/* * Copyright (c) 2023 Francesco Carusi * Copyright (c) 2011 Stefano Sabatini * Copyright (c) 2010 S.N. Hemanth Meenakshisundaram * Copyright (c) 2003 Gustavo Sverzut Barbieri * * This file is part of FFmpeg. * * FFmpeg is free software; you can redistribute it and/or * modify it under the terms of the GNU Lesser General Public * License as published by the Free Software Foundation; either * version 2.1 of the License, or (at your option) any later version. * * FFmpeg is distributed in the hope that it will be useful, * but WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU * Lesser General Public License for more details. * * You should have received a copy of the GNU Lesser General Public * License along with FFmpeg; if not, write to the Free Software * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA */ /** * @file * drawtext filter, based on the original vhook/drawtext.c * filter by Gustavo Sverzut Barbieri */ #include "config.h" #if HAVE_SYS_TIME_H #include #endif #include #include #include #if HAVE_UNISTD_H #include #endif #include #if CONFIG_LIBFONTCONFIG #include #endif #include "libavutil/avstring.h" #include "libavutil/bprint.h" #include "libavutil/common.h" #include "libavutil/eval.h" #include "libavutil/opt.h" #include "libavutil/random_seed.h" #include "libavutil/parseutils.h" #include "libavutil/time.h" #include "libavutil/timecode.h" #include "libavutil/time_internal.h" #include "libavutil/tree.h" #include "libavutil/lfg.h" #include "libavutil/detection_bbox.h" #include "avfilter.h" #include "drawutils.h" #include "formats.h" #include "internal.h" #include "textutils.h" #include "video.h" #if CONFIG_LIBFRIBIDI #include #endif #include #include FT_FREETYPE_H #include FT_GLYPH_H #include FT_STROKER_H #include #include // Ceiling operation for positive integers division #define POS_CEIL(x, y) ((x)/(y) + ((x)%(y) != 0)) static const char *const var_names[] = { "dar", "hsub", "vsub", "line_h", "lh", ///< line height "main_h", "h", "H", ///< height of the input video "main_w", "w", "W", ///< width of the input video "max_glyph_a", "ascent", ///< max glyph ascender "max_glyph_d", "descent", ///< min glyph descender "max_glyph_h", ///< max glyph height "max_glyph_w", ///< max glyph width "font_a", ///< font-defined ascent "font_d", ///< font-defined descent "top_a", ///< max glyph ascender of the top line "bottom_d", ///< max glyph descender of the bottom line "n", ///< number of frame "sar", "t", ///< timestamp expressed in seconds "text_h", "th", ///< height of the rendered text "text_w", "tw", ///< width of the rendered text "x", "y", "pict_type", #if FF_API_FRAME_PKT "pkt_pos", #endif #if FF_API_FRAME_PKT "pkt_size", #endif "duration", NULL }; static const char *const fun2_names[] = { "rand" }; static double drand(void *opaque, double min, double max) { return min + (max-min) / UINT_MAX * av_lfg_get(opaque); } typedef double (*eval_func2)(void *, double a, double b); static const eval_func2 fun2[] = { drand, NULL }; enum var_name { VAR_DAR, VAR_HSUB, VAR_VSUB, VAR_LINE_H, VAR_LH, VAR_MAIN_H, VAR_h, VAR_H, VAR_MAIN_W, VAR_w, VAR_W, VAR_MAX_GLYPH_A, VAR_ASCENT, VAR_MAX_GLYPH_D, VAR_DESCENT, VAR_MAX_GLYPH_H, VAR_MAX_GLYPH_W, VAR_FONT_A, VAR_FONT_D, VAR_TOP_A, VAR_BOTTOM_D, VAR_N, VAR_SAR, VAR_T, VAR_TEXT_H, VAR_TH, VAR_TEXT_W, VAR_TW, VAR_X, VAR_Y, VAR_PICT_TYPE, #if FF_API_FRAME_PKT VAR_PKT_POS, #endif #if FF_API_FRAME_PKT VAR_PKT_SIZE, #endif VAR_DURATION, VAR_VARS_NB }; enum expansion_mode { EXP_NONE, EXP_NORMAL, EXP_STRFTIME, }; enum y_alignment { YA_TEXT, YA_BASELINE, YA_FONT, }; enum text_alignment { TA_LEFT = (1 << 0), TA_RIGHT = (1 << 1), TA_TOP = (1 << 2), TA_BOTTOM = (1 << 3), }; typedef struct HarfbuzzData { hb_buffer_t* buf; hb_font_t* font; unsigned int glyph_count; hb_glyph_info_t* glyph_info; hb_glyph_position_t* glyph_pos; } HarfbuzzData; /** Information about a single glyph in a text line */ typedef struct GlyphInfo { uint32_t code; ///< the glyph code point int x; ///< the x position of the glyph int y; ///< the y position of the glyph int shift_x64; ///< the horizontal shift of the glyph in 26.6 units int shift_y64; ///< the vertical shift of the glyph in 26.6 units } GlyphInfo; /** Information about a single line of text */ typedef struct TextLine { int offset_left64; ///< offset between the origin and /// the leftmost pixel of the first glyph int offset_right64; ///< maximum offset between the origin and /// the rightmost pixel of the last glyph int width64; ///< width of the line HarfbuzzData hb_data; ///< libharfbuzz data of this text line GlyphInfo* glyphs; ///< array of glyphs in this text line int cluster_offset; ///< the offset at which this line begins } TextLine; /** A glyph as loaded and rendered using libfreetype */ typedef struct Glyph { FT_Glyph glyph; FT_Glyph border_glyph; uint32_t code; unsigned int fontsize; /** Glyph bitmaps with 1/4 pixel precision in both directions */ FT_BitmapGlyph bglyph[16]; /** Outlined glyph bitmaps with 1/4 pixel precision in both directions */ FT_BitmapGlyph border_bglyph[16]; FT_BBox bbox; } Glyph; /** Global text metrics */ typedef struct TextMetrics { int offset_top64; ///< ascender amount of the first line (in 26.6 units) int offset_bottom64; ///< descender amount of the last line (in 26.6 units) int offset_left64; ///< maximum offset between the origin and /// the leftmost pixel of the first glyph /// of each line (in 26.6 units) int offset_right64; ///< maximum offset between the origin and /// the rightmost pixel of the last glyph /// of each line (in 26.6 units) int line_height64; ///< the font-defined line height int width; ///< width of the longest line - ceil(width64/64) int height; ///< total height of the text - ceil(height64/64) int min_y64; ///< minimum value of bbox.yMin among glyphs (in 26.6 units) int max_y64; ///< maximum value of bbox.yMax among glyphs (in 26.6 units) int min_x64; ///< minimum value of bbox.xMin among glyphs (in 26.6 units) int max_x64; ///< maximum value of bbox.xMax among glyphs (in 26.6 units) // Position of the background box (without borders) int rect_x; ///< x position of the box int rect_y; ///< y position of the box } TextMetrics; typedef struct DrawTextContext { const AVClass *class; int exp_mode; ///< expansion mode to use for the text FFExpandTextContext expand_text; ///< expand text in case exp_mode == NORMAL int reinit; ///< tells if the filter is being reinited #if CONFIG_LIBFONTCONFIG uint8_t *font; ///< font to be used #endif uint8_t *fontfile; ///< font to be used uint8_t *text; ///< text to be drawn AVBPrint expanded_text; ///< used to contain the expanded text uint8_t *fontcolor_expr; ///< fontcolor expression to evaluate AVBPrint expanded_fontcolor; ///< used to contain the expanded fontcolor spec int ft_load_flags; ///< flags used for loading fonts, see FT_LOAD_* char *textfile; ///< file with text to be drawn double x; ///< x position to start drawing text double y; ///< y position to start drawing text int max_glyph_w; ///< max glyph width int max_glyph_h; ///< max glyph height int shadowx, shadowy; int borderw; ///< border width char *fontsize_expr; ///< expression for fontsize AVExpr *fontsize_pexpr; ///< parsed expressions for fontsize unsigned int fontsize; ///< font size to use unsigned int default_fontsize; ///< default font size to use int line_spacing; ///< lines spacing in pixels short int draw_box; ///< draw box around text - true or false char *boxborderw; ///< box border width (padding) /// allowed formats: "all", "vert|oriz", "top|right|bottom|left" int bb_top; ///< the size of the top box border int bb_right; ///< the size of the right box border int bb_bottom; ///< the size of the bottom box border int bb_left; ///< the size of the left box border int box_width; ///< the width of box int box_height; ///< the height of box int tabsize; ///< tab size int fix_bounds; ///< do we let it go out of frame bounds - t/f FFDrawContext dc; FFDrawColor fontcolor; ///< foreground color FFDrawColor shadowcolor; ///< shadow color FFDrawColor bordercolor; ///< border color FFDrawColor boxcolor; ///< background color FT_Library library; ///< freetype font library handle FT_Face face; ///< freetype font face handle FT_Stroker stroker; ///< freetype stroker handle struct AVTreeNode *glyphs; ///< rendered glyphs, stored using the UTF-32 char code char *x_expr; ///< expression for x position char *y_expr; ///< expression for y position AVExpr *x_pexpr, *y_pexpr; ///< parsed expressions for x and y int64_t basetime; ///< base pts time in the real world for display double var_values[VAR_VARS_NB]; char *a_expr; AVExpr *a_pexpr; int alpha; AVLFG prng; ///< random char *tc_opt_string; ///< specified timecode option string AVRational tc_rate; ///< frame rate for timecode AVTimecode tc; ///< timecode context int tc24hmax; ///< 1 if timecode is wrapped to 24 hours, 0 otherwise int reload; ///< reload text file at specified frame interval int start_number; ///< starting frame number for n/frame_num var char *text_source_string; ///< the string to specify text data source enum AVFrameSideDataType text_source; #if CONFIG_LIBFRIBIDI int text_shaping; ///< 1 to shape the text before drawing it #endif AVDictionary *metadata; int boxw; ///< the value of the boxw parameter int boxh; ///< the value of the boxh parameter int text_align; ///< the horizontal and vertical text alignment int y_align; ///< the value of the y_align parameter TextLine *lines; ///< computed information about text lines int line_count; ///< the number of text lines uint32_t *tab_clusters; ///< the position of tab characters in the text int tab_count; ///< the number of tab characters int blank_advance64; ///< the size of the space character int tab_warning_printed; ///< ensure the tab warning to be printed only once } DrawTextContext; #define OFFSET(x) offsetof(DrawTextContext, x) #define FLAGS AV_OPT_FLAG_FILTERING_PARAM|AV_OPT_FLAG_VIDEO_PARAM #define TFLAGS AV_OPT_FLAG_FILTERING_PARAM|AV_OPT_FLAG_VIDEO_PARAM|AV_OPT_FLAG_RUNTIME_PARAM static const AVOption drawtext_options[]= { {"fontfile", "set font file", OFFSET(fontfile), AV_OPT_TYPE_STRING, {.str=NULL}, 0, 0, FLAGS}, {"text", "set text", OFFSET(text), AV_OPT_TYPE_STRING, {.str=NULL}, 0, 0, TFLAGS}, {"textfile", "set text file", OFFSET(textfile), AV_OPT_TYPE_STRING, {.str=NULL}, 0, 0, FLAGS}, {"fontcolor", "set foreground color", OFFSET(fontcolor.rgba), AV_OPT_TYPE_COLOR, {.str="black"}, 0, 0, TFLAGS}, {"fontcolor_expr", "set foreground color expression", OFFSET(fontcolor_expr), AV_OPT_TYPE_STRING, {.str=""}, 0, 0, FLAGS}, {"boxcolor", "set box color", OFFSET(boxcolor.rgba), AV_OPT_TYPE_COLOR, {.str="white"}, 0, 0, TFLAGS}, {"bordercolor", "set border color", OFFSET(bordercolor.rgba), AV_OPT_TYPE_COLOR, {.str="black"}, 0, 0, TFLAGS}, {"shadowcolor", "set shadow color", OFFSET(shadowcolor.rgba), AV_OPT_TYPE_COLOR, {.str="black"}, 0, 0, TFLAGS}, {"box", "set box", OFFSET(draw_box), AV_OPT_TYPE_BOOL, {.i64=0}, 0, 1, TFLAGS}, {"boxborderw", "set box borders width", OFFSET(boxborderw), AV_OPT_TYPE_STRING, {.str="0"}, 0, 0, TFLAGS}, {"line_spacing", "set line spacing in pixels", OFFSET(line_spacing), AV_OPT_TYPE_INT, {.i64=0}, INT_MIN, INT_MAX, TFLAGS}, {"fontsize", "set font size", OFFSET(fontsize_expr), AV_OPT_TYPE_STRING, {.str=NULL}, 0, 0, TFLAGS}, {"text_align", "set text alignment", OFFSET(text_align), AV_OPT_TYPE_FLAGS, {.i64=0}, 0, (TA_LEFT|TA_RIGHT|TA_TOP|TA_BOTTOM), TFLAGS, .unit = "text_align"}, { "left", NULL, 0, AV_OPT_TYPE_CONST, { .i64 = TA_LEFT }, .flags = TFLAGS, .unit = "text_align" }, { "L", NULL, 0, AV_OPT_TYPE_CONST, { .i64 = TA_LEFT }, .flags = TFLAGS, .unit = "text_align" }, { "right", NULL, 0, AV_OPT_TYPE_CONST, { .i64 = TA_RIGHT }, .flags = TFLAGS, .unit = "text_align" }, { "R", NULL, 0, AV_OPT_TYPE_CONST, { .i64 = TA_RIGHT }, .flags = TFLAGS, .unit = "text_align" }, { "center", NULL, 0, AV_OPT_TYPE_CONST, { .i64 = (TA_LEFT|TA_RIGHT) }, .flags = TFLAGS, .unit = "text_align" }, { "C", NULL, 0, AV_OPT_TYPE_CONST, { .i64 = (TA_LEFT|TA_RIGHT) }, .flags = TFLAGS, .unit = "text_align" }, { "top", NULL, 0, AV_OPT_TYPE_CONST, { .i64 = TA_TOP }, .flags = TFLAGS, .unit = "text_align" }, { "T", NULL, 0, AV_OPT_TYPE_CONST, { .i64 = TA_TOP }, .flags = TFLAGS, .unit = "text_align" }, { "bottom", NULL, 0, AV_OPT_TYPE_CONST, { .i64 = TA_BOTTOM }, .flags = TFLAGS, .unit = "text_align" }, { "B", NULL, 0, AV_OPT_TYPE_CONST, { .i64 = TA_BOTTOM }, .flags = TFLAGS, .unit = "text_align" }, { "middle", NULL, 0, AV_OPT_TYPE_CONST, { .i64 = (TA_TOP|TA_BOTTOM) }, .flags = TFLAGS, .unit = "text_align" }, { "M", NULL, 0, AV_OPT_TYPE_CONST, { .i64 = (TA_TOP|TA_BOTTOM) }, .flags = TFLAGS, .unit = "text_align" }, {"x", "set x expression", OFFSET(x_expr), AV_OPT_TYPE_STRING, {.str="0"}, 0, 0, TFLAGS}, {"y", "set y expression", OFFSET(y_expr), AV_OPT_TYPE_STRING, {.str="0"}, 0, 0, TFLAGS}, {"boxw", "set box width", OFFSET(boxw), AV_OPT_TYPE_INT, {.i64=0}, 0, INT_MAX, TFLAGS}, {"boxh", "set box height", OFFSET(boxh), AV_OPT_TYPE_INT, {.i64=0}, 0, INT_MAX, TFLAGS}, {"shadowx", "set shadow x offset", OFFSET(shadowx), AV_OPT_TYPE_INT, {.i64=0}, INT_MIN, INT_MAX, TFLAGS}, {"shadowy", "set shadow y offset", OFFSET(shadowy), AV_OPT_TYPE_INT, {.i64=0}, INT_MIN, INT_MAX, TFLAGS}, {"borderw", "set border width", OFFSET(borderw), AV_OPT_TYPE_INT, {.i64=0}, INT_MIN, INT_MAX, TFLAGS}, {"tabsize", "set tab size", OFFSET(tabsize), AV_OPT_TYPE_INT, {.i64=4}, 0, INT_MAX, TFLAGS}, {"basetime", "set base time", OFFSET(basetime), AV_OPT_TYPE_INT64, {.i64=AV_NOPTS_VALUE}, INT64_MIN, INT64_MAX, FLAGS}, #if CONFIG_LIBFONTCONFIG { "font", "Font name", OFFSET(font), AV_OPT_TYPE_STRING, { .str = "Sans" }, .flags = FLAGS }, #endif {"expansion", "set the expansion mode", OFFSET(exp_mode), AV_OPT_TYPE_INT, {.i64=EXP_NORMAL}, 0, 2, FLAGS, .unit = "expansion"}, {"none", "set no expansion", OFFSET(exp_mode), AV_OPT_TYPE_CONST, {.i64=EXP_NONE}, 0, 0, FLAGS, .unit = "expansion"}, {"normal", "set normal expansion", OFFSET(exp_mode), AV_OPT_TYPE_CONST, {.i64=EXP_NORMAL}, 0, 0, FLAGS, .unit = "expansion"}, {"strftime", "set strftime expansion (deprecated)", OFFSET(exp_mode), AV_OPT_TYPE_CONST, {.i64=EXP_STRFTIME}, 0, 0, FLAGS, .unit = "expansion"}, {"y_align", "set the y alignment", OFFSET(y_align), AV_OPT_TYPE_INT, {.i64=YA_TEXT}, 0, 2, TFLAGS, .unit = "y_align"}, {"text", "y is referred to the top of the first text line", OFFSET(y_align), AV_OPT_TYPE_CONST, {.i64=YA_TEXT}, 0, 0, FLAGS, .unit = "y_align"}, {"baseline", "y is referred to the baseline of the first line", OFFSET(y_align), AV_OPT_TYPE_CONST, {.i64=YA_BASELINE}, 0, 0, FLAGS, .unit = "y_align"}, {"font", "y is referred to the font defined line metrics", OFFSET(y_align), AV_OPT_TYPE_CONST, {.i64=YA_FONT}, 0, 0, FLAGS, .unit = "y_align"}, {"timecode", "set initial timecode", OFFSET(tc_opt_string), AV_OPT_TYPE_STRING, {.str=NULL}, 0, 0, FLAGS}, {"tc24hmax", "set 24 hours max (timecode only)", OFFSET(tc24hmax), AV_OPT_TYPE_BOOL, {.i64=0}, 0, 1, FLAGS}, {"timecode_rate", "set rate (timecode only)", OFFSET(tc_rate), AV_OPT_TYPE_RATIONAL, {.dbl=0}, 0, INT_MAX, FLAGS}, {"r", "set rate (timecode only)", OFFSET(tc_rate), AV_OPT_TYPE_RATIONAL, {.dbl=0}, 0, INT_MAX, FLAGS}, {"rate", "set rate (timecode only)", OFFSET(tc_rate), AV_OPT_TYPE_RATIONAL, {.dbl=0}, 0, INT_MAX, FLAGS}, {"reload", "reload text file at specified frame interval", OFFSET(reload), AV_OPT_TYPE_INT, {.i64=0}, 0, INT_MAX, FLAGS}, {"alpha", "apply alpha while rendering", OFFSET(a_expr), AV_OPT_TYPE_STRING, {.str = "1"}, .flags = TFLAGS}, {"fix_bounds", "check and fix text coords to avoid clipping", OFFSET(fix_bounds), AV_OPT_TYPE_BOOL, {.i64=0}, 0, 1, FLAGS}, {"start_number", "start frame number for n/frame_num variable", OFFSET(start_number), AV_OPT_TYPE_INT, {.i64=0}, 0, INT_MAX, FLAGS}, {"text_source", "the source of text", OFFSET(text_source_string), AV_OPT_TYPE_STRING, {.str=NULL}, 0, 1, FLAGS }, #if CONFIG_LIBFRIBIDI {"text_shaping", "attempt to shape text before drawing", OFFSET(text_shaping), AV_OPT_TYPE_BOOL, {.i64=1}, 0, 1, FLAGS}, #endif /* FT_LOAD_* flags */ { "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, .unit = "ft_load_flags" }, { "default", NULL, 0, AV_OPT_TYPE_CONST, { .i64 = FT_LOAD_DEFAULT }, .flags = FLAGS, .unit = "ft_load_flags" }, { "no_scale", NULL, 0, AV_OPT_TYPE_CONST, { .i64 = FT_LOAD_NO_SCALE }, .flags = FLAGS, .unit = "ft_load_flags" }, { "no_hinting", NULL, 0, AV_OPT_TYPE_CONST, { .i64 = FT_LOAD_NO_HINTING }, .flags = FLAGS, .unit = "ft_load_flags" }, { "render", NULL, 0, AV_OPT_TYPE_CONST, { .i64 = FT_LOAD_RENDER }, .flags = FLAGS, .unit = "ft_load_flags" }, { "no_bitmap", NULL, 0, AV_OPT_TYPE_CONST, { .i64 = FT_LOAD_NO_BITMAP }, .flags = FLAGS, .unit = "ft_load_flags" }, { "vertical_layout", NULL, 0, AV_OPT_TYPE_CONST, { .i64 = FT_LOAD_VERTICAL_LAYOUT }, .flags = FLAGS, .unit = "ft_load_flags" }, { "force_autohint", NULL, 0, AV_OPT_TYPE_CONST, { .i64 = FT_LOAD_FORCE_AUTOHINT }, .flags = FLAGS, .unit = "ft_load_flags" }, { "crop_bitmap", NULL, 0, AV_OPT_TYPE_CONST, { .i64 = FT_LOAD_CROP_BITMAP }, .flags = FLAGS, .unit = "ft_load_flags" }, { "pedantic", NULL, 0, AV_OPT_TYPE_CONST, { .i64 = FT_LOAD_PEDANTIC }, .flags = FLAGS, .unit = "ft_load_flags" }, { "ignore_global_advance_width", NULL, 0, AV_OPT_TYPE_CONST, { .i64 = FT_LOAD_IGNORE_GLOBAL_ADVANCE_WIDTH }, .flags = FLAGS, .unit = "ft_load_flags" }, { "no_recurse", NULL, 0, AV_OPT_TYPE_CONST, { .i64 = FT_LOAD_NO_RECURSE }, .flags = FLAGS, .unit = "ft_load_flags" }, { "ignore_transform", NULL, 0, AV_OPT_TYPE_CONST, { .i64 = FT_LOAD_IGNORE_TRANSFORM }, .flags = FLAGS, .unit = "ft_load_flags" }, { "monochrome", NULL, 0, AV_OPT_TYPE_CONST, { .i64 = FT_LOAD_MONOCHROME }, .flags = FLAGS, .unit = "ft_load_flags" }, { "linear_design", NULL, 0, AV_OPT_TYPE_CONST, { .i64 = FT_LOAD_LINEAR_DESIGN }, .flags = FLAGS, .unit = "ft_load_flags" }, { "no_autohint", NULL, 0, AV_OPT_TYPE_CONST, { .i64 = FT_LOAD_NO_AUTOHINT }, .flags = FLAGS, .unit = "ft_load_flags" }, { NULL } }; AVFILTER_DEFINE_CLASS(drawtext); #undef __FTERRORS_H__ #define FT_ERROR_START_LIST { #define FT_ERRORDEF(e, v, s) { (e), (s) }, #define FT_ERROR_END_LIST { 0, NULL } }; static const struct ft_error { int err; const char *err_msg; } ft_errors[] = #include FT_ERRORS_H #define FT_ERRMSG(e) ft_errors[e].err_msg static int glyph_cmp(const void *key, const void *b) { const Glyph *a = key, *bb = b; int64_t diff = (int64_t)a->code - (int64_t)bb->code; if (diff != 0) return diff > 0 ? 1 : -1; else return FFDIFFSIGN((int64_t)a->fontsize, (int64_t)bb->fontsize); } static av_cold int set_fontsize(AVFilterContext *ctx, unsigned int fontsize) { int err; DrawTextContext *s = ctx->priv; if ((err = FT_Set_Pixel_Sizes(s->face, 0, fontsize))) { av_log(ctx, AV_LOG_ERROR, "Could not set font size to %d pixels: %s\n", fontsize, FT_ERRMSG(err)); return AVERROR(EINVAL); } s->fontsize = fontsize; return 0; } static av_cold int parse_fontsize(AVFilterContext *ctx) { DrawTextContext *s = ctx->priv; int err; if (s->fontsize_pexpr) return 0; if (s->fontsize_expr == NULL) return AVERROR(EINVAL); if ((err = av_expr_parse(&s->fontsize_pexpr, s->fontsize_expr, var_names, NULL, NULL, fun2_names, fun2, 0, ctx)) < 0) return err; return 0; } static av_cold int update_fontsize(AVFilterContext *ctx) { DrawTextContext *s = ctx->priv; unsigned int fontsize = s->default_fontsize; int err; double size, roundedsize; // if no fontsize specified use the default if (s->fontsize_expr != NULL) { if ((err = parse_fontsize(ctx)) < 0) return err; size = av_expr_eval(s->fontsize_pexpr, s->var_values, &s->prng); if (!isnan(size)) { roundedsize = round(size); // test for overflow before cast if (!