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 *text_priv; ///< used to detect whether text changed
53 int ft_load_flags; ///< flags used for loading fonts, see FT_LOAD_*
54 FT_Vector *positions; ///< positions for each element in the text
55 char *textfile; ///< file with text to be drawn
56 unsigned int x; ///< x position to start drawing text
57 unsigned int y; ///< y position to start drawing text
59 unsigned int fontsize; ///< font size to use
60 char *fontcolor_string; ///< font color as string
61 char *boxcolor_string; ///< box color as string
62 char *shadowcolor_string; ///< shadow color as string
63 uint8_t fontcolor[4]; ///< foreground color
64 uint8_t boxcolor[4]; ///< background color
65 uint8_t shadowcolor[4]; ///< shadow color
66 uint8_t fontcolor_rgba[4]; ///< foreground color in RGBA
67 uint8_t boxcolor_rgba[4]; ///< background color in RGBA
68 uint8_t shadowcolor_rgba[4]; ///< shadow color in RGBA
70 short int draw_box; ///< draw box around text - true or false
71 int use_kerning; ///< font kerning is used - true/false
72 int tabsize; ///< tab size
74 FT_Library library; ///< freetype font library handle
75 FT_Face face; ///< freetype font face handle
76 struct AVTreeNode *glyphs; ///< rendered glyphs, stored using the UTF-32 char code
77 int hsub, vsub; ///< chroma subsampling values
79 int pixel_step[4]; ///< distance in bytes between the component of each pixel
80 uint8_t rgba_map[4]; ///< map RGBA offsets to the positions in the packed RGBA format
81 uint8_t *box_line[4]; ///< line used for filling the box background
84 #define OFFSET(x) offsetof(DrawTextContext, x)
86 static const AVOption drawtext_options[]= {
87 {"fontfile", "set font file", OFFSET(fontfile), FF_OPT_TYPE_STRING, 0, CHAR_MIN, CHAR_MAX },
88 {"text", "set text", OFFSET(text), FF_OPT_TYPE_STRING, 0, CHAR_MIN, CHAR_MAX },
89 {"textfile", "set text file", OFFSET(textfile), FF_OPT_TYPE_STRING, 0, CHAR_MIN, CHAR_MAX },
90 {"fontcolor","set foreground color", OFFSET(fontcolor_string), FF_OPT_TYPE_STRING, 0, CHAR_MIN, CHAR_MAX },
91 {"boxcolor", "set box color", OFFSET(boxcolor_string), FF_OPT_TYPE_STRING, 0, CHAR_MIN, CHAR_MAX },
92 {"shadowcolor", "set shadow color", OFFSET(shadowcolor_string), FF_OPT_TYPE_STRING, 0, CHAR_MIN, CHAR_MAX },
93 {"box", "set box", OFFSET(draw_box), FF_OPT_TYPE_INT, 0, 0, 1 },
94 {"fontsize", "set font size", OFFSET(fontsize), FF_OPT_TYPE_INT, 16, 1, 72 },
95 {"x", "set x", OFFSET(x), FF_OPT_TYPE_INT, 0, 0, INT_MAX },
96 {"y", "set y", OFFSET(y), FF_OPT_TYPE_INT, 0, 0, INT_MAX },
97 {"shadowx", "set x", OFFSET(shadowx), FF_OPT_TYPE_INT, 0, INT_MIN, INT_MAX },
98 {"shadowy", "set y", OFFSET(shadowy), FF_OPT_TYPE_INT, 0, INT_MIN, INT_MAX },
