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>
6 * This file is part of FFmpeg.
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.
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.
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
25 * drawtext filter, based on the original vhook/drawtext.c
26 * filter by Gustavo Sverzut Barbieri
33 #include "libavutil/avstring.h"
34 #include "libavutil/file.h"
35 #include "libavutil/eval.h"
36 #include "libavutil/opt.h"
37 #include "libavutil/random_seed.h"
38 #include "libavutil/parseutils.h"
39 #include "libavutil/timecode.h"
40 #include "libavutil/tree.h"
41 #include "libavutil/lfg.h"
43 #include "drawutils.h"
51 #include <freetype/config/ftheader.h>
52 #include FT_FREETYPE_H
55 #include <fontconfig/fontconfig.h>
58 static const char *const var_names[] = {
61 "line_h", "lh", ///< line height, same as max_glyph_h
62 "main_h", "h", "H", ///< height of the input video
63 "main_w", "w", "W", ///< width of the input video
64 "max_glyph_a", "ascent", ///< max glyph ascent
65 "max_glyph_d", "descent", ///< min glyph descent
66 "max_glyph_h", ///< max glyph height
67 "max_glyph_w", ///< max glyph width
68 "n", ///< number of frame
70 "t", ///< timestamp expressed in seconds
71 "text_h", "th", ///< height of the rendered text
72 "text_w", "tw", ///< width of the rendered text
78 static const char *const fun2_names[] = {
82 static double drand(void *opaque, double min, double max)
84 return min + (max-min) / UINT_MAX * av_lfg_get(opaque);
87 typedef double (*eval_func2)(void *, double a, double b);
89 static const eval_func2 fun2[] = {
98 VAR_MAIN_H, VAR_h, VAR_H,
99 VAR_MAIN_W, VAR_w, VAR_W,
100 VAR_MAX_GLYPH_A, VAR_ASCENT,
101 VAR_MAX_GLYPH_D, VAR_DESCENT,
115 const AVClass *class;
116 int reinit; ///< tells if the filter is being reinited
117 uint8_t *fontfile; ///< font to be used
118 uint8_t *text; ///< text to be drawn
119 uint8_t *expanded_text; ///< used to contain the strftime()-expanded text
120 size_t expanded_text_size; ///< size in bytes of the expanded_text buffer
121 int ft_load_flags; ///< flags used for loading fonts, see FT_LOAD_*
122 FT_Vector *positions; ///< positions for each element in the text
123 size_t nb_positions; ///< number of elements of positions array
124 char *textfile; ///< file with text to be drawn
125 int x; ///< x position to start drawing text
126 int y; ///< y position to start drawing text
127 int max_glyph_w; ///< max glyph width
128 int max_glyph_h; ///< max glyph height
129 int shadowx, shadowy;
130 unsigned int fontsize; ///< font size to use
131 char *fontcolor_string; ///< font color as string
132 char *boxcolor_string; ///< box color as string
133 char *shadowcolor_string; ///< shadow color as string
135 short int draw_box; ///< draw box around text - true or false
136 int use_kerning; ///< font kerning is used - true/false
137 int tabsize; ///< tab size
138 int fix_bounds; ///< do we let it go out of frame bounds - t/f
141 FFDrawColor fontcolor; ///< foreground color
142 FFDrawColor shadowcolor; ///< shadow color
