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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"
55 #include "libavutil/time_internal.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 {
111  VAR_DAR,
112  VAR_HSUB, VAR_VSUB,
113  VAR_LINE_H, VAR_LH,
114  VAR_MAIN_H, VAR_h, VAR_H,
115  VAR_MAIN_W, VAR_w, VAR_W,
116  VAR_MAX_GLYPH_A, VAR_ASCENT,
117  VAR_MAX_GLYPH_D, VAR_DESCENT,
118  VAR_MAX_GLYPH_H,
119  VAR_MAX_GLYPH_W,
120  VAR_N,
121  VAR_SAR,
122  VAR_T,
123  VAR_TEXT_H, VAR_TH,
124  VAR_TEXT_W, VAR_TW,
125  VAR_X,
126  VAR_Y,
127  VAR_PICT_TYPE,
128  VAR_VARS_NB
129 };
130 
131 enum expansion_mode {
132  EXP_NONE,
133  EXP_NORMAL,
134  EXP_STRFTIME,
135 };
136 
137 typedef struct DrawTextContext {
138  const AVClass *class;
139  enum expansion_mode 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
157  int shadowx, shadowy;
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 use_kerning; ///< font kerning is used - true/false
163  int tabsize; ///< tab size
164  int fix_bounds; ///< do we let it go out of frame bounds - t/f
165 
166  FFDrawContext dc;
167  FFDrawColor fontcolor; ///< foreground color
168  FFDrawColor shadowcolor; ///< shadow color
169  FFDrawColor bordercolor; ///< border color
170  FFDrawColor boxcolor; ///< background color
171 
172  FT_Library library; ///< freetype font library handle
173  FT_Face face; ///< freetype font face handle
174  FT_Stroker stroker; ///< freetype stroker handle
175  struct AVTreeNode *glyphs; ///< rendered glyphs, stored using the UTF-32 char code
176  char *x_expr; ///< expression for x position
177  char *y_expr; ///< expression for y position
178  AVExpr *x_pexpr, *y_pexpr; ///< parsed expressions for x and y
179  int64_t basetime; ///< base pts time in the real world for display
180  double var_values[VAR_VARS_NB];
181  AVLFG prng; ///< random
182  char *tc_opt_string; ///< specified timecode option string
183  AVRational tc_rate; ///< frame rate for timecode
184  AVTimecode tc; ///< timecode context
185  int tc24hmax; ///< 1 if timecode is wrapped to 24 hours, 0 otherwise
186  int reload; ///< reload text file for each frame
187  int start_number; ///< starting frame number for n/frame_num var
188 #if CONFIG_LIBFRIBIDI
189  int text_shaping; ///< 1 to shape the text before drawing it
190 #endif
191  AVDictionary *metadata;
192 } DrawTextContext;
193 
194 #define OFFSET(x) offsetof(DrawTextContext, x)
195 #define FLAGS AV_OPT_FLAG_FILTERING_PARAM|AV_OPT_FLAG_VIDEO_PARAM
196 
197 static const AVOption drawtext_options[]= {
198  {"fontfile", "set font file", OFFSET(fontfile), AV_OPT_TYPE_STRING, {.str=NULL}, CHAR_MIN, CHAR_MAX, FLAGS},
199  {"text", "set text", OFFSET(text), AV_OPT_TYPE_STRING, {.str=NULL}, CHAR_MIN, CHAR_MAX, FLAGS},
200  {"textfile", "set text file", OFFSET(textfile), AV_OPT_TYPE_STRING, {.str=NULL}, CHAR_MIN, CHAR_MAX, FLAGS},
201  {"fontcolor", "set foreground color", OFFSET(fontcolor.rgba), AV_OPT_TYPE_COLOR, {.str="black"}, CHAR_MIN, CHAR_MAX, FLAGS},
202  {"fontcolor_expr", "set foreground color expression", OFFSET(fontcolor_expr), AV_OPT_TYPE_STRING, {.str=""}, CHAR_MIN, CHAR_MAX, FLAGS},
203  {"boxcolor", "set box color", OFFSET(boxcolor.rgba), AV_OPT_TYPE_COLOR, {.str="white"}, CHAR_MIN, CHAR_MAX, FLAGS},
204  {"bordercolor", "set border color", OFFSET(bordercolor.rgba), AV_OPT_TYPE_COLOR, {.str="black"}, CHAR_MIN, CHAR_MAX, FLAGS},
205  {"shadowcolor", "set shadow color", OFFSET(shadowcolor.rgba), AV_OPT_TYPE_COLOR, {.str="black"}, CHAR_MIN, CHAR_MAX, FLAGS},
206  {"box", "set box", OFFSET(draw_box), AV_OPT_TYPE_INT, {.i64=0}, 0, 1 , FLAGS},
207  {"fontsize", "set font size", OFFSET(fontsize), AV_OPT_TYPE_INT, {.i64=0}, 0, INT_MAX , FLAGS},
208  {"x", "set x expression", OFFSET(x_expr), AV_OPT_TYPE_STRING, {.str="0"}, CHAR_MIN, CHAR_MAX, FLAGS},
209  {"y", "set y expression", OFFSET(y_expr), AV_OPT_TYPE_STRING, {.str="0"}, CHAR_MIN, CHAR_MAX, FLAGS},
210  {"shadowx", "set x", OFFSET(shadowx), AV_OPT_TYPE_INT, {.i64=0}, INT_MIN, INT_MAX , FLAGS},
211  {"shadowy", "set y", OFFSET(shadowy), AV_OPT_TYPE_INT, {.i64=0}, INT_MIN, INT_MAX , FLAGS},
212  {"borderw", "set border width", OFFSET(borderw), AV_OPT_TYPE_INT, {.i64=0}, INT_MIN, INT_MAX , FLAGS},
213  {"tabsize", "set tab size", OFFSET(tabsize), AV_OPT_TYPE_INT, {.i64=4}, 0, INT_MAX , FLAGS},
214  {"basetime", "set base time", OFFSET(basetime), AV_OPT_TYPE_INT64, {.i64=AV_NOPTS_VALUE}, INT64_MIN, INT64_MAX , FLAGS},
215 #if CONFIG_LIBFONTCONFIG
216  { "font", "Font name", OFFSET(font), AV_OPT_TYPE_STRING, { .str = "Sans" }, .flags = FLAGS },
217 #endif
218 