99 {"tabsize", "set tab size", OFFSET(tabsize), FF_OPT_TYPE_INT, 4, 0, INT_MAX },
101 /* FT_LOAD_* flags */
102 {"ft_load_flags", "set font loading flags for libfreetype", OFFSET(ft_load_flags), FF_OPT_TYPE_FLAGS, FT_LOAD_DEFAULT|FT_LOAD_RENDER, 0, INT_MAX, 0, "ft_load_flags" },
103 {"default", "set default", 0, FF_OPT_TYPE_CONST, FT_LOAD_DEFAULT, INT_MIN, INT_MAX, 0, "ft_load_flags" },
104 {"no_scale", "set no_scale", 0, FF_OPT_TYPE_CONST, FT_LOAD_NO_SCALE, INT_MIN, INT_MAX, 0, "ft_load_flags" },
105 {"no_hinting", "set no_hinting", 0, FF_OPT_TYPE_CONST, FT_LOAD_NO_HINTING, INT_MIN, INT_MAX, 0, "ft_load_flags" },
106 {"render", "set render", 0, FF_OPT_TYPE_CONST, FT_LOAD_RENDER, INT_MIN, INT_MAX, 0, "ft_load_flags" },
107 {"no_bitmap", "set no_bitmap", 0, FF_OPT_TYPE_CONST, FT_LOAD_NO_BITMAP, INT_MIN, INT_MAX, 0, "ft_load_flags" },
108 {"vertical_layout", "set vertical_layout", 0, FF_OPT_TYPE_CONST, FT_LOAD_VERTICAL_LAYOUT, INT_MIN, INT_MAX, 0, "ft_load_flags" },
109 {"force_autohint", "set force_autohint", 0, FF_OPT_TYPE_CONST, FT_LOAD_FORCE_AUTOHINT, INT_MIN, INT_MAX, 0, "ft_load_flags" },
110 {"crop_bitmap", "set crop_bitmap", 0, FF_OPT_TYPE_CONST, FT_LOAD_CROP_BITMAP, INT_MIN, INT_MAX, 0, "ft_load_flags" },
111 {"pedantic", "set pedantic", 0, FF_OPT_TYPE_CONST, FT_LOAD_PEDANTIC, INT_MIN, INT_MAX, 0, "ft_load_flags" },
112 {"ignore_global_advance_width", "set ignore_global_advance_width", 0, FF_OPT_TYPE_CONST, FT_LOAD_IGNORE_GLOBAL_ADVANCE_WIDTH, INT_MIN, INT_MAX, 0, "ft_load_flags" },
113 {"no_recurse", "set no_recurse", 0, FF_OPT_TYPE_CONST, FT_LOAD_NO_RECURSE, INT_MIN, INT_MAX, 0, "ft_load_flags" },
114 {"ignore_transform", "set ignore_transform", 0, FF_OPT_TYPE_CONST, FT_LOAD_IGNORE_TRANSFORM, INT_MIN, INT_MAX, 0, "ft_load_flags" },
115 {"monochrome", "set monochrome", 0, FF_OPT_TYPE_CONST, FT_LOAD_MONOCHROME, INT_MIN, INT_MAX, 0, "ft_load_flags" },
116 {"linear_design", "set linear_design", 0, FF_OPT_TYPE_CONST, FT_LOAD_LINEAR_DESIGN, INT_MIN, INT_MAX, 0, "ft_load_flags" },
117 {"no_autohint", "set no_autohint", 0, FF_OPT_TYPE_CONST, FT_LOAD_NO_AUTOHINT, INT_MIN, INT_MAX, 0, "ft_load_flags" },
121 static const char *drawtext_get_name(void *ctx)
126 static const AVClass drawtext_class = {
132 #undef __FTERRORS_H__
133 #define FT_ERROR_START_LIST {
134 #define FT_ERRORDEF(e, v, s) { (e), (s) },
135 #define FT_ERROR_END_LIST { 0, NULL } };
141 } static ft_errors[] =
144 #define FT_ERRMSG(e) ft_errors[e].err_msg
149 FT_Bitmap bitmap; ///< array holding bitmaps of font
156 static int glyph_cmp(void *key, const void *b)
158 const Glyph *a = key, *bb = b;
159 int64_t diff = (int64_t)a->code - (int64_t)bb->code;
160 return diff > 0 ? 1 : diff < 0 ? -1 : 0;
164 * Load glyphs corresponding to the UTF-32 codepoint code.
