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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 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  * drawtext filter, based on the original vhook/drawtext.c
26  * filter by Gustavo Sverzut Barbieri
27  */
28 
29 #include "config.h"
30 
31 #if HAVE_SYS_TIME_H
32 #include <sys/time.h>
33 #endif
34 #include <sys/types.h>
35 #include <sys/stat.h>
36 #include <time.h>
37 #if HAVE_UNISTD_H
38 #include <unistd.h>
39 #endif
40 #include <fenv.h>
41 
42 #if CONFIG_LIBFONTCONFIG
43 #include <fontconfig/fontconfig.h>
44 #endif
45 
46 #include "libavutil/avstring.h"
47 #include "libavutil/bprint.h"
48 #include "libavutil/common.h"
49 #include "libavutil/file.h"
50 #include "libavutil/eval.h"
51 #include "libavutil/opt.h"
52 #include "libavutil/random_seed.h"
53 #include "libavutil/parseutils.h"
54 #include "libavutil/timecode.h"
56 #include "libavutil/tree.h"
57 #include "libavutil/lfg.h"
58 #include "avfilter.h"
59 #include "drawutils.h"
60 #include "formats.h"
61 #include "internal.h"
62 #include "video.h"
63 
64 #if CONFIG_LIBFRIBIDI
65 #include <fribidi.h>
66 #endif
67 
68 #include <ft2build.h>
69 #include FT_FREETYPE_H
70 #include FT_GLYPH_H
71 #include FT_STROKER_H
72 
73 static const char *const var_names[] = {
74  "dar",
75  "hsub", "vsub",
76  "line_h", "lh", ///< line height, same as max_glyph_h
77  "main_h", "h", "H", ///< height of the input video
78  "main_w", "w", "W", ///< width of the input video
79  "max_glyph_a", "ascent", ///< max glyph ascent
80  "max_glyph_d", "descent", ///< min glyph descent
81  "max_glyph_h", ///< max glyph height
82  "max_glyph_w", ///< max glyph width
83  "n", ///< number of frame
84  "sar",
85  "t", ///< timestamp expressed in seconds
86  "text_h", "th", ///< height of the rendered text
87  "text_w", "tw", ///< width of the rendered text
88  "x",
89  "y",
90  "pict_type",
91  NULL
92 };
93 
94 static const char *const fun2_names[] = {
95  "rand"
96 };
97 
98 static double drand(void *opaque, double min, double max)
99 {
100  return min + (max-min) / UINT_MAX * av_lfg_get(opaque);
101 }
102 
103 typedef double (*eval_func2)(void *, double a, double b);
104 
105 static const eval_func2 fun2[] = {
106  drand,
107  NULL
108 };
109 
110 enum var_name {
129 };
130 
135 };
136 
137 typedef struct DrawTextContext {
138  const AVClass *class;
139  int exp_mode; ///< expansion mode to use for the text
140  int reinit; ///< tells if the filter is being reinited
141 #if CONFIG_LIBFONTCONFIG
142  uint8_t *font; ///< font to be used
143 #endif
144  uint8_t *fontfile; ///< font to be used
145  uint8_t *text; ///< text to be drawn
146  AVBPrint expanded_text; ///< used to contain the expanded text
147  uint8_t *fontcolor_expr; ///< fontcolor expression to evaluate
148  AVBPrint expanded_fontcolor; ///< used to contain the expanded fontcolor spec
149  int ft_load_flags; ///< flags used for loading fonts, see FT_LOAD_*
150  FT_Vector *positions; ///< positions for each element in the text
151  size_t nb_positions; ///< number of elements of positions array
152  char *textfile; ///< file with text to be drawn
153  int x; ///< x position to start drawing text
154  int y; ///< y position to start drawing text
155  int max_glyph_w; ///< max glyph width
156  int max_glyph_h; ///< max glyph height
158  int borderw; ///< border width
159  unsigned int fontsize; ///< font size to use
160 
161  short int draw_box; ///< draw box around text - true or false
162  int boxborderw; ///< box border width
163  int use_kerning; ///< font kerning is used - true/false
164  int tabsize; ///< tab size
165  int fix_bounds; ///< do we let it go out of frame bounds - t/f
166 
168  FFDrawColor fontcolor; ///< foreground color
169  FFDrawColor shadowcolor; ///< shadow color
170  FFDrawColor bordercolor; ///< border color
171  FFDrawColor boxcolor; ///< background color
172 
173  FT_Library library; ///< freetype font library handle
174  FT_Face face; ///< freetype font face handle
175  FT_Stroker stroker; ///< freetype stroker handle
176  struct AVTreeNode *glyphs; ///< rendered glyphs, stored using the UTF-32 char code
177  char *x_expr; ///< expression for x position
178  char *y_expr; ///< expression for y position
179  AVExpr *x_pexpr, *y_pexpr; ///< parsed expressions for x and y
180  int64_t basetime; ///< base pts time in the real world for display
182  char *a_expr;
184  int alpha;
185  AVLFG prng; ///< random
186  char *tc_opt_string; ///< specified timecode option string
187  AVRational tc_rate; ///< frame rate for timecode
188  AVTimecode tc; ///< timecode context
189  int tc24hmax; ///< 1 if timecode is wrapped to 24 hours, 0 otherwise
190  int reload; ///< reload text file for each frame
191  int start_number; ///< starting frame number for n/frame_num var
192 #if CONFIG_LIBFRIBIDI
193  int text_shaping; ///< 1 to shape the text before drawing it
194 #endif
197 
198 #define OFFSET(x) offsetof(DrawTextContext, x)
199 #define FLAGS AV_OPT_FLAG_FILTERING_PARAM|AV_OPT_FLAG_VIDEO_PARAM
200 
201 static const AVOption drawtext_options[]= {
202  {"fontfile", "set font file", OFFSET(fontfile), AV_OPT_TYPE_STRING, {.str=NULL}, CHAR_MIN, CHAR_MAX, FLAGS},
203  {"text", "set text", OFFSET(text), AV_OPT_TYPE_STRING, {.str=NULL}, CHAR_MIN, CHAR_MAX, FLAGS},