(roundedsize > INT_MIN && roundedsize < INT_MAX)) { av_log(ctx, AV_LOG_ERROR, "fontsize overflow\n"); return AVERROR(EINVAL); } fontsize = roundedsize; } } if (fontsize == 0) fontsize = 1; // no change if (fontsize == s->fontsize) return 0; return set_fontsize(ctx, fontsize); } static int load_font_file(AVFilterContext *ctx, const char *path, int index) { DrawTextContext *s = ctx->priv; int err; err = FT_New_Face(s->library, path, index, &s->face); if (err) { #if !CONFIG_LIBFONTCONFIG av_log(ctx, AV_LOG_ERROR, "Could not load font \"%s\": %s\n", s->fontfile, FT_ERRMSG(err)); #endif return AVERROR(EINVAL); } return 0; } #if CONFIG_LIBFONTCONFIG static int load_font_fontconfig(AVFilterContext *ctx) { DrawTextContext *s = ctx->priv; FcConfig *fontconfig; FcPattern *pat, *best; FcResult result = FcResultMatch; FcChar8 *filename; int index; double size; int err = AVERROR(ENOENT); int parse_err; fontconfig = FcInitLoadConfigAndFonts(); if (!fontconfig) { av_log(ctx, AV_LOG_ERROR, "impossible to init fontconfig\n"); return AVERROR_UNKNOWN; } pat = FcNameParse(s->fontfile ? s->fontfile : (uint8_t *)(intptr_t)"default"); if (!pat) { av_log(ctx, AV_LOG_ERROR, "could not parse fontconfig pat"); return AVERROR(EINVAL); } FcPatternAddString(pat, FC_FAMILY, s->font); parse_err = parse_fontsize(ctx); if (!parse_err) { double size = av_expr_eval(s->fontsize_pexpr, s->var_values, &s->prng); if (isnan(size)) { av_log(ctx, AV_LOG_ERROR, "impossible to find font information"); return AVERROR(EINVAL); } FcPatternAddDouble(pat, FC_SIZE, size); } FcDefaultSubstitute(pat); if (!FcConfigSubstitute(fontconfig, pat, FcMatchPattern)) { av_log(ctx, AV_LOG_ERROR, "could not substitue fontconfig options"); /* very unlikely */ FcPatternDestroy(pat); return AVERROR(ENOMEM); } best = FcFontMatch(fontconfig, pat, &result); FcPatternDestroy(pat); if (!best || result != FcResultMatch) { av_log(ctx, AV_LOG_ERROR, "Cannot find a valid font for the family %s\n", s->font); goto fail; } if ( FcPatternGetInteger(best, FC_INDEX, 0, &index ) != FcResultMatch || FcPatternGetDouble (best, FC_SIZE, 0, &size ) != FcResultMatch) { av_log(ctx, AV_LOG_ERROR, "impossible to find font information"); return AVERROR(EINVAL); } if (FcPatternGetString(best, FC_FILE, 0, &filename) != FcResultMatch) { av_log(ctx, AV_LOG_ERROR, "No file path for %s\n", s->font); goto fail; } av_log(ctx, AV_LOG_VERBOSE, "Using \"%s\"\n", filename); if (parse_err) s->default_fontsize = size + 0.5; err = load_font_file(ctx, filename, index); if (err) return err; FcConfigDestroy(fontconfig); fail: FcPatternDestroy(best); return err; } #endif static int load_font(AVFilterContext *ctx) { DrawTextContext *s = ctx->priv; int err; /* load the face, and set up the encoding, which is by default UTF-8 */ err = load_font_file(ctx, s->fontfile, 0); if (!err) return 0; #if CONFIG_LIBFONTCONFIG err = load_font_fontconfig(ctx); if (!err) return 0; #endif return err; } #if CONFIG_LIBFRIBIDI static int shape_text(AVFilterContext *ctx) { DrawTextContext *s = ctx->priv; uint8_t *tmp; int ret = AVERROR(ENOMEM); static const FriBidiFlags flags = FRIBIDI_FLAGS_DEFAULT | FRIBIDI_FLAGS_ARABIC; FriBidiChar *unicodestr = NULL; FriBidiStrIndex len; FriBidiParType direction = FRIBIDI_PAR_LTR; FriBidiStrIndex line_start = 0; FriBidiStrIndex line_end = 0; FriBidiLevel *embedding_levels = NULL; FriBidiArabicProp *ar_props = NULL; FriBidiCharType *bidi_types = NULL; FriBidiStrIndex i,j; len = strlen(s->text); if (!(unicodestr = av_malloc_array(len, sizeof(*unicodestr)))) { goto out; } len = fribidi_charset_to_unicode(FRIBIDI_CHAR_SET_UTF8, s->text, len, unicodestr); bidi_types = av_malloc_array(len, sizeof(*bidi_types)); if (!bidi_types) { goto out; } fribidi_get_bidi_types(unicodestr, len, bidi_types); embedding_levels = av_malloc_array(len, sizeof(*embedding_levels)); if (!embedding_levels) { goto out; } if (!fribidi_get_par_embedding_levels(bidi_types, len, &direction, embedding_levels)) { goto out; } ar_props = av_malloc_array(len, sizeof(*ar_props)); if (!ar_props) { goto out; } fribidi_get_joining_types(unicodestr, len, ar_props); fribidi_join_arabic(bidi_types, len, embedding_levels, ar_props); fribidi_shape(flags, embedding_levels, len, ar_props, unicodestr); for (line_end = 0, line_start = 0; line_end < len; line_end++) { if (ff_is_newline(unicodestr[line_end]) || line_end == len - 1) { if (!fribidi_reorder_line(flags, bidi_types, line_end - line_start + 1, line_start, direction, embedding_levels, unicodestr, NULL)) { goto out; } line_start = line_end + 1; } } /* Remove zero-width fill chars put in by libfribidi */ for (i = 0, j = 0; i < len; i++) if (unicodestr[i] != FRIBIDI_CHAR_FILL) unicodestr[j++] = unicodestr[i]; len = j; if (!(tmp = av_realloc(s->text, (len * 4 + 1) * sizeof(*s->text)))) { /* Use len * 4, as a unicode character can be up to 4 bytes in UTF-8 */ goto out; } s->text = tmp; len = fribidi_unicode_to_charset(FRIBIDI_CHAR_SET_UTF8, unicodestr, len, s->text); ret = 0; out: av_free(unicodestr); av_free(embedding_levels); av_free(ar_props); av_free(bidi_types); return ret; } #endif static enum AVFrameSideDataType text_source_string_parse(const char *text_source_string) { av_assert0(text_source_string); if (!strcmp(text_source_string, "side_data_detection_bboxes")) { return AV_FRAME_DATA_DETECTION_BBOXES; } else { return AVERROR(EINVAL); } } static inline int get_subpixel_idx(int shift_x64, int shift_y64) { int idx = (shift_x64 >> 2) + (shift_y64 >> 4); return idx; } // Loads and (optionally) renders a glyph static int load_glyph(AVFilterContext *ctx, Glyph **glyph_ptr, uint32_t code, int8_t shift_x64, int8_t shift_y64) { DrawTextContext *s = ctx->priv; Glyph dummy = { 0 }; Glyph *glyph; FT_Vector shift; struct AVTreeNode *node = NULL; int ret = 0; /* get glyph */ dummy.code = code; dummy.fontsize = s->fontsize; glyph = av_tree_find(s->glyphs, &dummy, glyph_cmp, NULL); if (!glyph) { if (FT_Load_Glyph(s->face, code, s->ft_load_flags)) { return AVERROR(EINVAL); } glyph = av_mallocz(sizeof(*glyph)); if (!glyph) { ret = AVERROR(ENOMEM); goto error; } glyph->code = code; glyph->fontsize = s->fontsize; if (FT_Get_Glyph(s->face->glyph, &glyph->glyph)) { ret = AVERROR(EINVAL); goto error; } if (s->borderw) { glyph->border_glyph = glyph->glyph; if (FT_Glyph_StrokeBorder(&glyph->border_glyph, s->stroker, 0, 0)) { ret = AVERROR_EXTERNAL; goto error; } } /* measure text height to calculate text_height (or the maximum text height) */ FT_Glyph_Get_CBox(glyph->glyph, FT_GLYPH_BBOX_SUBPIXELS, &glyph->bbox); /* cache the newly created glyph */ if (!(node = av_tree_node_alloc())) { ret = AVERROR(ENOMEM); goto error; } av_tree_insert(&s->glyphs, glyph, glyph_cmp, &node); } else { if (s->borderw && !glyph->border_glyph) { glyph->border_glyph = glyph->glyph; if (FT_Glyph_StrokeBorder(&glyph->border_glyph, s->stroker, 0, 0)) { ret = AVERROR_EXTERNAL; goto error; } } } // Check if a bitmap is needed if (shift_x64 >= 0 && shift_y64 >= 0) { // Get the bitmap subpixel index (0 -> 15) int idx = get_subpixel_idx(shift_x64, shift_y64); shift.x = shift_x64; shift.y = shift_y64; if (!glyph->bglyph[idx]) { FT_Glyph tmp_glyph = glyph->glyph; if (FT_Glyph_To_Bitmap(&tmp_glyph, FT_RENDER_MODE_NORMAL, &shift, 0)) { ret = AVERROR_EXTERNAL; goto error; } glyph->bglyph[idx] = (FT_BitmapGlyph)tmp_glyph; if (glyph->bglyph[idx]->bitmap.pixel_mode == FT_PIXEL_MODE_MONO) { av_log(ctx, AV_LOG_ERROR, "Monocromatic (1bpp) fonts are not supported.