166 static int load_glyph(AVFilterContext *ctx, Glyph **glyph_ptr, uint32_t code)
168 DrawTextContext *dtext = ctx->priv;
170 struct AVTreeNode *node = NULL;
173 /* load glyph into dtext->face->glyph */
174 if (FT_Load_Char(dtext->face, code, dtext->ft_load_flags))
175 return AVERROR(EINVAL);
178 if (!(glyph = av_mallocz(sizeof(*glyph))) ||
179 !(glyph->glyph = av_mallocz(sizeof(*glyph->glyph)))) {
180 ret = AVERROR(ENOMEM);
185 if (FT_Get_Glyph(dtext->face->glyph, glyph->glyph)) {
186 ret = AVERROR(EINVAL);
190 glyph->bitmap = dtext->face->glyph->bitmap;
191 glyph->bitmap_left = dtext->face->glyph->bitmap_left;
192 glyph->bitmap_top = dtext->face->glyph->bitmap_top;
193 glyph->advance = dtext->face->glyph->advance.x >> 6;
195 /* measure text height to calculate text_height (or the maximum text height) */
196 FT_Glyph_Get_CBox(*glyph->glyph, ft_glyph_bbox_pixels, &glyph->bbox);
198 /* cache the newly created glyph */
199 if (!(node = av_mallocz(av_tree_node_size))) {
200 ret = AVERROR(ENOMEM);
203 av_tree_insert(&dtext->glyphs, glyph, glyph_cmp, &node);
211 av_freep(&glyph->glyph);
217 static av_cold int init(AVFilterContext *ctx, const char *args, void *opaque)
220 DrawTextContext *dtext = ctx->priv;
223 dtext->class = &drawtext_class;
224 av_opt_set_defaults2(dtext, 0, 0);
225 dtext->fontcolor_string = av_strdup("black");
226 dtext->boxcolor_string = av_strdup("white");
227 dtext->shadowcolor_string = av_strdup("black");
229 if ((err = (av_set_options_string(dtext, args, "=", ":"))) < 0) {
230 av_log(ctx, AV_LOG_ERROR, "Error parsing options string: '%s'\n", args);
234 if (!dtext->fontfile) {
235 av_log(ctx, AV_LOG_ERROR, "No font filename provided\n");
236 return AVERROR(EINVAL);
239 if (dtext->textfile) {
244 av_log(ctx, AV_LOG_ERROR,
245 "Both text and text file provided. Please provide only one\n");
246 return AVERROR(EINVAL);
248 if ((err = av_file_map(dtext->textfile, &textbuf, &textbuf_size, 0, ctx)) < 0) {
249 av_log(ctx, AV_LOG_ERROR,
250 "The text file '%s' could not be read or is empty\n",
255 if (!(dtext->text = av_malloc(textbuf_size+1)))
256 return AVERROR(ENOMEM);
257 memcpy(dtext->text, textbuf, textbuf_size);
258 dtext->text[textbuf_size] = 0;
259 av_file_unmap(textbuf, textbuf_size);
263 av_log(ctx, AV_LOG_ERROR,
264 "Either text or a valid file must be provided\n");
265 return AVERROR(EINVAL);
268 if ((err = av_parse_color(dtext->fontcolor_rgba, dtext->fontcolor_string, -1, ctx))) {
269 av_log(ctx, AV_LOG_ERROR,
270 "Invalid font color '%s'\n", dtext->fontcolor_string);
274 if ((err = av_parse_color(dtext->boxcolor_rgba, dtext->boxcolor_string, -1, ctx))) {
275 av_log(ctx, AV_LOG_ERROR,
276 "Invalid box color '%s'\n", dtext->boxcolor_string);
280 if ((err = av_parse_color(dtext->shadowcolor_rgba, dtext->shadowcolor_string, -1, ctx))) {
281 av_log(ctx, AV_LOG_ERROR,
282 "Invalid shadow color '%s'\n", dtext->shadowcolor_string);
286 if ((err = FT_Init_FreeType(&(dtext->library)))) {
287 av_log(ctx, AV_LOG_ERROR,