143 FFDrawColor boxcolor; ///< background color
145 FT_Library library; ///< freetype font library handle
146 FT_Face face; ///< freetype font face handle
147 struct AVTreeNode *glyphs; ///< rendered glyphs, stored using the UTF-32 char code
148 char *x_expr; ///< expression for x position
149 char *y_expr; ///< expression for y position
150 AVExpr *x_pexpr, *y_pexpr; ///< parsed expressions for x and y
151 int64_t basetime; ///< base pts time in the real world for display
152 double var_values[VAR_VARS_NB];
153 char *draw_expr; ///< expression for draw
154 AVExpr *draw_pexpr; ///< parsed expression for draw
155 int draw; ///< set to zero to prevent drawing
156 AVLFG prng; ///< random
157 char *tc_opt_string; ///< specified timecode option string
158 AVRational tc_rate; ///< frame rate for timecode
159 AVTimecode tc; ///< timecode context
160 int tc24hmax; ///< 1 if timecode is wrapped to 24 hours, 0 otherwise
164 #define OFFSET(x) offsetof(DrawTextContext, x)
166 static const AVOption drawtext_options[]= {
167 {"fontfile", "set font file", OFFSET(fontfile), AV_OPT_TYPE_STRING, {.str=NULL}, CHAR_MIN, CHAR_MAX },
168 {"text", "set text", OFFSET(text), AV_OPT_TYPE_STRING, {.str=NULL}, CHAR_MIN, CHAR_MAX },
169 {"textfile", "set text file", OFFSET(textfile), AV_OPT_TYPE_STRING, {.str=NULL}, CHAR_MIN, CHAR_MAX },
170 {"fontcolor", "set foreground color", OFFSET(fontcolor_string), AV_OPT_TYPE_STRING, {.str="black"}, CHAR_MIN, CHAR_MAX },
171 {"boxcolor", "set box color", OFFSET(boxcolor_string), AV_OPT_TYPE_STRING, {.str="white"}, CHAR_MIN, CHAR_MAX },
172 {"shadowcolor", "set shadow color", OFFSET(shadowcolor_string), AV_OPT_TYPE_STRING, {.str="black"}, CHAR_MIN, CHAR_MAX },
173 {"box", "set box", OFFSET(draw_box), AV_OPT_TYPE_INT, {.dbl=0}, 0, 1 },
174 {"fontsize", "set font size", OFFSET(fontsize), AV_OPT_TYPE_INT, {.dbl=0}, 0, INT_MAX },
175 {"x", "set x expression", OFFSET(x_expr), AV_OPT_TYPE_STRING, {.str="0"}, CHAR_MIN, CHAR_MAX },
176 {"y", "set y expression", OFFSET(y_expr), AV_OPT_TYPE_STRING, {.str="0"}, CHAR_MIN, CHAR_MAX },
177 {"shadowx", "set x", OFFSET(shadowx), AV_OPT_TYPE_INT, {.dbl=0}, INT_MIN, INT_MAX },
178 {"shadowy", "set y", OFFSET(shadowy), AV_OPT_TYPE_INT, {.dbl=0}, INT_MIN, INT_MAX },
179 {"tabsize", "set tab size", OFFSET(tabsize), AV_OPT_TYPE_INT, {.dbl=4}, 0, INT_MAX },
180 {"basetime", "set base time", OFFSET(basetime), AV_OPT_TYPE_INT64, {.dbl=AV_NOPTS_VALUE}, INT64_MIN, INT64_MAX },
181 {"draw", "if false do not draw", OFFSET(draw_expr), AV_OPT_TYPE_STRING, {.str="1"}, CHAR_MIN, CHAR_MAX },
182 {"timecode", "set initial timecode", OFFSET(tc_opt_string), AV_OPT_TYPE_STRING, {.str=NULL}, CHAR_MIN, CHAR_MAX },
183 {"tc24hmax", "set 24 hours max (timecode only)", OFFSET(tc24hmax), AV_OPT_TYPE_INT, {.dbl=0}, 0, 1 },
184 {"timecode_rate", "set rate (timecode only)", OFFSET(tc_rate), AV_OPT_TYPE_RATIONAL, {.dbl=0}, 0, INT_MAX },
185 {"r", "set rate (timecode only)", OFFSET(tc_rate), AV_OPT_TYPE_RATIONAL, {.dbl=0}, 0, INT_MAX },
186 {"rate", "set rate (timecode only)", OFFSET(tc_rate), AV_OPT_TYPE_RATIONAL, {.dbl=0}, 0, INT_MAX },
