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 FFmpeg vhook/drawtext.c
26 * filter by Gustavo Sverzut Barbieri
32 #include "libavutil/colorspace.h"
33 #include "libavutil/file.h"
34 #include "libavutil/opt.h"
35 #include "libavutil/parseutils.h"
36 #include "libavutil/pixdesc.h"
37 #include "libavutil/tree.h"
39 #include "drawutils.h"
44 #include <freetype/config/ftheader.h>
45 #include FT_FREETYPE_H
50 uint8_t *fontfile; ///< font to be used
51 uint8_t *text; ///< text to be drawn
52 uint8_t *expanded_text; ///< used to contain the strftime()-expanded text
53 size_t expanded_text_size; ///< size in bytes of the expanded_text buffer
54 int ft_load_flags; ///< flags used for loading fonts, see FT_LOAD_*
55 FT_Vector *positions; ///< positions for each element in the text
56 size_t nb_positions; ///< number of elements of positions array
57 char *textfile; ///< file with text to be drawn
58 unsigned int x; ///< x position to start drawing text
59 unsigned int y; ///< y position to start drawing text
61 unsigned int fontsize; ///< font size to use
62 char *fontcolor_string; ///< font color as string
63 char *boxcolor_string; ///< box color as string
64 char *shadowcolor_string; ///< shadow color as string
65 uint8_t fontcolor[4]; ///< foreground color
66 uint8_t boxcolor[4]; ///< background color
67 uint8_t shadowcolor[4]; ///< shadow color
68 uint8_t fontcolor_rgba[4]; ///< foreground color in RGBA
69 uint8_t boxcolor_rgba[4]; ///< background color in RGBA
70 uint8_t shadowcolor_rgba[4]; ///< shadow color in RGBA
72 short int draw_box; ///< draw box around text - true or false
73 int use_kerning; ///< font kerning is used - true/false
74 int tabsize; ///< tab size
76 FT_Library library; ///< freetype font library handle
77 FT_Face face; ///< freetype font face handle
78 struct AVTreeNode *glyphs; ///< rendered glyphs, stored using the UTF-32 char code
79 int hsub, vsub; ///< chroma subsampling values
81 int pixel_step[4]; ///< distance in bytes between the component of each pixel
82 uint8_t rgba_map[4]; ///< map RGBA offsets to the positions in the packed RGBA format
83 uint8_t *box_line[4]; ///< line used for filling the box background
86 #define OFFSET(x) offsetof(DrawTextContext, x)
88 static const AVOption drawtext_options[]= {
89 {"fontfile", "set font file", OFFSET(fontfile), FF_OPT_TYPE_STRING, {.str=NULL}, CHAR_MIN, CHAR_MAX },
90 {"text", "set text", OFFSET(text), FF_OPT_TYPE_STRING, {.str=NULL}, CHAR_MIN, CHAR_MAX },
91 {"textfile", "set text file", OFFSET(textfile), FF_OPT_TYPE_STRING, {.str=NULL}, CHAR_MIN, CHAR_MAX },
92 {"fontcolor","set foreground color", OFFSET(fontcolor_string), FF_OPT_TYPE_STRING, {.str=NULL}, CHAR_MIN, CHAR_MAX },
93 {"boxcolor", "set box color", OFFSET(boxcolor_string), FF_OPT_TYPE_STRING, {.str=NULL}, CHAR_MIN, CHAR_MAX },
94 {"shadowcolor", "set shadow color", OFFSET(shadowcolor_string), FF_OPT_TYPE_STRING, {.str=NULL}, CHAR_MIN, CHAR_MAX },
95 {"box", "set box", OFFSET(draw_box), FF_OPT_TYPE_INT, {.dbl=0}, 0, 1 },
96 {"fontsize", "set font size", OFFSET(fontsize), FF_OPT_TYPE_INT, {.dbl=16}, 1, 72 },
97 {"x", "set x", OFFSET(x), FF_OPT_TYPE_INT, {.dbl=0}, 0, INT_MAX },