288 "Could not load FreeType: %s\n", FT_ERRMSG(err));
289 return AVERROR(EINVAL);
292 /* load the face, and set up the encoding, which is by default UTF-8 */
293 if ((err = FT_New_Face(dtext->library, dtext->fontfile, 0, &dtext->face))) {
294 av_log(ctx, AV_LOG_ERROR, "Could not load fontface from file '%s': %s\n",
295 dtext->fontfile, FT_ERRMSG(err));
296 return AVERROR(EINVAL);
298 if ((err = FT_Set_Pixel_Sizes(dtext->face, 0, dtext->fontsize))) {
299 av_log(ctx, AV_LOG_ERROR, "Could not set font size to %d pixels: %s\n",
300 dtext->fontsize, FT_ERRMSG(err));
301 return AVERROR(EINVAL);
304 dtext->use_kerning = FT_HAS_KERNING(dtext->face);
306 /* load the fallback glyph with code 0 */
307 load_glyph(ctx, NULL, 0);
309 /* set the tabsize in pixels */
310 if ((err = load_glyph(ctx, &glyph, ' ') < 0)) {
311 av_log(ctx, AV_LOG_ERROR, "Could not set tabsize.\n");
314 dtext->tabsize *= glyph->advance;
316 #if !HAVE_LOCALTIME_R
317 av_log(ctx, AV_LOG_WARNING, "strftime() expansion unavailable!\n");
323 static int query_formats(AVFilterContext *ctx)
325 static const enum PixelFormat pix_fmts[] = {
326 PIX_FMT_ARGB, PIX_FMT_RGBA,
327 PIX_FMT_ABGR, PIX_FMT_BGRA,
328 PIX_FMT_RGB24, PIX_FMT_BGR24,
329 PIX_FMT_YUV420P, PIX_FMT_YUV444P,
330 PIX_FMT_YUV422P, PIX_FMT_YUV411P,
331 PIX_FMT_YUV410P, PIX_FMT_YUV440P,
335 avfilter_set_common_formats(ctx, avfilter_make_format_list(pix_fmts));
339 static int glyph_enu_free(void *opaque, void *elem)
345 static av_cold void uninit(AVFilterContext *ctx)
347 DrawTextContext *dtext = ctx->priv;
350 av_freep(&dtext->fontfile);
351 av_freep(&dtext->text);
352 av_freep(&dtext->fontcolor_string);
353 av_freep(&dtext->boxcolor_string);
354 av_freep(&dtext->positions);
355 av_freep(&dtext->shadowcolor_string);
356 av_tree_enumerate(dtext->glyphs, NULL, NULL, glyph_enu_free);
357 av_tree_destroy(dtext->glyphs);
359 FT_Done_Face(dtext->face);
360 FT_Done_FreeType(dtext->library);
362 for (i = 0; i < 4; i++) {
363 av_freep(&dtext->box_line[i]);
364 dtext->pixel_step[i] = 0;
369 static int config_input(AVFilterLink *inlink)
371 DrawTextContext *dtext = inlink->dst->priv;
372 const AVPixFmtDescriptor *pix_desc = &av_pix_fmt_descriptors[inlink->format];
375 dtext->hsub = pix_desc->log2_chroma_w;
376 dtext->vsub = pix_desc->log2_chroma_h;
379 ff_fill_line_with_color(dtext->box_line, dtext->pixel_step,
380 inlink->w, dtext->boxcolor,
381 inlink->format, dtext->boxcolor_rgba,
382 &dtext->is_packed_rgb, dtext->rgba_map)) < 0)
385 if (!dtext->is_packed_rgb) {
386 uint8_t *rgba = dtext->fontcolor_rgba;
387 dtext->fontcolor[0] = RGB_TO_Y_CCIR(rgba[0], rgba[1], rgba[2]);
388 dtext->fontcolor[1] = RGB_TO_U_CCIR(rgba[0], rgba[1], rgba[2], 0);
389 dtext->fontcolor[2] = RGB_TO_V_CCIR(rgba[0], rgba[1], rgba[2], 0);
390 dtext->fontcolor[3] = rgba[3];
391 rgba = dtext->shadowcolor_rgba;
392 dtext->shadowcolor[0] = RGB_TO_Y_CCIR(rgba[0], rgba[1], rgba[2]);
393 dtext->shadowcolor[1] = RGB_TO_U_CCIR(rgba[0], rgba[1], rgba[2], 0);
