vf_drawtext.c
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1 /*
2  * Copyright (c) 2011 Stefano Sabatini
3  * Copyright (c) 2010 S.N. Hemanth Meenakshisundaram
4  * Copyright (c) 2003 Gustavo Sverzut Barbieri <gsbarbieri@yahoo.com.br>
5  *
6  * This file is part of Libav.
7  *
8  * Libav 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  * Libav 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 Libav; if not, write to the Free Software
20  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
21  */
22 
29 #include <sys/time.h>
30 #include <time.h>
31 
32 #include "libavutil/colorspace.h"
33 #include "libavutil/common.h"
34 #include "libavutil/file.h"
35 #include "libavutil/eval.h"
36 #include "libavutil/opt.h"
37 #include "libavutil/mathematics.h"
38 #include "libavutil/random_seed.h"
39 #include "libavutil/parseutils.h"
40 #include "libavutil/pixdesc.h"
41 #include "libavutil/tree.h"
42 #include "libavutil/lfg.h"
43 #include "avfilter.h"
44 #include "drawutils.h"
45 #include "formats.h"
46 #include "internal.h"
47 #include "video.h"
48 
49 #include <ft2build.h>
50 #include <freetype/config/ftheader.h>
51 #include FT_FREETYPE_H
52 #include FT_GLYPH_H
53 
54 static const char *const var_names[] = {
55  "E",
56  "PHI",
57  "PI",
58  "main_w", "W",
59  "main_h", "H",
60  "text_w", "w",
61  "text_h", "h",
62  "x",
63  "y",
64  "n",
65  "t",
66  NULL
67 };
68 
69 static const char *const fun2_names[] = {
70  "rand"
71 };
72 
73 static double drand(void *opaque, double min, double max)
74 {
75  return min + (max-min) / UINT_MAX * av_lfg_get(opaque);
76 }
77 
78 typedef double (*eval_func2)(void *, double a, double b);
79 
80 static const eval_func2 fun2[] = {
81  drand,
82  NULL
83 };
84 
85 enum var_name {
98 };
99 
100 typedef struct {
101  const AVClass *class;
107  FT_Vector *positions;
108  size_t nb_positions;
109  char *textfile;
110  int x, y;
111  int w, h;
112  int shadowx, shadowy;
113  unsigned int fontsize;
117  uint8_t fontcolor[4];
118  uint8_t boxcolor[4];
119  uint8_t shadowcolor[4];
120  uint8_t fontcolor_rgba[4];
121  uint8_t boxcolor_rgba[4];
122  uint8_t shadowcolor_rgba[4];
123 
124  short int draw_box;
126  int tabsize;
128 
129  FT_Library library;
130  FT_Face face;
131  struct AVTreeNode *glyphs;
132  int hsub, vsub;
134  int pixel_step[4];
135  uint8_t rgba_map[4];
136  uint8_t *box_line[4];
137  char *x_expr, *y_expr;
138  AVExpr *x_pexpr, *y_pexpr;
139  double var_values[VAR_VARS_NB];
140  char *d_expr;
142  int draw;
145 
146 #define OFFSET(x) offsetof(DrawTextContext, x)
147 
148 static const AVOption drawtext_options[]= {
149 {"fontfile", "set font file", OFFSET(fontfile), AV_OPT_TYPE_STRING, {.str=NULL}, CHAR_MIN, CHAR_MAX },
150 {"text", "set text", OFFSET(text), AV_OPT_TYPE_STRING, {.str=NULL}, CHAR_MIN, CHAR_MAX },
151 {"textfile", "set text file", OFFSET(textfile), AV_OPT_TYPE_STRING, {.str=NULL}, CHAR_MIN, CHAR_MAX },
152 {"fontcolor","set foreground color", OFFSET(fontcolor_string), AV_OPT_TYPE_STRING, {.str=NULL}, CHAR_MIN, CHAR_MAX },
153 {"boxcolor", "set box color", OFFSET(boxcolor_string), AV_OPT_TYPE_STRING, {.str=NULL}, CHAR_MIN, CHAR_MAX },
154 {"shadowcolor", "set shadow color", OFFSET(shadowcolor_string), AV_OPT_TYPE_STRING, {.str=NULL}, CHAR_MIN, CHAR_MAX },
155 {"box", "set box", OFFSET(draw_box), AV_OPT_TYPE_INT, {.i64=0}, 0, 1 },
156 {"fontsize", "set font size", OFFSET(fontsize), AV_OPT_TYPE_INT, {.i64=16}, 1, 72 },
