
397 
398  return sws_getCoefficients(colorspace);
399 }
400 
402 {
403  ScaleContext *scale = ctx->priv;
404  const char scale2ref = ctx->filter == &ff_vf_scale2ref;
405  const AVFilterLink *inlink = scale2ref ? ctx->inputs[1] : ctx->inputs[0];
406  const AVFilterLink *outlink = ctx->outputs[0];
408  const AVPixFmtDescriptor *out_desc = av_pix_fmt_desc_get(outlink->format);
409  char *expr;
410  int eval_w, eval_h;
411  int ret;
412  double res;
413  const AVPixFmtDescriptor *main_desc;
414  const AVFilterLink *main_link;
415 
416  if (scale2ref) {
417  main_link = ctx->inputs[0];
418  main_desc = av_pix_fmt_desc_get(main_link->format);
419  }
420 
421  scale->var_values[VAR_IN_W] = scale->var_values[VAR_IW] = inlink->w;
422  scale->var_values[VAR_IN_H] = scale->var_values[VAR_IH] = inlink->h;
423  scale->var_values[VAR_OUT_W] = scale->var_values[VAR_OW] = NAN;
424  scale->var_values[VAR_OUT_H] = scale->var_values[VAR_OH] = NAN;
425  scale->var_values[VAR_A] = (double) inlink->w / inlink->h;
426  scale->var_values[VAR_SAR] = inlink->sample_aspect_ratio.num ?
427  (double) inlink->sample_aspect_ratio.num / inlink->sample_aspect_ratio.den : 1;
428  scale->var_values[VAR_DAR] = scale->var_values[VAR_A] * scale->var_values[VAR_SAR];
429  scale->var_values[VAR_HSUB] = 1 << desc->log2_chroma_w;
430  scale->var_values[VAR_VSUB] = 1 << desc->log2_chroma_h;
431  scale->var_values[VAR_OHSUB] = 1 << out_desc->log2_chroma_w;
432  scale->var_values[VAR_OVSUB] = 1 << out_desc->log2_chroma_h;
433 
434  if (scale2ref) {
435  scale->var_values[VAR_S2R_MAIN_W] = main_link->w;
436  scale->var_values[VAR_S2R_MAIN_H] = main_link->h;
437  scale->var_values[VAR_S2R_MAIN_A] = (double) main_link->w / main_link->h;
438  scale->var_values[VAR_S2R_MAIN_SAR] = main_link->sample_aspect_ratio.num ?
439  (double) main_link->sample_aspect_ratio.num / main_link->sample_aspect_ratio.den : 1;
440  scale->var_values[VAR_S2R_MAIN_DAR] = scale->var_values[VAR_S2R_MDAR] =
441  scale->var_values[VAR_S2R_MAIN_A] * scale->var_values[VAR_S2R_MAIN_SAR];
442  scale->var_values[VAR_S2R_MAIN_HSUB] = 1 << main_desc->log2_chroma_w;
443  scale->var_values[VAR_S2R_MAIN_VSUB] = 1 << main_desc->log2_chroma_h;
444  }
445 
446  res = av_expr_eval(scale->w_pexpr, scale->var_values, NULL);
447  eval_w = scale->var_values[VAR_OUT_W] = scale->var_values[VAR_OW] = (int) res == 0 ? inlink->w : (int) res;
448 
449  res = av_expr_eval(scale->h_pexpr, scale->var_values, NULL);
450  if (isnan(res)) {
451  expr = scale->h_expr;
452  ret = AVERROR(EINVAL);
453  goto fail;
454  }
455  eval_h = scale->var_values[VAR_OUT_H] = scale->var_values[VAR_OH] = (int) res == 0 ? inlink->h : (int) res;
456 
457  res = av_expr_eval(scale->w_pexpr, scale->var_values, NULL);
458  if (isnan(res)) {
459  expr = scale->w_expr;
460  ret = AVERROR(EINVAL);
461  goto fail;
462  }
463  eval_w = scale->var_values[VAR_OUT_W] = scale->var_values[VAR_OW] = (int) res == 0 ? inlink->w : (int) res;
464 
465  scale->w = eval_w;
466  scale->h = eval_h;
467 
468  return 0;
469 
470 fail:
472  "Error when evaluating the expression '%s'.\n", expr);
473  return ret;
474 }
475 
476 static int config_props(AVFilterLink *outlink)
477 {
478  AVFilterContext *ctx = outlink->src;
479  AVFilterLink *inlink0 = outlink->src->inputs[0];
480  AVFilterLink *inlink = ctx->filter == &ff_vf_scale2ref ?
481  outlink->src->inputs[1] :
482  outlink->src->inputs[0];
483  enum AVPixelFormat outfmt = outlink->format;
485  ScaleContext *scale = ctx->priv;
486  int ret;
487 
488  if ((ret = scale_eval_dimensions(ctx)) < 0)
489  goto fail;
490 
492  scale->force_original_aspect_ratio,
493  scale->force_divisible_by);
494 
495  if (scale->w > INT_MAX ||
496  scale->h > INT_MAX ||
497  (scale->h * inlink->w) > INT_MAX ||
498  (scale->w * inlink->h) > INT_MAX)
499  av_log(ctx, AV_LOG_ERROR, "Rescaled value for width or height is too big.\n");
500 
501  outlink->w = scale->w;
502  outlink->h = scale->h;
503 
504  /* TODO: make algorithm configurable */
505 
506  scale->input_is_pal = desc->flags & AV_PIX_FMT_FLAG_PAL;
507  if (outfmt == AV_PIX_FMT_PAL8) outfmt = AV_PIX_FMT_BGR8;
508  scale->output_is_pal = av_pix_fmt_desc_get(outfmt)->flags & AV_PIX_FMT_FLAG_PAL;
509 
510  if (scale->sws)
511  sws_freeContext(scale->sws);
512  if (scale->isws[0])
513  sws_freeContext(scale->isws[0]);
514  if (scale->isws[1])
515  sws_freeContext(scale->isws[1]);
516  scale->isws[0] = scale->isws[1] = scale->sws = NULL;
517  if (inlink0->w == outlink->w &&
518  inlink0->h == outlink->h &&
519  !scale->out_color_matrix &&
520  scale->in_range == scale->out_range &&
521  inlink0->format == outlink->format)
522  ;
523  else {
524  struct SwsContext **swscs[3] = {&scale->sws, &scale->isws[0], &scale->isws[1]};
525  int i;
526 
527  for (i = 0; i < 3; i++) {
528  int in_v_chr_pos = scale->in_v_chr_pos, out_v_chr_pos = scale->out_v_chr_pos;
529  struct SwsContext *const s = sws_alloc_context();
530  if (!s)
531  return AVERROR(ENOMEM);
532  *swscs[i] = s;
533 
534  av_opt_set_int(s, "srcw", inlink0 ->w, 0);
535  av_opt_set_int(s, "srch", inlink0 ->h >> !!i, 0);
536  av_opt_set_int(s, "src_format", inlink0->format, 0);
537  av_opt_set_int(s, "dstw", outlink->w, 0);
538  av_opt_set_int(s, "dsth", outlink->h >> !!i, 0);
539  av_opt_set_int(s, "dst_format", outfmt, 0);
540  av_opt_set_int(s, "sws_flags", scale->flags, 0);
541  av_opt_set_int(s, "param0", scale->param[0], 0);
542  av_opt_set_int(s, "param1", scale->param[1], 0);
543  av_opt_set_int(s, "threads", ff_filter_get_nb_threads(ctx), 0);
544  if (scale->in_range != AVCOL_RANGE_UNSPECIFIED)
545  av_opt_set_int(s, "src_range",
546  scale->in_range == AVCOL_RANGE_JPEG, 0);
547  if (scale->out_range != AVCOL_RANGE_UNSPECIFIED)
548  av_opt_set_int(s, "dst_range",
549  scale->out_range == AVCOL_RANGE_JPEG, 0);
550 
551  if (scale->opts) {
552  AVDictionaryEntry *e = NULL;
553  while ((e = av_dict_get(scale->opts, "", e, AV_DICT_IGNORE_SUFFIX))) {
554  if ((ret = av_opt_set(s, e->key, e->value, 0)) < 0)
555  return ret;
556  }
557  }
558  /* Override YUV420P default settings to have the correct (MPEG-2) chroma positions
559  * MPEG-2 chroma positions are used by convention