98 {"y", "set y", OFFSET(y), FF_OPT_TYPE_INT, {.dbl=0}, 0, INT_MAX },
99 {"shadowx", "set x", OFFSET(shadowx), FF_OPT_TYPE_INT, {.dbl=0}, INT_MIN, INT_MAX },
100 {"shadowy", "set y", OFFSET(shadowy), FF_OPT_TYPE_INT, {.dbl=0}, INT_MIN, INT_MAX },
101 {"tabsize", "set tab size", OFFSET(tabsize), FF_OPT_TYPE_INT, {.dbl=4}, 0, INT_MAX },
103 /* FT_LOAD_* flags */
104 {"ft_load_flags", "set font loading flags for libfreetype", OFFSET(ft_load_flags), FF_OPT_TYPE_FLAGS, {.dbl=FT_LOAD_DEFAULT|FT_LOAD_RENDER}, 0, INT_MAX, 0, "ft_load_flags" },
105 {"default", "set default", 0, FF_OPT_TYPE_CONST, {.dbl=FT_LOAD_DEFAULT}, INT_MIN, INT_MAX, 0, "ft_load_flags" },
106 {"no_scale", "set no_scale", 0, FF_OPT_TYPE_CONST, {.dbl=FT_LOAD_NO_SCALE}, INT_MIN, INT_MAX, 0, "ft_load_flags" },
107 {"no_hinting", "set no_hinting", 0, FF_OPT_TYPE_CONST, {.dbl=FT_LOAD_NO_HINTING}, INT_MIN, INT_MAX, 0, "ft_load_flags" },
108 {"render", "set render", 0, FF_OPT_TYPE_CONST, {.dbl=FT_LOAD_RENDER}, INT_MIN, INT_MAX, 0, "ft_load_flags" },
109 {"no_bitmap", "set no_bitmap", 0, FF_OPT_TYPE_CONST, {.dbl=FT_LOAD_NO_BITMAP}, INT_MIN, INT_MAX, 0, "ft_load_flags" },
110 {"vertical_layout", "set vertical_layout", 0, FF_OPT_TYPE_CONST, {.dbl=FT_LOAD_VERTICAL_LAYOUT}, INT_MIN, INT_MAX, 0, "ft_load_flags" },
111 {"force_autohint", "set force_autohint", 0, FF_OPT_TYPE_CONST, {.dbl=FT_LOAD_FORCE_AUTOHINT}, INT_MIN, INT_MAX, 0, "ft_load_flags" },
112 {"crop_bitmap", "set crop_bitmap", 0, FF_OPT_TYPE_CONST, {.dbl=FT_LOAD_CROP_BITMAP}, INT_MIN, INT_MAX, 0, "ft_load_flags" },
113 {"pedantic", "set pedantic", 0, FF_OPT_TYPE_CONST, {.dbl=FT_LOAD_PEDANTIC}, INT_MIN, INT_MAX, 0, "ft_load_flags" },
114 {"ignore_global_advance_width", "set ignore_global_advance_width", 0, FF_OPT_TYPE_CONST, {.dbl=FT_LOAD_IGNORE_GLOBAL_ADVANCE_WIDTH}, INT_MIN, INT_MAX, 0, "ft_load_flags" },
115 {"no_recurse", "set no_recurse", 0, FF_OPT_TYPE_CONST, {.dbl=FT_LOAD_NO_RECURSE}, INT_MIN, INT_MAX, 0, "ft_load_flags" },
116 {"ignore_transform", "set ignore_transform", 0, FF_OPT_TYPE_CONST, {.dbl=FT_LOAD_IGNORE_TRANSFORM}, INT_MIN, INT_MAX, 0, "ft_load_flags" },
117 {"monochrome", "set monochrome", 0, FF_OPT_TYPE_CONST, {.dbl=FT_LOAD_MONOCHROME}, INT_MIN, INT_MAX, 0, "ft_load_flags" },
118 {"linear_design", "set linear_design", 0, FF_OPT_TYPE_CONST, {.dbl=FT_LOAD_LINEAR_DESIGN}, INT_MIN, INT_MAX, 0, "ft_load_flags" },
119 {"no_autohint", "set no_autohint", 0, FF_OPT_TYPE_CONST, {.dbl=FT_LOAD_NO_AUTOHINT}, INT_MIN, INT_MAX, 0, "ft_load_flags" },
123 static const char *drawtext_get_name(void *ctx)
128 static const AVClass drawtext_class = {
134 #undef __FTERRORS_H__
135 #define FT_ERROR_START_LIST {
136 #define FT_ERRORDEF(e, v, s) { (e), (s) },
137 #define FT_ERROR_END_LIST { 0, NULL } };
143 } static ft_errors[] =
146 #define FT_ERRMSG(e) ft_errors[e].err_msg
151 FT_Bitmap bitmap; ///< array holding bitmaps of font
158 static int glyph_cmp(void *key, const void *b)
160 const Glyph *a = key, *bb = b;
161 int64_t diff = (int64_t)a->code - (int64_t)bb->code;
162 return diff > 0 ? 1 : diff < 0 ? -1 : 0;
166 * Load glyphs corresponding to the UTF-32 codepoint code.