204  {"textfile", "set text file", OFFSET(textfile), AV_OPT_TYPE_STRING, {.str=NULL}, CHAR_MIN, CHAR_MAX, FLAGS},
205  {"fontcolor", "set foreground color", OFFSET(fontcolor.rgba), AV_OPT_TYPE_COLOR, {.str="black"}, CHAR_MIN, CHAR_MAX, FLAGS},
206  {"fontcolor_expr", "set foreground color expression", OFFSET(fontcolor_expr), AV_OPT_TYPE_STRING, {.str=""}, CHAR_MIN, CHAR_MAX, FLAGS},
207  {"boxcolor", "set box color", OFFSET(boxcolor.rgba), AV_OPT_TYPE_COLOR, {.str="white"}, CHAR_MIN, CHAR_MAX, FLAGS},
208  {"bordercolor", "set border color", OFFSET(bordercolor.rgba), AV_OPT_TYPE_COLOR, {.str="black"}, CHAR_MIN, CHAR_MAX, FLAGS},
209  {"shadowcolor", "set shadow color", OFFSET(shadowcolor.rgba), AV_OPT_TYPE_COLOR, {.str="black"}, CHAR_MIN, CHAR_MAX, FLAGS},
210  {"box", "set box", OFFSET(draw_box), AV_OPT_TYPE_INT, {.i64=0}, 0, 1 , FLAGS},
211  {"boxborderw", "set box border width", OFFSET(boxborderw), AV_OPT_TYPE_INT, {.i64=0}, INT_MIN, INT_MAX , FLAGS},
212  {"fontsize", "set font size", OFFSET(fontsize), AV_OPT_TYPE_INT, {.i64=0}, 0, INT_MAX , FLAGS},
213  {"x", "set x expression", OFFSET(x_expr), AV_OPT_TYPE_STRING, {.str="0"}, CHAR_MIN, CHAR_MAX, FLAGS},
214  {"y", "set y expression", OFFSET(y_expr), AV_OPT_TYPE_STRING, {.str="0"}, CHAR_MIN, CHAR_MAX, FLAGS},
215  {"shadowx", "set x", OFFSET(shadowx), AV_OPT_TYPE_INT, {.i64=0}, INT_MIN, INT_MAX , FLAGS},
216  {"shadowy", "set y", OFFSET(shadowy), AV_OPT_TYPE_INT, {.i64=0}, INT_MIN, INT_MAX , FLAGS},
217  {"borderw", "set border width", OFFSET(borderw), AV_OPT_TYPE_INT, {.i64=0}, INT_MIN, INT_MAX , FLAGS},
218  {"tabsize", "set tab size", OFFSET(tabsize), AV_OPT_TYPE_INT, {.i64=4}, 0, INT_MAX , FLAGS},
219  {"basetime", "set base time", OFFSET(basetime), AV_OPT_TYPE_INT64, {.i64=AV_NOPTS_VALUE}, INT64_MIN, INT64_MAX , FLAGS},
220 #if CONFIG_LIBFONTCONFIG
221  { "font", "Font name", OFFSET(font), AV_OPT_TYPE_STRING, { .str = "Sans" }, .flags = FLAGS },
222 #endif
223 
224  {"expansion", "set the expansion mode", OFFSET(exp_mode), AV_OPT_TYPE_INT, {.i64=EXP_NORMAL}, 0, 2, FLAGS, "expansion"},
225  {"none", "set no expansion", OFFSET(exp_mode), AV_OPT_TYPE_CONST, {.i64=EXP_NONE}, 0, 0, FLAGS, "expansion"},
226  {"normal", "set normal expansion", OFFSET(exp_mode), AV_OPT_TYPE_CONST, {.i64=EXP_NORMAL}, 0, 0, FLAGS, "expansion"},
227  {"strftime", "set strftime expansion (deprecated)", OFFSET(exp_mode), AV_OPT_TYPE_CONST, {.i64=EXP_STRFTIME}, 0, 0, FLAGS, "expansion"},
228 
229  {"timecode", "set initial timecode", OFFSET(tc_opt_string), AV_OPT_TYPE_STRING, {.str=NULL}, CHAR_MIN, CHAR_MAX, FLAGS},
230  {"tc24hmax", "set 24 hours max (timecode only)", OFFSET(tc24hmax), AV_OPT_TYPE_INT, {.i64=0}, 0, 1, FLAGS},
231  {"timecode_rate", "set rate (timecode only)", OFFSET(tc_rate), AV_OPT_TYPE_RATIONAL, {.dbl=0}, 0, INT_MAX, FLAGS},
232  {"r", "set rate (timecode only)", OFFSET(tc_rate), AV_OPT_TYPE_RATIONAL, {.dbl=0}, 0, INT_MAX, FLAGS},
233  {"rate", "set rate (timecode only)", OFFSET(tc_rate), AV_OPT_TYPE_RATIONAL, {.dbl=0}, 0, INT_MAX, FLAGS},
234  {"reload", "reload text file for each frame", OFFSET(reload), AV_OPT_TYPE_INT, {.i64=0}, 0, 1, FLAGS},
235  { "alpha", "apply alpha while rendering", OFFSET(a_expr), AV_OPT_TYPE_STRING, { .str = "1" }, .flags = FLAGS },
236  {"fix_bounds", "if true, check and fix text coords to avoid clipping", OFFSET(fix_bounds), AV_OPT_TYPE_INT, {.i64=1}, 0, 1, FLAGS},
237  {"start_number", "start frame number for n/frame_num variable", OFFSET(start_number), AV_OPT_TYPE_INT, {.i64=0}, 0, INT_MAX, FLAGS},
238 
239 #if CONFIG_LIBFRIBIDI
240  {"text_shaping", "attempt to shape text before drawing", OFFSET(text_shaping), AV_OPT_TYPE_INT, {.i64=1}, 0, 1, FLAGS},
241 #endif
242 
243  /* FT_LOAD_* flags */
244  { "ft_load_flags", "set font loading flags for libfreetype", OFFSET(ft_load_flags), AV_OPT_TYPE_FLAGS, { .i64 = FT_LOAD_DEFAULT }, 0, INT_MAX, FLAGS, "ft_load_flags" },
245  { "default", NULL, 0, AV_OPT_TYPE_CONST, { .i64 = FT_LOAD_DEFAULT }, .flags = FLAGS, .unit = "ft_load_flags" },
246  { "no_scale", NULL, 0, AV_OPT_TYPE_CONST, { .i64 = FT_LOAD_NO_SCALE }, .flags = FLAGS, .unit = "ft_load_flags" },
247  { "no_hinting", NULL, 0, AV_OPT_TYPE_CONST, { .i64 = FT_LOAD_NO_HINTING }, .flags = FLAGS, .unit = "ft_load_flags" },
248  { "render", NULL, 0, AV_OPT_TYPE_CONST, { .i64 = FT_LOAD_RENDER }, .flags = FLAGS, .unit = "ft_load_flags" },
249  { "no_bitmap", NULL, 0, AV_OPT_TYPE_CONST, { .i64 = FT_LOAD_NO_BITMAP }, .flags = FLAGS, .unit = "ft_load_flags" },
250  { "vertical_layout", NULL, 0, AV_OPT_TYPE_CONST, { .i64 = FT_LOAD_VERTICAL_LAYOUT }, .flags = FLAGS, .unit = "ft_load_flags" },
251  { "force_autohint", NULL, 0, AV_OPT_TYPE_CONST, { .i64 = FT_LOAD_FORCE_AUTOHINT }, .flags = FLAGS, .unit = "ft_load_flags" },
252  { "crop_bitmap", NULL, 0, AV_OPT_TYPE_CONST, { .i64 = FT_LOAD_CROP_BITMAP }, .flags = FLAGS, .unit = "ft_load_flags" },
253  { "pedantic", NULL, 0, AV_OPT_TYPE_CONST, { .i64 = FT_LOAD_PEDANTIC }, .flags = FLAGS, .unit = "ft_load_flags" },
254  { "ignore_global_advance_width", NULL, 0, AV_OPT_TYPE_CONST, { .i64 = FT_LOAD_IGNORE_GLOBAL_ADVANCE_WIDTH }, .flags = FLAGS, .unit = "ft_load_flags" },