219  {"expansion", "set the expansion mode", OFFSET(exp_mode), AV_OPT_TYPE_INT, {.i64=EXP_NORMAL}, 0, 2, FLAGS, "expansion"},
220  {"none", "set no expansion", OFFSET(exp_mode), AV_OPT_TYPE_CONST, {.i64=EXP_NONE}, 0, 0, FLAGS, "expansion"},
221  {"normal", "set normal expansion", OFFSET(exp_mode), AV_OPT_TYPE_CONST, {.i64=EXP_NORMAL}, 0, 0, FLAGS, "expansion"},
222  {"strftime", "set strftime expansion (deprecated)", OFFSET(exp_mode), AV_OPT_TYPE_CONST, {.i64=EXP_STRFTIME}, 0, 0, FLAGS, "expansion"},
223 
224  {"timecode", "set initial timecode", OFFSET(tc_opt_string), AV_OPT_TYPE_STRING, {.str=NULL}, CHAR_MIN, CHAR_MAX, FLAGS},
225  {"tc24hmax", "set 24 hours max (timecode only)", OFFSET(tc24hmax), AV_OPT_TYPE_INT, {.i64=0}, 0, 1, FLAGS},
226  {"timecode_rate", "set rate (timecode only)", OFFSET(tc_rate), AV_OPT_TYPE_RATIONAL, {.dbl=0}, 0, INT_MAX, FLAGS},
227  {"r", "set rate (timecode only)", OFFSET(tc_rate), AV_OPT_TYPE_RATIONAL, {.dbl=0}, 0, INT_MAX, FLAGS},
228  {"rate", "set rate (timecode only)", OFFSET(tc_rate), AV_OPT_TYPE_RATIONAL, {.dbl=0}, 0, INT_MAX, FLAGS},
229  {"reload", "reload text file for each frame", OFFSET(reload), AV_OPT_TYPE_INT, {.i64=0}, 0, 1, FLAGS},
230  {"fix_bounds", "if true, check and fix text coords to avoid clipping", OFFSET(fix_bounds), AV_OPT_TYPE_INT, {.i64=1}, 0, 1, FLAGS},
231  {"start_number", "start frame number for n/frame_num variable", OFFSET(start_number), AV_OPT_TYPE_INT, {.i64=0}, 0, INT_MAX, FLAGS},
232 
233 #if CONFIG_LIBFRIBIDI
234  {"text_shaping", "attempt to shape text before drawing", OFFSET(text_shaping), AV_OPT_TYPE_INT, {.i64=1}, 0, 1, FLAGS},
235 #endif
236 
237  /* FT_LOAD_* flags */
238  { "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" },
239  { "default", NULL, 0, AV_OPT_TYPE_CONST, { .i64 = FT_LOAD_DEFAULT }, .flags = FLAGS, .unit = "ft_load_flags" },
240  { "no_scale", NULL, 0, AV_OPT_TYPE_CONST, { .i64 = FT_LOAD_NO_SCALE }, .flags = FLAGS, .unit = "ft_load_flags" },
241  { "no_hinting", NULL, 0, AV_OPT_TYPE_CONST, { .i64 = FT_LOAD_NO_HINTING }, .flags = FLAGS, .unit = "ft_load_flags" },
242  { "render", NULL, 0, AV_OPT_TYPE_CONST, { .i64 = FT_LOAD_RENDER }, .flags = FLAGS, .unit = "ft_load_flags" },
243  { "no_bitmap", NULL, 0, AV_OPT_TYPE_CONST, { .i64 = FT_LOAD_NO_BITMAP }, .flags = FLAGS, .unit = "ft_load_flags" },
244  { "vertical_layout", NULL, 0, AV_OPT_TYPE_CONST, { .i64 = FT_LOAD_VERTICAL_LAYOUT }, .flags = FLAGS, .unit = "ft_load_flags" },
245  { "force_autohint", NULL, 0, AV_OPT_TYPE_CONST, { .i64 = FT_LOAD_FORCE_AUTOHINT }, .flags = FLAGS, .unit = "ft_load_flags" },
246  { "crop_bitmap", NULL, 0, AV_OPT_TYPE_CONST, { .i64 = FT_LOAD_CROP_BITMAP }, .flags = FLAGS, .unit = "ft_load_flags" },
247  { "pedantic", NULL, 0, AV_OPT_TYPE_CONST, { .i64 = FT_LOAD_PEDANTIC }, .flags = FLAGS, .unit = "ft_load_flags" },
248  { "ignore_global_advance_width", NULL, 0, AV_OPT_TYPE_CONST, { .i64 = FT_LOAD_IGNORE_GLOBAL_ADVANCE_WIDTH }, .flags = FLAGS, .unit = "ft_load_flags" },
249  { "no_recurse", NULL, 0, AV_OPT_TYPE_CONST, { .i64 = FT_LOAD_NO_RECURSE }, .flags = FLAGS, .unit = "ft_load_flags" },
250  { "ignore_transform", NULL, 0, AV_OPT_TYPE_CONST, { .i64 = FT_LOAD_IGNORE_TRANSFORM }, .flags = FLAGS, .unit = "ft_load_flags" },
251  { "monochrome", NULL, 0, AV_OPT_TYPE_CONST, { .i64 = FT_LOAD_MONOCHROME }, .flags = FLAGS, .unit = "ft_load_flags" },
252  { "linear_design", NULL, 0, AV_OPT_TYPE_CONST, { .i64 = FT_LOAD_LINEAR_DESIGN }, .flags = FLAGS, .unit = "ft_load_flags" },
253  { "no_autohint", NULL, 0, AV_OPT_TYPE_CONST, { .i64 = FT_LOAD_NO_AUTOHINT }, .flags = FLAGS, .unit = "ft_load_flags" },
254  { NULL }
255 };
256 
257 AVFILTER_DEFINE_CLASS(drawtext);
258 
259 #undef __FTERRORS_H__
260 #define FT_ERROR_START_LIST {
261 #define FT_ERRORDEF(e, v, s) { (e), (s) },
262 #define FT_ERROR_END_LIST { 0, NULL } };
263 
264 static const struct ft_error
265 {
266  int err;
267  const char *err_msg;
268 } ft_errors[] =
269 #include FT_ERRORS_H
270 
271 #define FT_ERRMSG(e) ft_errors[e].err_msg
272 
273 typedef struct Glyph {
274  FT_Glyph glyph;
275  FT_Glyph border_glyph;
276  uint32_t code;
277  FT_Bitmap bitmap; ///< array holding bitmaps of font
278  FT_Bitmap border_bitmap; ///< array holding bitmaps of font border
279  FT_BBox bbox;
280  int advance;
281  int bitmap_left;
282  int bitmap_top;
283 } Glyph;
284 
285 static int glyph_cmp(void *key, const void *b)
286 {
287  const Glyph *a = key, *bb = b;
288  int64_t diff = (int64_t)a->code - (int64_t)bb->code;
289  return diff > 0 ? 1 : diff < 0 ? -1 : 0;
290 }
291 
292 /**
293  * Load glyphs corresponding to the UTF-32 codepoint code.