187 {"fix_bounds", "if true, check and fix text coords to avoid clipping",
188 OFFSET(fix_bounds), AV_OPT_TYPE_INT, {.dbl=1}, 0, 1 },
190 /* FT_LOAD_* flags */
191 {"ft_load_flags", "set font loading flags for libfreetype", OFFSET(ft_load_flags), AV_OPT_TYPE_FLAGS, {.dbl=FT_LOAD_DEFAULT|FT_LOAD_RENDER}, 0, INT_MAX, 0, "ft_load_flags" },
192 {"default", "set default", 0, AV_OPT_TYPE_CONST, {.dbl=FT_LOAD_DEFAULT}, INT_MIN, INT_MAX, 0, "ft_load_flags" },
193 {"no_scale", "set no_scale", 0, AV_OPT_TYPE_CONST, {.dbl=FT_LOAD_NO_SCALE}, INT_MIN, INT_MAX, 0, "ft_load_flags" },
194 {"no_hinting", "set no_hinting", 0, AV_OPT_TYPE_CONST, {.dbl=FT_LOAD_NO_HINTING}, INT_MIN, INT_MAX, 0, "ft_load_flags" },
195 {"render", "set render", 0, AV_OPT_TYPE_CONST, {.dbl=FT_LOAD_RENDER}, INT_MIN, INT_MAX, 0, "ft_load_flags" },
196 {"no_bitmap", "set no_bitmap", 0, AV_OPT_TYPE_CONST, {.dbl=FT_LOAD_NO_BITMAP}, INT_MIN, INT_MAX, 0, "ft_load_flags" },
197 {"vertical_layout", "set vertical_layout", 0, AV_OPT_TYPE_CONST, {.dbl=FT_LOAD_VERTICAL_LAYOUT}, INT_MIN, INT_MAX, 0, "ft_load_flags" },
198 {"force_autohint", "set force_autohint", 0, AV_OPT_TYPE_CONST, {.dbl=FT_LOAD_FORCE_AUTOHINT}, INT_MIN, INT_MAX, 0, "ft_load_flags" },
199 {"crop_bitmap", "set crop_bitmap", 0, AV_OPT_TYPE_CONST, {.dbl=FT_LOAD_CROP_BITMAP}, INT_MIN, INT_MAX, 0, "ft_load_flags" },
200 {"pedantic", "set pedantic", 0, AV_OPT_TYPE_CONST, {.dbl=FT_LOAD_PEDANTIC}, INT_MIN, INT_MAX, 0, "ft_load_flags" },
201 {"ignore_global_advance_width", "set ignore_global_advance_width", 0, AV_OPT_TYPE_CONST, {.dbl=FT_LOAD_IGNORE_GLOBAL_ADVANCE_WIDTH}, INT_MIN, INT_MAX, 0, "ft_load_flags" },
202 {"no_recurse", "set no_recurse", 0, AV_OPT_TYPE_CONST, {.dbl=FT_LOAD_NO_RECURSE}, INT_MIN, INT_MAX, 0, "ft_load_flags" },
203 {"ignore_transform", "set ignore_transform", 0, AV_OPT_TYPE_CONST, {.dbl=FT_LOAD_IGNORE_TRANSFORM}, INT_MIN, INT_MAX, 0, "ft_load_flags" },
204 {"monochrome", "set monochrome", 0, AV_OPT_TYPE_CONST, {.dbl=FT_LOAD_MONOCHROME}, INT_MIN, INT_MAX, 0, "ft_load_flags" },
205 {"linear_design", "set linear_design", 0, AV_OPT_TYPE_CONST, {.dbl=FT_LOAD_LINEAR_DESIGN}, INT_MIN, INT_MAX, 0, "ft_load_flags" },
206 {"no_autohint", "set no_autohint", 0, AV_OPT_TYPE_CONST, {.dbl=FT_LOAD_NO_AUTOHINT}, INT_MIN, INT_MAX, 0, "ft_load_flags" },
210 static const AVClass drawtext_class = {
211 .class_name = "drawtext",
212 .item_name = av_default_item_name,
213 .option = drawtext_options,
214 .version = LIBAVUTIL_VERSION_INT,
215 .category = AV_CLASS_CATEGORY_FILTER,
218 #undef __FTERRORS_H__
219 #define FT_ERROR_START_LIST {
220 #define FT_ERRORDEF(e, v, s) { (e), (s) },
221 #define FT_ERROR_END_LIST { 0, NULL } };
227 } static ft_errors[] =
230 #define FT_ERRMSG(e) ft_errors[e].err_msg
235 FT_Bitmap bitmap; ///< array holding bitmaps of font
242 static int glyph_cmp(void *key, const void *b)
244 const Glyph *a = key, *bb = b;
245 int64_t diff = (int64_t)a->code - (int64_t)bb->code;
246 return diff > 0 ? 1 : diff < 0 ? -1 : 0;
250 * Load glyphs corresponding to the UTF-32 codepoint code.