168 static int load_glyph(AVFilterContext *ctx, Glyph **glyph_ptr, uint32_t code)
170 DrawTextContext *dtext = ctx->priv;
172 struct AVTreeNode *node = NULL;
175 /* load glyph into dtext->face->glyph */
176 if (FT_Load_Char(dtext->face, code, dtext->ft_load_flags))
177 return AVERROR(EINVAL);
180 if (!(glyph = av_mallocz(sizeof(*glyph))) ||
181 !(glyph->glyph = av_mallocz(sizeof(*glyph->glyph)))) {
182 ret = AVERROR(ENOMEM);
187 if (FT_Get_Glyph(dtext->face->glyph, glyph->glyph)) {
188 ret = AVERROR(EINVAL);
192 glyph->bitmap = dtext->face->glyph->bitmap;
193 glyph->bitmap_left = dtext->face->glyph->bitmap_left;
194 glyph->bitmap_top = dtext->face->glyph->bitmap_top;
195 glyph->advance = dtext->face->glyph->advance.x >> 6;
197 /* measure text height to calculate text_height (or the maximum text height) */
198 FT_Glyph_Get_CBox(*glyph->glyph, ft_glyph_bbox_pixels, &glyph->bbox);
200 /* cache the newly created glyph */
201 if (!(node = av_mallocz(av_tree_node_size))) {
202 ret = AVERROR(ENOMEM);
205 av_tree_insert(&dtext->glyphs, glyph, glyph_cmp, &node);
213 av_freep(&glyph->glyph);
219 static av_cold int init(AVFilterContext *ctx, const char *args, void *opaque)
222 DrawTextContext *dtext = ctx->priv;
225 dtext->class = &drawtext_class;
226 av_opt_set_defaults2(dtext, 0, 0);
227 dtext->fontcolor_string = av_strdup("black");
228 dtext->boxcolor_string = av_strdup("white");
229 dtext->shadowcolor_string = av_strdup("black");
231 if ((err = (av_set_options_string(dtext, args, "=", ":"))) < 0) {
232 av_log(ctx, AV_LOG_ERROR, "Error parsing options string: '%s'\n", args);
236 if (!dtext->fontfile) {
237 av_log(ctx, AV_LOG_ERROR, "No font filename provided\n");
238 return AVERROR(EINVAL);
241 if (dtext->textfile) {
246 av_log(ctx, AV_LOG_ERROR,
247 "Both text and text file provided. Please provide only one\n");
248 return AVERROR(EINVAL);
250 if ((err = av_file_map(dtext->textfile, &textbuf, &textbuf_size, 0, ctx)) < 0) {
251 av_log(ctx, AV_LOG_ERROR,
252 "The text file '%s' could not be read or is empty\n",
257 if (!(dtext->text = av_malloc(textbuf_size+1)))
258 return AVERROR(ENOMEM);
259 memcpy(dtext->text, textbuf, textbuf_size);
260 dtext->text[textbuf_size] = 0;
261 av_file_unmap(textbuf, textbuf_size);
265 av_log(ctx, AV_LOG_ERROR,
266 "Either text or a valid file must be provided\n");
267 return AVERROR(EINVAL);
270 if ((err = av_parse_color(dtext->fontcolor_rgba, dtext->fontcolor_string, -1, ctx))) {
271 av_log(ctx, AV_LOG_ERROR,
272 "Invalid font color '%s'\n", dtext->fontcolor_string);
276 if ((err = av_parse_color(dtext->boxcolor_rgba, dtext->boxcolor_string, -1, ctx))) {
277 av_log(ctx, AV_LOG_ERROR,
278 "Invalid box color '%s'\n", dtext->boxcolor_string);
282 if ((err = av_parse_color(dtext->shadowcolor_rgba, dtext->shadowcolor_string, -1, ctx))) {
283 av_log(ctx, AV_LOG_ERROR,
284 "Invalid shadow color '%s'\n", dtext->shadowcolor_string);