294  */
295 static int load_glyph(AVFilterContext *ctx, Glyph **glyph_ptr, uint32_t code)
296 {
297  DrawTextContext *s = ctx->priv;
298  FT_BitmapGlyph bitmapglyph;
299  Glyph *glyph;
300  struct AVTreeNode *node = NULL;
301  int ret;
302 
303  /* load glyph into s->face->glyph */
304  if (FT_Load_Char(s->face, code, s->ft_load_flags))
305  return AVERROR(EINVAL);
306 
307  glyph = av_mallocz(sizeof(*glyph));
308  if (!glyph) {
309  ret = AVERROR(ENOMEM);
310  goto error;
311  }
312  glyph->code = code;
313 
314  if (FT_Get_Glyph(s->face->glyph, &glyph->glyph)) {
315  ret = AVERROR(EINVAL);
316  goto error;
317  }
318  if (s->borderw) {
319  glyph->border_glyph = glyph->glyph;
320  if (FT_Glyph_StrokeBorder(&glyph->border_glyph, s->stroker, 0, 0) ||
321  FT_Glyph_To_Bitmap(&glyph->border_glyph, FT_RENDER_MODE_NORMAL, 0, 1)) {
322  ret = AVERROR_EXTERNAL;
323  goto error;
324  }
325  bitmapglyph = (FT_BitmapGlyph) glyph->border_glyph;
326  glyph->border_bitmap = bitmapglyph->bitmap;
327  }
328  if (FT_Glyph_To_Bitmap(&glyph->glyph, FT_RENDER_MODE_NORMAL, 0, 1)) {
329  ret = AVERROR_EXTERNAL;
330  goto error;
331  }
332  bitmapglyph = (FT_BitmapGlyph) glyph->glyph;
333 
334  glyph->bitmap = bitmapglyph->bitmap;
335  glyph->bitmap_left = bitmapglyph->left;
336  glyph->bitmap_top = bitmapglyph->top;
337  glyph->advance = s->face->glyph->advance.x >> 6;
338 
339  /* measure text height to calculate text_height (or the maximum text height) */
340  FT_Glyph_Get_CBox(glyph->glyph, ft_glyph_bbox_pixels, &glyph->bbox);
341 
342  /* cache the newly created glyph */
343  if (!(node = av_tree_node_alloc())) {
344  ret = AVERROR(ENOMEM);
345  goto error;
346  }
347  av_tree_insert(&s->glyphs, glyph, glyph_cmp, &node);
348 
349  if (glyph_ptr)
350  *glyph_ptr = glyph;
351  return 0;
352 
353 error:
354  if (glyph)
355  av_freep(&glyph->glyph);
356 
357  av_freep(&glyph);
358  av_freep(&node);
359  return ret;
360 }
361 
362 static int load_font_file(AVFilterContext *ctx, const char *path, int index)
363 {
364  DrawTextContext *s = ctx->priv;
365  int err;
366 
367  err = FT_New_Face(s->library, path, index, &s->face);
368  if (err) {
369  av_log(ctx, AV_LOG_ERROR, "Could not load font \"%s\": %s\n",
370  s->fontfile, FT_ERRMSG(err));
371  return AVERROR(EINVAL);
372  }
373  return 0;
374 }
375 
376 #if CONFIG_LIBFONTCONFIG
377 static int load_font_fontconfig(AVFilterContext *ctx)
378 {
379  DrawTextContext *s = ctx->priv;
380  FcConfig *fontconfig;
381  FcPattern *pat, *best;
382  FcResult result = FcResultMatch;
383  FcChar8 *filename;
384  int index;
385  double size;
386  int err = AVERROR(ENOENT);
387 
388  fontconfig = FcInitLoadConfigAndFonts();
389  if (!fontconfig) {
390  av_log(ctx, AV_LOG_ERROR, "impossible to init fontconfig\n");
391  return AVERROR_UNKNOWN;
392  }
393  pat = FcNameParse(s->fontfile ? s->fontfile :
394  (uint8_t *)(intptr_t)"default");
395  if (!pat) {
396  av_log(ctx, AV_LOG_ERROR, "could not parse fontconfig pat");
397  return AVERROR(EINVAL);
398  }
399 
400  FcPatternAddString(pat, FC_FAMILY, s->font);
401  if (s->fontsize)
402  FcPatternAddDouble(pat, FC_SIZE, (double)s->fontsize);
403 
404  FcDefaultSubstitute(pat);
405 
406  if (!FcConfigSubstitute(fontconfig, pat, FcMatchPattern)) {
407  av_log(ctx, AV_LOG_ERROR, "could not substitue fontconfig options"); /* very unlikely */
408  FcPatternDestroy(pat);
409  return AVERROR(ENOMEM);
410  }
411 
412  best = FcFontMatch(fontconfig, pat, &result);
413  FcPatternDestroy(pat);
414 
415  if (!best || result != FcResultMatch) {
416  av_log(ctx, AV_LOG_ERROR,
417  "Cannot find a valid font for the family %s\n",
418  s->font);
419  goto fail;
420  }
421 
422  if (
423  FcPatternGetInteger(best, FC_INDEX, 0, &index ) != FcResultMatch ||
424  FcPatternGetDouble (best, FC_SIZE, 0, &size ) != FcResultMatch) {
425  av_log(ctx, AV_LOG_ERROR, "impossible to find font information");
426  return AVERROR(EINVAL);
427  }
428 
429  if (FcPatternGetString(best, FC_FILE, 0, &filename) != FcResultMatch) {
430  av_log(ctx, AV_LOG_ERROR, "No file path for %s\n",
431  s->font);
432  goto fail;
433  }
434 
435  av_log(ctx, AV_LOG_INFO, "Using \"%s\"\n", filename);
436  if (!s->fontsize)
437  s->fontsize = size + 0.5;
438 
439  err = load_font_file(ctx, filename, index);
440  if (err)
441  return err;
442  FcConfigDestroy(fontconfig);
443 fail:
444  FcPatternDestroy(best);
445  return err;
446 }
447 #endif
448 
449 static int load_font(AVFilterContext *ctx)
450 {
451  DrawTextContext *s = ctx->priv;
452  int err;
453 
454  /* load the face, and set up the encoding, which is by default UTF-8 */
455  err = load_font_file(ctx, s->fontfile, 0);
456  if (!err)
457  return 0;
458 #if CONFIG_LIBFONTCONFIG
459  err = load_font_fontconfig(ctx);
460  if (!err)
461  return 0;
462 #endif
463  return err;
464 }
465 
466 static int load_textfile(AVFilterContext *ctx)
467 {
468  DrawTextContext *s = ctx->priv;
469  int err;
470  uint8_t *textbuf;
471  uint8_t *tmp;
472  size_t textbuf_size;
473 
474  if ((err = av_file_map(s->textfile, &textbuf, &textbuf_size, 0, ctx)) < 0) {
475  av_log(ctx, AV_LOG_ERROR,