252 static int load_glyph(AVFilterContext *ctx, Glyph **glyph_ptr, uint32_t code)
254 DrawTextContext *dtext = ctx->priv;
256 struct AVTreeNode *node = NULL;
259 /* load glyph into dtext->face->glyph */
260 if (FT_Load_Char(dtext->face, code, dtext->ft_load_flags))
261 return AVERROR(EINVAL);
264 if (!(glyph = av_mallocz(sizeof(*glyph))) ||
265 !(glyph->glyph = av_mallocz(sizeof(*glyph->glyph)))) {
266 ret = AVERROR(ENOMEM);
271 if (FT_Get_Glyph(dtext->face->glyph, glyph->glyph)) {
272 ret = AVERROR(EINVAL);
276 glyph->bitmap = dtext->face->glyph->bitmap;
277 glyph->bitmap_left = dtext->face->glyph->bitmap_left;
278 glyph->bitmap_top = dtext->face->glyph->bitmap_top;
279 glyph->advance = dtext->face->glyph->advance.x >> 6;
281 /* measure text height to calculate text_height (or the maximum text height) */
282 FT_Glyph_Get_CBox(*glyph->glyph, ft_glyph_bbox_pixels, &glyph->bbox);
284 /* cache the newly created glyph */
285 if (!(node = av_mallocz(av_tree_node_size))) {
286 ret = AVERROR(ENOMEM);
289 av_tree_insert(&dtext->glyphs, glyph, glyph_cmp, &node);
297 av_freep(&glyph->glyph);
303 static int load_font_file(AVFilterContext *ctx, const char *path, int index,
306 DrawTextContext *dtext = ctx->priv;
309 err = FT_New_Face(dtext->library, path, index, &dtext->face);
311 *error = FT_ERRMSG(err);
312 return AVERROR(EINVAL);
317 #if CONFIG_FONTCONFIG
318 static int load_font_fontconfig(AVFilterContext *ctx, const char **error)
320 DrawTextContext *dtext = ctx->priv;
321 FcConfig *fontconfig;
322 FcPattern *pattern, *fpat;
323 FcResult result = FcResultMatch;
328 fontconfig = FcInitLoadConfigAndFonts();
330 *error = "impossible to init fontconfig\n";
331 return AVERROR(EINVAL);
333 pattern = FcNameParse(dtext->fontfile ? dtext->fontfile :
334 (uint8_t *)(intptr_t)"default");
336 *error = "could not parse fontconfig pattern";
337 return AVERROR(EINVAL);
339 if (!FcConfigSubstitute(fontconfig, pattern, FcMatchPattern)) {
340 *error = "could not substitue fontconfig options"; /* very unlikely */
341 return AVERROR(EINVAL);
343 FcDefaultSubstitute(pattern);
344 fpat = FcFontMatch(fontconfig, pattern, &result);
345 if (!fpat || result != FcResultMatch) {
346 *error = "impossible to find a matching font";
347 return AVERROR(EINVAL);
349 if (FcPatternGetString (fpat, FC_FILE, 0, &filename) != FcResultMatch ||
350 FcPatternGetInteger(fpat, FC_INDEX, 0, &index ) != FcResultMatch ||
351 FcPatternGetDouble (fpat, FC_SIZE, 0, &size ) != FcResultMatch) {
352 *error = "impossible to find font information";
353 return AVERROR(EINVAL);
355 av_log(ctx, AV_LOG_INFO, "Using \"%s\"\n", filename);
356 if (!dtext->fontsize)
357 dtext->fontsize = size + 0.5;
358 err = load_font_file(ctx, filename, index, error);
361 FcPatternDestroy(fpat);
362 FcPatternDestroy(pattern);
363 FcConfigDestroy(fontconfig);
368 static int load_font(AVFilterContext *ctx)
370 DrawTextContext *dtext = ctx->priv;
372 const char *error = "unknown error\n";
374 /* load the face, and set up the encoding, which is by default UTF-8 */
375 err = load_font_file(ctx, dtext->fontfile, 0, &error);