288 if ((err = FT_Init_FreeType(&(dtext->library)))) {
289 av_log(ctx, AV_LOG_ERROR,
290 "Could not load FreeType: %s\n", FT_ERRMSG(err));
291 return AVERROR(EINVAL);
294 /* load the face, and set up the encoding, which is by default UTF-8 */
295 if ((err = FT_New_Face(dtext->library, dtext->fontfile, 0, &dtext->face))) {
296 av_log(ctx, AV_LOG_ERROR, "Could not load fontface from file '%s': %s\n",
297 dtext->fontfile, FT_ERRMSG(err));
298 return AVERROR(EINVAL);
300 if ((err = FT_Set_Pixel_Sizes(dtext->face, 0, dtext->fontsize))) {
301 av_log(ctx, AV_LOG_ERROR, "Could not set font size to %d pixels: %s\n",
302 dtext->fontsize, FT_ERRMSG(err));
303 return AVERROR(EINVAL);
306 dtext->use_kerning = FT_HAS_KERNING(dtext->face);
308 /* load the fallback glyph with code 0 */
309 load_glyph(ctx, NULL, 0);
311 /* set the tabsize in pixels */
312 if ((err = load_glyph(ctx, &glyph, ' ') < 0)) {
313 av_log(ctx, AV_LOG_ERROR, "Could not set tabsize.\n");
316 dtext->tabsize *= glyph->advance;
318 #if !HAVE_LOCALTIME_R
319 av_log(ctx, AV_LOG_WARNING, "strftime() expansion unavailable!\n");
325 static int query_formats(AVFilterContext *ctx)
327 static const enum PixelFormat pix_fmts[] = {
328 PIX_FMT_ARGB, PIX_FMT_RGBA,
329 PIX_FMT_ABGR, PIX_FMT_BGRA,
330 PIX_FMT_RGB24, PIX_FMT_BGR24,
331 PIX_FMT_YUV420P, PIX_FMT_YUV444P,
332 PIX_FMT_YUV422P, PIX_FMT_YUV411P,
333 PIX_FMT_YUV410P, PIX_FMT_YUV440P,
337 avfilter_set_common_pixel_formats(ctx, avfilter_make_format_list(pix_fmts));
341 static int glyph_enu_free(void *opaque, void *elem)
347 static av_cold void uninit(AVFilterContext *ctx)
349 DrawTextContext *dtext = ctx->priv;
352 av_freep(&dtext->fontfile);
353 av_freep(&dtext->text);
354 av_freep(&dtext->expanded_text);
355 av_freep(&dtext->fontcolor_string);
356 av_freep(&dtext->boxcolor_string);
357 av_freep(&dtext->positions);
358 av_freep(&dtext->shadowcolor_string);
359 av_tree_enumerate(dtext->glyphs, NULL, NULL, glyph_enu_free);
360 av_tree_destroy(dtext->glyphs);
362 FT_Done_Face(dtext->face);
363 FT_Done_FreeType(dtext->library);
365 for (i = 0; i < 4; i++) {
366 av_freep(&dtext->box_line[i]);
367 dtext->pixel_step[i] = 0;
372 static int config_input(AVFilterLink *inlink)
374 DrawTextContext *dtext = inlink->dst->priv;
375 const AVPixFmtDescriptor *pix_desc = &av_pix_fmt_descriptors[inlink->format];
378 dtext->hsub = pix_desc->log2_chroma_w;
379 dtext->vsub = pix_desc->log2_chroma_h;
382 ff_fill_line_with_color(dtext->box_line, dtext->pixel_step,
383 inlink->w, dtext->boxcolor,
384 inlink->format, dtext->boxcolor_rgba,
385 &dtext->is_packed_rgb, dtext->rgba_map)) < 0)
388 if (!dtext->is_packed_rgb) {
389 uint8_t *rgba = dtext->fontcolor_rgba;
390 dtext->fontcolor[0] = RGB_TO_Y_CCIR(rgba[0], rgba[1], rgba[2]);
391 dtext->fontcolor[1] = RGB_TO_U_CCIR(rgba[0], rgba[1], rgba[2], 0);