476  "The text file '%s' could not be read or is empty\n",
477  s->textfile);
478  return err;
479  }
480 
481  if (textbuf_size > SIZE_MAX - 1 || !(tmp = av_realloc(s->text, textbuf_size + 1))) {
482  av_file_unmap(textbuf, textbuf_size);
483  return AVERROR(ENOMEM);
484  }
485  s->text = tmp;
486  memcpy(s->text, textbuf, textbuf_size);
487  s->text[textbuf_size] = 0;
488  av_file_unmap(textbuf, textbuf_size);
489 
490  return 0;
491 }
492 
493 static inline int is_newline(uint32_t c)
494 {
495  return c == '\n' || c == '\r' || c == '\f' || c == '\v';
496 }
497 
498 #if CONFIG_LIBFRIBIDI
499 static int shape_text(AVFilterContext *ctx)
500 {
501  DrawTextContext *s = ctx->priv;
502  uint8_t *tmp;
503  int ret = AVERROR(ENOMEM);
504  static const FriBidiFlags flags = FRIBIDI_FLAGS_DEFAULT |
505  FRIBIDI_FLAGS_ARABIC;
506  FriBidiChar *unicodestr = NULL;
507  FriBidiStrIndex len;
508  FriBidiParType direction = FRIBIDI_PAR_LTR;
509  FriBidiStrIndex line_start = 0;
510  FriBidiStrIndex line_end = 0;
511  FriBidiLevel *embedding_levels = NULL;
512  FriBidiArabicProp *ar_props = NULL;
513  FriBidiCharType *bidi_types = NULL;
514  FriBidiStrIndex i,j;
515 
516  len = strlen(s->text);
517  if (!(unicodestr = av_malloc_array(len, sizeof(*unicodestr)))) {
518  goto out;
519  }
520  len = fribidi_charset_to_unicode(FRIBIDI_CHAR_SET_UTF8,
521  s->text, len, unicodestr);
522 
523  bidi_types = av_malloc_array(len, sizeof(*bidi_types));
524  if (!bidi_types) {
525  goto out;
526  }
527 
528  fribidi_get_bidi_types(unicodestr, len, bidi_types);
529 
530  embedding_levels = av_malloc_array(len, sizeof(*embedding_levels));
531  if (!embedding_levels) {
532  goto out;
533  }
534 
535  if (!fribidi_get_par_embedding_levels(bidi_types, len, &direction,
536  embedding_levels)) {
537  goto out;
538  }
539 
540  ar_props = av_malloc_array(len, sizeof(*ar_props));
541  if (!ar_props) {
542  goto out;
543  }
544 
545  fribidi_get_joining_types(unicodestr, len, ar_props);
546  fribidi_join_arabic(bidi_types, len, embedding_levels, ar_props);
547  fribidi_shape(flags, embedding_levels, len, ar_props, unicodestr);
548 
549  for (line_end = 0, line_start = 0; line_end < len; line_end++) {
550  if (is_newline(unicodestr[line_end]) || line_end == len - 1) {
551  if (!fribidi_reorder_line(flags, bidi_types,
552  line_end - line_start + 1, line_start,
553  direction, embedding_levels, unicodestr,
554  NULL)) {
555  goto out;
556  }
557  line_start = line_end + 1;
558  }
559  }
560 
561  /* Remove zero-width fill chars put in by libfribidi */
562  for (i = 0, j = 0; i < len; i++)
563  if (unicodestr[i] != FRIBIDI_CHAR_FILL)
564  unicodestr[j++] = unicodestr[i];
565  len = j;
566 
567  if (!(tmp = av_realloc(s->text, (len * 4 + 1) * sizeof(*s->text)))) {
568  /* Use len * 4, as a unicode character can be up to 4 bytes in UTF-8 */
569  goto out;
570  }
571 
572  s->text = tmp;
573  len = fribidi_unicode_to_charset(FRIBIDI_CHAR_SET_UTF8,
574  unicodestr, len, s->text);
575  ret = 0;
576 
577 out:
578  av_free(unicodestr);
579  av_free(embedding_levels);
580  av_free(ar_props);
581  av_free(bidi_types);
582  return ret;
583 }
584 #endif
585 
586 static av_cold int init(AVFilterContext *ctx)
587 {
588  int err;
589  DrawTextContext *s = ctx->priv;
590  Glyph *glyph;
591 
592  if (!s->fontfile && !CONFIG_LIBFONTCONFIG) {
593  av_log(ctx, AV_LOG_ERROR, "No font filename provided\n");
594  return AVERROR(EINVAL);
595  }
596 
597  if (s->textfile) {
598  if (s->text) {
599  av_log(ctx, AV_LOG_ERROR,
600  "Both text and text file provided. Please provide only one\n");
601  return AVERROR(EINVAL);
602  }
603  if ((err = load_textfile(ctx)) < 0)
604  return err;
605  }
606 
607 #if CONFIG_LIBFRIBIDI
608  if (s->text_shaping)
609  if ((err = shape_text(ctx)) < 0)
610  return err;
611 #endif
612 
613  if (s->reload && !s->textfile)
614  av_log(ctx, AV_LOG_WARNING, "No file to reload\n");
615 
616  if (s->tc_opt_string) {
617  int ret = av_timecode_init_from_string(&s->tc, s->tc_rate,
618  s->tc_opt_string, ctx);
619  if (ret < 0)
620  return ret;
621  if (s->tc24hmax)
622  s->tc.flags |= AV_TIMECODE_FLAG_24HOURSMAX;
623  if (!s->text)
624  s->text = av_strdup("");
625  }
626 
627  if (!s->text) {
628  av_log(ctx, AV_LOG_ERROR,
629  "Either text, a valid file or a timecode must be provided\n");
630  return AVERROR(EINVAL);
631  }
632 
633  if ((err = FT_Init_FreeType(&(s->library)))) {
634  av_log(ctx, AV_LOG_ERROR,
635  "Could not load FreeType: %s\n", FT_ERRMSG(err));
636  return AVERROR(EINVAL);
637  }
638 
639  err = load_font(ctx);
640  if (err)
641  return err;
642  if (!s->fontsize)
643  s->fontsize = 16;
644  if ((err = FT_Set_Pixel_Sizes(s->face, 0, s->fontsize))) {
645  av_log(ctx, AV_LOG_ERROR, "Could not set font size to %d pixels: %s\n",
646  s->fontsize, FT_ERRMSG(err));
647  return AVERROR(EINVAL);
648  }
649 
650  if (s->borderw) {
651  if (FT_Stroker_New(s->library, &s->stroker)) {
652  av_log(ctx, AV_LOG_ERROR, "Coult not init FT stroker\n");
653  return AVERROR_EXTERNAL;
654  }
655  FT_Stroker_Set(s->stroker, s->borderw << 6, FT_STROKER_LINECAP_ROUND,
656  FT_STROKER_LINEJOIN_ROUND, 0);