394 dtext->shadowcolor[2] = RGB_TO_V_CCIR(rgba[0], rgba[1], rgba[2], 0);
395 dtext->shadowcolor[3] = rgba[3];
401 #define GET_BITMAP_VAL(r, c) \
402 bitmap->pixel_mode == FT_PIXEL_MODE_MONO ? \
403 (bitmap->buffer[(r) * bitmap->pitch + ((c)>>3)] & (0x80 >> ((c)&7))) * 255 : \
404 bitmap->buffer[(r) * bitmap->pitch + (c)]
406 #define SET_PIXEL_YUV(picref, yuva_color, val, x, y, hsub, vsub) { \
407 luma_pos = ((x) ) + ((y) ) * picref->linesize[0]; \
408 alpha = yuva_color[3] * (val) * 129; \
409 picref->data[0][luma_pos] = (alpha * yuva_color[0] + (255*255*129 - alpha) * picref->data[0][luma_pos] ) >> 23; \
410 if (((x) & ((1<<(hsub)) - 1)) == 0 && ((y) & ((1<<(vsub)) - 1)) == 0) {\
411 chroma_pos1 = ((x) >> (hsub)) + ((y) >> (vsub)) * picref->linesize[1]; \
412 chroma_pos2 = ((x) >> (hsub)) + ((y) >> (vsub)) * picref->linesize[2]; \
413 picref->data[1][chroma_pos1] = (alpha * yuva_color[1] + (255*255*129 - alpha) * picref->data[1][chroma_pos1]) >> 23; \
414 picref->data[2][chroma_pos2] = (alpha * yuva_color[2] + (255*255*129 - alpha) * picref->data[2][chroma_pos2]) >> 23; \
418 static inline int draw_glyph_yuv(AVFilterBufferRef *picref, FT_Bitmap *bitmap, unsigned int x,
419 unsigned int y, unsigned int width, unsigned int height,
420 const uint8_t yuva_color[4], int hsub, int vsub)
423 unsigned int luma_pos, chroma_pos1, chroma_pos2;
424 uint8_t src_val, dst_pixel[4];
426 for (r = 0; r < bitmap->rows && r+y < height; r++) {
427 for (c = 0; c < bitmap->width && c+x < width; c++) {
428 /* get pixel in the picref (destination) */
429 dst_pixel[0] = picref->data[0][ c+x + (y+r) * picref->linesize[0]];
430 dst_pixel[1] = picref->data[1][((c+x) >> hsub) + ((y+r) >> vsub) * picref->linesize[1]];
431 dst_pixel[2] = picref->data[2][((c+x) >> hsub) + ((y+r) >> vsub) * picref->linesize[2]];
433 /* get intensity value in the glyph bitmap (source) */
434 src_val = GET_BITMAP_VAL(r, c);
438 SET_PIXEL_YUV(picref, yuva_color, src_val, c+x, y+r, hsub, vsub);
445 #define SET_PIXEL_RGB(picref, rgba_color, val, x, y, pixel_step, r_off, g_off, b_off, a_off) { \
446 p = picref->data[0] + (x) * pixel_step + ((y) * picref->linesize[0]); \
447 alpha = rgba_color[3] * (val) * 129; \
448 *(p+r_off) = (alpha * rgba_color[0] + (255*255*129 - alpha) * *(p+r_off)) >> 23; \
449 *(p+g_off) = (alpha * rgba_color[1] + (255*255*129 - alpha) * *(p+g_off)) >> 23; \
450 *(p+b_off) = (alpha * rgba_color[2] + (255*255*129 - alpha) * *(p+b_off)) >> 23; \
453 static inline int draw_glyph_rgb(AVFilterBufferRef *picref, FT_Bitmap *bitmap,
454 unsigned int x, unsigned int y,
455 unsigned int width, unsigned int height, int pixel_step,
456 const uint8_t rgba_color[4], const uint8_t rgba_map[4])
460 uint8_t src_val, dst_pixel[4];
462 for (r = 0; r < bitmap->rows && r+y < height; r++) {
463 for (c = 0; c < bitmap->width && c+x < width; c++) {
464 /* get pixel in the picref (destination) */
465 dst_pixel[0] = picref->data[0][(c+x + rgba_map[0]) * pixel_step +