157 {"x", "set x", OFFSET(x_expr), AV_OPT_TYPE_STRING, {.str="0"}, CHAR_MIN, CHAR_MAX },
158 {"y", "set y", OFFSET(y_expr), AV_OPT_TYPE_STRING, {.str="0"}, CHAR_MIN, CHAR_MAX },
159 {"shadowx", "set x", OFFSET(shadowx), AV_OPT_TYPE_INT, {.i64=0}, INT_MIN, INT_MAX },
160 {"shadowy", "set y", OFFSET(shadowy), AV_OPT_TYPE_INT, {.i64=0}, INT_MIN, INT_MAX },
161 {"tabsize", "set tab size", OFFSET(tabsize), AV_OPT_TYPE_INT, {.i64=4}, 0, INT_MAX },
162 {"draw", "if false do not draw", OFFSET(d_expr), AV_OPT_TYPE_STRING, {.str="1"}, CHAR_MIN, CHAR_MAX },
163 {"fix_bounds", "if true, check and fix text coords to avoid clipping",
164  OFFSET(fix_bounds), AV_OPT_TYPE_INT, {.i64=1}, 0, 1 },
165 
166 /* FT_LOAD_* flags */
167 {"ft_load_flags", "set font loading flags for libfreetype", OFFSET(ft_load_flags), AV_OPT_TYPE_FLAGS, {.i64=FT_LOAD_DEFAULT|FT_LOAD_RENDER}, 0, INT_MAX, 0, "ft_load_flags" },
168 {"default", "set default", 0, AV_OPT_TYPE_CONST, {.i64 = FT_LOAD_DEFAULT}, INT_MIN, INT_MAX, 0, "ft_load_flags" },
169 {"no_scale", "set no_scale", 0, AV_OPT_TYPE_CONST, {.i64 = FT_LOAD_NO_SCALE}, INT_MIN, INT_MAX, 0, "ft_load_flags" },
170 {"no_hinting", "set no_hinting", 0, AV_OPT_TYPE_CONST, {.i64 = FT_LOAD_NO_HINTING}, INT_MIN, INT_MAX, 0, "ft_load_flags" },
171 {"render", "set render", 0, AV_OPT_TYPE_CONST, {.i64 = FT_LOAD_RENDER}, INT_MIN, INT_MAX, 0, "ft_load_flags" },
172 {"no_bitmap", "set no_bitmap", 0, AV_OPT_TYPE_CONST, {.i64 = FT_LOAD_NO_BITMAP}, INT_MIN, INT_MAX, 0, "ft_load_flags" },
173 {"vertical_layout", "set vertical_layout", 0, AV_OPT_TYPE_CONST, {.i64 = FT_LOAD_VERTICAL_LAYOUT}, INT_MIN, INT_MAX, 0, "ft_load_flags" },
174 {"force_autohint", "set force_autohint", 0, AV_OPT_TYPE_CONST, {.i64 = FT_LOAD_FORCE_AUTOHINT}, INT_MIN, INT_MAX, 0, "ft_load_flags" },
175 {"crop_bitmap", "set crop_bitmap", 0, AV_OPT_TYPE_CONST, {.i64 = FT_LOAD_CROP_BITMAP}, INT_MIN, INT_MAX, 0, "ft_load_flags" },
176 {"pedantic", "set pedantic", 0, AV_OPT_TYPE_CONST, {.i64 = FT_LOAD_PEDANTIC}, INT_MIN, INT_MAX, 0, "ft_load_flags" },
177 {"ignore_global_advance_width", "set ignore_global_advance_width", 0, AV_OPT_TYPE_CONST, {.i64 = FT_LOAD_IGNORE_GLOBAL_ADVANCE_WIDTH}, INT_MIN, INT_MAX, 0, "ft_load_flags" },
178 {"no_recurse", "set no_recurse", 0, AV_OPT_TYPE_CONST, {.i64 = FT_LOAD_NO_RECURSE}, INT_MIN, INT_MAX, 0, "ft_load_flags" },
179 {"ignore_transform", "set ignore_transform", 0, AV_OPT_TYPE_CONST, {.i64 = FT_LOAD_IGNORE_TRANSFORM}, INT_MIN, INT_MAX, 0, "ft_load_flags" },
180 {"monochrome", "set monochrome", 0, AV_OPT_TYPE_CONST, {.i64 = FT_LOAD_MONOCHROME}, INT_MIN, INT_MAX, 0, "ft_load_flags" },
181 {"linear_design", "set linear_design", 0, AV_OPT_TYPE_CONST, {.i64 = FT_LOAD_LINEAR_DESIGN}, INT_MIN, INT_MAX, 0, "ft_load_flags" },
182 {"no_autohint", "set no_autohint", 0, AV_OPT_TYPE_CONST, {.i64 = FT_LOAD_NO_AUTOHINT}, INT_MIN, INT_MAX, 0, "ft_load_flags" },
183 {NULL},
184 };
185 
186 static const char *drawtext_get_name(void *ctx)
187 {
188  return "drawtext";
189 }
190 
191 static const AVClass drawtext_class = {
192  "DrawTextContext",
194  drawtext_options
195 };
196 
197 #undef __FTERRORS_H__
198 #define FT_ERROR_START_LIST {
199 #define FT_ERRORDEF(e, v, s) { (e), (s) },
200 #define FT_ERROR_END_LIST { 0, NULL } };
201 
202 struct ft_error
203 {
204  int err;
205  const char *err_msg;
206 } static ft_errors[] =
207 #include FT_ERRORS_H
208 