\n"); ret = AVERROR(EINVAL); goto error; } } if (s->borderw && !glyph->border_bglyph[idx]) { FT_Glyph tmp_glyph = glyph->border_glyph; if (FT_Glyph_To_Bitmap(&tmp_glyph, FT_RENDER_MODE_NORMAL, &shift, 0)) { ret = AVERROR_EXTERNAL; goto error; } glyph->border_bglyph[idx] = (FT_BitmapGlyph)tmp_glyph; } } if (glyph_ptr) { *glyph_ptr = glyph; } return 0; error: if (glyph && glyph->glyph) FT_Done_Glyph(glyph->glyph); av_freep(&glyph); av_freep(&node); return ret; } // Convert a string formatted as "n1|n2|...|nN" into an integer array static int string_to_array(const char *source, int *result, int result_size) { int counter = 0, size = strlen(source) + 1; char *saveptr, *curval, *dup = av_malloc(size); if (!dup) return 0; av_strlcpy(dup, source, size); if (result_size > 0 && (curval = av_strtok(dup, "|", &saveptr))) { do { result[counter++] = atoi(curval); } while ((curval = av_strtok(NULL, "|", &saveptr)) && counter < result_size); } av_free(dup); return counter; } static int func_pict_type(void *ctx, AVBPrint *bp, const char *function_name, unsigned argc, char **argv) { DrawTextContext *s = ((AVFilterContext *)ctx)->priv; av_bprintf(bp, "%c", av_get_picture_type_char(s->var_values[VAR_PICT_TYPE])); return 0; } static int func_pts(void *ctx, AVBPrint *bp, const char *function_name, unsigned argc, char **argv) { DrawTextContext *s = ((AVFilterContext *)ctx)->priv; const char *fmt; const char *strftime_fmt = NULL; const char *delta = NULL; double pts = s->var_values[VAR_T]; // argv: pts, FMT, [DELTA, 24HH | strftime_fmt] fmt = argc >= 1 ? argv[0] : "flt"; if (argc >= 2) { delta = argv[1]; } if (argc >= 3) { if (!strcmp(fmt, "hms")) { if (!strcmp(argv[2], "24HH")) { av_log(ctx, AV_LOG_WARNING, "pts third argument 24HH is deprected, use pts:hms24hh instead\n"); fmt = "hms24"; } else { av_log(ctx, AV_LOG_ERROR, "Invalid argument '%s', '24HH' was expected\n", argv[2]); return AVERROR(EINVAL); } } else { strftime_fmt = argv[2]; } } return ff_print_pts(ctx, bp, pts, delta, fmt, strftime_fmt); } static int func_frame_num(void *ctx, AVBPrint *bp, const char *function_name, unsigned argc, char **argv) { DrawTextContext *s = ((AVFilterContext *)ctx)->priv; av_bprintf(bp, "%d", (int)s->var_values[VAR_N]); return 0; } static int func_metadata(void *ctx, AVBPrint *bp, const char *function_name, unsigned argc, char **argv) { DrawTextContext *s = ((AVFilterContext *)ctx)->priv; AVDictionaryEntry *e = av_dict_get(s->metadata, argv[0], NULL, 0); if (e && e->value) av_bprintf(bp, "%s", e->value); else if (argc >= 2) av_bprintf(bp, "%s", argv[1]); return 0; } static int func_strftime(void *ctx, AVBPrint *bp, const char *function_name, unsigned argc, char **argv) { const char *strftime_fmt = argc ? argv[0] : NULL; return ff_print_time(ctx, bp, strftime_fmt, !strcmp(function_name, "localtime")); } static int func_eval_expr(void *ctx, AVBPrint *bp, const char *function_name, unsigned argc, char **argv) { DrawTextContext *s = ((AVFilterContext *)ctx)->priv; return ff_print_eval_expr(ctx, bp, argv[0], fun2_names, fun2, var_names, s->var_values, &s->prng); } static int func_eval_expr_int_format(void *ctx, AVBPrint *bp, const char *function_name, unsigned argc, char **argv) { DrawTextContext *s = ((AVFilterContext *)ctx)->priv; int ret; int positions = -1; /* * argv[0] expression to be converted to `int` * argv[1] format: 'x', 'X', 'd' or 'u' * argv[2] positions printed (optional) */ if (argc == 3) { ret = sscanf(argv[2], "%u", &positions); if (ret != 1) { av_log(ctx, AV_LOG_ERROR, "expr_int_format(): Invalid number of positions" " to print: '%s'\n", argv[2]); return AVERROR(EINVAL); } } return ff_print_formatted_eval_expr(ctx, bp, argv[0], fun2_names, fun2, var_names, s->var_values, &s->prng, argv[1][0], positions); } static FFExpandTextFunction expand_text_functions[] = { { "e", 1, 1, func_eval_expr }, { "eif", 2, 3, func_eval_expr_int_format }, { "expr", 1, 1, func_eval_expr }, { "expr_int_format", 2, 3, func_eval_expr_int_format }, { "frame_num", 0, 0, func_frame_num }, { "gmtime", 0, 1, func_strftime }, { "localtime", 0, 1, func_strftime }, { "metadata", 1, 2, func_metadata }, { "n", 0, 0, func_frame_num }, { "pict_type", 0, 0, func_pict_type }, { "pts", 0, 3, func_pts } }; static av_cold int init(AVFilterContext *ctx) { int err; DrawTextContext *s = ctx->priv; av_expr_free(s->fontsize_pexpr); s->fontsize_pexpr = NULL; s->fontsize = 0; s->default_fontsize = 16; if (!s->fontfile && !CONFIG_LIBFONTCONFIG) { av_log(ctx, AV_LOG_ERROR, "No font filename provided\n"); return AVERROR(EINVAL); } if (s->textfile) { if (s->text) { av_log(ctx, AV_LOG_ERROR, "Both text and text file provided. Please provide only one\n"); return AVERROR(EINVAL); } if ((err = ff_load_textfile(ctx, (const char *)s->textfile, &s->text, NULL)) < 0) return err; } if (s->reload && !s->textfile) av_log(ctx, AV_LOG_WARNING, "No file to reload\n"); if (s->tc_opt_string) { int ret = av_timecode_init_from_string(&s->tc, s->tc_rate, s->tc_opt_string, ctx); if (ret < 0) return ret; if (s->tc24hmax) s->tc.flags |= AV_TIMECODE_FLAG_24HOURSMAX; if (!s->text) s->text = av_strdup(""); } if (s->text_source_string) { s->text_source = text_source_string_parse(s->text_source_string); if ((int)s->text_source < 0) { av_log(ctx, AV_LOG_ERROR, "Error text source: %s\n", s->text_source_string); return AVERROR(EINVAL); } } if (s->text_source == AV_FRAME_DATA_DETECTION_BBOXES) { if (s->text) { av_log(ctx, AV_LOG_WARNING, "Multiple texts provided, will use text_source only\n"); av_free(s->text); } s->text = av_mallocz(AV_DETECTION_BBOX_LABEL_NAME_MAX_SIZE * (AV_NUM_DETECTION_BBOX_CLASSIFY + 1)); if (!s->text) return AVERROR(ENOMEM); } if (!s->text) { av_log(ctx, AV_LOG_ERROR, "Either text, a valid file, a timecode or text source must be provided\n"); return AVERROR(EINVAL); } s->expand_text = (FFExpandTextContext) { .log_ctx = ctx, .functions = expand_text_functions, .functions_nb = FF_ARRAY_ELEMS(expand_text_functions) }; #if CONFIG_LIBFRIBIDI if (s->text_shaping) if ((err = shape_text(ctx)) < 0) return err; #endif if ((err = FT_Init_FreeType(&(s->library)))) { av_log(ctx, AV_LOG_ERROR, "Could not load FreeType: %s\n", FT_ERRMSG(err)); return AVERROR(EINVAL); } if ((err = load_font(ctx)) < 0) return err; if ((err = update_fontsize(ctx)) < 0) return err; // Always init the stroker, may be needed if borderw is set via command if (FT_Stroker_New(s->library, &s->stroker)) { av_log(ctx, AV_LOG_ERROR, "Could not init FT stroker\n"); return AVERROR_EXTERNAL; } if (s->borderw) { FT_Stroker_Set(s->stroker, s->borderw << 6, FT_STROKER_LINECAP_ROUND, FT_STROKER_LINEJOIN_ROUND, 0); } /* load the fallback glyph with code 0 */ load_glyph(ctx, NULL, 0, 0, 0); if (s->exp_mode == EXP_STRFTIME && (strchr(s->text, '%') || strchr(s->text, '\\'))) av_log(ctx, AV_LOG_WARNING, "expansion=strftime is deprecated.