560  * XXX: support other 4:2:0 pixel formats */
561  if (inlink0->format == AV_PIX_FMT_YUV420P && scale->in_v_chr_pos == -513) {
562  in_v_chr_pos = (i == 0) ? 128 : (i == 1) ? 64 : 192;
563  }
564 
565  if (outlink->format == AV_PIX_FMT_YUV420P && scale->out_v_chr_pos == -513) {
566  out_v_chr_pos = (i == 0) ? 128 : (i == 1) ? 64 : 192;
567  }
568 
569  av_opt_set_int(s, "src_h_chr_pos", scale->in_h_chr_pos, 0);
570  av_opt_set_int(s, "src_v_chr_pos", in_v_chr_pos, 0);
571  av_opt_set_int(s, "dst_h_chr_pos", scale->out_h_chr_pos, 0);
572  av_opt_set_int(s, "dst_v_chr_pos", out_v_chr_pos, 0);
573 
574  if ((ret = sws_init_context(s, NULL, NULL)) < 0)
575  return ret;
576  if (!scale->interlaced)
577  break;
578  }
579  }
580 
581  if (inlink0->sample_aspect_ratio.num){
582  outlink->sample_aspect_ratio = av_mul_q((AVRational){outlink->h * inlink0->w, outlink->w * inlink0->h}, inlink0->sample_aspect_ratio);
583  } else
584  outlink->sample_aspect_ratio = inlink0->sample_aspect_ratio;
585 
586  av_log(ctx, AV_LOG_VERBOSE, "w:%d h:%d fmt:%s sar:%d/%d -> w:%d h:%d fmt:%s sar:%d/%d flags:0x%0x\n",
587  inlink ->w, inlink ->h, av_get_pix_fmt_name( inlink->format),
588  inlink->sample_aspect_ratio.num, inlink->sample_aspect_ratio.den,
589  outlink->w, outlink->h, av_get_pix_fmt_name(outlink->format),
590  outlink->sample_aspect_ratio.num, outlink->sample_aspect_ratio.den,
591  scale->flags);
592  return 0;
593 
594 fail:
595  return ret;
596 }
597 
598 static int config_props_ref(AVFilterLink *outlink)
599 {
600  AVFilterLink *inlink = outlink->src->inputs[1];
601 
602  outlink->w = inlink->w;
603  outlink->h = inlink->h;
604  outlink->sample_aspect_ratio = inlink->sample_aspect_ratio;
605  outlink->time_base = inlink->time_base;
606  outlink->frame_rate = inlink->frame_rate;
607 
608  return 0;
609 }
610 
611 static int request_frame(AVFilterLink *outlink)
612 {
613  return ff_request_frame(outlink->src->inputs[0]);
614 }
615 
616 static int request_frame_ref(AVFilterLink *outlink)
617 {
618  return ff_request_frame(outlink->src->inputs[1]);
619 }
620 
621 static void frame_offset(AVFrame *frame, int dir, int is_pal)
622 {
623  for (int i = 0; i < 4 && frame->data[i]; i++) {
624  if (i == 1 && is_pal)
625  break;
626  frame->data[i] += frame->linesize[i] * dir;
627  }
628 }
629 
631  int field)
632 {
633  int orig_h_src = src->height;
634  int orig_h_dst = dst->height;
635  int ret;
636 
637  // offset the data pointers for the bottom field
638  if (field) {
639  frame_offset(src, 1, scale->input_is_pal);
640  frame_offset(dst, 1, scale->output_is_pal);
641  }
642 
643  // take every second line
644  for (int i = 0; i < 4; i++) {
645  src->linesize[i] *= 2;
646  dst->linesize[i] *= 2;
647  }
648  src->height /= 2;
649  dst->height /= 2;
650 
651  ret = sws_scale_frame(scale->isws[field], dst, src);
652  if (ret < 0)
653  return ret;
654 
655  // undo the changes we made above
656  for (int i = 0; i < 4; i++) {
657  src->linesize[i] /= 2;
658  dst->linesize[i] /= 2;
659  }
660  src->height = orig_h_src;
661  dst->height = orig_h_dst;
662 
663  if (field) {
664  frame_offset(src, -1, scale->input_is_pal);
665  frame_offset(dst, -1, scale->output_is_pal);
666  }
667 
668  return 0;
669 }
670 
671 static int scale_frame(AVFilterLink *link, AVFrame *in, AVFrame **frame_out)
672 {
673  AVFilterContext *ctx = link->dst;
674  ScaleContext *scale = ctx->priv;
675  AVFilterLink *outlink = ctx->outputs[0];
676  AVFrame *out;
678  char buf[32];
679  int ret;
680  int in_range;
681  int frame_changed;
682 
683  *frame_out = NULL;
684  if (in->colorspace == AVCOL_SPC_YCGCO)
685  av_log(link->dst, AV_LOG_WARNING, "Detected unsupported YCgCo colorspace.\n");
686 
687  frame_changed = in->width != link->w ||
688  in->height != link->h ||
689  in->format != link->format ||
692 
693  if (scale->eval_mode == EVAL_MODE_FRAME || frame_changed) {
694  unsigned vars_w[VARS_NB] = { 0 }, vars_h[VARS_NB] = { 0 };
695 
696  av_expr_count_vars(scale->w_pexpr, vars_w, VARS_NB);
697  av_expr_count_vars(scale->h_pexpr, vars_h, VARS_NB);
698 
699  if (scale->eval_mode == EVAL_MODE_FRAME &&
700  !frame_changed &&
701  ctx->filter != &ff_vf_scale2ref &&
702  !(vars_w[VAR_N] || vars_w[VAR_T] || vars_w[VAR_POS]) &&
703  !(vars_h[VAR_N] || vars_h[VAR_T] || vars_h[VAR_POS]) &&
704  scale->w && scale->h)
705  goto scale;
706 
707  if (scale->eval_mode == EVAL_MODE_INIT) {
708  snprintf(buf, sizeof(buf)-1, "%d", outlink->w);
709  av_opt_set(scale, "w", buf, 0);
710  snprintf(buf, sizeof(buf)-1, "%d", outlink->h);
711  av_opt_set(scale, "h", buf, 0);
712 
713  ret = scale_parse_expr(ctx, NULL, &scale->w_pexpr, "width", scale->w_expr);
714  if (ret < 0)
715  return ret;
716 
717  ret = scale_parse_expr(ctx, NULL, &scale->h_pexpr, "height", scale->h_expr);
718  if (ret < 0)
719  return ret;
720  }
721 
722  if (ctx->filter == &ff_vf_scale2ref) {
723  scale->var_values[VAR_S2R_MAIN_N] = link->frame_count_out;
724  scale->var_values[VAR_S2R_MAIN_T] = TS2T(in->pts, link->time_base);
725  scale->var_values[VAR_S2R_MAIN_POS] = in->pkt_pos == -1 ? NAN : in->pkt_pos;
726  } else {
727  scale->var_values[VAR_N] = link->frame_count_out;
728  scale->var_values[VAR_T] = TS2T(in->pts, link->time_base);
729  scale->var_values[VAR_POS] = in->pkt_pos == -1 ? NAN : in->pkt_pos;
730  }
731 
732  link->dst->inputs[0]->format = in->format;
733  link->dst->inputs[0]->w = in->width;
734  link->dst->inputs[0]->h = in->height;
735 
736  link->dst->inputs[0]->sample_aspect_ratio.den = in->sample_aspect_ratio.den;
737  link->dst->inputs[0]->sample_aspect_ratio.num = in->sample_aspect_ratio.num;
738 
739  if ((ret = config_props(outlink)) < 0)
740  return ret;
741  }
742 
743 scale:
744  if (!scale->sws) {
745  *frame_out = in;
746  return 0;
747  }
748 
749  scale->hsub = desc->log2_chroma_w;
750  scale->vsub = desc->log2_chroma_h;
751 
752  out = ff_get_video_buffer(outlink, outlink->w, outlink->h);
753  if (!out) {
754  av_frame_free(&in);
755  return AVERROR(ENOMEM);
756  }
757  *frame_out = out;
758 
760  out->width = outlink->w;
761  out->height = outlink->h;
762 
763  // Sanity checks:
764  // 1. If the output is RGB, set the matrix coefficients to RGB.