255  { "no_recurse", NULL, 0, AV_OPT_TYPE_CONST, { .i64 = FT_LOAD_NO_RECURSE }, .flags = FLAGS, .unit = "ft_load_flags" },
256  { "ignore_transform", NULL, 0, AV_OPT_TYPE_CONST, { .i64 = FT_LOAD_IGNORE_TRANSFORM }, .flags = FLAGS, .unit = "ft_load_flags" },
257  { "monochrome", NULL, 0, AV_OPT_TYPE_CONST, { .i64 = FT_LOAD_MONOCHROME }, .flags = FLAGS, .unit = "ft_load_flags" },
258  { "linear_design", NULL, 0, AV_OPT_TYPE_CONST, { .i64 = FT_LOAD_LINEAR_DESIGN }, .flags = FLAGS, .unit = "ft_load_flags" },
259  { "no_autohint", NULL, 0, AV_OPT_TYPE_CONST, { .i64 = FT_LOAD_NO_AUTOHINT }, .flags = FLAGS, .unit = "ft_load_flags" },
260  { NULL }
261 };
262 
264 
265 #undef __FTERRORS_H__
266 #define FT_ERROR_START_LIST {
267 #define FT_ERRORDEF(e, v, s) { (e), (s) },
268 #define FT_ERROR_END_LIST { 0, NULL } };
269 
270 static const struct ft_error
271 {
272  int err;
273  const char *err_msg;
274 } ft_errors[] =
275 #include FT_ERRORS_H
276 
277 #define FT_ERRMSG(e) ft_errors[e].err_msg
278 
279 typedef struct Glyph {
280  FT_Glyph glyph;
281  FT_Glyph border_glyph;
282  uint32_t code;
283  FT_Bitmap bitmap; ///< array holding bitmaps of font
284  FT_Bitmap border_bitmap; ///< array holding bitmaps of font border
285  FT_BBox bbox;
286  int advance;
287  int bitmap_left;
288  int bitmap_top;
289 } Glyph;
290 
291 static int glyph_cmp(void *key, const void *b)
292 {
293  const Glyph *a = key, *bb = b;
294  int64_t diff = (int64_t)a->code - (int64_t)bb->code;
295  return diff > 0 ? 1 : diff < 0 ? -1 : 0;
296 }
297 
298 /**
299  * Load glyphs corresponding to the UTF-32 codepoint code.
300  */
301 static int load_glyph(AVFilterContext *ctx, Glyph **glyph_ptr, uint32_t code)
302 {
303  DrawTextContext *s = ctx->priv;
304  FT_BitmapGlyph bitmapglyph;
305  Glyph *glyph;
306  struct AVTreeNode *node = NULL;
307  int ret;
308 
309  /* load glyph into s->face->glyph */
310  if (FT_Load_Char(s->face, code, s->ft_load_flags))
311  return AVERROR(EINVAL);
312 
313  glyph = av_mallocz(sizeof(*glyph));
314  if (!glyph) {
315  ret = AVERROR(ENOMEM);
316  goto error;
317  }
318  glyph->code = code;
319 
320  if (FT_Get_Glyph(s->face->glyph, &glyph->glyph)) {
321  ret = AVERROR(EINVAL);
322  goto error;
323  }
324  if (s->borderw) {
325  glyph->border_glyph = glyph->glyph;
326  if (FT_Glyph_StrokeBorder(&glyph->border_glyph, s->stroker, 0, 0) ||
327  FT_Glyph_To_Bitmap(&glyph->border_glyph, FT_RENDER_MODE_NORMAL, 0, 1)) {
328  ret = AVERROR_EXTERNAL;
329  goto error;
330  }
331  bitmapglyph = (FT_BitmapGlyph) glyph->border_glyph;
332  glyph->border_bitmap = bitmapglyph->bitmap;
333  }
334  if (FT_Glyph_To_Bitmap(&glyph->glyph, FT_RENDER_MODE_NORMAL, 0, 1)) {
335  ret = AVERROR_EXTERNAL;
336  goto error;
337  }
338  bitmapglyph = (FT_BitmapGlyph) glyph->glyph;
339 
340  glyph->bitmap = bitmapglyph->bitmap;
341  glyph->bitmap_left = bitmapglyph->left;
342  glyph->bitmap_top = bitmapglyph->top;
343  glyph->advance = s->face->glyph->advance.x >> 6;
344 
345  /* measure text height to calculate text_height (or the maximum text height) */
346  FT_Glyph_Get_CBox(glyph->glyph, ft_glyph_bbox_pixels, &glyph->bbox);
347 
348  /* cache the newly created glyph */
349  if (!(node = av_tree_node_alloc())) {
350  ret = AVERROR(ENOMEM);
351  goto error;
352  }
353  av_tree_insert(&s->glyphs, glyph, glyph_cmp, &node);
354 
355  if (glyph_ptr)
356  *glyph_ptr = glyph;
357  return 0;
358 
359 error:
360  if (glyph)
361  av_freep(&glyph->glyph);
362 
363  av_freep(&glyph);
364  av_freep(&node);
365  return ret;
366 }
367 
368 static int load_font_file(AVFilterContext *ctx, const char *path, int index)
369 {
370  DrawTextContext *s = ctx->priv;
371  int err;
372 
373  err = FT_New_Face(s->library, path, index, &s->face);
374  if (err) {
375  av_log(ctx, AV_LOG_ERROR, "Could not load font \"%s\": %s\n",
376  s->fontfile, FT_ERRMSG(err));
377  return AVERROR(EINVAL);
378  }
379  return 0;
380 }
381 
382 #if CONFIG_LIBFONTCONFIG
383 static int load_font_fontconfig(AVFilterContext *ctx)
384 {
385  DrawTextContext *s = ctx->priv;
386  FcConfig *fontconfig;
387  FcPattern *pat, *best;
388  FcResult result = FcResultMatch;
389  FcChar8 *filename;
390  int index;
391  double size;
392  int err = AVERROR(ENOENT);
393 
394  fontconfig = FcInitLoadConfigAndFonts();
395  if (!fontconfig) {
396  av_log(ctx, AV_LOG_ERROR, "impossible to init fontconfig\n");
397  return AVERROR_UNKNOWN;
398  }
399  pat = FcNameParse(s->fontfile ? s->fontfile :
400  (uint8_t *)(intptr_t)"default");
401  if (!pat) {
402  av_log(ctx, AV_LOG_ERROR, "could not parse fontconfig pat");
403  return AVERROR(EINVAL);
404  }
405 
406  FcPatternAddString(pat, FC_FAMILY, s->font);
407  if (s->fontsize)
408  FcPatternAddDouble(pat, FC_SIZE, (double)s->fontsize);
409 
410  FcDefaultSubstitute(pat);
411 
412  if (!FcConfigSubstitute(fontconfig, pat, FcMatchPattern)) {
413  av_log(ctx, AV_LOG_ERROR, "could not substitue fontconfig options"); /* very unlikely */
414  FcPatternDestroy(pat);
415  return AVERROR(ENOMEM);
416  }
417 
418  best = FcFontMatch(fontconfig, pat, &result);
419  FcPatternDestroy(pat);
420 
421  if (!best || result != FcResultMatch) {
422  av_log(ctx, AV_LOG_ERROR,
423  "Cannot find a valid font for the family %s\n",
424  s->font);
425  goto fail;
426  }