209 #define FT_ERRMSG(e) ft_errors[e].err_msg
210 
211 typedef struct {
212  FT_Glyph *glyph;
213  uint32_t code;
214  FT_Bitmap bitmap;
215  FT_BBox bbox;
216  int advance;
217  int bitmap_left;
218  int bitmap_top;
219 } Glyph;
220 
221 static int glyph_cmp(void *key, const void *b)
222 {
223  const Glyph *a = key, *bb = b;
224  int64_t diff = (int64_t)a->code - (int64_t)bb->code;
225  return diff > 0 ? 1 : diff < 0 ? -1 : 0;
226 }
227 
231 static int load_glyph(AVFilterContext *ctx, Glyph **glyph_ptr, uint32_t code)
232 {
233  DrawTextContext *dtext = ctx->priv;
234  Glyph *glyph;
235  struct AVTreeNode *node = NULL;
236  int ret;
237 
238  /* load glyph into dtext->face->glyph */
239  if (FT_Load_Char(dtext->face, code, dtext->ft_load_flags))
240  return AVERROR(EINVAL);
241 
242  /* save glyph */
243  if (!(glyph = av_mallocz(sizeof(*glyph))) ||
244  !(glyph->glyph = av_mallocz(sizeof(*glyph->glyph)))) {
245  ret = AVERROR(ENOMEM);
246  goto error;
247  }
248  glyph->code = code;
249 
250  if (FT_Get_Glyph(dtext->face->glyph, glyph->glyph)) {
251  ret = AVERROR(EINVAL);
252  goto error;
253  }
254 
255  glyph->bitmap = dtext->face->glyph->bitmap;
256  glyph->bitmap_left = dtext->face->glyph->bitmap_left;
257  glyph->bitmap_top = dtext->face->glyph->bitmap_top;
258  glyph->advance = dtext->face->glyph->advance.x >> 6;
259 
260  /* measure text height to calculate text_height (or the maximum text height) */
261  FT_Glyph_Get_CBox(*glyph->glyph, ft_glyph_bbox_pixels, &glyph->bbox);
262 
263  /* cache the newly created glyph */
264  if (!(node = av_tree_node_alloc())) {
265  ret = AVERROR(ENOMEM);
266  goto error;
267  }
268  av_tree_insert(&dtext->glyphs, glyph, glyph_cmp, &node);
269 
270  if (glyph_ptr)
271  *glyph_ptr = glyph;
272  return 0;
273 
274 error:
275  if (glyph)
276  av_freep(&glyph->glyph);
277  av_freep(&glyph);
278  av_freep(&node);
279  return ret;
280 }
281 
282 static av_cold int init(AVFilterContext *ctx, const char *args)
283 {
284  int err;
285  DrawTextContext *dtext = ctx->priv;
286  Glyph *glyph;
287 
288  dtext->class = &drawtext_class;
289  av_opt_set_defaults(dtext);
290  dtext->fontcolor_string = av_strdup("black");
291  dtext->boxcolor_string = av_strdup("white");
292  dtext->shadowcolor_string = av_strdup("black");
293 
294  if ((err = (av_set_options_string(dtext, args, "=", ":"))) < 0) {
295  av_log(ctx, AV_LOG_ERROR, "Error parsing options string: '%s'\n", args);
296  return err;
297  }
298 
299  if (!dtext->fontfile) {
300  av_log(ctx, AV_LOG_ERROR, "No font filename provided\n");
301  return AVERROR(EINVAL);
302  }
303 
304  if (dtext->textfile) {
305  uint8_t *textbuf;
306  size_t textbuf_size;
307 
308  if (dtext->text) {
309  av_log(ctx, AV_LOG_ERROR,
310  "Both text and text file provided. Please provide only one\n");
311  return AVERROR(EINVAL);
312  }
313  if ((err = av_file_map(dtext->textfile, &textbuf, &textbuf_size, 0, ctx)) < 0) {
314  av_log(ctx, AV_LOG_ERROR,
315  "The text file '%s' could not be read or is empty\n",
316  dtext->textfile);
317  return err;
318  }
319 
320  if (!(dtext->text = av_malloc(textbuf_size+1)))
321  return AVERROR(ENOMEM);
322  memcpy(dtext->text, textbuf, textbuf_size);
323  dtext->text[textbuf_size] = 0;
324  av_file_unmap(textbuf, textbuf_size);
325  }
326 
327  if (!dtext->text) {
328  av_log(ctx, AV_LOG_ERROR,
329  "Either text or a valid file must be provided\n");