765  // 2. If the output is not RGB and we've got the RGB/XYZ (identity)
766  // matrix configured, unset the matrix.
767  // In theory these should be in swscale itself as the AVFrame
768  // based API gets in, so that not every swscale API user has
769  // to go through duplicating such sanity checks.
771  out->colorspace = AVCOL_SPC_RGB;
772  else if (out->colorspace == AVCOL_SPC_RGB)
773  out->colorspace = AVCOL_SPC_UNSPECIFIED;
774 
775  if (scale->output_is_pal)
776  avpriv_set_systematic_pal2((uint32_t*)out->data[1], outlink->format == AV_PIX_FMT_PAL8 ? AV_PIX_FMT_BGR8 : outlink->format);
777 
778  in_range = in->color_range;
779 
780  if ( scale->in_color_matrix
781  || scale->out_color_matrix
782  || scale-> in_range != AVCOL_RANGE_UNSPECIFIED
783  || in_range != AVCOL_RANGE_UNSPECIFIED
784  || scale->out_range != AVCOL_RANGE_UNSPECIFIED) {
785  int in_full, out_full, brightness, contrast, saturation;
786  const int *inv_table, *table;
787 
788  sws_getColorspaceDetails(scale->sws, (int **)&inv_table, &in_full,
789  (int **)&table, &out_full,
791 
792  if (scale->in_color_matrix)
793  inv_table = parse_yuv_type(scale->in_color_matrix, in->colorspace);
794  if (scale->out_color_matrix)
795  table = parse_yuv_type(scale->out_color_matrix, AVCOL_SPC_UNSPECIFIED);
796  else if (scale->in_color_matrix)
797  table = inv_table;
798 
799  if (scale-> in_range != AVCOL_RANGE_UNSPECIFIED)
800  in_full = (scale-> in_range == AVCOL_RANGE_JPEG);
801  else if (in_range != AVCOL_RANGE_UNSPECIFIED)
802  in_full = (in_range == AVCOL_RANGE_JPEG);
803  if (scale->out_range != AVCOL_RANGE_UNSPECIFIED)
804  out_full = (scale->out_range == AVCOL_RANGE_JPEG);
805 
806  sws_setColorspaceDetails(scale->sws, inv_table, in_full,
807  table, out_full,
809  if (scale->isws[0])
810  sws_setColorspaceDetails(scale->isws[0], inv_table, in_full,
811  table, out_full,
813  if (scale->isws[1])
814  sws_setColorspaceDetails(scale->isws[1], inv_table, in_full,
815  table, out_full,
817 
818  out->color_range = out_full ? AVCOL_RANGE_JPEG : AVCOL_RANGE_MPEG;
819  }
820 
821  av_reduce(&out->sample_aspect_ratio.num, &out->sample_aspect_ratio.den,
822  (int64_t)in->sample_aspect_ratio.num * outlink->h * link->w,
823  (int64_t)in->sample_aspect_ratio.den * outlink->w * link->h,
824  INT_MAX);
825 
826  if (scale->interlaced>0 || (scale->interlaced<0 && in->interlaced_frame)) {
827  ret = scale_field(scale, out, in, 0);
828  if (ret >= 0)
829  ret = scale_field(scale, out, in, 1);
830  } else {
831  ret = sws_scale_frame(scale->sws, out, in);
832  }
833 
834  av_frame_free(&in);
835  if (ret < 0)
836  av_frame_free(frame_out);
837  return ret;
838 }
839 
841 {
842  AVFilterContext *ctx = link->dst;
843  AVFilterLink *outlink = ctx->outputs[0];
844  AVFrame *out;
845  int ret;
846 
847  ret = scale_frame(link, in, &out);
848  if (out)
849  return ff_filter_frame(outlink, out);
850 
851  return ret;
852 }
853 
855 {
856  ScaleContext *scale = link->dst->priv;
857  AVFilterLink *outlink = link->dst->outputs[1];
858  int frame_changed;
859 
860  frame_changed = in->width != link->w ||
861  in->height != link->h ||
862  in->format != link->format ||
865 
866  if (frame_changed) {
867  link->format = in->format;
868  link->w = in->width;
869  link->h = in->height;
872 
873  config_props_ref(outlink);
874  }
875 
876  if (scale->eval_mode == EVAL_MODE_FRAME) {
877  scale->var_values[VAR_N] = link->frame_count_out;
878  scale->var_values[VAR_T] = TS2T(in->pts, link->time_base);
879  scale->var_values[VAR_POS] = in->pkt_pos == -1 ? NAN : in->pkt_pos;
880  }
881 
882  return ff_filter_frame(outlink, in);
883 }
884 
885 static int process_command(AVFilterContext *ctx, const char *cmd, const char *args,
886  char *res, int res_len, int flags)
887 {
888  ScaleContext *scale = ctx->priv;
889  char *str_expr;
890  AVExpr **pexpr_ptr;
891  int ret, w, h;
892 
893  w = !strcmp(cmd, "width") || !strcmp(cmd, "w");
894  h = !strcmp(cmd, "height") || !strcmp(cmd, "h");
895 
896  if (w || h) {
897  str_expr = w ? scale->w_expr : scale->h_expr;
898  pexpr_ptr = w ? &scale->w_pexpr : &scale->h_pexpr;
899 
900  ret = scale_parse_expr(ctx, str_expr, pexpr_ptr, cmd, args);
901  } else
902  ret = AVERROR(ENOSYS);
903 
904  if (ret < 0)
905  av_log(ctx, AV_LOG_ERROR, "Failed to process command. Continuing with existing parameters.\n");
906 
907  return ret;
908 }
909 
910 static const AVClass *child_class_iterate(void **iter)
911 {
912  const AVClass *c = *iter ? NULL : sws_get_class();
913  *iter = (void*)(uintptr_t)c;
914  return c;
915 }
916 
917 #define OFFSET(x) offsetof(ScaleContext, x)
918 #define FLAGS AV_OPT_FLAG_VIDEO_PARAM|AV_OPT_FLAG_FILTERING_PARAM
919 #define TFLAGS AV_OPT_FLAG_VIDEO_PARAM|AV_OPT_FLAG_FILTERING_PARAM|AV_OPT_FLAG_RUNTIME_PARAM
920 
921 static const AVOption scale_options[] = {
922  { "w", "Output video width", OFFSET(w_expr), AV_OPT_TYPE_STRING, .flags = TFLAGS },
923  { "width", "Output video width", OFFSET(w_expr), AV_OPT_TYPE_STRING, .flags = TFLAGS },
924  { "h", "Output video height", OFFSET(h_expr), AV_OPT_TYPE_STRING, .flags = TFLAGS },
925  { "height","Output video height", OFFSET(h_expr), AV_OPT_TYPE_STRING, .flags = TFLAGS },
926  { "flags", "Flags to pass to libswscale", OFFSET(flags_str), AV_OPT_TYPE_STRING, { .str = "" }, .flags = FLAGS },