427 
428  if (
429  FcPatternGetInteger(best, FC_INDEX, 0, &index ) != FcResultMatch ||
430  FcPatternGetDouble (best, FC_SIZE, 0, &size ) != FcResultMatch) {
431  av_log(ctx, AV_LOG_ERROR, "impossible to find font information");
432  return AVERROR(EINVAL);
433  }
434 
435  if (FcPatternGetString(best, FC_FILE, 0, &filename) != FcResultMatch) {
436  av_log(ctx, AV_LOG_ERROR, "No file path for %s\n",
437  s->font);
438  goto fail;
439  }
440 
441  av_log(ctx, AV_LOG_INFO, "Using \"%s\"\n", filename);
442  if (!s->fontsize)
443  s->fontsize = size + 0.5;
444 
445  err = load_font_file(ctx, filename, index);
446  if (err)
447  return err;
448  FcConfigDestroy(fontconfig);
449 fail:
450  FcPatternDestroy(best);
451  return err;
452 }
453 #endif
454 
455 static int load_font(AVFilterContext *ctx)
456 {
457  DrawTextContext *s = ctx->priv;
458  int err;
459 
460  /* load the face, and set up the encoding, which is by default UTF-8 */
461  err = load_font_file(ctx, s->fontfile, 0);
462  if (!err)
463  return 0;
464 #if CONFIG_LIBFONTCONFIG
465  err = load_font_fontconfig(ctx);
466  if (!err)
467  return 0;
468 #endif
469  return err;
470 }
471 
473 {
474  DrawTextContext *s = ctx->priv;
475  int err;
476  uint8_t *textbuf;
477  uint8_t *tmp;
478  size_t textbuf_size;
479 
480  if ((err = av_file_map(s->textfile, &textbuf, &textbuf_size, 0, ctx)) < 0) {
481  av_log(ctx, AV_LOG_ERROR,
482  "The text file '%s' could not be read or is empty\n",
483  s->textfile);
484  return err;
485  }
486 
487  if (textbuf_size > SIZE_MAX - 1 || !(tmp = av_realloc(s->text, textbuf_size + 1))) {
488  av_file_unmap(textbuf, textbuf_size);
489  return AVERROR(ENOMEM);
490  }
491  s->text = tmp;
492  memcpy(s->text, textbuf, textbuf_size);
493  s->text[textbuf_size] = 0;
494  av_file_unmap(textbuf, textbuf_size);
495 
496  return 0;
497 }
498 
499 static inline int is_newline(uint32_t c)
500 {
501  return c == '\n' || c == '\r' || c == '\f' || c == '\v';
502 }
503 
504 #if CONFIG_LIBFRIBIDI
505 static int shape_text(AVFilterContext *ctx)
506 {
507  DrawTextContext *s = ctx->priv;
508  uint8_t *tmp;
509  int ret = AVERROR(ENOMEM);
510  static const FriBidiFlags flags = FRIBIDI_FLAGS_DEFAULT |
511  FRIBIDI_FLAGS_ARABIC;
512  FriBidiChar *unicodestr = NULL;
513  FriBidiStrIndex len;
514  FriBidiParType direction = FRIBIDI_PAR_LTR;
515  FriBidiStrIndex line_start = 0;
516  FriBidiStrIndex line_end = 0;
517  FriBidiLevel *embedding_levels = NULL;
518  FriBidiArabicProp *ar_props = NULL;
519  FriBidiCharType *bidi_types = NULL;
520  FriBidiStrIndex i,j;
521 
522  len = strlen(s->text);
523  if (!(unicodestr = av_malloc_array(len, sizeof(*unicodestr)))) {
524  goto out;
525  }
526  len = fribidi_charset_to_unicode(FRIBIDI_CHAR_SET_UTF8,
527  s->text, len, unicodestr);
528 
529  bidi_types = av_malloc_array(len, sizeof(*bidi_types));
530  if (!bidi_types) {
531  goto out;
532  }
533 
534  fribidi_get_bidi_types(unicodestr, len, bidi_types);
535 
536  embedding_levels = av_malloc_array(len, sizeof(*embedding_levels));
537  if (!embedding_levels) {
538  goto out;
539  }
540 
541  if (!fribidi_get_par_embedding_levels(bidi_types, len, &direction,
542  embedding_levels)) {
543  goto out;
544  }
545 
546  ar_props = av_malloc_array(len, sizeof(*ar_props));
547  if (!ar_props) {
548  goto out;
549  }
550 
551  fribidi_get_joining_types(unicodestr, len, ar_props);
552  fribidi_join_arabic(bidi_types, len, embedding_levels, ar_props);
553  fribidi_shape(flags, embedding_levels, len, ar_props, unicodestr);
554 
555  for (line_end = 0, line_start = 0; line_end < len; line_end++) {
556  if (is_newline(unicodestr[line_end]) || line_end == len - 1) {
557  if (!fribidi_reorder_line(flags, bidi_types,
558  line_end - line_start + 1, line_start,
559  direction, embedding_levels, unicodestr,
560  NULL)) {
561  goto out;
562  }
563  line_start = line_end + 1;
564  }
565  }
566 
567  /* Remove zero-width fill chars put in by libfribidi */
568  for (i = 0, j = 0; i < len; i++)
569  if (unicodestr[i] != FRIBIDI_CHAR_FILL)
570  unicodestr[j++] = unicodestr[i];
571  len = j;
572 
573  if (!(tmp = av_realloc(s->text, (len * 4 + 1) * sizeof(*s->text)))) {
574  /* Use len * 4, as a unicode character can be up to 4 bytes in UTF-8 */
575  goto out;
576  }
577 
578  s->text = tmp;
579  len = fribidi_unicode_to_charset(FRIBIDI_CHAR_SET_UTF8,
580  unicodestr, len, s->text);
581  ret = 0;
582 
583 out:
584  av_free(unicodestr);
585  av_free(embedding_levels);
586  av_free(ar_props);
587  av_free(bidi_types);
588  return ret;
589 }
590 #endif
591 
592 static av_cold int init(AVFilterContext *ctx)
593 {
594  int err;
595  DrawTextContext *s = ctx->priv;
596  Glyph *glyph;
597 
598  if (!s->fontfile && !CONFIG_LIBFONTCONFIG) {
599  av_log(ctx, AV_LOG_ERROR, "No font filename provided\n");
600  return AVERROR(EINVAL);
601  }
602 
603  if (s->textfile) {
604  if (s->text) {
605  av_log(ctx, AV_LOG_ERROR,
606  "Both text and text file provided. Please provide only one\n");
607  return AVERROR(EINVAL);
608  }
609  if ((err = load_textfile(ctx)) < 0)
610  return err;
611  }
612 
613 #if CONFIG_LIBFRIBIDI
614  if (s->text_shaping)
615  if ((err = shape_text(ctx)) < 0)
616  return err;
617 #endif
618 
619  if (s->reload && !s->textfile)