657  }
658 
659  s->use_kerning = FT_HAS_KERNING(s->face);
660 
661  /* load the fallback glyph with code 0 */
662  load_glyph(ctx, NULL, 0);
663 
664  /* set the tabsize in pixels */
665  if ((err = load_glyph(ctx, &glyph, ' ')) < 0) {
666  av_log(ctx, AV_LOG_ERROR, "Could not set tabsize.\n");
667  return err;
668  }
669  s->tabsize *= glyph->advance;
670 
671  if (s->exp_mode == EXP_STRFTIME &&
672  (strchr(s->text, '%') || strchr(s->text, '\\')))
673  av_log(ctx, AV_LOG_WARNING, "expansion=strftime is deprecated.\n");
674 
675  av_bprint_init(&s->expanded_text, 0, AV_BPRINT_SIZE_UNLIMITED);
676  av_bprint_init(&s->expanded_fontcolor, 0, AV_BPRINT_SIZE_UNLIMITED);
677 
678  return 0;
679 }
680 
681 static int query_formats(AVFilterContext *ctx)
682 {
683  ff_set_common_formats(ctx, ff_draw_supported_pixel_formats(0));
684  return 0;
685 }
686 
687 static int glyph_enu_free(void *opaque, void *elem)
688 {
689  Glyph *glyph = elem;
690 
691  FT_Done_Glyph(glyph->glyph);
692  FT_Done_Glyph(glyph->border_glyph);
693  av_free(elem);
694  return 0;
695 }
696 
697 static av_cold void uninit(AVFilterContext *ctx)
698 {
699  DrawTextContext *s = ctx->priv;
700 
701  av_expr_free(s->x_pexpr);
702  av_expr_free(s->y_pexpr);
703  s->x_pexpr = s->y_pexpr = NULL;
704  av_freep(&s->positions);
705  s->nb_positions = 0;
706 
707 
708  av_tree_enumerate(s->glyphs, NULL, NULL, glyph_enu_free);
709  av_tree_destroy(s->glyphs);
710  s->glyphs = NULL;
711 
712  FT_Done_Face(s->face);
713  FT_Stroker_Done(s->stroker);
714  FT_Done_FreeType(s->library);
715 
716  av_bprint_finalize(&s->expanded_text, NULL);
717  av_bprint_finalize(&s->expanded_fontcolor, NULL);
718 }
719 
720 static int config_input(AVFilterLink *inlink)
721 {
722  AVFilterContext *ctx = inlink->dst;
723  DrawTextContext *s = ctx->priv;
724  int ret;
725 
726  ff_draw_init(&s->dc, inlink->format, 0);
727  ff_draw_color(&s->dc, &s->fontcolor, s->fontcolor.rgba);
728  ff_draw_color(&s->dc, &s->shadowcolor, s->shadowcolor.rgba);
729  ff_draw_color(&s->dc, &s->bordercolor, s->bordercolor.rgba);
730  ff_draw_color(&s->dc, &s->boxcolor, s->boxcolor.rgba);
731 
732  s->var_values[VAR_w] = s->var_values[VAR_W] = s->var_values[VAR_MAIN_W] = inlink->w;
733  s->var_values[VAR_h] = s->var_values[VAR_H] = s->var_values[VAR_MAIN_H] = inlink->h;
734  s->var_values[VAR_SAR] = inlink->sample_aspect_ratio.num ? av_q2d(inlink->sample_aspect_ratio) : 1;
735  s->var_values[VAR_DAR] = (double)inlink->w / inlink->h * s->var_values[VAR_SAR];
736  s->var_values[VAR_HSUB] = 1 << s->dc.hsub_max;
737  s->var_values[VAR_VSUB] = 1 << s->dc.vsub_max;
738  s->var_values[VAR_X] = NAN;
739  s->var_values[VAR_Y] = NAN;
740  s->var_values[VAR_T] = NAN;
741 
742  av_lfg_init(&s->prng, av_get_random_seed());
743 
744  av_expr_free(s->x_pexpr);
745  av_expr_free(s->y_pexpr);
746  s->x_pexpr = s->y_pexpr = NULL;
747 
748  if ((ret = av_expr_parse(&s->x_pexpr, s->x_expr, var_names,
749  NULL, NULL, fun2_names, fun2, 0, ctx)) < 0 ||
750  (ret = av_expr_parse(&s->y_pexpr, s->y_expr, var_names,
751  NULL, NULL, fun2_names, fun2, 0, ctx)) < 0)
752 
753  return AVERROR(EINVAL);
754 
755  return 0;
756 }
757 
758 static int command(AVFilterContext *ctx, const char *cmd, const char *arg, char *res, int res_len, int flags)
759 {
760  DrawTextContext *s = ctx->priv;
761 
762  if (!strcmp(cmd, "reinit")) {
763  int ret;
764  uninit(ctx);
765  s->reinit = 1;
766  if ((ret = av_set_options_string(ctx, arg, "=", ":")) < 0)
767  return ret;
768  if ((ret = init(ctx)) < 0)
769  return ret;
770  return config_input(ctx->inputs[0]);
771  }
772 
773  return AVERROR(ENOSYS);
774 }
775 
776 static int func_pict_type(AVFilterContext *ctx, AVBPrint *bp,
777  char *fct, unsigned argc, char **argv, int tag)
778 {
779  DrawTextContext *s = ctx->priv;
780 
781  av_bprintf(bp, "%c", av_get_picture_type_char(s->var_values[VAR_PICT_TYPE]));
782  return 0;
783 }
784 
785 static int func_pts(AVFilterContext *ctx, AVBPrint *bp,
786  char *fct, unsigned argc, char **argv, int tag)
787 {
788  DrawTextContext *s = ctx->priv;
789  const char *fmt;
790  double pts = s->var_values[VAR_T];
791  int ret;
792 
793  fmt = argc >= 1 ? argv[0] : "flt";
794  if (argc >= 2) {
795  int64_t delta;
796  if ((ret = av_parse_time(&delta, argv[1], 1)) < 0) {
797  av_log(ctx, AV_LOG_ERROR, "Invalid delta '%s'\n", argv[1]);
798  return ret;
799  }
800  pts += (double)delta / AV_TIME_BASE;
801  }
802  if (!strcmp(fmt, "flt")) {
803  av_bprintf(bp, "%.6f", s->var_values[VAR_T]);
804  } else if (!strcmp(fmt, "hms")) {
805  if (isnan(pts)) {
806  av_bprintf(bp, " ??:??:??.???");
807  } else {
808  int64_t ms = round(pts * 1000);
809  char sign = ' ';
810  if (ms < 0) {
811  sign = '-';
812  ms = -ms;
813  }
814  av_bprintf(bp, "%c%02d:%02d:%02d.%03d", sign,
815  (int)(ms / (60 * 60 * 1000)),
816  (int)(ms / (60 * 1000)) % 60,
817  (int)(ms / 1000) % 60,
818  (int)ms % 1000);
819  }
820  } else {
821  av_log(ctx, AV_LOG_ERROR, "Invalid format '%s'\n", fmt);
822  return AVERROR(EINVAL);
823  }
824  return 0;
825 }
826 
827 static int func_frame_num(AVFilterContext *ctx, AVBPrint *bp,