330  return AVERROR(EINVAL);
331  }
332 
333  if ((err = av_parse_color(dtext->fontcolor_rgba, dtext->fontcolor_string, -1, ctx))) {
334  av_log(ctx, AV_LOG_ERROR,
335  "Invalid font color '%s'\n", dtext->fontcolor_string);
336  return err;
337  }
338 
339  if ((err = av_parse_color(dtext->boxcolor_rgba, dtext->boxcolor_string, -1, ctx))) {
340  av_log(ctx, AV_LOG_ERROR,
341  "Invalid box color '%s'\n", dtext->boxcolor_string);
342  return err;
343  }
344 
345  if ((err = av_parse_color(dtext->shadowcolor_rgba, dtext->shadowcolor_string, -1, ctx))) {
346  av_log(ctx, AV_LOG_ERROR,
347  "Invalid shadow color '%s'\n", dtext->shadowcolor_string);
348  return err;
349  }
350 
351  if ((err = FT_Init_FreeType(&(dtext->library)))) {
352  av_log(ctx, AV_LOG_ERROR,
353  "Could not load FreeType: %s\n", FT_ERRMSG(err));
354  return AVERROR(EINVAL);
355  }
356 
357  /* load the face, and set up the encoding, which is by default UTF-8 */
358  if ((err = FT_New_Face(dtext->library, dtext->fontfile, 0, &dtext->face))) {
359  av_log(ctx, AV_LOG_ERROR, "Could not load fontface from file '%s': %s\n",
360  dtext->fontfile, FT_ERRMSG(err));
361  return AVERROR(EINVAL);
362  }
363  if ((err = FT_Set_Pixel_Sizes(dtext->face, 0, dtext->fontsize))) {
364  av_log(ctx, AV_LOG_ERROR, "Could not set font size to %d pixels: %s\n",
365  dtext->fontsize, FT_ERRMSG(err));
366  return AVERROR(EINVAL);
367  }
368 
369  dtext->use_kerning = FT_HAS_KERNING(dtext->face);
370 
371  /* load the fallback glyph with code 0 */
372  load_glyph(ctx, NULL, 0);
373 
374  /* set the tabsize in pixels */
375  if ((err = load_glyph(ctx, &glyph, ' ') < 0)) {
376  av_log(ctx, AV_LOG_ERROR, "Could not set tabsize.\n");
377  return err;
378  }
379  dtext->tabsize *= glyph->advance;
380 
381 #if !HAVE_LOCALTIME_R
382  av_log(ctx, AV_LOG_WARNING, "strftime() expansion unavailable!\n");
383 #endif
384 
385  return 0;
386 }
387 
389 {
390  static const enum AVPixelFormat pix_fmts[] = {
398  };
399 
401  return 0;
402 }
403 
404 static int glyph_enu_free(void *opaque, void *elem)
405 {
406  av_free(elem);
407  return 0;
408 }
409 
410 static av_cold void uninit(AVFilterContext *ctx)
411 {
412  DrawTextContext *dtext = ctx->priv;
413  int i;
414 
415  av_freep(&dtext->fontfile);
416  av_freep(&dtext->text);
417  av_freep(&dtext->expanded_text);
418  av_freep(&dtext->fontcolor_string);
419  av_freep(&dtext->boxcolor_string);
420  av_freep(&dtext->positions);
421  av_freep(&dtext->shadowcolor_string);
423  av_tree_destroy(dtext->glyphs);
424  dtext->glyphs = 0;
425  FT_Done_Face(dtext->face);
426  FT_Done_FreeType(dtext->library);
427 
428  for (i = 0; i < 4; i++) {
429  av_freep(&dtext->box_line[i]);
430  dtext->pixel_step[i] = 0;
431  }
432 
433 }
434 
435 static inline int is_newline(uint32_t c)
436 {
437  return c == '\n' || c == '\r' || c == '\f' || c == '\v';
438 }
439 
441 {
442  DrawTextContext *dtext = ctx->priv;
443  uint32_t code = 0, prev_code = 0;
444  int x = 0, y = 0, i = 0, ret;
445  int text_height, baseline;
446  char *text = dtext->text;
447  uint8_t *p;
448  int str_w = 0, len;
449  int y_min = 32000, y_max = -32000;
450  FT_Vector delta;
451  Glyph *glyph = NULL, *prev_glyph = NULL;
452  Glyph dummy = { 0 };
453  int width = ctx->inputs[0]->w;
454  int height = ctx->inputs[0]->h;
455 
456 #if HAVE_LOCALTIME_R
457  time_t now = time(0);
458  struct tm ltime;
459  uint8_t *buf = dtext->expanded_text;