378 #if CONFIG_FONTCONFIG
379 err = load_font_fontconfig(ctx, &error);
383 av_log(ctx, AV_LOG_ERROR, "Could not load font \"%s\": %s\n",
384 dtext->fontfile, error);
388 static av_cold int init(AVFilterContext *ctx, const char *args, void *opaque)
391 DrawTextContext *dtext = ctx->priv;
394 dtext->class = &drawtext_class;
395 av_opt_set_defaults(dtext);
397 if ((err = (av_set_options_string(dtext, args, "=", ":"))) < 0) {
398 av_log(ctx, AV_LOG_ERROR, "Error parsing options string: '%s'\n", args);
402 if (!dtext->fontfile && !CONFIG_FONTCONFIG) {
403 av_log(ctx, AV_LOG_ERROR, "No font filename provided\n");
404 return AVERROR(EINVAL);
407 if (dtext->textfile) {
412 av_log(ctx, AV_LOG_ERROR,
413 "Both text and text file provided. Please provide only one\n");
414 return AVERROR(EINVAL);
416 if ((err = av_file_map(dtext->textfile, &textbuf, &textbuf_size, 0, ctx)) < 0) {
417 av_log(ctx, AV_LOG_ERROR,
418 "The text file '%s' could not be read or is empty\n",
423 if (!(dtext->text = av_malloc(textbuf_size+1)))
424 return AVERROR(ENOMEM);
425 memcpy(dtext->text, textbuf, textbuf_size);
426 dtext->text[textbuf_size] = 0;
427 av_file_unmap(textbuf, textbuf_size);
430 if (dtext->tc_opt_string) {
431 int ret = av_timecode_init_from_string(&dtext->tc, dtext->tc_rate,
432 dtext->tc_opt_string, ctx);
436 dtext->tc.flags |= AV_TIMECODE_FLAG_24HOURSMAX;
438 dtext->text = av_strdup("");
442 av_log(ctx, AV_LOG_ERROR,
443 "Either text, a valid file or a timecode must be provided\n");
444 return AVERROR(EINVAL);
447 if ((err = av_parse_color(dtext->fontcolor.rgba, dtext->fontcolor_string, -1, ctx))) {
448 av_log(ctx, AV_LOG_ERROR,
449 "Invalid font color '%s'\n", dtext->fontcolor_string);
453 if ((err = av_parse_color(dtext->boxcolor.rgba, dtext->boxcolor_string, -1, ctx))) {
454 av_log(ctx, AV_LOG_ERROR,
455 "Invalid box color '%s'\n", dtext->boxcolor_string);
459 if ((err = av_parse_color(dtext->shadowcolor.rgba, dtext->shadowcolor_string, -1, ctx))) {
460 av_log(ctx, AV_LOG_ERROR,
461 "Invalid shadow color '%s'\n", dtext->shadowcolor_string);
465 if ((err = FT_Init_FreeType(&(dtext->library)))) {
466 av_log(ctx, AV_LOG_ERROR,
467 "Could not load FreeType: %s\n", FT_ERRMSG(err));
468 return AVERROR(EINVAL);
471 err = load_font(ctx);
474 if (!dtext->fontsize)
475 dtext->fontsize = 16;
476 if ((err = FT_Set_Pixel_Sizes(dtext->face, 0, dtext->fontsize))) {
477 av_log(ctx, AV_LOG_ERROR, "Could not set font size to %d pixels: %s\n",
478 dtext->fontsize, FT_ERRMSG(err));
479 return AVERROR(EINVAL);
482 dtext->use_kerning = FT_HAS_KERNING(dtext->face);
484 /* load the fallback glyph with code 0 */
485 load_glyph(ctx, NULL, 0);
487 /* set the tabsize in pixels */
488 if ((err = load_glyph(ctx, &glyph, ' ')) < 0) {
489 av_log(ctx, AV_LOG_ERROR, "Could not set tabsize.\n");
492 dtext->tabsize *= glyph->advance;
497 static int query_formats(AVFilterContext *ctx)
499 ff_set_common_formats(ctx, ff_draw_supported_pixel_formats(0));
503 static int glyph_enu_free(void *opaque, void *elem)
507 FT_Done_Glyph(*glyph->glyph);
508 av_freep(&glyph->glyph);
513 static av_cold void uninit(AVFilterContext *ctx)