392 dtext->fontcolor[2] = RGB_TO_V_CCIR(rgba[0], rgba[1], rgba[2], 0);
393 dtext->fontcolor[3] = rgba[3];
394 rgba = dtext->shadowcolor_rgba;
395 dtext->shadowcolor[0] = RGB_TO_Y_CCIR(rgba[0], rgba[1], rgba[2]);
396 dtext->shadowcolor[1] = RGB_TO_U_CCIR(rgba[0], rgba[1], rgba[2], 0);
397 dtext->shadowcolor[2] = RGB_TO_V_CCIR(rgba[0], rgba[1], rgba[2], 0);
398 dtext->shadowcolor[3] = rgba[3];
404 #define GET_BITMAP_VAL(r, c) \
405 bitmap->pixel_mode == FT_PIXEL_MODE_MONO ? \
406 (bitmap->buffer[(r) * bitmap->pitch + ((c)>>3)] & (0x80 >> ((c)&7))) * 255 : \
407 bitmap->buffer[(r) * bitmap->pitch + (c)]
409 #define SET_PIXEL_YUV(picref, yuva_color, val, x, y, hsub, vsub) { \
410 luma_pos = ((x) ) + ((y) ) * picref->linesize[0]; \
411 alpha = yuva_color[3] * (val) * 129; \
412 picref->data[0][luma_pos] = (alpha * yuva_color[0] + (255*255*129 - alpha) * picref->data[0][luma_pos] ) >> 23; \
413 if (((x) & ((1<<(hsub)) - 1)) == 0 && ((y) & ((1<<(vsub)) - 1)) == 0) {\
414 chroma_pos1 = ((x) >> (hsub)) + ((y) >> (vsub)) * picref->linesize[1]; \
415 chroma_pos2 = ((x) >> (hsub)) + ((y) >> (vsub)) * picref->linesize[2]; \
416 picref->data[1][chroma_pos1] = (alpha * yuva_color[1] + (255*255*129 - alpha) * picref->data[1][chroma_pos1]) >> 23; \
417 picref->data[2][chroma_pos2] = (alpha * yuva_color[2] + (255*255*129 - alpha) * picref->data[2][chroma_pos2]) >> 23; \
421 static inline int draw_glyph_yuv(AVFilterBufferRef *picref, FT_Bitmap *bitmap, unsigned int x,
422 unsigned int y, unsigned int width, unsigned int height,
423 const uint8_t yuva_color[4], int hsub, int vsub)
426 unsigned int luma_pos, chroma_pos1, chroma_pos2;
429 for (r = 0; r < bitmap->rows && r+y < height; r++) {
430 for (c = 0; c < bitmap->width && c+x < width; c++) {
431 /* get intensity value in the glyph bitmap (source) */
432 src_val = GET_BITMAP_VAL(r, c);
436 SET_PIXEL_YUV(picref, yuva_color, src_val, c+x, y+r, hsub, vsub);
443 #define SET_PIXEL_RGB(picref, rgba_color, val, x, y, pixel_step, r_off, g_off, b_off, a_off) { \
444 p = picref->data[0] + (x) * pixel_step + ((y) * picref->linesize[0]); \
445 alpha = rgba_color[3] * (val) * 129; \
446 *(p+r_off) = (alpha * rgba_color[0] + (255*255*129 - alpha) * *(p+r_off)) >> 23; \
447 *(p+g_off) = (alpha * rgba_color[1] + (255*255*129 - alpha) * *(p+g_off)) >> 23; \
448 *(p+b_off) = (alpha * rgba_color[2] + (255*255*129 - alpha) * *(p+b_off)) >> 23; \
451 static inline int draw_glyph_rgb(AVFilterBufferRef *picref, FT_Bitmap *bitmap,
452 unsigned int x, unsigned int y,
453 unsigned int width, unsigned int height, int pixel_step,
454 const uint8_t rgba_color[4], const uint8_t rgba_map[4])
460 for (r = 0; r < bitmap->rows && r+y < height; r++) {
461 for (c = 0; c < bitmap->width && c+x < width; c++) {
462 /* get intensity value in the glyph bitmap (source) */
463 src_val = GET_BITMAP_VAL(r, c);
467 SET_PIXEL_RGB(picref, rgba_color, src_val, c+x, y+r, pixel_step,