460  int buf_size = dtext->expanded_text_size;
461 
462  if (!buf)
463  buf_size = 2*strlen(dtext->text)+1;
464 
465  localtime_r(&now, &ltime);
466 
467  while ((buf = av_realloc(buf, buf_size))) {
468  *buf = 1;
469  if (strftime(buf, buf_size, dtext->text, &ltime) != 0 || *buf == 0)
470  break;
471  buf_size *= 2;
472  }
473 
474  if (!buf)
475  return AVERROR(ENOMEM);
476  text = dtext->expanded_text = buf;
477  dtext->expanded_text_size = buf_size;
478 #endif
479 
480  if ((len = strlen(text)) > dtext->nb_positions) {
481  FT_Vector *p = av_realloc(dtext->positions,
482  len * sizeof(*dtext->positions));
483  if (!p) {
484  av_freep(dtext->positions);
485  dtext->nb_positions = 0;
486  return AVERROR(ENOMEM);
487  } else {
488  dtext->positions = p;
489  dtext->nb_positions = len;
490  }
491  }
492 
493  /* load and cache glyphs */
494  for (i = 0, p = text; *p; i++) {
495  GET_UTF8(code, *p++, continue;);
496 
497  /* get glyph */
498  dummy.code = code;
499  glyph = av_tree_find(dtext->glyphs, &dummy, glyph_cmp, NULL);
500  if (!glyph) {
501  ret = load_glyph(ctx, &glyph, code);
502  if (ret)
503  return ret;
504  }
505 
506  y_min = FFMIN(glyph->bbox.yMin, y_min);
507  y_max = FFMAX(glyph->bbox.yMax, y_max);
508  }
509  text_height = y_max - y_min;
510  baseline = y_max;
511 
512  /* compute and save position for each glyph */
513  glyph = NULL;
514  for (i = 0, p = text; *p; i++) {
515  GET_UTF8(code, *p++, continue;);
516 
517  /* skip the \n in the sequence \r\n */
518  if (prev_code == '\r' && code == '\n')
519  continue;
520 
521  prev_code = code;
522  if (is_newline(code)) {
523  str_w = FFMAX(str_w, x - dtext->x);
524  y += text_height;
525  x = 0;
526  continue;
527  }
528 
529  /* get glyph */
530  prev_glyph = glyph;
531  dummy.code = code;
532  glyph = av_tree_find(dtext->glyphs, &dummy, glyph_cmp, NULL);
533 
534  /* kerning */
535  if (dtext->use_kerning && prev_glyph && glyph->code) {
536  FT_Get_Kerning(dtext->face, prev_glyph->code, glyph->code,
537  ft_kerning_default, &delta);
538  x += delta.x >> 6;
539  }
540 
541  if (x + glyph->bbox.xMax >= width) {
542  str_w = FFMAX(str_w, x);
543  y += text_height;
544  x = 0;
545  }
546 
547  /* save position */
548  dtext->positions[i].x = x + glyph->bitmap_left;
549  dtext->positions[i].y = y - glyph->bitmap_top + baseline;
550  if (code == '\t') x = (x / dtext->tabsize + 1)*dtext->tabsize;
551  else x += glyph->advance;
552  }
553 
554  str_w = FFMIN(width - 1, FFMAX(str_w, x));
555  y = FFMIN(y + text_height, height - 1);
556 
557  dtext->w = str_w;
558  dtext->var_values[VAR_TEXT_W] = dtext->var_values[VAR_TW] = dtext->w;
559  dtext->h = y;
560  dtext->var_values[VAR_TEXT_H] = dtext->var_values[VAR_TH] = dtext->h;
561 
562  return 0;
563 }
564 
565 
566 static int config_input(AVFilterLink *inlink)
567 {
568  AVFilterContext *ctx = inlink->dst;
569  DrawTextContext *dtext = ctx->priv;
570  const AVPixFmtDescriptor *pix_desc = av_pix_fmt_desc_get(inlink->format);
571  int ret;
572 
573  dtext->hsub = pix_desc->log2_chroma_w;
574  dtext->vsub = pix_desc->log2_chroma_h;
575 
576  dtext->var_values[VAR_E ] = M_E;
577  dtext->var_values[VAR_PHI] = M_PHI;
578  dtext->var_values[VAR_PI ] = M_PI;
579 
580  dtext->var_values[VAR_MAIN_W] =
581  dtext->var_values[VAR_MW] = ctx->inputs[0]->w;
582  dtext->var_values[VAR_MAIN_H] =
583  dtext->var_values[VAR_MH] = ctx->inputs[0]->h;
584 