\n"); av_bprint_init(&s->expanded_text, 0, AV_BPRINT_SIZE_UNLIMITED); av_bprint_init(&s->expanded_fontcolor, 0, AV_BPRINT_SIZE_UNLIMITED); return 0; } static int query_formats(AVFilterContext *ctx) { return ff_set_common_formats(ctx, ff_draw_supported_pixel_formats(0)); } static int glyph_enu_border_free(void *opaque, void *elem) { Glyph *glyph = elem; if (glyph->border_glyph != NULL) { for (int t = 0; t < 16; ++t) { if (glyph->border_bglyph[t] != NULL) { FT_Done_Glyph((FT_Glyph)glyph->border_bglyph[t]); glyph->border_bglyph[t] = NULL; } } FT_Done_Glyph(glyph->border_glyph); glyph->border_glyph = NULL; } return 0; } static int glyph_enu_free(void *opaque, void *elem) { Glyph *glyph = elem; FT_Done_Glyph(glyph->glyph); FT_Done_Glyph(glyph->border_glyph); for (int t = 0; t < 16; ++t) { if (glyph->bglyph[t] != NULL) { FT_Done_Glyph((FT_Glyph)glyph->bglyph[t]); } if (glyph->border_bglyph[t] != NULL) { FT_Done_Glyph((FT_Glyph)glyph->border_bglyph[t]); } } av_free(elem); return 0; } static av_cold void uninit(AVFilterContext *ctx) { DrawTextContext *s = ctx->priv; av_expr_free(s->x_pexpr); av_expr_free(s->y_pexpr); av_expr_free(s->a_pexpr); av_expr_free(s->fontsize_pexpr); s->x_pexpr = s->y_pexpr = s->a_pexpr = s->fontsize_pexpr = NULL; av_tree_enumerate(s->glyphs, NULL, NULL, glyph_enu_free); av_tree_destroy(s->glyphs); s->glyphs = NULL; FT_Done_Face(s->face); FT_Stroker_Done(s->stroker); FT_Done_FreeType(s->library); av_bprint_finalize(&s->expanded_text, NULL); av_bprint_finalize(&s->expanded_fontcolor, NULL); } static int config_input(AVFilterLink *inlink) { AVFilterContext *ctx = inlink->dst; DrawTextContext *s = ctx->priv; char *expr; int ret; ff_draw_init2(&s->dc, inlink->format, inlink->colorspace, inlink->color_range, FF_DRAW_PROCESS_ALPHA); ff_draw_color(&s->dc, &s->fontcolor, s->fontcolor.rgba); ff_draw_color(&s->dc, &s->shadowcolor, s->shadowcolor.rgba); ff_draw_color(&s->dc, &s->bordercolor, s->bordercolor.rgba); ff_draw_color(&s->dc, &s->boxcolor, s->boxcolor.rgba); s->var_values[VAR_w] = s->var_values[VAR_W] = s->var_values[VAR_MAIN_W] = inlink->w; s->var_values[VAR_h] = s->var_values[VAR_H] = s->var_values[VAR_MAIN_H] = inlink->h; s->var_values[VAR_SAR] = inlink->sample_aspect_ratio.num ? av_q2d(inlink->sample_aspect_ratio) : 1; s->var_values[VAR_DAR] = (double)inlink->w / inlink->h * s->var_values[VAR_SAR]; s->var_values[VAR_HSUB] = 1 << s->dc.hsub_max; s->var_values[VAR_VSUB] = 1 << s->dc.vsub_max; s->var_values[VAR_X] = NAN; s->var_values[VAR_Y] = NAN; s->var_values[VAR_T] = NAN; av_lfg_init(&s->prng, av_get_random_seed()); av_expr_free(s->x_pexpr); av_expr_free(s->y_pexpr); av_expr_free(s->a_pexpr); s->x_pexpr = s->y_pexpr = s->a_pexpr = NULL; if ((ret = av_expr_parse(&s->x_pexpr, expr = s->x_expr, var_names, NULL, NULL, fun2_names, fun2, 0, ctx)) < 0 || (ret = av_expr_parse(&s->y_pexpr, expr = s->y_expr, var_names, NULL, NULL, fun2_names, fun2, 0, ctx)) < 0 || (ret = av_expr_parse(&s->a_pexpr, expr = s->a_expr, var_names, NULL, NULL, fun2_names, fun2, 0, ctx)) < 0) { av_log(ctx, AV_LOG_ERROR, "Failed to parse expression: %s \n", expr); return AVERROR(EINVAL); } return 0; } static int command(AVFilterContext *ctx, const char *cmd, const char *arg, char *res, int res_len, int flags) { DrawTextContext *old = ctx->priv; DrawTextContext *new = NULL; int ret; if (!strcmp(cmd, "reinit")) { new = av_mallocz(sizeof(DrawTextContext)); if (!new) return AVERROR(ENOMEM); new->class = &drawtext_class; ret = av_opt_copy(new, old); if (ret < 0) goto fail; ctx->priv = new; ret = av_set_options_string(ctx, arg, "=", ":"); if (ret < 0) { ctx->priv = old; goto fail; } ret = init(ctx); if (ret < 0) { uninit(ctx); ctx->priv = old; goto fail; } new->reinit = 1; ctx->priv = old; uninit(ctx); av_freep(&old); ctx->priv = new; return config_input(ctx->inputs[0]); } else { int old_borderw = old->borderw; if ((ret = ff_filter_process_command(ctx, cmd, arg, res, res_len, flags)) < 0) { return ret; } if (old->borderw != old_borderw) { FT_Stroker_Set(old->stroker, old->borderw << 6, FT_STROKER_LINECAP_ROUND, FT_STROKER_LINEJOIN_ROUND, 0); // Dispose the old border glyphs av_tree_enumerate(old->glyphs, NULL, NULL, glyph_enu_border_free); } else if (strcmp(cmd, "fontsize") == 0) { av_expr_free(old->fontsize_pexpr); old->fontsize_pexpr = NULL; old->blank_advance64 = 0; } return config_input(ctx->inputs[0]); } fail: av_log(ctx, AV_LOG_ERROR, "Failed to process command. Continuing with existing parameters.\n"); av_freep(&new); return ret; } static void update_color_with_alpha(DrawTextContext *s, FFDrawColor *color, const FFDrawColor incolor) { *color = incolor; color->rgba[3] = (color->rgba[3] * s->alpha) / 255; ff_draw_color(&s->dc, color, color->rgba); } static void update_alpha(DrawTextContext *s) { double alpha = av_expr_eval(s->a_pexpr, s->var_values, &s->prng); if (isnan(alpha)) return; if (alpha >= 1.0) s->alpha = 255; else if (alpha <= 0) s->alpha = 0; else s->alpha = 256 * alpha; } static int draw_glyphs(DrawTextContext *s, AVFrame *frame, FFDrawColor *color, TextMetrics *metrics, int x, int y, int borderw) { int g, l, x1, y1, w1, h1, idx; int dx = 0, dy = 0, pdx = 0; GlyphInfo *info; Glyph dummy = { 0 }, *glyph; FT_Bitmap bitmap; FT_BitmapGlyph b_glyph; uint8_t j_left = 0, j_right = 0, j_top = 0, j_bottom = 0; int line_w, offset_y = 0; int clip_x = 0, clip_y = 0; j_left = !!(s->text_align & TA_LEFT); j_right = !!(s->text_align & TA_RIGHT); j_top = !!(s->text_align & TA_TOP); j_bottom = !!(s->text_align & TA_BOTTOM); if (j_top && j_bottom) { offset_y = (s->box_height - metrics->height) / 2; } else if (j_bottom) { offset_y = s->box_height - metrics->height; } if ((!j_left || j_right) && !s->tab_warning_printed && s->tab_count > 0) { s->tab_warning_printed = 1; av_log(s, AV_LOG_WARNING, "Tab characters are only supported with left horizontal alignment\n"); } clip_x = FFMIN(metrics->rect_x + s->box_width + s->bb_right, frame->width); clip_y = FFMIN(metrics->rect_y + s->box_height + s->bb_bottom, frame->height); for (l = 0; l < s->line_count; ++l) { TextLine *line = &s->lines[l]; line_w = POS_CEIL(line->width64, 64); for (g = 0; g < line->hb_data.glyph_count; ++g) { info = &line->glyphs[g]; dummy.fontsize = s->fontsize; dummy.code = info->code; glyph = av_tree_find(s->glyphs, &dummy, glyph_cmp, NULL); if (!glyph) { return AVERROR(EINVAL); } idx = get_subpixel_idx(info->shift_x64, info->shift_y64); b_glyph = borderw ? glyph->border_bglyph[idx] : glyph->bglyph[idx]; bitmap = b_glyph->bitmap; x1 = x + info->x + b_glyph->left; y1 = y + info->y - b_glyph->top + offset_y; w1 = bitmap.width; h1 = bitmap.rows; if (j_left && j_right) { x1 += (s->box_width - line_w) / 2; } else if (j_right) { x1 += s->box_width - line_w; } // Offset of the glyph's bitmap in the visible region dx = dy = 0; if (x1 < metrics->rect_x - s->bb_left) { dx = metrics->rect_x - s->bb_left - x1; x1 = metrics->rect_x - s->bb_left; } if (y1 < metrics->rect_y - s->bb_top) { dy = metrics->rect_y - s->bb_top - y1; y1 = metrics->rect_y - s->bb_top; } // check if the glyph is