468 rgba_map[0], rgba_map[1], rgba_map[2], rgba_map[3]);
475 static inline void drawbox(AVFilterBufferRef *picref, unsigned int x, unsigned int y,
476 unsigned int width, unsigned int height,
477 uint8_t *line[4], int pixel_step[4], uint8_t color[4],
478 int hsub, int vsub, int is_rgba_packed, uint8_t rgba_map[4])
482 if (color[3] != 0xFF) {
483 if (is_rgba_packed) {
485 for (j = 0; j < height; j++)
486 for (i = 0; i < width; i++)
487 SET_PIXEL_RGB(picref, color, 255, i+x, y+j, pixel_step[0],
488 rgba_map[0], rgba_map[1], rgba_map[2], rgba_map[3]);
490 unsigned int luma_pos, chroma_pos1, chroma_pos2;
491 for (j = 0; j < height; j++)
492 for (i = 0; i < width; i++)
493 SET_PIXEL_YUV(picref, color, 255, i+x, y+j, hsub, vsub);
496 ff_draw_rectangle(picref->data, picref->linesize,
497 line, pixel_step, hsub, vsub,
498 x, y, width, height);
502 static inline int is_newline(uint32_t c)
504 return (c == '\n' || c == '\r' || c == '\f' || c == '\v');
507 static int draw_glyphs(DrawTextContext *dtext, AVFilterBufferRef *picref,
508 int width, int height, const uint8_t rgbcolor[4], const uint8_t yuvcolor[4], int x, int y)
510 char *text = HAVE_LOCALTIME_R ? dtext->expanded_text : dtext->text;
516 for (i = 0, p = text; *p; i++) {
518 GET_UTF8(code, *p++, continue;);
520 /* skip new line chars, just go to new line */
521 if (code == '\n' || code == '\r' || code == '\t')
525 glyph = av_tree_find(dtext->glyphs, &dummy, (void *)glyph_cmp, NULL);
527 if (glyph->bitmap.pixel_mode != FT_PIXEL_MODE_MONO &&
528 glyph->bitmap.pixel_mode != FT_PIXEL_MODE_GRAY)
529 return AVERROR(EINVAL);
531 if (dtext->is_packed_rgb) {
532 draw_glyph_rgb(picref, &glyph->bitmap,
533 dtext->positions[i].x+x, dtext->positions[i].y+y, width, height,
534 dtext->pixel_step[0], rgbcolor, dtext->rgba_map);
536 draw_glyph_yuv(picref, &glyph->bitmap,
537 dtext->positions[i].x+x, dtext->positions[i].y+y, width, height,
538 yuvcolor, dtext->hsub, dtext->vsub);
545 static int draw_text(AVFilterContext *ctx, AVFilterBufferRef *picref,
546 int width, int height)
548 DrawTextContext *dtext = ctx->priv;
549 uint32_t code = 0, prev_code = 0;
550 int x = 0, y = 0, i = 0, ret;
551 int text_height, baseline;
552 char *text = dtext->text;
555 int y_min = 32000, y_max = -32000;
557 Glyph *glyph = NULL, *prev_glyph = NULL;
561 time_t now = time(0);
563 uint8_t *buf = dtext->expanded_text;
564 int buf_size = dtext->expanded_text_size;
567 buf_size = 2*strlen(dtext->text)+1;
568 buf = av_malloc(buf_size);
571 localtime_r(&now, <ime);
575 if (strftime(buf, buf_size, dtext->text, <ime) != 0 || *buf == 0)
578 } while ((buf = av_realloc(buf, buf_size)));
581 return AVERROR(ENOMEM);
582 text = dtext->expanded_text = buf;
583 dtext->expanded_text_size = buf_size;
585 if ((len = strlen(text)) > dtext->nb_positions) {
586 if (!(dtext->positions =