466 (y+r) * picref->linesize[0]];
467 dst_pixel[1] = picref->data[0][(c+x + rgba_map[1]) * pixel_step +
468 (y+r) * picref->linesize[0]];
469 dst_pixel[2] = picref->data[0][(c+x + rgba_map[2]) * pixel_step +
470 (y+r) * picref->linesize[0]];
472 /* get intensity value in the glyph bitmap (source) */
473 src_val = GET_BITMAP_VAL(r, c);
477 SET_PIXEL_RGB(picref, rgba_color, src_val, c+x, y+r, pixel_step,
478 rgba_map[0], rgba_map[1], rgba_map[2], rgba_map[3]);
485 static inline void drawbox(AVFilterBufferRef *picref, unsigned int x, unsigned int y,
486 unsigned int width, unsigned int height,
487 uint8_t *line[4], int pixel_step[4], uint8_t color[4],
488 int hsub, int vsub, int is_rgba_packed, uint8_t rgba_map[4])
492 if (color[3] != 0xFF) {
493 if (is_rgba_packed) {
495 for (j = 0; j < height; j++)
496 for (i = 0; i < width; i++)
497 SET_PIXEL_RGB(picref, color, 255, i+x, y+j, pixel_step[0],
498 rgba_map[0], rgba_map[1], rgba_map[2], rgba_map[3]);
500 unsigned int luma_pos, chroma_pos1, chroma_pos2;
501 for (j = 0; j < height; j++)
502 for (i = 0; i < width; i++)
503 SET_PIXEL_YUV(picref, color, 255, i+x, y+j, hsub, vsub);
506 ff_draw_rectangle(picref->data, picref->linesize,
507 line, pixel_step, hsub, vsub,
508 x, y, width, height);
512 static inline int is_newline(uint32_t c)
514 return (c == '\n' || c == '\r' || c == '\f' || c == '\v');
517 static int draw_glyphs(DrawTextContext *dtext, AVFilterBufferRef *picref,
518 int width, int height, const uint8_t rgbcolor[4], const uint8_t yuvcolor[4], int x, int y)
520 char *text = dtext->text;
526 for (i = 0, p = text; *p; i++) {
528 GET_UTF8(code, *p++, continue;);
530 /* skip new line chars, just go to new line */
531 if (code == '\n' || code == '\r' || code == '\t')
535 glyph = av_tree_find(dtext->glyphs, &dummy, (void *)glyph_cmp, NULL);
537 if (glyph->bitmap.pixel_mode != FT_PIXEL_MODE_MONO &&
538 glyph->bitmap.pixel_mode != FT_PIXEL_MODE_GRAY)
539 return AVERROR(EINVAL);
541 if (dtext->is_packed_rgb) {
542 draw_glyph_rgb(picref, &glyph->bitmap,
543 dtext->positions[i].x+x, dtext->positions[i].y+y, width, height,
544 dtext->pixel_step[0], rgbcolor, dtext->rgba_map);
546 draw_glyph_yuv(picref, &glyph->bitmap,
547 dtext->positions[i].x+x, dtext->positions[i].y+y, width, height,
548 yuvcolor, dtext->hsub, dtext->vsub);
555 static int draw_text(AVFilterContext *ctx, AVFilterBufferRef *picref,
556 int width, int height)
558 DrawTextContext *dtext = ctx->priv;
559 uint32_t code = 0, prev_code = 0;
560 int x = 0, y = 0, i = 0, ret;
561 int text_height, baseline;
564 int y_min = 32000, y_max = -32000;
566 Glyph *glyph = NULL, *prev_glyph = NULL;
569 if (dtext->text != dtext->text_priv) {
571 time_t now = time(0);
574 int buflen = 2*strlen(dtext->text) + 1, len;
576 localtime_r(&now, <ime);
578 while ((buf = av_realloc(buf, buflen))) {
580 if ((len = strftime(buf, buflen, dtext->text, <ime)) != 0 || *buf == 0)
585 return AVERROR(ENOMEM);
586 av_freep(&dtext->text);
587 dtext->text = dtext->text_priv = buf;