620  av_log(ctx, AV_LOG_WARNING, "No file to reload\n");
621 
622  if (s->tc_opt_string) {
623  int ret = av_timecode_init_from_string(&s->tc, s->tc_rate,
624  s->tc_opt_string, ctx);
625  if (ret < 0)
626  return ret;
627  if (s->tc24hmax)
629  if (!s->text)
630  s->text = av_strdup("");
631  }
632 
633  if (!s->text) {
634  av_log(ctx, AV_LOG_ERROR,
635  "Either text, a valid file or a timecode must be provided\n");
636  return AVERROR(EINVAL);
637  }
638 
639  if ((err = FT_Init_FreeType(&(s->library)))) {
640  av_log(ctx, AV_LOG_ERROR,
641  "Could not load FreeType: %s\n", FT_ERRMSG(err));
642  return AVERROR(EINVAL);
643  }
644 
645  err = load_font(ctx);
646  if (err)
647  return err;
648  if (!s->fontsize)
649  s->fontsize = 16;
650  if ((err = FT_Set_Pixel_Sizes(s->face, 0, s->fontsize))) {
651  av_log(ctx, AV_LOG_ERROR, "Could not set font size to %d pixels: %s\n",
652  s->fontsize, FT_ERRMSG(err));
653  return AVERROR(EINVAL);
654  }
655 
656  if (s->borderw) {
657  if (FT_Stroker_New(s->library, &s->stroker)) {
658  av_log(ctx, AV_LOG_ERROR, "Coult not init FT stroker\n");
659  return AVERROR_EXTERNAL;
660  }
661  FT_Stroker_Set(s->stroker, s->borderw << 6, FT_STROKER_LINECAP_ROUND,
662  FT_STROKER_LINEJOIN_ROUND, 0);
663  }
664 
665  s->use_kerning = FT_HAS_KERNING(s->face);
666 
667  /* load the fallback glyph with code 0 */
668  load_glyph(ctx, NULL, 0);
669 
670  /* set the tabsize in pixels */
671  if ((err = load_glyph(ctx, &glyph, ' ')) < 0) {
672  av_log(ctx, AV_LOG_ERROR, "Could not set tabsize.\n");
673  return err;
674  }
675  s->tabsize *= glyph->advance;
676 
677  if (s->exp_mode == EXP_STRFTIME &&
678  (strchr(s->text, '%') || strchr(s->text, '\\')))
679  av_log(ctx, AV_LOG_WARNING, "expansion=strftime is deprecated.\n");
680 
683 
684  return 0;
685 }
686 
688 {
690 }
691 
692 static int glyph_enu_free(void *opaque, void *elem)
693 {
694  Glyph *glyph = elem;
695 
696  FT_Done_Glyph(glyph->glyph);
697  FT_Done_Glyph(glyph->border_glyph);
698  av_free(elem);
699  return 0;
700 }
701 
702 static av_cold void uninit(AVFilterContext *ctx)
703 {
704  DrawTextContext *s = ctx->priv;
705 
706  av_expr_free(s->x_pexpr);
707  av_expr_free(s->y_pexpr);
708  s->x_pexpr = s->y_pexpr = NULL;
709  av_freep(&s->positions);
710  s->nb_positions = 0;
711 
712 
715  s->glyphs = NULL;
716 
717  FT_Done_Face(s->face);
718  FT_Stroker_Done(s->stroker);
719  FT_Done_FreeType(s->library);
720 
723 }
724 
725 static int config_input(AVFilterLink *inlink)
726 {
727  AVFilterContext *ctx = inlink->dst;
728  DrawTextContext *s = ctx->priv;
729  int ret;
730 
731  ff_draw_init(&s->dc, inlink->format, 0);
732  ff_draw_color(&s->dc, &s->fontcolor, s->fontcolor.rgba);
735  ff_draw_color(&s->dc, &s->boxcolor, s->boxcolor.rgba);
736 
737  s->var_values[VAR_w] = s->var_values[VAR_W] = s->var_values[VAR_MAIN_W] = inlink->w;
738  s->var_values[VAR_h] = s->var_values[VAR_H] = s->var_values[VAR_MAIN_H] = inlink->h;
740  s->var_values[VAR_DAR] = (double)inlink->w / inlink->h * s->var_values[VAR_SAR];
741  s->var_values[VAR_HSUB] = 1 << s->dc.hsub_max;
742  s->var_values[VAR_VSUB] = 1 << s->dc.vsub_max;
743  s->var_values[VAR_X] = NAN;
744  s->var_values[VAR_Y] = NAN;
745  s->var_values[VAR_T] = NAN;
746 
748 
749  av_expr_free(s->x_pexpr);
750  av_expr_free(s->y_pexpr);
751  s->x_pexpr = s->y_pexpr = NULL;
752 
753  if ((ret = av_expr_parse(&s->x_pexpr, s->x_expr, var_names,
754  NULL, NULL, fun2_names, fun2, 0, ctx)) < 0 ||
755  (ret = av_expr_parse(&s->y_pexpr, s->y_expr, var_names,
756  NULL, NULL, fun2_names, fun2, 0, ctx)) < 0 ||
757  (ret = av_expr_parse(&s->a_pexpr, s->a_expr, var_names,
758  NULL, NULL, fun2_names, fun2, 0, ctx)) < 0)
759 
760  return AVERROR(EINVAL);
761 
762  return 0;
763 }
764 
765 static int command(AVFilterContext *ctx, const char *cmd, const char *arg, char *res, int res_len, int flags)
766 {
767  DrawTextContext *s = ctx->priv;
768 
769  if (!strcmp(cmd, "reinit")) {
770  int ret;
771  uninit(ctx);
772  s->reinit = 1;
773  if ((ret = av_set_options_string(ctx, arg, "=", ":")) < 0)
774  return ret;
775  if ((ret = init(ctx)) < 0)
776  return ret;
777  return config_input(ctx->inputs[0]);
778  }
779 
780  return AVERROR(ENOSYS);
781 }
782 
783 static int func_pict_type(AVFilterContext *ctx, AVBPrint *bp,
784  char *fct, unsigned argc, char **argv, int tag)
785 {
786  DrawTextContext *s = ctx->priv;
787 
789  return 0;
790 }
791 
792 static int func_pts(AVFilterContext *ctx, AVBPrint *bp,
793  char *fct, unsigned argc, char **argv, int tag)
794 {
795  DrawTextContext *s = ctx->priv;
796  const char *fmt;
797  double pts = s->var_values[VAR_T];
798  int ret;
799 
800  fmt = argc >= 1 ? argv[0] : "flt";
801  if (argc >= 2) {
802  int64_t delta;
803  if ((ret = av_parse_time(&delta, argv[1], 1)) < 0) {
804  av_log(ctx, AV_LOG_ERROR, "Invalid delta '%s'\n", argv[1]);
805  return ret;
806  }
807  pts += (double)delta / AV_TIME_BASE;
808  }
809  if (!strcmp(fmt, "flt")) {
810  av_bprintf(bp, "%.6f", s->var_values[VAR_T]);
811  } else if (!strcmp(fmt, "hms")) {
812  if (isnan(pts)) {
813  av_bprintf(bp, " ??:??:??.???");
814  } else {
815  int64_t ms = round(pts * 1000);
816  char sign = ' ';
817  if (ms < 0) {
818  sign = '-';
819  ms = -ms;