927  { "interl", "set interlacing", OFFSET(interlaced), AV_OPT_TYPE_BOOL, {.i64 = 0 }, -1, 1, FLAGS },
928  { "size", "set video size", OFFSET(size_str), AV_OPT_TYPE_STRING, {.str = NULL}, 0, FLAGS },
929  { "s", "set video size", OFFSET(size_str), AV_OPT_TYPE_STRING, {.str = NULL}, 0, FLAGS },
930  { "in_color_matrix", "set input YCbCr type", OFFSET(in_color_matrix), AV_OPT_TYPE_STRING, { .str = "auto" }, .flags = FLAGS, "color" },
931  { "out_color_matrix", "set output YCbCr type", OFFSET(out_color_matrix), AV_OPT_TYPE_STRING, { .str = NULL }, .flags = FLAGS, "color"},
932  { "auto", NULL, 0, AV_OPT_TYPE_CONST, { .str = "auto" }, 0, 0, FLAGS, "color" },
933  { "bt601", NULL, 0, AV_OPT_TYPE_CONST, { .str = "bt601" }, 0, 0, FLAGS, "color" },
934  { "bt470", NULL, 0, AV_OPT_TYPE_CONST, { .str = "bt470" }, 0, 0, FLAGS, "color" },
935  { "smpte170m", NULL, 0, AV_OPT_TYPE_CONST, { .str = "smpte170m" }, 0, 0, FLAGS, "color" },
936  { "bt709", NULL, 0, AV_OPT_TYPE_CONST, { .str = "bt709" }, 0, 0, FLAGS, "color" },
937  { "fcc", NULL, 0, AV_OPT_TYPE_CONST, { .str = "fcc" }, 0, 0, FLAGS, "color" },
938  { "smpte240m", NULL, 0, AV_OPT_TYPE_CONST, { .str = "smpte240m" }, 0, 0, FLAGS, "color" },
939  { "bt2020", NULL, 0, AV_OPT_TYPE_CONST, { .str = "bt2020" }, 0, 0, FLAGS, "color" },
940  { "in_range", "set input color range", OFFSET( in_range), AV_OPT_TYPE_INT, {.i64 = AVCOL_RANGE_UNSPECIFIED }, 0, 2, FLAGS, "range" },
941  { "out_range", "set output color range", OFFSET(out_range), AV_OPT_TYPE_INT, {.i64 = AVCOL_RANGE_UNSPECIFIED }, 0, 2, FLAGS, "range" },
942  { "auto", NULL, 0, AV_OPT_TYPE_CONST, {.i64 = AVCOL_RANGE_UNSPECIFIED }, 0, 0, FLAGS, "range" },
943  { "unknown", NULL, 0, AV_OPT_TYPE_CONST, {.i64 = AVCOL_RANGE_UNSPECIFIED }, 0, 0, FLAGS, "range" },
944  { "full", NULL, 0, AV_OPT_TYPE_CONST, {.i64 = AVCOL_RANGE_JPEG}, 0, 0, FLAGS, "range" },
945  { "limited",NULL, 0, AV_OPT_TYPE_CONST, {.i64 = AVCOL_RANGE_MPEG}, 0, 0, FLAGS, "range" },
946  { "jpeg", NULL, 0, AV_OPT_TYPE_CONST, {.i64 = AVCOL_RANGE_JPEG}, 0, 0, FLAGS, "range" },
947  { "mpeg", NULL, 0, AV_OPT_TYPE_CONST, {.i64 = AVCOL_RANGE_MPEG}, 0, 0, FLAGS, "range" },
948  { "tv", NULL, 0, AV_OPT_TYPE_CONST, {.i64 = AVCOL_RANGE_MPEG}, 0, 0, FLAGS, "range" },
949  { "pc", NULL, 0, AV_OPT_TYPE_CONST, {.i64 = AVCOL_RANGE_JPEG}, 0, 0, FLAGS, "range" },
950  { "in_v_chr_pos", "input vertical chroma position in luma grid/256" , OFFSET(in_v_chr_pos), AV_OPT_TYPE_INT, { .i64 = -513}, -513, 512, FLAGS },
951  { "in_h_chr_pos", "input horizontal chroma position in luma grid/256", OFFSET(in_h_chr_pos), AV_OPT_TYPE_INT, { .i64 = -513}, -513, 512, FLAGS },
952  { "out_v_chr_pos", "output vertical chroma position in luma grid/256" , OFFSET(out_v_chr_pos), AV_OPT_TYPE_INT, { .i64 = -513}, -513, 512, FLAGS },
953  { "out_h_chr_pos", "output horizontal chroma position in luma grid/256", OFFSET(out_h_chr_pos), AV_OPT_TYPE_INT, { .i64 = -513}, -513, 512, FLAGS },
954  { "force_original_aspect_ratio", "decrease or increase w/h if necessary to keep the original AR", OFFSET(force_original_aspect_ratio), AV_OPT_TYPE_INT, { .i64 = 0}, 0, 2, FLAGS, "force_oar" },
955  { "disable", NULL, 0, AV_OPT_TYPE_CONST, {.i64 = 0 }, 0, 0, FLAGS, "force_oar" },
956  { "decrease", NULL, 0, AV_OPT_TYPE_CONST, {.i64 = 1 }, 0, 0, FLAGS, "force_oar" },
957  { "increase", NULL, 0, AV_OPT_TYPE_CONST, {.i64 = 2 }, 0, 0, FLAGS, "force_oar" },
958  { "force_divisible_by", "enforce that the output resolution is divisible by a defined integer when force_original_aspect_ratio is used", OFFSET(force_divisible_by), AV_OPT_TYPE_INT, { .i64 = 1}, 1, 256, FLAGS },
959  { "param0", "Scaler param 0", OFFSET(param[0]), AV_OPT_TYPE_DOUBLE, { .dbl = SWS_PARAM_DEFAULT }, INT_MIN, INT_MAX, FLAGS },
960  { "param1", "Scaler param 1", OFFSET(param[1]), AV_OPT_TYPE_DOUBLE, { .dbl = SWS_PARAM_DEFAULT }, INT_MIN, INT_MAX, FLAGS },
961  { "eval", "specify when to evaluate expressions", OFFSET(eval_mode), AV_OPT_TYPE_INT, {.i64 = EVAL_MODE_INIT}, 0, EVAL_MODE_NB-1, FLAGS, "eval" },
962  { "init", "eval expressions once during initialization", 0, AV_OPT_TYPE_CONST, {.i64=EVAL_MODE_INIT}, .flags = FLAGS, .unit = "eval" },
963  { "frame", "eval expressions during initialization and per-frame", 0, AV_OPT_TYPE_CONST, {.i64=EVAL_MODE_FRAME}, .flags = FLAGS, .unit = "eval" },
964  { NULL }
965 };
966 
967 static const AVClass scale_class = {
968  .class_name = "scale(2ref)",
969  .item_name = av_default_item_name,
970  .option = scale_options,
971  .version = LIBAVUTIL_VERSION_INT,
972  .category = AV_CLASS_CATEGORY_FILTER,
973  .child_class_iterate = child_class_iterate,
974 };
975 
977  {
978  .name = "default",
979  .type = AVMEDIA_TYPE_VIDEO,
980  .filter_frame = filter_frame,
981  },
982 };
983 
985  {
986  .name = "default",
987  .type = AVMEDIA_TYPE_VIDEO,
988  .config_props = config_props,
989  },
990 };
991 
993  .name = "scale",
994  .description = NULL_IF_CONFIG_SMALL("Scale the input video size and/or convert the image format."),
995  .init_dict = init_dict,
996  .uninit = uninit,
997  .priv_size = sizeof(ScaleContext),
998  .priv_class = &scale_class,
1002  .process_command = process_command,
1003 };
1004 
1006  {
1007  .name = "default",
1008  .type = AVMEDIA_TYPE_VIDEO,