828  char *fct, unsigned argc, char **argv, int tag)
829 {
830  DrawTextContext *s = ctx->priv;
831 
832  av_bprintf(bp, "%d", (int)s->var_values[VAR_N]);
833  return 0;
834 }
835 
836 static int func_metadata(AVFilterContext *ctx, AVBPrint *bp,
837  char *fct, unsigned argc, char **argv, int tag)
838 {
839  DrawTextContext *s = ctx->priv;
840  AVDictionaryEntry *e = av_dict_get(s->metadata, argv[0], NULL, 0);
841 
842  if (e && e->value)
843  av_bprintf(bp, "%s", e->value);
844  return 0;
845 }
846 
847 static int func_strftime(AVFilterContext *ctx, AVBPrint *bp,
848  char *fct, unsigned argc, char **argv, int tag)
849 {
850  const char *fmt = argc ? argv[0] : "%Y-%m-%d %H:%M:%S";
851  time_t now;
852  struct tm tm;
853 
854  time(&now);
855  if (tag == 'L')
856  localtime_r(&now, &tm);
857  else
858  tm = *gmtime_r(&now, &tm);
859  av_bprint_strftime(bp, fmt, &tm);
860  return 0;
861 }
862 
863 static int func_eval_expr(AVFilterContext *ctx, AVBPrint *bp,
864  char *fct, unsigned argc, char **argv, int tag)
865 {
866  DrawTextContext *s = ctx->priv;
867  double res;
868  int ret;
869 
870  ret = av_expr_parse_and_eval(&res, argv[0], var_names, s->var_values,
871  NULL, NULL, fun2_names, fun2,
872  &s->prng, 0, ctx);
873  if (ret < 0)
874  av_log(ctx, AV_LOG_ERROR,
875  "Expression '%s' for the expr text expansion function is not valid\n",
876  argv[0]);
877  else
878  av_bprintf(bp, "%f", res);
879 
880  return ret;
881 }
882 
883 static int func_eval_expr_int_format(AVFilterContext *ctx, AVBPrint *bp,
884  char *fct, unsigned argc, char **argv, int tag)
885 {
886  DrawTextContext *s = ctx->priv;
887  double res;
888  int intval;
889  int ret;
890  unsigned int positions = 0;
891  char fmt_str[30] = "%";
892 
893  /*
894  * argv[0] expression to be converted to `int`
895  * argv[1] format: 'x', 'X', 'd' or 'u'
896  * argv[2] positions printed (optional)
897  */
898 
899  ret = av_expr_parse_and_eval(&res, argv[0], var_names, s->var_values,
900  NULL, NULL, fun2_names, fun2,
901  &s->prng, 0, ctx);
902  if (ret < 0) {
903  av_log(ctx, AV_LOG_ERROR,
904  "Expression '%s' for the expr text expansion function is not valid\n",
905  argv[0]);
906  return ret;
907  }
908 
909  if (!strchr("xXdu", argv[1][0])) {
910  av_log(ctx, AV_LOG_ERROR, "Invalid format '%c' specified,"
911  " allowed values: 'x', 'X', 'd', 'u'\n", argv[1][0]);
912  return AVERROR(EINVAL);
913  }
914 
915  if (argc == 3) {
916  ret = sscanf(argv[2], "%u", &positions);
917  if (ret != 1) {
918  av_log(ctx, AV_LOG_ERROR, "expr_int_format(): Invalid number of positions"
919  " to print: '%s'\n", argv[2]);
920  return AVERROR(EINVAL);
921  }
922  }
923 
924  feclearexcept(FE_ALL_EXCEPT);
925  intval = res;
926  if ((ret = fetestexcept(FE_INVALID|FE_OVERFLOW|FE_UNDERFLOW))) {
927  av_log(ctx, AV_LOG_ERROR, "Conversion of floating-point result to int failed. Control register: 0x%08x. Conversion result: %d\n", ret, intval);
928  return AVERROR(EINVAL);
929  }
930 
931  if (argc == 3)
932  av_strlcatf(fmt_str, sizeof(fmt_str), "0%u", positions);
933  av_strlcatf(fmt_str, sizeof(fmt_str), "%c", argv[1][0]);
934 
935  av_log(ctx, AV_LOG_DEBUG, "Formatting value %f (expr '%s') with spec '%s'\n",
936  res, argv[0], fmt_str);
937 
938  av_bprintf(bp, fmt_str, intval);
939 
940  return 0;
941 }
942 
943 static const struct drawtext_function {
944  const char *name;
945  unsigned argc_min, argc_max;
946  int tag; /**< opaque argument to func */
947  int (*func)(AVFilterContext *, AVBPrint *, char *, unsigned, char **, int);
948 } functions[] = {
949  { "expr", 1, 1, 0, func_eval_expr },
950  { "e", 1, 1, 0, func_eval_expr },
951  { "expr_int_format", 2, 3, 0, func_eval_expr_int_format },
952  { "eif", 2, 3, 0, func_eval_expr_int_format },
953  { "pict_type", 0, 0, 0, func_pict_type },
954  { "pts", 0, 2, 0, func_pts },
955  { "gmtime", 0, 1, 'G', func_strftime },
956  { "localtime", 0, 1, 'L', func_strftime },
957  { "frame_num", 0, 0, 0, func_frame_num },
958  { "n", 0, 0, 0, func_frame_num },
959  { "metadata", 1, 1, 0, func_metadata },
960 };
961 
962 static int eval_function(AVFilterContext *ctx, AVBPrint *bp, char *fct,
963  unsigned argc, char **argv)
964 {
965  unsigned i;
966 
967  for (i = 0; i < FF_ARRAY_ELEMS(functions); i++) {
968  if (strcmp(fct, functions[i].name))
969  continue;
970  if (argc < functions[i].argc_min) {
971  av_log(ctx, AV_LOG_ERROR, "%%{%s} requires at least %d arguments\n",
972  fct, functions[i].argc_min);
973  return AVERROR(EINVAL);
974  }
975  if (argc > functions[i].argc_max) {
976  av_log(ctx, AV_LOG_ERROR, "%%{%s} requires at most %d arguments\n",
977  fct, functions[i].argc_max);
978  return AVERROR(EINVAL);
979  }
980  break;
981  }
982  if (i >= FF_ARRAY_ELEMS(functions)) {
983  av_log(ctx, AV_LOG_ERROR, "%%{%s} is not known\n", fct);
984  return AVERROR(EINVAL);
985  }
986  return functions[i].func(ctx, bp, fct, argc, argv, functions[i].tag);
987 }
988 
989 static int expand_function(AVFilterContext *ctx, AVBPrint *bp, char **rtext)
990 {
991  const char *text = *rtext;
992  char *argv[16] = { NULL };
993  unsigned argc = 0, i;
994  int ret;
995 
996  if (*text != '{') {