820  }
821  av_bprintf(bp, "%c%02d:%02d:%02d.%03d", sign,
822  (int)(ms / (60 * 60 * 1000)),
823  (int)(ms / (60 * 1000)) % 60,
824  (int)(ms / 1000) % 60,
825  (int)ms % 1000);
826  }
827  } else {
828  av_log(ctx, AV_LOG_ERROR, "Invalid format '%s'\n", fmt);
829  return AVERROR(EINVAL);
830  }
831  return 0;
832 }
833 
834 static int func_frame_num(AVFilterContext *ctx, AVBPrint *bp,
835  char *fct, unsigned argc, char **argv, int tag)
836 {
837  DrawTextContext *s = ctx->priv;
838 
839  av_bprintf(bp, "%d", (int)s->var_values[VAR_N]);
840  return 0;
841 }
842 
843 static int func_metadata(AVFilterContext *ctx, AVBPrint *bp,
844  char *fct, unsigned argc, char **argv, int tag)
845 {
846  DrawTextContext *s = ctx->priv;
847  AVDictionaryEntry *e = av_dict_get(s->metadata, argv[0], NULL, 0);
848 
849  if (e && e->value)
850  av_bprintf(bp, "%s", e->value);
851  return 0;
852 }
853 
854 static int func_strftime(AVFilterContext *ctx, AVBPrint *bp,
855  char *fct, unsigned argc, char **argv, int tag)
856 {
857  const char *fmt = argc ? argv[0] : "%Y-%m-%d %H:%M:%S";
858  time_t now;
859  struct tm tm;
860 
861  time(&now);
862  if (tag == 'L')
863  localtime_r(&now, &tm);
864  else
865  tm = *gmtime_r(&now, &tm);
866  av_bprint_strftime(bp, fmt, &tm);
867  return 0;
868 }
869 
870 static int func_eval_expr(AVFilterContext *ctx, AVBPrint *bp,
871  char *fct, unsigned argc, char **argv, int tag)
872 {
873  DrawTextContext *s = ctx->priv;
874  double res;
875  int ret;
876 
877  ret = av_expr_parse_and_eval(&res, argv[0], var_names, s->var_values,
879  &s->prng, 0, ctx);
880  if (ret < 0)
881  av_log(ctx, AV_LOG_ERROR,
882  "Expression '%s' for the expr text expansion function is not valid\n",
883  argv[0]);
884  else
885  av_bprintf(bp, "%f", res);
886 
887  return ret;
888 }
889 
890 static int func_eval_expr_int_format(AVFilterContext *ctx, AVBPrint *bp,
891  char *fct, unsigned argc, char **argv, int tag)
892 {
893  DrawTextContext *s = ctx->priv;
894  double res;
895  int intval;
896  int ret;
897  unsigned int positions = 0;
898  char fmt_str[30] = "%";
899 
900  /*
901  * argv[0] expression to be converted to `int`
902  * argv[1] format: 'x', 'X', 'd' or 'u'
903  * argv[2] positions printed (optional)
904  */
905 
906  ret = av_expr_parse_and_eval(&res, argv[0], var_names, s->var_values,
908  &s->prng, 0, ctx);
909  if (ret < 0) {
910  av_log(ctx, AV_LOG_ERROR,
911  "Expression '%s' for the expr text expansion function is not valid\n",
912  argv[0]);
913  return ret;
914  }
915 
916  if (!strchr("xXdu", argv[1][0])) {
917  av_log(ctx, AV_LOG_ERROR, "Invalid format '%c' specified,"
918  " allowed values: 'x', 'X', 'd', 'u'\n", argv[1][0]);
919  return AVERROR(EINVAL);
920  }
921 
922  if (argc == 3) {
923  ret = sscanf(argv[2], "%u", &positions);
924  if (ret != 1) {
925  av_log(ctx, AV_LOG_ERROR, "expr_int_format(): Invalid number of positions"
926  " to print: '%s'\n", argv[2]);
927  return AVERROR(EINVAL);
928  }
929  }
930 
931  feclearexcept(FE_ALL_EXCEPT);
932  intval = res;
933  if ((ret = fetestexcept(FE_INVALID|FE_OVERFLOW|FE_UNDERFLOW))) {
934  av_log(ctx, AV_LOG_ERROR, "Conversion of floating-point result to int failed. Control register: 0x%08x. Conversion result: %d\n", ret, intval);
935  return AVERROR(EINVAL);
936  }
937 
938  if (argc == 3)
939  av_strlcatf(fmt_str, sizeof(fmt_str), "0%u", positions);
940  av_strlcatf(fmt_str, sizeof(fmt_str), "%c", argv[1][0]);
941 
942  av_log(ctx, AV_LOG_DEBUG, "Formatting value %f (expr '%s') with spec '%s'\n",
943  res, argv[0], fmt_str);
944 
945  av_bprintf(bp, fmt_str, intval);
946 
947  return 0;
948 }
949 
950 static const struct drawtext_function {
951  const char *name;
952  unsigned argc_min, argc_max;
953  int tag; /**< opaque argument to func */
954  int (*func)(AVFilterContext *, AVBPrint *, char *, unsigned, char **, int);
955 } functions[] = {
956  { "expr", 1, 1, 0, func_eval_expr },
957  { "e", 1, 1, 0, func_eval_expr },
958  { "expr_int_format", 2, 3, 0, func_eval_expr_int_format },
959  { "eif", 2, 3, 0, func_eval_expr_int_format },
960  { "pict_type", 0, 0, 0, func_pict_type },
961  { "pts", 0, 2, 0, func_pts },
962  { "gmtime", 0, 1, 'G', func_strftime },
963  { "localtime", 0, 1, 'L', func_strftime },
964  { "frame_num", 0, 0, 0, func_frame_num },
965  { "n", 0, 0, 0, func_frame_num },
966  { "metadata", 1, 1, 0, func_metadata },
967 };
968 
969 static int eval_function(AVFilterContext *ctx, AVBPrint *bp, char *fct,
970  unsigned argc, char **argv)
971 {
972  unsigned i;
973 
974  for (i = 0; i < FF_ARRAY_ELEMS(functions); i++) {
975  if (strcmp(fct, functions[i].name))
976  continue;
977  if (argc < functions[i].argc_min) {
978  av_log(ctx, AV_LOG_ERROR, "%%{%s} requires at least %d arguments\n",
979  fct, functions[i].argc_min);
980  return AVERROR(EINVAL);
981  }
982  if (argc > functions[i].argc_max) {
983  av_log(ctx, AV_LOG_ERROR, "%%{%s} requires at most %d arguments\n",
984  fct, functions[i].argc_max);
985  return AVERROR(EINVAL);
986  }
987  break;
988  }
989  if (i >= FF_ARRAY_ELEMS(functions)) {
990  av_log(ctx, AV_LOG_ERROR, "%%{%s} is not known\n", fct);
991  return AVERROR(EINVAL);
992  }
993  return functions[i].func(ctx, bp, fct, argc, argv, functions[i].tag);