1009  .filter_frame = filter_frame,
1010  },
1011  {
1012  .name = "ref",
1013  .type = AVMEDIA_TYPE_VIDEO,
1014  .filter_frame = filter_frame_ref,
1015  },
1016 };
1017 
1019  {
1020  .name = "default",
1021  .type = AVMEDIA_TYPE_VIDEO,
1022  .config_props = config_props,
1023  .request_frame= request_frame,
1024  },
1025  {
1026  .name = "ref",
1027  .type = AVMEDIA_TYPE_VIDEO,
1028  .config_props = config_props_ref,
1029  .request_frame= request_frame_ref,
1030  },
1031 };
1032 
1034  .name = "scale2ref",
1035  .description = NULL_IF_CONFIG_SMALL("Scale the input video size and/or convert the image format to the given reference."),
1036  .init_dict = init_dict,
1037  .uninit = uninit,
1038  .priv_size = sizeof(ScaleContext),
1039  .priv_class = &scale_class,
1043  .process_command = process_command,
1044 };
filter_frame_ref
static int filter_frame_ref(AVFilterLink *link, AVFrame *in)
Definition: vf_scale.c:854
ScaleContext::param
double param[2]
sws flags
Definition: vf_scale.c:121
VAR_S2R_MAIN_SAR
@ VAR_S2R_MAIN_SAR
Definition: vf_scale.c:90
formats
formats
Definition: signature.h:48
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
VAR_S2R_MAIN_A
@ VAR_S2R_MAIN_A
Definition: vf_scale.c:89
VAR_HSUB
@ VAR_HSUB
Definition: vf_scale.c:80
config_props_ref
static int config_props_ref(AVFilterLink *outlink)
Definition: vf_scale.c:598
SwsContext::saturation
int saturation
Definition: swscale_internal.h:455
AV_LOG_WARNING
#define AV_LOG_WARNING
Something somehow does not look correct.
Definition: log.h:186
AVFrame::color_range
enum AVColorRange color_range
MPEG vs JPEG YUV range.
Definition: frame.h:566
sws_isSupportedOutput
#define sws_isSupportedOutput(x)
AVPixelFormat
AVPixelFormat
Pixel format.
Definition: pixfmt.h:64
TFLAGS
#define TFLAGS
Definition: vf_scale.c:919
sws_isSupportedInput
#define sws_isSupportedInput(x)
check_exprs
static int check_exprs(AVFilterContext *ctx)
Definition: vf_scale.c:159
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
ScaleContext::input_is_pal
int input_is_pal
set to 1 if the input format is paletted
Definition: vf_scale.c:125
out
FILE * out
Definition: movenc.c:54
ScaleContext
Definition: vf_scale.c:106
ScaleContext::flags
unsigned int flags
Definition: vf_scale.c:120
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_pix_fmt_desc_get
const AVPixFmtDescriptor * av_pix_fmt_desc_get(enum AVPixelFormat pix_fmt)
Definition: pixdesc.c:2660
query_formats
static int query_formats(AVFilterContext *ctx)
Definition: vf_scale.c:341
ScaleContext::force_divisible_by
int force_divisible_by
Definition: vf_scale.c:149
avfilter_vf_scale2ref_outputs
static const AVFilterPad avfilter_vf_scale2ref_outputs[]
Definition: vf_scale.c:1018
FLAGS
#define FLAGS
Definition: vf_scale.c:918
ScaleContext::flags_str
char * flags_str
Definition: vf_scale.c:135
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
av_frame_free
void av_frame_free(AVFrame **frame)
Free the frame and any dynamically allocated objects in it, e.g.
Definition: frame.c:109
AVFrame::colorspace
enum AVColorSpace colorspace
YUV colorspace type.
Definition: frame.h:577
AVFrame
This structure describes decoded (raw) audio or video data.
Definition: frame.h:317
pixdesc.h
AVFrame::pts
int64_t pts
Presentation timestamp in time_base units (time when frame should be shown to user).
Definition: frame.h:424
AVFrame::width
int width
Definition: frame.h:389
w
uint8_t w
Definition: llviddspenc.c:38
AVCOL_RANGE_JPEG
@ AVCOL_RANGE_JPEG
Full range content.
Definition: pixfmt.h:597
VAR_A
@ VAR_A
Definition: vf_scale.c:77
request_frame_ref
static int request_frame_ref(AVFilterLink *outlink)
Definition: vf_scale.c:616
AVOption
AVOption.
Definition: opt.h:247
scale_parse_expr
static int scale_parse_expr(AVFilterContext *ctx, char *str_expr, AVExpr **pexpr_ptr, const char *var, const char *args)
Definition: vf_scale.c:217
FILTER_QUERY_FUNC
#define FILTER_QUERY_FUNC(func)
Definition: internal.h:168
table
static const uint16_t table[]
Definition: prosumer.c:206
request_frame
static int request_frame(AVFilterLink *outlink)
Definition: vf_scale.c:611
av_pix_fmt_desc_next
const AVPixFmtDescriptor * av_pix_fmt_desc_next(const AVPixFmtDescriptor *prev)
Iterate over all pixel format descriptors known to libavutil.
Definition: pixdesc.c:2667
ff_request_frame
int ff_request_frame(AVFilterLink *link)
Request an input frame from the filter at the other end of the link.
Definition: avfilter.c:420
AV_DICT_IGNORE_SUFFIX
#define AV_DICT_IGNORE_SUFFIX
Return first entry in a dictionary whose first part corresponds to the search key,...
Definition: dict.h:68
VAR_S2R_MAIN_HSUB
@ VAR_S2R_MAIN_HSUB
Definition: vf_scale.c:92
ScaleContext::var_values
double var_values[VARS_NB]
Definition: vf_scale.c:133
ScaleContext::out_range
int out_range
Definition: vf_scale.c:141
VAR_S2R_MDAR
@ VAR_S2R_MDAR
Definition: vf_scale.c:91
AV_LOG_VERBOSE
#define AV_LOG_VERBOSE
Detailed information.
Definition: log.h:196
AVCOL_SPC_RGB
@ AVCOL_SPC_RGB
order of coefficients is actually GBR, also IEC 61966-2-1 (sRGB), YZX and ST 428-1
Definition: pixfmt.h:524
EVAL_MODE_FRAME
@ EVAL_MODE_FRAME
Definition: vf_scale.c:102
VAR_S2R_MAIN_H
@ VAR_S2R_MAIN_H
Definition: vf_scale.c:88
mathematics.h
AVDictionary
Definition: dict.c:30
AVFilter::name
const char * name
Filter name.