empty or out of the clipping region if (dx >= w1 || dy >= h1 || x1 >= clip_x || y1 >= clip_y) { continue; } pdx = dx + dy * bitmap.pitch; w1 = FFMIN(clip_x - x1, w1 - dx); h1 = FFMIN(clip_y - y1, h1 - dy); ff_blend_mask(&s->dc, color, frame->data, frame->linesize, clip_x, clip_y, bitmap.buffer + pdx, bitmap.pitch, w1, h1, 3, 0, x1, y1); } } return 0; } // Shapes a line of text using libharfbuzz static int shape_text_hb(DrawTextContext *s, HarfbuzzData* hb, const char* text, int textLen) { hb->buf = hb_buffer_create(); if(!hb_buffer_allocation_successful(hb->buf)) { return AVERROR(ENOMEM); } hb_buffer_set_direction(hb->buf, HB_DIRECTION_LTR); hb_buffer_set_script(hb->buf, HB_SCRIPT_LATIN); hb_buffer_set_language(hb->buf, hb_language_from_string("en", -1)); hb_buffer_guess_segment_properties(hb->buf); hb->font = hb_ft_font_create(s->face, NULL); if(hb->font == NULL) { return AVERROR(ENOMEM); } hb_ft_font_set_funcs(hb->font); hb_buffer_add_utf8(hb->buf, text, textLen, 0, -1); hb_shape(hb->font, hb->buf, NULL, 0); hb->glyph_info = hb_buffer_get_glyph_infos(hb->buf, &hb->glyph_count); hb->glyph_pos = hb_buffer_get_glyph_positions(hb->buf, &hb->glyph_count); return 0; } static void hb_destroy(HarfbuzzData *hb) { hb_buffer_destroy(hb->buf); hb_font_destroy(hb->font); hb->buf = NULL; hb->font = NULL; hb->glyph_info = NULL; hb->glyph_pos = NULL; } static int measure_text(AVFilterContext *ctx, TextMetrics *metrics) { DrawTextContext *s = ctx->priv; char *text = s->expanded_text.str; char *textdup = NULL, *start = NULL; int num_chars = 0; int width64 = 0, w64 = 0; int cur_min_y64 = 0, first_max_y64 = -32000; int first_min_x64 = 32000, last_max_x64 = -32000; int min_y64 = 32000, max_y64 = -32000, min_x64 = 32000, max_x64 = -32000; int line_count = 0; uint32_t code = 0; Glyph *glyph = NULL; int i, tab_idx = 0, last_tab_idx = 0, line_offset = 0; char* p; int ret = 0; // Count the lines and the tab characters s->tab_count = 0; for (i = 0, p = text; 1; i++) { GET_UTF8(code, *p ? *p++ : 0, code = 0xfffd; goto continue_on_failed;); continue_on_failed: if (ff_is_newline(code) || code == 0) { ++line_count; if (code == 0) { break; } } else if (code == '\t') { ++s->tab_count; } } // Evaluate the width of the space character if needed to replace tabs if (s->tab_count > 0 && !s->blank_advance64) { HarfbuzzData hb_data; ret = shape_text_hb(s, &hb_data, " ", 1); if(ret != 0) { goto done; } s->blank_advance64 = hb_data.glyph_pos[0].x_advance; hb_destroy(&hb_data); } s->line_count = line_count; s->lines = av_mallocz(line_count * sizeof(TextLine)); s->tab_clusters = av_mallocz(s->tab_count * sizeof(uint32_t)); for (i = 0; i < s->tab_count; ++i) { s->tab_clusters[i] = -1; } start = textdup = av_strdup(text); if (textdup == NULL) { ret = AVERROR(ENOMEM); goto done; } line_count = 0; for (i = 0, p = textdup; 1; i++) { if (*p == '\t') { s->tab_clusters[tab_idx++] = i; *p = ' '; } GET_UTF8(code, *p ? *p++ : 0, code = 0xfffd; goto continue_on_failed2;); continue_on_failed2: if (ff_is_newline(code) || code == 0) { TextLine *cur_line = &s->lines[line_count]; HarfbuzzData *hb = &cur_line->hb_data; cur_line->cluster_offset = line_offset; ret = shape_text_hb(s, hb, start, num_chars); if (ret != 0) { goto done; } w64 = 0; cur_min_y64 = 32000; for (int t = 0; t < hb->glyph_count; ++t) { uint8_t is_tab = last_tab_idx < s->tab_count && hb->glyph_info[t].cluster == s->tab_clusters[last_tab_idx] - line_offset; if (is_tab) { ++last_tab_idx; } ret = load_glyph(ctx, &glyph, hb->glyph_info[t].codepoint, -1, -1); if (ret != 0) { goto done; } if (line_count == 0) { first_max_y64 = FFMAX(glyph->bbox.yMax, first_max_y64); } if (t == 0) { cur_line->offset_left64 = glyph->bbox.xMin; first_min_x64 = FFMIN(glyph->bbox.xMin, first_min_x64); } if (t == hb->glyph_count - 1) { // The following code measures the width of the line up to the last // character's horizontal advance int last_char_width = hb->glyph_pos[t].x_advance; // The following code measures the width of the line up to the rightmost // visible pixel of the last character // int last_char_width = glyph->bbox.xMax; w64 += last_char_width; last_max_x64 = FFMAX(last_char_width, last_max_x64); cur_line->offset_right64 = last_char_width; } else { if (is_tab) { int size = s->blank_advance64 * s->tabsize; w64 = (w64 / size + 1) * size; } else { w64 += hb->glyph_pos[t].x_advance; } } cur_min_y64 = FFMIN(glyph->bbox.yMin, cur_min_y64); min_y64 = FFMIN(glyph->bbox.yMin, min_y64); max_y64 = FFMAX(glyph->bbox.yMax, max_y64); min_x64 = FFMIN(glyph->bbox.xMin, min_x64); max_x64 = FFMAX(glyph->bbox.xMax, max_x64); } cur_line->width64 = w64; av_log(s, AV_LOG_DEBUG, " Line: %d -- glyphs count: %d - width64: %d - offset_left64: %d - offset_right64: %d)\n", line_count, hb->glyph_count, cur_line->width64, cur_line->offset_left64, cur_line->offset_right64); if (w64 > width64) { width64 = w64; } num_chars = -1; start = p; ++line_count; line_offset = i + 1; } if (code == 0) break; ++num_chars; } metrics->line_height64 = s->face->size->metrics.height; metrics->width = POS_CEIL(width64, 64); if (s->y_align == YA_FONT) { metrics->height = POS_CEIL(metrics->line_height64 * line_count, 64); } else { int height64 = (metrics->line_height64 + s->line_spacing * 64) * (FFMAX(0, line_count - 1)) + first_max_y64 - cur_min_y64; metrics->height = POS_CEIL(height64, 64); } metrics->offset_top64 = first_max_y64; metrics->offset_right64 = last_max_x64; metrics->offset_bottom64 = cur_min_y64; metrics->offset_left64 = first_min_x64; metrics->min_x64 = min_x64; metrics->min_y64 = min_y64; metrics->max_x64 = max_x64; metrics->max_y64 = max_y64; done: av_free(textdup); return ret; } static int draw_text(AVFilterContext *ctx, AVFrame *frame) { DrawTextContext *s = ctx->priv; AVFilterLink *inlink = ctx->inputs[0]; int x = 0, y = 0, ret; int shift_x64, shift_y64; int x64, y64; Glyph *glyph = NULL; time_t now = time(0); struct tm ltime; AVBPrint *bp = &s->expanded_text; FFDrawColor fontcolor; FFDrawColor shadowcolor; FFDrawColor bordercolor; FFDrawColor boxcolor; int width = frame->width; int height = frame->height; int rec_x = 0, rec_y = 0, rec_width = 0, rec_height = 0; int is_outside = 0; int last_tab_idx = 0; TextMetrics metrics; av_bprint_clear(bp); if (s->basetime != AV_NOPTS_VALUE) now= frame->pts*av_q2d(ctx->inputs[0]->time_base) + s->basetime/1000000; switch (s->exp_mode) { case EXP_NONE: av_bprintf(bp, "%s", s->text); break; case EXP_NORMAL: if ((ret = ff_expand_text(&s->expand_text, s->text, &s->expanded_text)) < 0) return ret; break; case EXP_STRFTIME: localtime_r(&now, <ime); av_bprint_strftime(bp, s->text, <ime); break; } if (s->tc_opt_string) { char tcbuf[AV_TIMECODE_STR_SIZE]; av_timecode_make_string(&s->tc, tcbuf, inlink->frame_count_out); av_bprint_clear(bp); av_bprintf(bp, "%s%s", s->text, tcbuf); } if (!av_bprint_is_complete(bp)) return