585  dtext->var_values[VAR_X] = 0;
586  dtext->var_values[VAR_Y] = 0;
587  dtext->var_values[VAR_N] = 0;
588  dtext->var_values[VAR_T] = NAN;
589 
590  av_lfg_init(&dtext->prng, av_get_random_seed());
591 
592  if ((ret = av_expr_parse(&dtext->x_pexpr, dtext->x_expr, var_names,
593  NULL, NULL, fun2_names, fun2, 0, ctx)) < 0 ||
594  (ret = av_expr_parse(&dtext->y_pexpr, dtext->y_expr, var_names,
595  NULL, NULL, fun2_names, fun2, 0, ctx)) < 0 ||
596  (ret = av_expr_parse(&dtext->d_pexpr, dtext->d_expr, var_names,
597  NULL, NULL, fun2_names, fun2, 0, ctx)) < 0)
598  return AVERROR(EINVAL);
599 
600  if ((ret =
602  inlink->w, dtext->boxcolor,
603  inlink->format, dtext->boxcolor_rgba,
604  &dtext->is_packed_rgb, dtext->rgba_map)) < 0)
605  return ret;
606 
607  if (!dtext->is_packed_rgb) {
608  uint8_t *rgba = dtext->fontcolor_rgba;
609  dtext->fontcolor[0] = RGB_TO_Y_CCIR(rgba[0], rgba[1], rgba[2]);
610  dtext->fontcolor[1] = RGB_TO_U_CCIR(rgba[0], rgba[1], rgba[2], 0);
611  dtext->fontcolor[2] = RGB_TO_V_CCIR(rgba[0], rgba[1], rgba[2], 0);
612  dtext->fontcolor[3] = rgba[3];
613  rgba = dtext->shadowcolor_rgba;
614  dtext->shadowcolor[0] = RGB_TO_Y_CCIR(rgba[0], rgba[1], rgba[2]);
615  dtext->shadowcolor[1] = RGB_TO_U_CCIR(rgba[0], rgba[1], rgba[2], 0);
616  dtext->shadowcolor[2] = RGB_TO_V_CCIR(rgba[0], rgba[1], rgba[2], 0);
617  dtext->shadowcolor[3] = rgba[3];
618  }
619 
620  dtext->draw = 1;
621 
622  return dtext_prepare_text(ctx);
623 }
624 
625 #define GET_BITMAP_VAL(r, c) \
626  bitmap->pixel_mode == FT_PIXEL_MODE_MONO ? \
627  (bitmap->buffer[(r) * bitmap->pitch + ((c)>>3)] & (0x80 >> ((c)&7))) * 255 : \
628  bitmap->buffer[(r) * bitmap->pitch + (c)]
629 
630 #define SET_PIXEL_YUV(picref, yuva_color, val, x, y, hsub, vsub) { \
631  luma_pos = ((x) ) + ((y) ) * picref->linesize[0]; \
632  alpha = yuva_color[3] * (val) * 129; \
633  picref->data[0][luma_pos] = (alpha * yuva_color[0] + (255*255*129 - alpha) * picref->data[0][luma_pos] ) >> 23; \
634  if (((x) & ((1<<(hsub)) - 1)) == 0 && ((y) & ((1<<(vsub)) - 1)) == 0) {\
635  chroma_pos1 = ((x) >> (hsub)) + ((y) >> (vsub)) * picref->linesize[1]; \
636  chroma_pos2 = ((x) >> (hsub)) + ((y) >> (vsub)) * picref->linesize[2]; \
637  picref->data[1][chroma_pos1] = (alpha * yuva_color[1] + (255*255*129 - alpha) * picref->data[1][chroma_pos1]) >> 23; \
638  picref->data[2][chroma_pos2] = (alpha * yuva_color[2] + (255*255*129 - alpha) * picref->data[2][chroma_pos2]) >> 23; \
639  }\
640 }
641 
642 static inline int draw_glyph_yuv(AVFilterBufferRef *picref, FT_Bitmap *bitmap, unsigned int x,
643  unsigned int y, unsigned int width, unsigned int height,
644  const uint8_t yuva_color[4], int hsub, int vsub)
645 {
646  int r, c, alpha;
647  unsigned int luma_pos, chroma_pos1, chroma_pos2;
648  uint8_t src_val;
649 
650  for (r = 0; r < bitmap->rows && r+y < height; r++) {
651  for (c = 0; c < bitmap->width && c+x < width; c++) {
652  /* get intensity value in the glyph bitmap (source) */
653  src_val = GET_BITMAP_VAL(r, c);
654  if (!src_val)
655  continue;
656 
657  SET_PIXEL_YUV(picref, yuva_color, src_val, c+x, y+r, hsub, vsub);
658  }
659  }
660 
661  return 0;
662 }
663 
664 #define SET_PIXEL_RGB(picref, rgba_color, val, x, y, pixel_step, r_off, g_off, b_off, a_off) { \
665  p = picref->data[0] + (x) * pixel_step + ((y) * picref->linesize[0]); \
666  alpha = rgba_color[3] * (val) * 129; \