Definition: avfilter.h:169
ScaleContext::in_h_chr_pos
int in_h_chr_pos
Definition: vf_scale.c:145
VAR_OUT_H
@ VAR_OUT_H
Definition: vf_scale.c:76
ScaleContext::opts
AVDictionary * opts
Definition: vf_scale.c:110
video.h
AVFilterFormats
A list of supported formats for one end of a filter link.
Definition: formats.h:64
formats.h
av_expr_parse
int av_expr_parse(AVExpr **expr, const char *s, const char *const *const_names, const char *const *func1_names, double(*const *funcs1)(void *, double), const char *const *func2_names, double(*const *funcs2)(void *, double, double), int log_offset, void *log_ctx)
Parse an expression.
Definition: eval.c:685
VAR_S2R_MAIN_POS
@ VAR_S2R_MAIN_POS
Definition: vf_scale.c:96
AVCOL_SPC_BT470BG
@ AVCOL_SPC_BT470BG
also ITU-R BT601-6 625 / ITU-R BT1358 625 / ITU-R BT1700 625 PAL & SECAM / IEC 61966-2-4 xvYCC601
Definition: pixfmt.h:529
VAR_DAR
@ VAR_DAR
Definition: vf_scale.c:79
avfilter_vf_scale_inputs
static const AVFilterPad avfilter_vf_scale_inputs[]
Definition: vf_scale.c:976
fail
#define fail()
Definition: checkasm.h:128
VARS_NB
@ VARS_NB
Definition: vf_scale.c:97
frame_offset
static void frame_offset(AVFrame *frame, int dir, int is_pal)
Definition: vf_scale.c:621
ScaleContext::isws
struct SwsContext * isws[2]
software scaler context for interlaced material
Definition: vf_scale.c:109
ScaleContext::eval_mode
int eval_mode
expression evaluation mode
Definition: vf_scale.c:151
VAR_IN_H
@ VAR_IN_H
Definition: vf_scale.c:74
EVAL_MODE_NB
@ EVAL_MODE_NB
Definition: vf_scale.c:103
scale
static av_always_inline float scale(float x, float s)
Definition: vf_v360.c:1388
sws_get_class
const AVClass * sws_get_class(void)
Get the AVClass for swsContext.
Definition: options.c:99
av_opt_set
int av_opt_set(void *obj, const char *name, const char *val, int search_flags)
Definition: opt.c:468
av_reduce
int av_reduce(int *dst_num, int *dst_den, int64_t num, int64_t den, int64_t max)
Reduce a fraction.
Definition: rational.c:35
av_expr_free
void av_expr_free(AVExpr *e)
Free a parsed expression previously created with av_expr_parse().
Definition: eval.c:336
AVRational::num
int num
Numerator.
Definition: rational.h:59
OFFSET
#define OFFSET(x)
Definition: vf_scale.c:917
AVFilterPad
A filter pad used for either input or output.
Definition: internal.h:50
AV_PIX_FMT_BGR8
@ AV_PIX_FMT_BGR8
packed RGB 3:3:2, 8bpp, (msb)2B 3G 3R(lsb)
Definition: pixfmt.h:83
TS2T
#define TS2T(ts, tb)
Definition: internal.h:264
AV_LOG_ERROR
#define AV_LOG_ERROR
Something went wrong and cannot losslessly be recovered.
Definition: log.h:180
av_cold
#define av_cold
Definition: attributes.h:90
ScaleContext::sws
struct SwsContext * sws
software scaler context
Definition: vf_scale.c:108
av_dict_get
AVDictionaryEntry * av_dict_get(const AVDictionary *m, const char *key, const AVDictionaryEntry *prev, int flags)
Get a dictionary entry with matching key.
Definition: dict.c:40
s
#define s(width, name)
Definition: cbs_vp9.c:257
VAR_OH
@ VAR_OH
Definition: vf_scale.c:76
VAR_S2R_MAIN_W
@ VAR_S2R_MAIN_W
Definition: vf_scale.c:87
SwsContext::brightness
int brightness
Definition: swscale_internal.h:455
scale_frame
static int scale_frame(AVFilterLink *link, AVFrame *in, AVFrame **frame_out)
Definition: vf_scale.c:671
ScaleContext::slice_y
int slice_y
top of current output slice
Definition: vf_scale.c:124
AVFrame::pkt_pos
int64_t pkt_pos
reordered pos from the last AVPacket that has been input into the decoder
Definition: frame.h:593
AVDictionaryEntry::key
char * key
Definition: dict.h:80
AV_OPT_TYPE_DOUBLE
@ AV_OPT_TYPE_DOUBLE
Definition: opt.h:226
av_expr_count_vars
int av_expr_count_vars(AVExpr *e, unsigned *counter, int size)
Track the presence of variables and their number of occurrences in a parsed expression.
Definition: eval.c:756
ff_formats_ref
int ff_formats_ref(AVFilterFormats *f, AVFilterFormats **ref)
Add *ref as a new reference to formats.
Definition: formats.c:555
init_dict
static av_cold int init_dict(AVFilterContext *ctx, AVDictionary **opts)
Definition: vf_scale.c:270
VAR_OVSUB
@ VAR_OVSUB
Definition: vf_scale.c:83
ScaleContext::in_color_matrix
char * in_color_matrix
Definition: vf_scale.c:137
var_name
var_name
Definition: noise_bsf.c:47
ctx
AVFormatContext * ctx
Definition: movenc.c:48
process_command
static int process_command(AVFilterContext *ctx, const char *cmd, const char *args, char *res, int res_len, int flags)
Definition: vf_scale.c:885
av_expr_eval
double av_expr_eval(AVExpr *e, const double *const_values, void *opaque)
Evaluate a previously parsed expression.
Definition: eval.c:766
pix_fmt
static enum AVPixelFormat pix_fmt
Definition: demuxing_decoding.c:41
AVExpr
Definition: eval.c:157
field
it s the only field you need to keep assuming you have a context There is some magic you don t need to care about around this field
Definition: writing_filters.txt:78
AVPixFmtDescriptor::log2_chroma_w
uint8_t log2_chroma_w
Amount to shift the luma width right to find the chroma width.
Definition: pixdesc.h:80
AV_PIX_FMT_YUV420P
@ AV_PIX_FMT_YUV420P
planar YUV 4:2:0, 12bpp, (1 Cr & Cb sample per 2x2 Y samples)
Definition: pixfmt.h:66
SwsContext::contrast
int contrast
Definition: swscale_internal.h:455
ScaleContext::w_pexpr
AVExpr * w_pexpr
Definition: vf_scale.c:131
avpriv_set_systematic_pal2
int avpriv_set_systematic_pal2(uint32_t pal[256], enum AVPixelFormat pix_fmt)
Definition: imgutils.c:178
NAN
#define NAN
Definition: mathematics.h:64
FILTER_INPUTS
#define FILTER_INPUTS(array)
Definition: internal.h:191
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
av_opt_find
const AVOption * av_opt_find(void *obj, const char *name, const char *unit, int opt_flags, int search_flags)
Look for an option in an object.
Definition: opt.c:1666
ScaleContext::out_h_chr_pos
int out_h_chr_pos
Definition: vf_scale.c:143
scale_field
static int scale_field(ScaleContext *scale, AVFrame *dst, AVFrame *src, int field)
Definition: vf_scale.c:630
opts
AVDictionary * opts
Definition: movenc.c:50
LIBAVUTIL_VERSION_INT
#define LIBAVUTIL_VERSION_INT
Definition: version.h:85
AVClass
Describe the class of an AVClass context structure.
Definition: log.h:66
NULL
#define NULL
Definition: coverity.c:32
ScaleContext::out_v_chr_pos
int out_v_chr_pos
Definition: vf_scale.c:144
av_frame_copy_props
int av_frame_copy_props(AVFrame *dst, const AVFrame *src)
Copy only "metadata" fields from src to dst.