589 dtext->text_priv = dtext->text;
591 if (!(dtext->positions = av_realloc(dtext->positions,
592 strlen(dtext->text)*sizeof(*dtext->positions))))
593 return AVERROR(ENOMEM);
599 /* load and cache glyphs */
600 for (i = 0, p = dtext->text; *p; i++) {
601 GET_UTF8(code, *p++, continue;);
605 glyph = av_tree_find(dtext->glyphs, &dummy, glyph_cmp, NULL);
607 load_glyph(ctx, &glyph, code);
609 y_min = FFMIN(glyph->bbox.yMin, y_min);
610 y_max = FFMAX(glyph->bbox.yMax, y_max);
612 text_height = y_max - y_min;
615 /* compute and save position for each glyph */
617 for (i = 0, p = dtext->text; *p; i++) {
618 GET_UTF8(code, *p++, continue;);
620 /* skip the \n in the sequence \r\n */
621 if (prev_code == '\r' && code == '\n')
625 if (is_newline(code)) {
626 str_w = FFMAX(str_w, x - dtext->x);
635 glyph = av_tree_find(dtext->glyphs, &dummy, glyph_cmp, NULL);
638 if (dtext->use_kerning && prev_glyph && glyph->code) {
639 FT_Get_Kerning(dtext->face, prev_glyph->code, glyph->code,
640 ft_kerning_default, &delta);
644 if (x + glyph->bbox.xMax >= width) {
645 str_w = FFMAX(str_w, x - dtext->x);
651 dtext->positions[i].x = x + glyph->bitmap_left;
652 dtext->positions[i].y = y - glyph->bitmap_top + baseline;
653 if (code == '\t') x = (x / dtext->tabsize + 1)*dtext->tabsize;
654 else x += glyph->advance;
657 str_w = FFMIN(width - dtext->x - 1, FFMAX(str_w, x - dtext->x));
658 y = FFMIN(y + text_height, height - 1);
662 drawbox(picref, dtext->x, dtext->y, str_w, y-dtext->y,
663 dtext->box_line, dtext->pixel_step, dtext->boxcolor,
664 dtext->hsub, dtext->vsub, dtext->is_packed_rgb, dtext->rgba_map);
666 if (dtext->shadowx || dtext->shadowy) {
667 if ((ret = draw_glyphs(dtext, picref, width, height, dtext->shadowcolor_rgba,
668 dtext->shadowcolor, dtext->shadowx, dtext->shadowy)) < 0)
672 if ((ret = draw_glyphs(dtext, picref, width, height, dtext->fontcolor_rgba,
673 dtext->fontcolor, 0, 0)) < 0)
679 static void null_draw_slice(AVFilterLink *link, int y, int h, int slice_dir) { }
681 static void end_frame(AVFilterLink *inlink)
683 AVFilterLink *outlink = inlink->dst->outputs[0];
684 AVFilterBufferRef *picref = inlink->cur_buf;
686 draw_text(inlink->dst, picref, picref->video->w, picref->video->h);
688 avfilter_draw_slice(outlink, 0, picref->video->h, 1);
689 avfilter_end_frame(outlink);
692 AVFilter avfilter_vf_drawtext = {
694 .description = NULL_IF_CONFIG_SMALL("Draw text on top of video frames using libfreetype library."),
695 .priv_size = sizeof(DrawTextContext),
698 .query_formats = query_formats,
700 .inputs = (AVFilterPad[]) {{ .name = "default",
701 .type = AVMEDIA_TYPE_VIDEO,
702 .get_video_buffer = avfilter_null_get_video_buffer,
703 .start_frame = avfilter_null_start_frame,
704 .draw_slice = null_draw_slice,
705 .end_frame = end_frame,
706 .config_props = config_input,
707 .min_perms = AV_PERM_WRITE |
709 .rej_perms = AV_PERM_PRESERVE },
711 .outputs = (AVFilterPad[]) {{ .name = "default",
712 .type = AVMEDIA_TYPE_VIDEO, },