994 }
995 
996 static int expand_function(AVFilterContext *ctx, AVBPrint *bp, char **rtext)
997 {
998  const char *text = *rtext;
999  char *argv[16] = { NULL };
1000  unsigned argc = 0, i;
1001  int ret;
1002 
1003  if (*text != '{') {
1004  av_log(ctx, AV_LOG_ERROR, "Stray %% near '%s'\n", text);
1005  return AVERROR(EINVAL);
1006  }
1007  text++;
1008  while (1) {
1009  if (!(argv[argc++] = av_get_token(&text, ":}"))) {
1010  ret = AVERROR(ENOMEM);
1011  goto end;
1012  }
1013  if (!*text) {
1014  av_log(ctx, AV_LOG_ERROR, "Unterminated %%{} near '%s'\n", *rtext);
1015  ret = AVERROR(EINVAL);
1016  goto end;
1017  }
1018  if (argc == FF_ARRAY_ELEMS(argv))
1019  av_freep(&argv[--argc]); /* error will be caught later */
1020  if (*text == '}')
1021  break;
1022  text++;
1023  }
1024 
1025  if ((ret = eval_function(ctx, bp, argv[0], argc - 1, argv + 1)) < 0)
1026  goto end;
1027  ret = 0;
1028  *rtext = (char *)text + 1;
1029 
1030 end:
1031  for (i = 0; i < argc; i++)
1032  av_freep(&argv[i]);
1033  return ret;
1034 }
1035 
1036 static int expand_text(AVFilterContext *ctx, char *text, AVBPrint *bp)
1037 {
1038  int ret;
1039 
1040  av_bprint_clear(bp);
1041  while (*text) {
1042  if (*text == '\\' && text[1]) {
1043  av_bprint_chars(bp, text[1], 1);
1044  text += 2;
1045  } else if (*text == '%') {
1046  text++;
1047  if ((ret = expand_function(ctx, bp, &text)) < 0)
1048  return ret;
1049  } else {
1050  av_bprint_chars(bp, *text, 1);
1051  text++;
1052  }
1053  }
1054  if (!av_bprint_is_complete(bp))
1055  return AVERROR(ENOMEM);
1056  return 0;
1057 }
1058 
1060  int width, int height,
1061  FFDrawColor *color,
1062  int x, int y, int borderw)
1063 {
1064  char *text = s->expanded_text.str;
1065  uint32_t code = 0;
1066  int i, x1, y1;
1067  uint8_t *p;
1068  Glyph *glyph = NULL;
1069 
1070  for (i = 0, p = text; *p; i++) {
1071  FT_Bitmap bitmap;
1072  Glyph dummy = { 0 };
1073  GET_UTF8(code, *p++, continue;);
1074 
1075  /* skip new line chars, just go to new line */
1076  if (code == '\n' || code == '\r' || code == '\t')
1077  continue;
1078 
1079  dummy.code = code;
1080  glyph = av_tree_find(s->glyphs, &dummy, (void *)glyph_cmp, NULL);
1081 
1082  bitmap = borderw ? glyph->border_bitmap : glyph->bitmap;
1083 
1084  if (glyph->bitmap.pixel_mode != FT_PIXEL_MODE_MONO &&
1085  glyph->bitmap.pixel_mode != FT_PIXEL_MODE_GRAY)
1086  return AVERROR(EINVAL);
1087 
1088  x1 = s->positions[i].x+s->x+x - borderw;
1089  y1 = s->positions[i].y+s->y+y - borderw;
1090 
1091  ff_blend_mask(&s->dc, color,
1092  frame->data, frame->linesize, width, height,
1093  bitmap.buffer, bitmap.pitch,
1094  bitmap.width, bitmap.rows,
1095  bitmap.pixel_mode == FT_PIXEL_MODE_MONO ? 0 : 3,
1096  0, x1, y1);
1097  }
1098 
1099  return 0;
1100 }
1101 
1102 
1104 {
1105  *color = incolor;
1106  color->rgba[3] = (color->rgba[3] * s->alpha) / 255;
1107  ff_draw_color(&s->dc, color, color->rgba);
1108 }
1109 
1111 {
1112  double alpha = av_expr_eval(s->a_pexpr, s->var_values, &s->prng);
1113 
1114  if (isnan(alpha))
1115  return;
1116 
1117  if (alpha >= 1.0)
1118  s->alpha = 255;
1119  else if (alpha <= 0)
1120  s->alpha = 0;
1121  else
1122  s->alpha = 256 * alpha;
1123 }
1124 
1126  int width, int height)
1127 {
1128  DrawTextContext *s = ctx->priv;
1129  AVFilterLink *inlink = ctx->inputs[0];
1130 
1131  uint32_t code = 0, prev_code = 0;
1132  int x = 0, y = 0, i = 0, ret;
1133  int max_text_line_w = 0, len;
1134  int box_w, box_h;
1135  char *text;
1136  uint8_t *p;
1137  int y_min = 32000, y_max = -32000;
1138  int x_min = 32000, x_max = -32000;
1139  FT_Vector delta;
1140  Glyph *glyph = NULL, *prev_glyph = NULL;
1141  Glyph dummy = { 0 };
1142 
1143  time_t now = time(0);
1144  struct tm ltime;
1145  AVBPrint *bp = &s->expanded_text;
1146 
1147  FFDrawColor fontcolor;
1148  FFDrawColor shadowcolor;
1149  FFDrawColor bordercolor;
1150  FFDrawColor boxcolor;
1151 
1152  av_bprint_clear(bp);
1153 
1154  if(s->basetime != AV_NOPTS_VALUE)
1155  now= frame->pts*av_q2d(ctx->inputs[0]->time_base) + s->basetime/1000000;
1156 
1157  switch (s->exp_mode) {
1158  case EXP_NONE:
1159  av_bprintf(bp, "%s", s->text);
1160  break;
1161  case EXP_NORMAL:
1162  if ((ret = expand_text(ctx, s->text, &s->expanded_text)) < 0)
1163  return ret;
1164  break;
1165  case EXP_STRFTIME:
1166  localtime_r(&now, &ltime);
1167  av_bprint_strftime(bp, s->text, &ltime);
1168  break;
1169  }
1170 
1171  if (s->tc_opt_string) {
1172  char tcbuf[AV_TIMECODE_STR_SIZE];
1173  av_timecode_make_string(&s->tc, tcbuf, inlink->frame_count);
1174  av_bprint_clear(bp);
1175  av_bprintf(bp, "%s%s", s->text, tcbuf);
1176  }
1177 
1178  if (!av_bprint_is_complete(bp))
1179  return AVERROR(ENOMEM);
1180  text = s->expanded_text.str;
1181  if ((len = s->expanded_text.len) > s->nb_positions) {
1182  if (!(s->positions =
1183  av_realloc(s->positions, len*sizeof(*s->positions))))
1184  return AVERROR(ENOMEM);
1185  s->nb_positions = len;
1186  }
1187 
1188  if (s->fontcolor_expr[0]) {
1189  /* If expression is set, evaluate and replace the static value */
1191  if ((ret = expand_text(ctx, s->fontcolor_expr, &s->expanded_fontcolor)) < 0)
1192  return ret;
1194  return AVERROR(ENOMEM);