Definition: frame.c:537
VAR_T
@ VAR_T
Definition: vf_scale.c:85
AVRational
Rational number (pair of numerator and denominator).
Definition: rational.h:58
isnan
#define isnan(x)
Definition: libm.h:340
ScaleContext::in_range
int in_range
Definition: vf_scale.c:140
AVFilterContext::inputs
AVFilterLink ** inputs
array of pointers to input links
Definition: avfilter.h:410
VAR_IN_W
@ VAR_IN_W
Definition: vf_scale.c:73
av_default_item_name
const char * av_default_item_name(void *ptr)
Return the context name.
Definition: log.c:235
ff_add_format
int ff_add_format(AVFilterFormats **avff, int64_t fmt)
Add fmt to the list of media formats contained in *avff.
Definition: formats.c:420
parseutils.h
sws_alloc_context
struct SwsContext * sws_alloc_context(void)
Allocate an empty SwsContext.
Definition: utils.c:1154
ScaleContext::h_pexpr
AVExpr * h_pexpr
Definition: vf_scale.c:132
AVCOL_SPC_YCGCO
@ AVCOL_SPC_YCGCO
used by Dirac / VC-2 and H.264 FRext, see ITU-T SG16
Definition: pixfmt.h:532
sws_setColorspaceDetails
int sws_setColorspaceDetails(struct SwsContext *c, const int inv_table[4], int srcRange, const int table[4], int dstRange, int brightness, int contrast, int saturation)
Definition: utils.c:911
AVPixFmtDescriptor::flags
uint64_t flags
Combination of AV_PIX_FMT_FLAG_...
Definition: pixdesc.h:94
ff_vf_scale2ref
const AVFilter ff_vf_scale2ref
Definition: vf_scale.c:155
AVCOL_RANGE_UNSPECIFIED
@ AVCOL_RANGE_UNSPECIFIED
Definition: pixfmt.h:563
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
av_opt_set_int
int av_opt_set_int(void *obj, const char *name, int64_t val, int search_flags)
Definition: opt.c:589
AV_OPT_SEARCH_FAKE_OBJ
#define AV_OPT_SEARCH_FAKE_OBJ
The obj passed to av_opt_find() is fake – only a double pointer to AVClass instead of a required poin...
Definition: opt.h:567
AV_CLASS_CATEGORY_FILTER
@ AV_CLASS_CATEGORY_FILTER
Definition: log.h:36
VAR_IW
@ VAR_IW
Definition: vf_scale.c:73
SWS_PARAM_DEFAULT
#define SWS_PARAM_DEFAULT
Definition: swscale.h:74
eval.h
VAR_IH
@ VAR_IH
Definition: vf_scale.c:74
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
AV_PIX_FMT_FLAG_RGB
#define AV_PIX_FMT_FLAG_RGB
The pixel format contains RGB-like data (as opposed to YUV/grayscale).
Definition: pixdesc.h:136
child_class_iterate
static const AVClass * child_class_iterate(void **iter)
Definition: vf_scale.c:910
ScaleContext::w
int w
New dimensions.
Definition: vf_scale.c:118
AVFrame::time_base
AVRational time_base
Time base for the timestamps in this frame.
Definition: frame.h:439
AVFrame::format
int format
format of the frame, -1 if unknown or unset Values correspond to enum AVPixelFormat for video frames,...
Definition: frame.h:404
scale_eval.h
ScaleContext::hsub
int hsub
Definition: vf_scale.c:123
VAR_OUT_W
@ VAR_OUT_W
Definition: vf_scale.c:75
av_pix_fmt_desc_get_id
enum AVPixelFormat av_pix_fmt_desc_get_id(const AVPixFmtDescriptor *desc)
Definition: pixdesc.c:2679
av_dict_free
void av_dict_free(AVDictionary **pm)
Free all the memory allocated for an AVDictionary struct and all keys and values.
Definition: dict.c:203
filter_frame
static int filter_frame(AVFilterLink *link, AVFrame *in)
Definition: vf_scale.c:840
av_parse_video_size
int av_parse_video_size(int *width_ptr, int *height_ptr, const char *str)
Parse str and put in width_ptr and height_ptr the detected values.
Definition: parseutils.c:150
internal.h
VAR_POS
@ VAR_POS
Definition: vf_scale.c:86
AVCOL_SPC_SMPTE240M
@ AVCOL_SPC_SMPTE240M
derived from 170M primaries and D65 white point, 170M is derived from BT470 System M's primaries
Definition: pixfmt.h:531
AVFrame::interlaced_frame
int interlaced_frame
The content of the picture is interlaced.
Definition: frame.h:469
ScaleContext::vsub
int vsub
chroma subsampling
Definition: vf_scale.c:123
sws_scale_frame
int sws_scale_frame(struct SwsContext *c, AVFrame *dst, const AVFrame *src)
Scale source data from src and write the output to dst.
Definition: swscale.c:1183
config_props
static int config_props(AVFilterLink *outlink)
Definition: vf_scale.c:476
interlaced
uint8_t interlaced
Definition: mxfenc.c:2040
ScaleContext::output_is_pal
int output_is_pal
set to 1 if the output format is paletted
Definition: vf_scale.c:126
VAR_SAR
@ VAR_SAR
Definition: vf_scale.c:78
sws_isSupportedEndiannessConversion
int sws_isSupportedEndiannessConversion(enum AVPixelFormat pix_fmt)
Definition: utils.c:328
i
#define i(width, name, range_min, range_max)
Definition: cbs_h2645.c:271
AVCOL_SPC_BT2020_NCL
@ AVCOL_SPC_BT2020_NCL
ITU-R BT2020 non-constant luminance system.
Definition: pixfmt.h:534
VAR_S2R_MAIN_N
@ VAR_S2R_MAIN_N
Definition: vf_scale.c:94
internal.h
AVColorSpace
AVColorSpace
YUV colorspace type.
Definition: pixfmt.h:523
ff_filter_get_nb_threads
int ff_filter_get_nb_threads(AVFilterContext *ctx)
Get number of threads for current filter instance.
Definition: avfilter.c:803
EvalMode
EvalMode
Definition: af_volume.h:39
AVFilterPad::name
const char * name
Pad name.
Definition: internal.h:56
AVCOL_SPC_UNSPECIFIED
@ AVCOL_SPC_UNSPECIFIED
Definition: pixfmt.h:526
ScaleContext::h_expr
char * h_expr
height expression string
Definition: vf_scale.c:130
AVCOL_RANGE_MPEG
@ AVCOL_RANGE_MPEG
Narrow or limited range content.
Definition: pixfmt.h:580
avfilter_vf_scale_outputs
static const AVFilterPad avfilter_vf_scale_outputs[]
Definition: vf_scale.c:984
AVFilter
Filter definition.
Definition: avfilter.h:165
av_opt_eval_flags
int av_opt_eval_flags(void *obj, const AVOption *o, const char *val, int *flags_out)
AV_PIX_FMT_PAL8
@ AV_PIX_FMT_PAL8
8 bits with AV_PIX_FMT_RGB32 palette
Definition: pixfmt.h:77
ret
ret
Definition: filter_design.txt:187
FFSWAP
#define FFSWAP(type, a, b)
Definition: macros.h:52
AVClass::class_name
const char * class_name
The name of the class; usually it is the same name as the context structure type to which the AVClass...