587 av_realloc(dtext->positions, len*sizeof(*dtext->positions))))
588 return AVERROR(ENOMEM);
589 dtext->nb_positions = len;
595 /* load and cache glyphs */
596 for (i = 0, p = text; *p; i++) {
597 GET_UTF8(code, *p++, continue;);
601 glyph = av_tree_find(dtext->glyphs, &dummy, glyph_cmp, NULL);
603 load_glyph(ctx, &glyph, code);
605 y_min = FFMIN(glyph->bbox.yMin, y_min);
606 y_max = FFMAX(glyph->bbox.yMax, y_max);
608 text_height = y_max - y_min;
611 /* compute and save position for each glyph */
613 for (i = 0, p = text; *p; i++) {
614 GET_UTF8(code, *p++, continue;);
616 /* skip the \n in the sequence \r\n */
617 if (prev_code == '\r' && code == '\n')
621 if (is_newline(code)) {
622 str_w = FFMAX(str_w, x - dtext->x);
631 glyph = av_tree_find(dtext->glyphs, &dummy, glyph_cmp, NULL);
634 if (dtext->use_kerning && prev_glyph && glyph->code) {
635 FT_Get_Kerning(dtext->face, prev_glyph->code, glyph->code,
636 ft_kerning_default, &delta);
640 if (x + glyph->bbox.xMax >= width) {
641 str_w = FFMAX(str_w, x - dtext->x);
647 dtext->positions[i].x = x + glyph->bitmap_left;
648 dtext->positions[i].y = y - glyph->bitmap_top + baseline;
649 if (code == '\t') x = (x / dtext->tabsize + 1)*dtext->tabsize;
650 else x += glyph->advance;
653 str_w = FFMIN(width - dtext->x - 1, FFMAX(str_w, x - dtext->x));
654 y = FFMIN(y + text_height, height - 1);
658 drawbox(picref, dtext->x, dtext->y, str_w, y-dtext->y,
659 dtext->box_line, dtext->pixel_step, dtext->boxcolor,
660 dtext->hsub, dtext->vsub, dtext->is_packed_rgb, dtext->rgba_map);
662 if (dtext->shadowx || dtext->shadowy) {
663 if ((ret = draw_glyphs(dtext, picref, width, height, dtext->shadowcolor_rgba,
664 dtext->shadowcolor, dtext->shadowx, dtext->shadowy)) < 0)
668 if ((ret = draw_glyphs(dtext, picref, width, height, dtext->fontcolor_rgba,
669 dtext->fontcolor, 0, 0)) < 0)
675 static void null_draw_slice(AVFilterLink *link, int y, int h, int slice_dir) { }
677 static void end_frame(AVFilterLink *inlink)
679 AVFilterLink *outlink = inlink->dst->outputs[0];
680 AVFilterBufferRef *picref = inlink->cur_buf;
682 draw_text(inlink->dst, picref, picref->video->w, picref->video->h);
684 avfilter_draw_slice(outlink, 0, picref->video->h, 1);
685 avfilter_end_frame(outlink);
688 AVFilter avfilter_vf_drawtext = {
690 .description = NULL_IF_CONFIG_SMALL("Draw text on top of video frames using libfreetype library."),
691 .priv_size = sizeof(DrawTextContext),
694 .query_formats = query_formats,
696 .inputs = (AVFilterPad[]) {{ .name = "default",
697 .type = AVMEDIA_TYPE_VIDEO,
698 .get_video_buffer = avfilter_null_get_video_buffer,
699 .start_frame = avfilter_null_start_frame,
700 .draw_slice = null_draw_slice,
701 .end_frame = end_frame,
702 .config_props = config_input,
703 .min_perms = AV_PERM_WRITE |
705 .rej_perms = AV_PERM_PRESERVE },
707 .outputs = (AVFilterPad[]) {{ .name = "default",
708 .type = AVMEDIA_TYPE_VIDEO, },