997  av_log(ctx, AV_LOG_ERROR, "Stray %% near '%s'\n", text);
998  return AVERROR(EINVAL);
999  }
1000  text++;
1001  while (1) {
1002  if (!(argv[argc++] = av_get_token(&text, ":}"))) {
1003  ret = AVERROR(ENOMEM);
1004  goto end;
1005  }
1006  if (!*text) {
1007  av_log(ctx, AV_LOG_ERROR, "Unterminated %%{} near '%s'\n", *rtext);
1008  ret = AVERROR(EINVAL);
1009  goto end;
1010  }
1011  if (argc == FF_ARRAY_ELEMS(argv))
1012  av_freep(&argv[--argc]); /* error will be caught later */
1013  if (*text == '}')
1014  break;
1015  text++;
1016  }
1017 
1018  if ((ret = eval_function(ctx, bp, argv[0], argc - 1, argv + 1)) < 0)
1019  goto end;
1020  ret = 0;
1021  *rtext = (char *)text + 1;
1022 
1023 end:
1024  for (i = 0; i < argc; i++)
1025  av_freep(&argv[i]);
1026  return ret;
1027 }
1028 
1029 static int expand_text(AVFilterContext *ctx, char *text, AVBPrint *bp)
1030 {
1031  int ret;
1032 
1033  av_bprint_clear(bp);
1034  while (*text) {
1035  if (*text == '\\' && text[1]) {
1036  av_bprint_chars(bp, text[1], 1);
1037  text += 2;
1038  } else if (*text == '%') {
1039  text++;
1040  if ((ret = expand_function(ctx, bp, &text)) < 0)
1041  return ret;
1042  } else {
1043  av_bprint_chars(bp, *text, 1);
1044  text++;
1045  }
1046  }
1047  if (!av_bprint_is_complete(bp))
1048  return AVERROR(ENOMEM);
1049  return 0;
1050 }
1051 
1052 static int draw_glyphs(DrawTextContext *s, AVFrame *frame,
1053  int width, int height,
1054  FFDrawColor *color, int x, int y, int borderw)
1055 {
1056  char *text = s->expanded_text.str;
1057  uint32_t code = 0;
1058  int i, x1, y1;
1059  uint8_t *p;
1060  Glyph *glyph = NULL;
1061 
1062  for (i = 0, p = text; *p; i++) {
1063  FT_Bitmap bitmap;
1064  Glyph dummy = { 0 };
1065  GET_UTF8(code, *p++, continue;);
1066 
1067  /* skip new line chars, just go to new line */
1068  if (code == '\n' || code == '\r' || code == '\t')
1069  continue;
1070 
1071  dummy.code = code;
1072  glyph = av_tree_find(s->glyphs, &dummy, (void *)glyph_cmp, NULL);
1073 
1074  bitmap = borderw ? glyph->border_bitmap : glyph->bitmap;
1075 
1076  if (glyph->bitmap.pixel_mode != FT_PIXEL_MODE_MONO &&
1077  glyph->bitmap.pixel_mode != FT_PIXEL_MODE_GRAY)
1078  return AVERROR(EINVAL);
1079 
1080  x1 = s->positions[i].x+s->x+x - borderw;
1081  y1 = s->positions[i].y+s->y+y - borderw;
1082 
1083  ff_blend_mask(&s->dc, color,
1084  frame->data, frame->linesize, width, height,
1085  bitmap.buffer, bitmap.pitch,
1086  bitmap.width, bitmap.rows,
1087  bitmap.pixel_mode == FT_PIXEL_MODE_MONO ? 0 : 3,
1088  0, x1, y1);
1089  }
1090 
1091  return 0;
1092 }
1093 
1094 static int draw_text(AVFilterContext *ctx, AVFrame *frame,
1095  int width, int height)
1096 {
1097  DrawTextContext *s = ctx->priv;
1098  AVFilterLink *inlink = ctx->inputs[0];
1099 
1100  uint32_t code = 0, prev_code = 0;
1101  int x = 0, y = 0, i = 0, ret;
1102  int max_text_line_w = 0, len;
1103  int box_w, box_h;
1104  char *text;
1105  uint8_t *p;
1106  int y_min = 32000, y_max = -32000;
1107  int x_min = 32000, x_max = -32000;
1108  FT_Vector delta;
1109  Glyph *glyph = NULL, *prev_glyph = NULL;
1110  Glyph dummy = { 0 };
1111 
1112  time_t now = time(0);
1113  struct tm ltime;
1114  AVBPrint *bp = &s->expanded_text;
1115 
1116  av_bprint_clear(bp);
1117 
1118  if(s->basetime != AV_NOPTS_VALUE)
1119  now= frame->pts*av_q2d(ctx->inputs[0]->time_base) + s->basetime/1000000;
1120 
1121  switch (s->exp_mode) {
1122  case EXP_NONE:
1123  av_bprintf(bp, "%s", s->text);
1124  break;
1125  case EXP_NORMAL:
1126  if ((ret = expand_text(ctx, s->text, &s->expanded_text)) < 0)
1127  return ret;
1128  break;
1129  case EXP_STRFTIME:
1130  localtime_r(&now, &ltime);
1131  av_bprint_strftime(bp, s->text, &ltime);
1132  break;
1133  }
1134 
1135  if (s->tc_opt_string) {
1136  char tcbuf[AV_TIMECODE_STR_SIZE];
1137  av_timecode_make_string(&s->tc, tcbuf, inlink->frame_count);
1138  av_bprint_clear(bp);
1139  av_bprintf(bp, "%s%s", s->text, tcbuf);
1140  }
1141 
1142  if (!av_bprint_is_complete(bp))
1143  return AVERROR(ENOMEM);
1144  text = s->expanded_text.str;
1145  if ((len = s->expanded_text.len) > s->nb_positions) {
1146  if (!(s->positions =
1147  av_realloc(s->positions, len*sizeof(*s->positions))))
1148  return AVERROR(ENOMEM);
1149  s->nb_positions = len;
1150  }
1151 
1152  if (s->fontcolor_expr[0]) {
1153  /* If expression is set, evaluate and replace the static value */
1154  av_bprint_clear(&s->expanded_fontcolor);
1155  if ((ret = expand_text(ctx, s->fontcolor_expr, &s->expanded_fontcolor)) < 0)
1156  return ret;
1157  if (!av_bprint_is_complete(&s->expanded_fontcolor))
1158  return AVERROR(ENOMEM);
1159  av_log(s, AV_LOG_DEBUG, "Evaluated fontcolor is '%s'\n", s->expanded_fontcolor.str);
1160  ret = av_parse_color(s->fontcolor.rgba, s->expanded_fontcolor.str, -1, s);
1161  if (ret)
1162  return ret;
1163  ff_draw_color(&s->dc, &s->fontcolor, s->fontcolor.rgba);
1164  }
1165 
1166  x = 0;
1167  y = 0;
1168 
1169  /* load and cache glyphs */
1170  for (i = 0, p = text; *p; i++) {
1171  GET_UTF8(code, *p++, continue;);
1172 
1173  /* get glyph */
1174  dummy.code = code;