515 DrawTextContext *dtext = ctx->priv;
517 av_expr_free(dtext->x_pexpr); dtext->x_pexpr = NULL;
518 av_expr_free(dtext->y_pexpr); dtext->y_pexpr = NULL;
519 av_expr_free(dtext->draw_pexpr); dtext->draw_pexpr = NULL;
521 av_freep(&dtext->boxcolor_string);
522 av_freep(&dtext->expanded_text);
523 av_freep(&dtext->fontcolor_string);
524 av_freep(&dtext->fontfile);
525 av_freep(&dtext->shadowcolor_string);
526 av_freep(&dtext->text);
527 av_freep(&dtext->x_expr);
528 av_freep(&dtext->y_expr);
529 av_freep(&dtext->draw_expr);
531 av_freep(&dtext->positions);
532 dtext->nb_positions = 0;
534 av_tree_enumerate(dtext->glyphs, NULL, NULL, glyph_enu_free);
535 av_tree_destroy(dtext->glyphs);
536 dtext->glyphs = NULL;
538 FT_Done_Face(dtext->face);
539 FT_Done_FreeType(dtext->library);
542 static inline int is_newline(uint32_t c)
544 return c == '\n' || c == '\r' || c == '\f' || c == '\v';
547 static int config_input(AVFilterLink *inlink)
549 AVFilterContext *ctx = inlink->dst;
550 DrawTextContext *dtext = ctx->priv;
553 ff_draw_init(&dtext->dc, inlink->format, 0);
554 ff_draw_color(&dtext->dc, &dtext->fontcolor, dtext->fontcolor.rgba);
555 ff_draw_color(&dtext->dc, &dtext->shadowcolor, dtext->shadowcolor.rgba);
556 ff_draw_color(&dtext->dc, &dtext->boxcolor, dtext->boxcolor.rgba);
558 dtext->var_values[VAR_w] = dtext->var_values[VAR_W] = dtext->var_values[VAR_MAIN_W] = inlink->w;
559 dtext->var_values[VAR_h] = dtext->var_values[VAR_H] = dtext->var_values[VAR_MAIN_H] = inlink->h;
560 dtext->var_values[VAR_SAR] = inlink->sample_aspect_ratio.num ? av_q2d(inlink->sample_aspect_ratio) : 1;
561 dtext->var_values[VAR_DAR] = (double)inlink->w / inlink->h * dtext->var_values[VAR_SAR];
562 dtext->var_values[VAR_HSUB] = 1 << dtext->dc.hsub_max;
563 dtext->var_values[VAR_VSUB] = 1 << dtext->dc.vsub_max;
564 dtext->var_values[VAR_X] = NAN;
565 dtext->var_values[VAR_Y] = NAN;
567 dtext->var_values[VAR_N] = 0;
568 dtext->var_values[VAR_T] = NAN;
570 av_lfg_init(&dtext->prng, av_get_random_seed());
572 if ((ret = av_expr_parse(&dtext->x_pexpr, dtext->x_expr, var_names,
573 NULL, NULL, fun2_names, fun2, 0, ctx)) < 0 ||
574 (ret = av_expr_parse(&dtext->y_pexpr, dtext->y_expr, var_names,
575 NULL, NULL, fun2_names, fun2, 0, ctx)) < 0 ||
576 (ret = av_expr_parse(&dtext->draw_pexpr, dtext->draw_expr, var_names,
577 NULL, NULL, fun2_names, fun2, 0, ctx)) < 0)
579 return AVERROR(EINVAL);
584 static int command(AVFilterContext *ctx, const char *cmd, const char *arg, char *res, int res_len, int flags)
586 DrawTextContext *dtext = ctx->priv;
588 if (!strcmp(cmd, "reinit")) {
592 if ((ret = init(ctx, arg, NULL)) < 0)
594 return config_input(ctx->inputs[0]);
597 return AVERROR(ENOSYS);
600 static int draw_glyphs(DrawTextContext *dtext, AVFilterBufferRef *picref,
601 int width, int height, const uint8_t rgbcolor[4], FFDrawColor *color, int x, int y)
603 char *text = dtext->expanded_text;
609 for (i = 0, p = text; *p; i++) {
611 GET_UTF8(code, *p++, continue;);
613 /* skip new line chars, just go to new line */
614 if (code == '\n' || code == '\r' || code == '\t')