1195  av_log(s, AV_LOG_DEBUG, "Evaluated fontcolor is '%s'\n", s->expanded_fontcolor.str);
1196  ret = av_parse_color(s->fontcolor.rgba, s->expanded_fontcolor.str, -1, s);
1197  if (ret)
1198  return ret;
1199  ff_draw_color(&s->dc, &s->fontcolor, s->fontcolor.rgba);
1200  }
1201 
1202  x = 0;
1203  y = 0;
1204 
1205  /* load and cache glyphs */
1206  for (i = 0, p = text; *p; i++) {
1207  GET_UTF8(code, *p++, continue;);
1208 
1209  /* get glyph */
1210  dummy.code = code;
1211  glyph = av_tree_find(s->glyphs, &dummy, glyph_cmp, NULL);
1212  if (!glyph) {
1213  load_glyph(ctx, &glyph, code);
1214  }
1215 
1216  y_min = FFMIN(glyph->bbox.yMin, y_min);
1217  y_max = FFMAX(glyph->bbox.yMax, y_max);
1218  x_min = FFMIN(glyph->bbox.xMin, x_min);
1219  x_max = FFMAX(glyph->bbox.xMax, x_max);
1220  }
1221  s->max_glyph_h = y_max - y_min;
1222  s->max_glyph_w = x_max - x_min;
1223 
1224  /* compute and save position for each glyph */
1225  glyph = NULL;
1226  for (i = 0, p = text; *p; i++) {
1227  GET_UTF8(code, *p++, continue;);
1228 
1229  /* skip the \n in the sequence \r\n */
1230  if (prev_code == '\r' && code == '\n')
1231  continue;
1232 
1233  prev_code = code;
1234  if (is_newline(code)) {
1235 
1236  max_text_line_w = FFMAX(max_text_line_w, x);
1237  y += s->max_glyph_h;
1238  x = 0;
1239  continue;
1240  }
1241 
1242  /* get glyph */
1243  prev_glyph = glyph;
1244  dummy.code = code;
1245  glyph = av_tree_find(s->glyphs, &dummy, glyph_cmp, NULL);
1246 
1247  /* kerning */
1248  if (s->use_kerning && prev_glyph && glyph->code) {
1249  FT_Get_Kerning(s->face, prev_glyph->code, glyph->code,
1250  ft_kerning_default, &delta);
1251  x += delta.x >> 6;
1252  }
1253 
1254  /* save position */
1255  s->positions[i].x = x + glyph->bitmap_left;
1256  s->positions[i].y = y - glyph->bitmap_top + y_max;
1257  if (code == '\t') x = (x / s->tabsize + 1)*s->tabsize;
1258  else x += glyph->advance;
1259  }
1260 
1261  max_text_line_w = FFMAX(x, max_text_line_w);
1262 
1263  s->var_values[VAR_TW] = s->var_values[VAR_TEXT_W] = max_text_line_w;
1265 
1268  s->var_values[VAR_MAX_GLYPH_A] = s->var_values[VAR_ASCENT ] = y_max;
1270 
1272 
1273  s->x = s->var_values[VAR_X] = av_expr_eval(s->x_pexpr, s->var_values, &s->prng);
1274  s->y = s->var_values[VAR_Y] = av_expr_eval(s->y_pexpr, s->var_values, &s->prng);
1275  s->x = s->var_values[VAR_X] = av_expr_eval(s->x_pexpr, s->var_values, &s->prng);
1276 
1277  update_alpha(s);
1278  update_color_with_alpha(s, &fontcolor , s->fontcolor );
1279  update_color_with_alpha(s, &shadowcolor, s->shadowcolor);
1280  update_color_with_alpha(s, &bordercolor, s->bordercolor);
1281  update_color_with_alpha(s, &boxcolor , s->boxcolor );
1282 
1283  box_w = FFMIN(width - 1 , max_text_line_w);
1284  box_h = FFMIN(height - 1, y + s->max_glyph_h);
1285 
1286  /* draw box */
1287  if (s->draw_box)
1288  ff_blend_rectangle(&s->dc, &boxcolor,
1289  frame->data, frame->linesize, width, height,
1290  s->x - s->boxborderw, s->y - s->boxborderw,
1291  box_w + s->boxborderw * 2, box_h + s->boxborderw * 2);
1292 
1293  if (s->shadowx || s->shadowy) {
1294  if ((ret = draw_glyphs(s, frame, width, height,
1295  &shadowcolor, s->shadowx, s->shadowy, 0)) < 0)
1296  return ret;
1297  }
1298 
1299  if (s->borderw) {
1300  if ((ret = draw_glyphs(s, frame, width, height,
1301  &bordercolor, 0, 0, s->borderw)) < 0)
1302  return ret;
1303  }
1304  if ((ret = draw_glyphs(s, frame, width, height,
1305  &fontcolor, 0, 0, 0)) < 0)
1306  return ret;
1307 
1308  return 0;
1309 }
1310 
1312 {
1313  AVFilterContext *ctx = inlink->dst;
1314  AVFilterLink *outlink = ctx->outputs[0];
1315  DrawTextContext *s = ctx->priv;
1316  int ret;
1317 
1318  if (s->reload) {
1319  if ((ret = load_textfile(ctx)) < 0) {
1320  av_frame_free(&frame);
1321  return ret;
1322  }
1323 #if CONFIG_LIBFRIBIDI
1324  if (s->text_shaping)
1325  if ((ret = shape_text(ctx)) < 0) {
1326  av_frame_free(&frame);
1327  return ret;
1328  }
1329 #endif
1330  }
1331 
1332  s->var_values[VAR_N] = inlink->frame_count+s->start_number;
1333  s->var_values[VAR_T] = frame->pts == AV_NOPTS_VALUE ?
1334  NAN : frame->pts * av_q2d(inlink->time_base);
1335 
1336  s->var_values[VAR_PICT_TYPE] = frame->pict_type;
1337  s->metadata = av_frame_get_metadata(frame);
1338 
1339  draw_text(ctx, frame, frame->width, frame->height);
1340 
1341  av_log(ctx, AV_LOG_DEBUG, "n:%d t:%f text_w:%d text_h:%d x:%d y:%d\n",
1342  (int)s->var_values[VAR_N], s->var_values[VAR_T],
1343  (int)s->var_values[VAR_TEXT_W], (int)s->var_values[VAR_TEXT_H],
1344  s->x, s->y);
1345 
1346  return ff_filter_frame(outlink, frame);
1347 }
1348 
1350  {
1351  .name = "default",
1352  .type = AVMEDIA_TYPE_VIDEO,
1353  .filter_frame = filter_frame,
1354  .config_props = config_input,
1355  .needs_writable = 1,
1356  },
1357  { NULL }
1358 };
1359 
1361  {
1362  .name = "default",
1363  .type = AVMEDIA_TYPE_VIDEO,
1364  },
1365  { NULL }
1366 };
1367 
1369  .name = "drawtext",
1370  .description = NULL_IF_CONFIG_SMALL("Draw text on top of video frames using libfreetype library."),
1371  .priv_size = sizeof(DrawTextContext),
1372  .priv_class = &drawtext_class,
1373  .init = init,
1374  .uninit = uninit,
1376  .inputs = avfilter_vf_drawtext_inputs,
1377  .outputs = avfilter_vf_drawtext_outputs,
1380 };