1175  glyph = av_tree_find(s->glyphs, &dummy, glyph_cmp, NULL);
1176  if (!glyph) {
1177  load_glyph(ctx, &glyph, code);
1178  }
1179 
1180  y_min = FFMIN(glyph->bbox.yMin, y_min);
1181  y_max = FFMAX(glyph->bbox.yMax, y_max);
1182  x_min = FFMIN(glyph->bbox.xMin, x_min);
1183  x_max = FFMAX(glyph->bbox.xMax, x_max);
1184  }
1185  s->max_glyph_h = y_max - y_min;
1186  s->max_glyph_w = x_max - x_min;
1187 
1188  /* compute and save position for each glyph */
1189  glyph = NULL;
1190  for (i = 0, p = text; *p; i++) {
1191  GET_UTF8(code, *p++, continue;);
1192 
1193  /* skip the \n in the sequence \r\n */
1194  if (prev_code == '\r' && code == '\n')
1195  continue;
1196 
1197  prev_code = code;
1198  if (is_newline(code)) {
1199 
1200  max_text_line_w = FFMAX(max_text_line_w, x);
1201  y += s->max_glyph_h;
1202  x = 0;
1203  continue;
1204  }
1205 
1206  /* get glyph */
1207  prev_glyph = glyph;
1208  dummy.code = code;
1209  glyph = av_tree_find(s->glyphs, &dummy, glyph_cmp, NULL);
1210 
1211  /* kerning */
1212  if (s->use_kerning && prev_glyph && glyph->code) {
1213  FT_Get_Kerning(s->face, prev_glyph->code, glyph->code,
1214  ft_kerning_default, &delta);
1215  x += delta.x >> 6;
1216  }
1217 
1218  /* save position */
1219  s->positions[i].x = x + glyph->bitmap_left;
1220  s->positions[i].y = y - glyph->bitmap_top + y_max;
1221  if (code == '\t') x = (x / s->tabsize + 1)*s->tabsize;
1222  else x += glyph->advance;
1223  }
1224 
1225  max_text_line_w = FFMAX(x, max_text_line_w);
1226 
1227  s->var_values[VAR_TW] = s->var_values[VAR_TEXT_W] = max_text_line_w;
1228  s->var_values[VAR_TH] = s->var_values[VAR_TEXT_H] = y + s->max_glyph_h;
1229 
1230  s->var_values[VAR_MAX_GLYPH_W] = s->max_glyph_w;
1231  s->var_values[VAR_MAX_GLYPH_H] = s->max_glyph_h;
1232  s->var_values[VAR_MAX_GLYPH_A] = s->var_values[VAR_ASCENT ] = y_max;
1233  s->var_values[VAR_MAX_GLYPH_D] = s->var_values[VAR_DESCENT] = y_min;
1234 
1235  s->var_values[VAR_LINE_H] = s->var_values[VAR_LH] = s->max_glyph_h;
1236 
1237  s->x = s->var_values[VAR_X] = av_expr_eval(s->x_pexpr, s->var_values, &s->prng);
1238  s->y = s->var_values[VAR_Y] = av_expr_eval(s->y_pexpr, s->var_values, &s->prng);
1239  s->x = s->var_values[VAR_X] = av_expr_eval(s->x_pexpr, s->var_values, &s->prng);
1240 
1241  box_w = FFMIN(width - 1 , max_text_line_w);
1242  box_h = FFMIN(height - 1, y + s->max_glyph_h);
1243 
1244  /* draw box */
1245  if (s->draw_box)
1246  ff_blend_rectangle(&s->dc, &s->boxcolor,
1247  frame->data, frame->linesize, width, height,
1248  s->x, s->y, box_w, box_h);
1249 
1250  if (s->shadowx || s->shadowy) {
1251  if ((ret = draw_glyphs(s, frame, width, height,
1252  &s->shadowcolor, s->shadowx, s->shadowy, 0)) < 0)
1253  return ret;
1254  }
1255 
1256  if (s->borderw) {
1257  if ((ret = draw_glyphs(s, frame, width, height,
1258  &s->bordercolor, 0, 0, s->borderw)) < 0)
1259  return ret;
1260  }
1261  if ((ret = draw_glyphs(s, frame, width, height,
1262  &s->fontcolor, 0, 0, 0)) < 0)
1263  return ret;
1264 
1265  return 0;
1266 }
1267 
1268 static int filter_frame(AVFilterLink *inlink, AVFrame *frame)
1269 {
1270  AVFilterContext *ctx = inlink->dst;
1271  AVFilterLink *outlink = ctx->outputs[0];
1272  DrawTextContext *s = ctx->priv;
1273  int ret;
1274 
1275  if (s->reload) {
1276  if ((ret = load_textfile(ctx)) < 0)
1277  return ret;
1278 #if CONFIG_LIBFRIBIDI
1279  if (s->text_shaping)
1280  if ((ret = shape_text(ctx)) < 0)
1281  return ret;
1282 #endif
1283  }
1284 
1285  s->var_values[VAR_N] = inlink->frame_count+s->start_number;
1286  s->var_values[VAR_T] = frame->pts == AV_NOPTS_VALUE ?
1287  NAN : frame->pts * av_q2d(inlink->time_base);
1288 
1289  s->var_values[VAR_PICT_TYPE] = frame->pict_type;
1290  s->metadata = av_frame_get_metadata(frame);
1291 
1292  draw_text(ctx, frame, frame->width, frame->height);
1293 
1294  av_log(ctx, AV_LOG_DEBUG, "n:%d t:%f text_w:%d text_h:%d x:%d y:%d\n",
1295  (int)s->var_values[VAR_N], s->var_values[VAR_T],
1296  (int)s->var_values[VAR_TEXT_W], (int)s->var_values[VAR_TEXT_H],
1297  s->x, s->y);
1298 
1299  return ff_filter_frame(outlink, frame);
1300 }
1301 
1302 static const AVFilterPad avfilter_vf_drawtext_inputs[] = {
1303  {
1304  .name = "default",
1305  .type = AVMEDIA_TYPE_VIDEO,
1306  .filter_frame = filter_frame,
1307  .config_props = config_input,
1308  .needs_writable = 1,
1309  },
1310  { NULL }
1311 };
1312 
1313 static const AVFilterPad avfilter_vf_drawtext_outputs[] = {
1314  {
1315  .name = "default",
1316  .type = AVMEDIA_TYPE_VIDEO,
1317  },
1318  { NULL }
1319 };
1320 
1321 AVFilter ff_vf_drawtext = {
1322  .name = "drawtext",
1323  .description = NULL_IF_CONFIG_SMALL("Draw text on top of video frames using libfreetype library."),
1324  .priv_size = sizeof(DrawTextContext),
1325  .priv_class = &drawtext_class,
1326  .init = init,
1327  .uninit = uninit,
1328  .query_formats = query_formats,
1329  .inputs = avfilter_vf_drawtext_inputs,
1330  .outputs = avfilter_vf_drawtext_outputs,
1331  .process_command = command,
1332  .flags = AVFILTER_FLAG_SUPPORT_TIMELINE_GENERIC,
1333 };
Generated on Sun Mar 8 2015 02:35:06 for FFmpeg by   doxygen 1.8.2