618 glyph = av_tree_find(dtext->glyphs, &dummy, (void *)glyph_cmp, NULL);
620 if (glyph->bitmap.pixel_mode != FT_PIXEL_MODE_MONO &&
621 glyph->bitmap.pixel_mode != FT_PIXEL_MODE_GRAY)
622 return AVERROR(EINVAL);
624 x1 = dtext->positions[i].x+dtext->x+x;
625 y1 = dtext->positions[i].y+dtext->y+y;
627 ff_blend_mask(&dtext->dc, color,
628 picref->data, picref->linesize, width, height,
629 glyph->bitmap.buffer, glyph->bitmap.pitch,
630 glyph->bitmap.width, glyph->bitmap.rows,
631 glyph->bitmap.pixel_mode == FT_PIXEL_MODE_MONO ? 0 : 3,
638 static int draw_text(AVFilterContext *ctx, AVFilterBufferRef *picref,
639 int width, int height)
641 DrawTextContext *dtext = ctx->priv;
642 uint32_t code = 0, prev_code = 0;
643 int x = 0, y = 0, i = 0, ret;
644 int max_text_line_w = 0, len;
646 char *text = dtext->text;
648 int y_min = 32000, y_max = -32000;
649 int x_min = 32000, x_max = -32000;
651 Glyph *glyph = NULL, *prev_glyph = NULL;
654 time_t now = time(0);
656 uint8_t *buf = dtext->expanded_text;
657 int buf_size = dtext->expanded_text_size;
659 if(dtext->basetime != AV_NOPTS_VALUE)
660 now= picref->pts*av_q2d(ctx->inputs[0]->time_base) + dtext->basetime/1000000;
663 buf_size = 2*strlen(dtext->text)+1;
664 buf = av_malloc(buf_size);
668 localtime_r(&now, <ime);
670 if(strchr(dtext->text, '%'))
671 ltime= *localtime(&now);
676 if (strftime(buf, buf_size, dtext->text, <ime) != 0 || *buf == 0)
679 } while ((buf = av_realloc(buf, buf_size)));
681 if (dtext->tc_opt_string) {
682 char tcbuf[AV_TIMECODE_STR_SIZE];
683 av_timecode_make_string(&dtext->tc, tcbuf, dtext->frame_id++);
684 buf = av_asprintf("%s%s", dtext->text, tcbuf);
688 return AVERROR(ENOMEM);
689 text = dtext->expanded_text = buf;
690 dtext->expanded_text_size = buf_size;
691 if ((len = strlen(text)) > dtext->nb_positions) {
692 if (!(dtext->positions =
693 av_realloc(dtext->positions, len*sizeof(*dtext->positions))))
694 return AVERROR(ENOMEM);
695 dtext->nb_positions = len;
701 /* load and cache glyphs */
702 for (i = 0, p = text; *p; i++) {
703 GET_UTF8(code, *p++, continue;);
707 glyph = av_tree_find(dtext->glyphs, &dummy, glyph_cmp, NULL);
709 load_glyph(ctx, &glyph, code);
712 y_min = FFMIN(glyph->bbox.yMin, y_min);
713 y_max = FFMAX(glyph->bbox.yMax, y_max);
714 x_min = FFMIN(glyph->bbox.xMin, x_min);
715 x_max = FFMAX(glyph->bbox.xMax, x_max);
717 dtext->max_glyph_h = y_max - y_min;
718 dtext->max_glyph_w = x_max - x_min;
720 /* compute and save position for each glyph */
722 for (i = 0, p = text; *p; i++) {
723 GET_UTF8(code, *p++, continue;);
725 /* skip the \n in the sequence \r\n */
726 if (prev_code == '\r' && code == '\n')
730 if (is_newline(code)) {
731 max_text_line_w = FFMAX(max_text_line_w, x);
732 y += dtext->max_glyph_h;
740 glyph = av_tree_find(dtext->glyphs, &dummy, glyph_cmp, NULL);
743 if (dtext->use_kerning && prev_glyph && glyph->code) {
744 FT_Get_Kerning(dtext->face, prev_glyph->code, glyph->code,
745 ft_kerning_default, &delta);
750 dtext->positions[i].x = x + glyph->bitmap_left;
751 dtext->positions[i].y = y - glyph->bitmap_top + y_max;
752 if (code == '\t') x = (x / dtext->tabsize + 1)*dtext->tabsize;