667  *(p+r_off) = (alpha * rgba_color[0] + (255*255*129 - alpha) * *(p+r_off)) >> 23; \
668  *(p+g_off) = (alpha * rgba_color[1] + (255*255*129 - alpha) * *(p+g_off)) >> 23; \
669  *(p+b_off) = (alpha * rgba_color[2] + (255*255*129 - alpha) * *(p+b_off)) >> 23; \
670 }
671 
672 static inline int draw_glyph_rgb(AVFilterBufferRef *picref, FT_Bitmap *bitmap,
673  unsigned int x, unsigned int y,
674  unsigned int width, unsigned int height, int pixel_step,
675  const uint8_t rgba_color[4], const uint8_t rgba_map[4])
676 {
677  int r, c, alpha;
678  uint8_t *p;
679  uint8_t src_val;
680 
681  for (r = 0; r < bitmap->rows && r+y < height; r++) {
682  for (c = 0; c < bitmap->width && c+x < width; c++) {
683  /* get intensity value in the glyph bitmap (source) */
684  src_val = GET_BITMAP_VAL(r, c);
685  if (!src_val)
686  continue;
687 
688  SET_PIXEL_RGB(picref, rgba_color, src_val, c+x, y+r, pixel_step,
689  rgba_map[0], rgba_map[1], rgba_map[2], rgba_map[3]);
690  }
691  }
692 
693  return 0;
694 }
695 
696 static inline void drawbox(AVFilterBufferRef *picref, unsigned int x, unsigned int y,
697  unsigned int width, unsigned int height,
698  uint8_t *line[4], int pixel_step[4], uint8_t color[4],
699  int hsub, int vsub, int is_rgba_packed, uint8_t rgba_map[4])
700 {
701  int i, j, alpha;
702 
703  if (color[3] != 0xFF) {
704  if (is_rgba_packed) {
705  uint8_t *p;
706  for (j = 0; j < height; j++)
707  for (i = 0; i < width; i++)
708  SET_PIXEL_RGB(picref, color, 255, i+x, y+j, pixel_step[0],
709  rgba_map[0], rgba_map[1], rgba_map[2], rgba_map[3]);
710  } else {
711  unsigned int luma_pos, chroma_pos1, chroma_pos2;
712  for (j = 0; j < height; j++)
713  for (i = 0; i < width; i++)
714  SET_PIXEL_YUV(picref, color, 255, i+x, y+j, hsub, vsub);
715  }
716  } else {
717  ff_draw_rectangle(picref->data, picref->linesize,
718  line, pixel_step, hsub, vsub,
719  x, y, width, height);
720  }
721 }
722 
723 static int draw_glyphs(DrawTextContext *dtext, AVFilterBufferRef *picref,
724  int width, int height, const uint8_t rgbcolor[4], const uint8_t yuvcolor[4], int x, int y)
725 {
726  char *text = HAVE_LOCALTIME_R ? dtext->expanded_text : dtext->text;
727  uint32_t code = 0;
728  int i;
729  uint8_t *p;
730  Glyph *glyph = NULL;
731 
732  for (i = 0, p = text; *p; i++) {
733  Glyph dummy = { 0 };
734  GET_UTF8(code, *p++, continue;);
735 
736  /* skip new line chars, just go to new line */
737  if (code == '\n' || code == '\r' || code == '\t')
738  continue;
739 
740  dummy.code = code;
741  glyph = av_tree_find(dtext->glyphs, &dummy, (void *)glyph_cmp, NULL);
742 
743  if (glyph->bitmap.pixel_mode != FT_PIXEL_MODE_MONO &&
744  glyph->bitmap.pixel_mode != FT_PIXEL_MODE_GRAY)
745  return AVERROR(EINVAL);
746 
747  if (dtext->is_packed_rgb) {
748  draw_glyph_rgb(picref, &glyph->bitmap,
749  dtext->positions[i].x+x, dtext->positions[i].y+y, width, height,
750  dtext->pixel_step[0], rgbcolor, dtext->rgba_map);
751  } else {
752  draw_glyph_yuv(picref, &glyph->bitmap,
753  dtext->positions[i].x+x, dtext->positions[i].y+y, width, height,
754  yuvcolor, dtext->hsub, dtext->vsub);
755  }
756  }
757 
758  return 0;
759 }
760 
761 static int draw_text(AVFilterContext *ctx, AVFilterBufferRef *picref,
762  int width, int height)
763 {
764  DrawTextContext *dtext = ctx->priv;
765  int ret;
766 
767  /* draw box */
768  if (dtext->draw_box)
769  drawbox(picref, dtext->x, dtext->y, dtext->w, dtext->h,