Definition: log.h:71
frame
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 the filter must be ready for frames arriving randomly on any input any filter with several inputs will most likely require some kind of queuing mechanism It is perfectly acceptable to have a limited queue and to drop frames when the inputs are too unbalanced request_frame For filters that do not use the this method is called when a frame is wanted on an output For a it should directly call filter_frame on the corresponding output For a if there are queued frames already one of these frames should be pushed If the filter should request a frame on one of its repeatedly until at least one frame has been pushed Return or at least make progress towards producing a frame
Definition: filter_design.txt:264
parse_yuv_type
static const int * parse_yuv_type(const char *s, enum AVColorSpace colorspace)
Definition: vf_scale.c:377
AVFrame::sample_aspect_ratio
AVRational sample_aspect_ratio
Sample aspect ratio for the video frame, 0/1 if unknown/unspecified.
Definition: frame.h:419
sws_getColorspaceDetails
int sws_getColorspaceDetails(struct SwsContext *c, int **inv_table, int *srcRange, int **table, int *dstRange, int *brightness, int *contrast, int *saturation)
if LIBSWSCALE_VERSION_MAJOR > 6
Definition: utils.c:1062
ff_scale_adjust_dimensions
int ff_scale_adjust_dimensions(AVFilterLink *inlink, int *ret_w, int *ret_h, int force_original_aspect_ratio, int force_divisible_by)
Transform evaluated width and height obtained from ff_scale_eval_dimensions into actual target width ...
Definition: scale_eval.c:113
sws_init_context
av_warn_unused_result int sws_init_context(struct SwsContext *sws_context, SwsFilter *srcFilter, SwsFilter *dstFilter)
Initialize the swscaler context sws_context.
Definition: utils.c:1296
VAR_S2R_MAIN_T
@ VAR_S2R_MAIN_T
Definition: vf_scale.c:95
ScaleContext::out_color_matrix
char * out_color_matrix
Definition: vf_scale.c:138
scale_eval_dimensions
static int scale_eval_dimensions(AVFilterContext *ctx)
Definition: vf_scale.c:401
var_names
static const char *const var_names[]
Definition: vf_scale.c:44
AVFrame::height
int height
Definition: frame.h:389
VAR_S2R_MAIN_DAR
@ VAR_S2R_MAIN_DAR
Definition: vf_scale.c:91
scale_options
static const AVOption scale_options[]
Definition: vf_scale.c:921
sws_freeContext
void sws_freeContext(struct SwsContext *swsContext)
Free the swscaler context swsContext.
Definition: utils.c:2383
AVRational::den
int den
Denominator.
Definition: rational.h:60
AVCOL_SPC_FCC
@ AVCOL_SPC_FCC
FCC Title 47 Code of Federal Regulations 73.682 (a)(20)
Definition: pixfmt.h:528
AV_OPT_TYPE_INT
@ AV_OPT_TYPE_INT
Definition: opt.h:224
avfilter.h
uninit
static av_cold void uninit(AVFilterContext *ctx)
Definition: vf_scale.c:328
ScaleContext::force_original_aspect_ratio
int force_original_aspect_ratio
Definition: vf_scale.c:148
avfilter_vf_scale2ref_inputs
static const AVFilterPad avfilter_vf_scale2ref_inputs[]
Definition: vf_scale.c:1005
av_mul_q
AVRational av_mul_q(AVRational b, AVRational c)
Multiply two rationals.
Definition: rational.c:80
AVFilterContext
An instance of a filter.
Definition: avfilter.h:402
VAR_OW
@ VAR_OW
Definition: vf_scale.c:75
av_strdup
char * av_strdup(const char *s)
Duplicate a string.
Definition: mem.c:279
desc
const char * desc
Definition: libsvtav1.c:79
VAR_VSUB
@ VAR_VSUB
Definition: vf_scale.c:81
AVMEDIA_TYPE_VIDEO
@ AVMEDIA_TYPE_VIDEO
Definition: avutil.h:201
sws_getCoefficients
const int * sws_getCoefficients(int colorspace)
Return a pointer to yuv<->rgb coefficients for the given colorspace suitable for sws_setColorspaceDet...
Definition: yuv2rgb.c:62
AVPixFmtDescriptor
Descriptor that unambiguously describes how the bits of a pixel are stored in the up to 4 data planes...
Definition: pixdesc.h:69
ScaleContext::interlaced
int interlaced
Definition: vf_scale.c:127
av_free
#define av_free(p)
Definition: tableprint_vlc.h:34
AVDictionaryEntry
Definition: dict.h:79
VAR_N
@ VAR_N
Definition: vf_scale.c:84
AV_OPT_TYPE_BOOL
@ AV_OPT_TYPE_BOOL
Definition: opt.h:241
FILTER_OUTPUTS
#define FILTER_OUTPUTS(array)
Definition: internal.h:192
av_freep
#define av_freep(p)
Definition: tableprint_vlc.h:35
src
INIT_CLIP pixel * src
Definition: h264pred_template.c:418
scale_class
static const AVClass scale_class
Definition: vf_scale.c:967
ScaleContext::w_expr
char * w_expr
width expression string
Definition: vf_scale.c:129
EVAL_MODE_INIT
@ EVAL_MODE_INIT
Definition: vf_scale.c:101
imgutils.h
flags
#define flags(name, subs,...)
Definition: cbs_av1.c:561
AVFrame::linesize
int linesize[AV_NUM_DATA_POINTERS]
For video, a positive or negative value, which is typically indicating the size in bytes of each pict...
Definition: frame.h:362
av_log
#define av_log(a,...)
Definition: tableprint_vlc.h:28
h
h
Definition: vp9dsp_template.c:2038
AVDictionaryEntry::value
char * value
Definition: dict.h:81
avstring.h
AV_OPT_TYPE_STRING
@ AV_OPT_TYPE_STRING
Definition: opt.h:228
VAR_OHSUB
@ VAR_OHSUB
Definition: vf_scale.c:82
AVCOL_SPC_BT709
@ AVCOL_SPC_BT709
also ITU-R BT1361 / IEC 61966-2-4 xvYCC709 / derived in SMPTE RP 177 Annex B
Definition: pixfmt.h:525
int
int
Definition: ffmpeg_filter.c:153
SwsContext
Definition: swscale_internal.h:300
AV_PIX_FMT_FLAG_PAL
#define AV_PIX_FMT_FLAG_PAL
Pixel format has a palette in data[1], values are indexes in this palette.
Definition: pixdesc.h:120
AV_OPT_TYPE_CONST
@ AV_OPT_TYPE_CONST
Definition: opt.h:233
ff_vf_scale
const AVFilter ff_vf_scale
Definition: vf_scale.c:992
snprintf
#define snprintf
Definition: snprintf.h:34
ScaleContext::size_str
char * size_str
Definition: vf_scale.c:119
VAR_S2R_MAIN_VSUB
@ VAR_S2R_MAIN_VSUB
Definition: vf_scale.c:93
AVPixFmtDescriptor::log2_chroma_h
uint8_t log2_chroma_h
Amount to shift the luma height right to find the chroma height.
Definition: pixdesc.h:89
swscale.h
ScaleContext::h
int h
Definition: vf_scale.c:118
av_x_if_null
static void * av_x_if_null(const void *p, const void *x)
Return x default pointer in case p is NULL.
Definition: avutil.h:308
av_get_pix_fmt_name
const char * av_get_pix_fmt_name(enum AVPixelFormat pix_fmt)
Return the short name for a pixel format, NULL in case pix_fmt is unknown.
Definition: pixdesc.c:2580
ScaleContext::in_v_chr_pos
int in_v_chr_pos
Definition: vf_scale.c:146
SwsContext::param
double param[2]
Input parameters for scaling algorithms that need them.
Definition: swscale_internal.h:343