753 else x += glyph->advance;
756 max_text_line_w = FFMAX(x, max_text_line_w);
758 dtext->var_values[VAR_TW] = dtext->var_values[VAR_TEXT_W] = max_text_line_w;
759 dtext->var_values[VAR_TH] = dtext->var_values[VAR_TEXT_H] = y + dtext->max_glyph_h;
761 dtext->var_values[VAR_MAX_GLYPH_W] = dtext->max_glyph_w;
762 dtext->var_values[VAR_MAX_GLYPH_H] = dtext->max_glyph_h;
763 dtext->var_values[VAR_MAX_GLYPH_A] = dtext->var_values[VAR_ASCENT ] = y_max;
764 dtext->var_values[VAR_MAX_GLYPH_D] = dtext->var_values[VAR_DESCENT] = y_min;
766 dtext->var_values[VAR_LINE_H] = dtext->var_values[VAR_LH] = dtext->max_glyph_h;
768 dtext->x = dtext->var_values[VAR_X] = av_expr_eval(dtext->x_pexpr, dtext->var_values, &dtext->prng);
769 dtext->y = dtext->var_values[VAR_Y] = av_expr_eval(dtext->y_pexpr, dtext->var_values, &dtext->prng);
770 dtext->x = dtext->var_values[VAR_X] = av_expr_eval(dtext->x_pexpr, dtext->var_values, &dtext->prng);
771 dtext->draw = av_expr_eval(dtext->draw_pexpr, dtext->var_values, &dtext->prng);
776 box_w = FFMIN(width - 1 , max_text_line_w);
777 box_h = FFMIN(height - 1, y + dtext->max_glyph_h);
781 ff_blend_rectangle(&dtext->dc, &dtext->boxcolor,
782 picref->data, picref->linesize, width, height,
783 dtext->x, dtext->y, box_w, box_h);
785 if (dtext->shadowx || dtext->shadowy) {
786 if ((ret = draw_glyphs(dtext, picref, width, height, dtext->shadowcolor.rgba,
787 &dtext->shadowcolor, dtext->shadowx, dtext->shadowy)) < 0)
791 if ((ret = draw_glyphs(dtext, picref, width, height, dtext->fontcolor.rgba,
792 &dtext->fontcolor, 0, 0)) < 0)
798 static void null_draw_slice(AVFilterLink *link, int y, int h, int slice_dir) { }
800 static void end_frame(AVFilterLink *inlink)
802 AVFilterContext *ctx = inlink->dst;
803 AVFilterLink *outlink = ctx->outputs[0];
804 DrawTextContext *dtext = ctx->priv;
805 AVFilterBufferRef *picref = inlink->cur_buf;
807 dtext->var_values[VAR_T] = picref->pts == AV_NOPTS_VALUE ?
808 NAN : picref->pts * av_q2d(inlink->time_base);
810 draw_text(ctx, picref, picref->video->w, picref->video->h);
812 av_log(ctx, AV_LOG_DEBUG, "n:%d t:%f text_w:%d text_h:%d x:%d y:%d\n",
813 (int)dtext->var_values[VAR_N], dtext->var_values[VAR_T],
814 (int)dtext->var_values[VAR_TEXT_W], (int)dtext->var_values[VAR_TEXT_H],
817 dtext->var_values[VAR_N] += 1.0;
819 ff_draw_slice(outlink, 0, picref->video->h, 1);
820 ff_end_frame(outlink);
823 AVFilter avfilter_vf_drawtext = {
825 .description = NULL_IF_CONFIG_SMALL("Draw text on top of video frames using libfreetype library."),
826 .priv_size = sizeof(DrawTextContext),
829 .query_formats = query_formats,
831 .inputs = (const AVFilterPad[]) {{ .name = "default",
832 .type = AVMEDIA_TYPE_VIDEO,
833 .get_video_buffer = ff_null_get_video_buffer,
834 .start_frame = ff_null_start_frame,
835 .draw_slice = null_draw_slice,
836 .end_frame = end_frame,
837 .config_props = config_input,
838 .min_perms = AV_PERM_WRITE |
840 .rej_perms = AV_PERM_PRESERVE },
842 .outputs = (const AVFilterPad[]) {{ .name = "default",
843 .type = AVMEDIA_TYPE_VIDEO, },
845 .process_command = command,