770  dtext->box_line, dtext->pixel_step, dtext->boxcolor,
771  dtext->hsub, dtext->vsub, dtext->is_packed_rgb,
772  dtext->rgba_map);
773 
774  if (dtext->shadowx || dtext->shadowy) {
775  if ((ret = draw_glyphs(dtext, picref, width, height,
776  dtext->shadowcolor_rgba,
777  dtext->shadowcolor,
778  dtext->x + dtext->shadowx,
779  dtext->y + dtext->shadowy)) < 0)
780  return ret;
781  }
782 
783  if ((ret = draw_glyphs(dtext, picref, width, height,
784  dtext->fontcolor_rgba,
785  dtext->fontcolor,
786  dtext->x,
787  dtext->y)) < 0)
788  return ret;
789 
790  return 0;
791 }
792 
793 static inline int normalize_double(int *n, double d)
794 {
795  int ret = 0;
796 
797  if (isnan(d)) {
798  ret = AVERROR(EINVAL);
799  } else if (d > INT_MAX || d < INT_MIN) {
800  *n = d > INT_MAX ? INT_MAX : INT_MIN;
801  ret = AVERROR(EINVAL);
802  } else
803  *n = round(d);
804 
805  return ret;
806 }
807 
808 static int filter_frame(AVFilterLink *inlink, AVFilterBufferRef *frame)
809 {
810  AVFilterContext *ctx = inlink->dst;
811  DrawTextContext *dtext = ctx->priv;
812  int ret = 0;
813 
814  if ((ret = dtext_prepare_text(ctx)) < 0) {
815  av_log(ctx, AV_LOG_ERROR, "Can't draw text\n");
816  avfilter_unref_bufferp(&frame);
817  return ret;
818  }
819 
820  dtext->var_values[VAR_T] = frame->pts == AV_NOPTS_VALUE ?
821  NAN : frame->pts * av_q2d(inlink->time_base);
822  dtext->var_values[VAR_X] =
823  av_expr_eval(dtext->x_pexpr, dtext->var_values, &dtext->prng);
824  dtext->var_values[VAR_Y] =
825  av_expr_eval(dtext->y_pexpr, dtext->var_values, &dtext->prng);
826  dtext->var_values[VAR_X] =
827  av_expr_eval(dtext->x_pexpr, dtext->var_values, &dtext->prng);
828 
829  dtext->draw = av_expr_eval(dtext->d_pexpr, dtext->var_values, &dtext->prng);
830 
831  normalize_double(&dtext->x, dtext->var_values[VAR_X]);
832  normalize_double(&dtext->y, dtext->var_values[VAR_Y]);
833 
834  if (dtext->fix_bounds) {
835  if (dtext->x < 0) dtext->x = 0;
836  if (dtext->y < 0) dtext->y = 0;
837  if ((unsigned)dtext->x + (unsigned)dtext->w > inlink->w)
838  dtext->x = inlink->w - dtext->w;
839  if ((unsigned)dtext->y + (unsigned)dtext->h > inlink->h)
840  dtext->y = inlink->h - dtext->h;
841  }
842 
843  dtext->x &= ~((1 << dtext->hsub) - 1);
844  dtext->y &= ~((1 << dtext->vsub) - 1);
845 
846  av_dlog(ctx, "n:%d t:%f x:%d y:%d x+w:%d y+h:%d\n",
847  (int)dtext->var_values[VAR_N], dtext->var_values[VAR_T],
848  dtext->x, dtext->y, dtext->x+dtext->w, dtext->y+dtext->h);
849 
850  if (dtext->draw)
851  draw_text(inlink->dst, frame, frame->video->w, frame->video->h);
852 
853  dtext->var_values[VAR_N] += 1.0;
854 
855  return ff_filter_frame(inlink->dst->outputs[0], frame);
856 }
857 
859  {
860  .name = "default",
861  .type = AVMEDIA_TYPE_VIDEO,
862  .get_video_buffer = ff_null_get_video_buffer,
863  .filter_frame = filter_frame,
864  .config_props = config_input,
865  .min_perms = AV_PERM_WRITE |
866  AV_PERM_READ,
867  .rej_perms = AV_PERM_PRESERVE
868  },
869  { NULL }
870 };
871 
873  {
874  .name = "default",
875  .type = AVMEDIA_TYPE_VIDEO,
876  },
877  { NULL }
878 };
879 
881  .name = "drawtext",
882  .description = NULL_IF_CONFIG_SMALL("Draw text on top of video frames using libfreetype library."),
883  .priv_size = sizeof(DrawTextContext),
884  .init = init,
885  .uninit = uninit,
887 
888  .inputs = avfilter_vf_drawtext_inputs,
889  .outputs = avfilter_vf_drawtext_outputs,
890 };