AVERROR(ENOMEM); if (s->fontcolor_expr[0]) { /* If expression is set, evaluate and replace the static value */ av_bprint_clear(&s->expanded_fontcolor); if ((ret = ff_expand_text(&s->expand_text, s->fontcolor_expr, &s->expanded_fontcolor)) < 0) return ret; if (!av_bprint_is_complete(&s->expanded_fontcolor)) return AVERROR(ENOMEM); av_log(s, AV_LOG_DEBUG, "Evaluated fontcolor is '%s'\n", s->expanded_fontcolor.str); ret = av_parse_color(s->fontcolor.rgba, s->expanded_fontcolor.str, -1, s); if (ret) return ret; ff_draw_color(&s->dc, &s->fontcolor, s->fontcolor.rgba); } if ((ret = update_fontsize(ctx)) < 0) { return ret; } if ((ret = measure_text(ctx, &metrics)) < 0) { return ret; } s->max_glyph_h = POS_CEIL(metrics.max_y64 - metrics.min_y64, 64); s->max_glyph_w = POS_CEIL(metrics.max_x64 - metrics.min_x64, 64); s->var_values[VAR_TW] = s->var_values[VAR_TEXT_W] = metrics.width; s->var_values[VAR_TH] = s->var_values[VAR_TEXT_H] = metrics.height; s->var_values[VAR_MAX_GLYPH_W] = s->max_glyph_w; s->var_values[VAR_MAX_GLYPH_H] = s->max_glyph_h; s->var_values[VAR_MAX_GLYPH_A] = s->var_values[VAR_ASCENT] = POS_CEIL(metrics.max_y64, 64); s->var_values[VAR_FONT_A] = s->face->size->metrics.ascender / 64; s->var_values[VAR_MAX_GLYPH_D] = s->var_values[VAR_DESCENT] = POS_CEIL(metrics.min_y64, 64); s->var_values[VAR_FONT_D] = -s->face->size->metrics.descender / 64; s->var_values[VAR_TOP_A] = POS_CEIL(metrics.offset_top64, 64); s->var_values[VAR_BOTTOM_D] = -POS_CEIL(metrics.offset_bottom64, 64); s->var_values[VAR_LINE_H] = s->var_values[VAR_LH] = metrics.line_height64 / 64.; if (s->text_source == AV_FRAME_DATA_DETECTION_BBOXES) { s->var_values[VAR_X] = s->x; s->var_values[VAR_Y] = s->y; } else { s->x = s->var_values[VAR_X] = av_expr_eval(s->x_pexpr, s->var_values, &s->prng); s->y = s->var_values[VAR_Y] = av_expr_eval(s->y_pexpr, s->var_values, &s->prng); /* It is necessary if x is expressed from y */ s->x = s->var_values[VAR_X] = av_expr_eval(s->x_pexpr, s->var_values, &s->prng); } update_alpha(s); update_color_with_alpha(s, &fontcolor , s->fontcolor ); update_color_with_alpha(s, &shadowcolor, s->shadowcolor); update_color_with_alpha(s, &bordercolor, s->bordercolor); update_color_with_alpha(s, &boxcolor , s->boxcolor ); if (s->draw_box && s->boxborderw) { int bbsize[4]; int count; count = string_to_array(s->boxborderw, bbsize, 4); if (count == 1) { s->bb_top = s->bb_right = s->bb_bottom = s->bb_left = bbsize[0]; } else if (count == 2) { s->bb_top = s->bb_bottom = bbsize[0]; s->bb_right = s->bb_left = bbsize[1]; } else if (count == 3) { s->bb_top = bbsize[0]; s->bb_right = s->bb_left = bbsize[1]; s->bb_bottom = bbsize[2]; } else if (count == 4) { s->bb_top = bbsize[0]; s->bb_right = bbsize[1]; s->bb_bottom = bbsize[2]; s->bb_left = bbsize[3]; } } else { s->bb_top = s->bb_right = s->bb_bottom = s->bb_left = 0; } if (s->fix_bounds) { /* calculate footprint of text effects */ int borderoffset = s->borderw ? FFMAX(s->borderw, 0) : 0; int offsetleft = FFMAX3(FFMAX(s->bb_left, 0), borderoffset, (s->shadowx < 0 ? FFABS(s->shadowx) : 0)); int offsettop = FFMAX3(FFMAX(s->bb_top, 0), borderoffset, (s->shadowy < 0 ? FFABS(s->shadowy) : 0)); int offsetright = FFMAX3(FFMAX(s->bb_right, 0), borderoffset, (s->shadowx > 0 ? s->shadowx : 0)); int offsetbottom = FFMAX3(FFMAX(s->bb_bottom, 0), borderoffset, (s->shadowy > 0 ? s->shadowy : 0)); if (s->x - offsetleft < 0) s->x = offsetleft; if (s->y - offsettop < 0) s->y = offsettop; if (s->x + metrics.width + offsetright > width) s->x = FFMAX(width - metrics.width - offsetright, 0); if (s->y + metrics.height + offsetbottom > height) s->y = FFMAX(height - metrics.height - offsetbottom, 0); } x = 0; y = 0; x64 = (int)(s->x * 64.); if (s->y_align == YA_FONT) { y64 = (int)(s->y * 64. + s->face->size->metrics.ascender); } else if (s->y_align == YA_BASELINE) { y64 = (int)(s->y * 64.); } else { y64 = (int)(s->y * 64. + metrics.offset_top64); } for (int l = 0; l < s->line_count; ++l) { TextLine *line = &s->lines[l]; HarfbuzzData *hb = &line->hb_data; line->glyphs = av_mallocz(hb->glyph_count * sizeof(GlyphInfo)); for (int t = 0; t < hb->glyph_count; ++t) { GlyphInfo *g_info = &line->glyphs[t]; uint8_t is_tab = last_tab_idx < s->tab_count && hb->glyph_info[t].cluster == s->tab_clusters[last_tab_idx] - line->cluster_offset; int true_x, true_y; if (is_tab) { ++last_tab_idx; } true_x = x + hb->glyph_pos[t].x_offset; true_y = y + hb->glyph_pos[t].y_offset; shift_x64 = (((x64 + true_x) >> 4) & 0b0011) << 4; shift_y64 = ((4 - (((y64 + true_y) >> 4) & 0b0011)) & 0b0011) << 4; ret = load_glyph(ctx, &glyph, hb->glyph_info[t].codepoint, shift_x64, shift_y64); if (ret != 0) { return ret; } g_info->code = hb->glyph_info[t].codepoint; g_info->x = (x64 + true_x) >> 6; g_info->y = ((y64 + true_y) >> 6) + (shift_y64 > 0 ? 1 : 0); g_info->shift_x64 = shift_x64; g_info->shift_y64 = shift_y64; if (!is_tab) { x += hb->glyph_pos[t].x_advance; } else { int size = s->blank_advance64 * s->tabsize; x = (x / size + 1) * size; } y += hb->glyph_pos[t].y_advance; } y += metrics.line_height64 + s->line_spacing * 64; x = 0; } metrics.rect_x = s->x; if (s->y_align == YA_BASELINE) { metrics.rect_y = s->y - metrics.offset_top64 / 64; } else { metrics.rect_y = s->y; } s->box_width = s->boxw == 0 ? metrics.width : s->boxw; s->box_height = s->boxh == 0 ? metrics.height : s->boxh; if (!s->draw_box) { // Create a border for the clipping region to take into account subpixel // errors in text measurement and effects. int borderoffset = s->borderw ? FFMAX(s->borderw, 0) : 0; s->bb_left = borderoffset + (s->shadowx < 0 ? FFABS(s->shadowx) : 0) + 1; s->bb_top = borderoffset + (s->shadowy < 0 ? FFABS(s->shadowy) : 0) + 1; s->bb_right = borderoffset + (s->shadowx > 0 ? s->shadowx : 0) + 1; s->bb_bottom = borderoffset + (s->shadowy > 0 ? s->shadowy : 0) + 1; } /* Check if the whole box is out of the frame */ is_outside = metrics.rect_x - s->bb_left >= width || metrics.rect_y - s->bb_top >= height || metrics.rect_x + s->box_width + s->bb_right <= 0 || metrics.rect_y + s->box_height + s->bb_bottom <= 0; if (!is_outside) { /* draw box */ if (s->draw_box) { rec_x = metrics.rect_x - s->bb_left; rec_y = metrics.rect_y - s->bb_top; rec_width = s->box_width + s->bb_right + s->bb_left; rec_height = s->box_height + s->bb_bottom + s->bb_top; ff_blend_rectangle(&s->dc, &boxcolor, frame->data, frame->linesize, width, height, rec_x, rec_y, rec_width, rec_height); } if (s->shadowx || s->shadowy) { if ((ret = draw_glyphs(s, frame, &shadowcolor, &metrics, s->shadowx, s->shadowy, s->borderw)) < 0) { return ret; } } if (s->borderw) { if ((ret = draw_glyphs(s, frame, &bordercolor, &metrics, 0, 0, s->borderw)) < 0) { return ret; } } if ((ret = draw_glyphs(s, frame, &fontcolor, &metrics, 0, 0, 0)) < 0) { return ret; } } // FREE data structures for (int l = 0; l < s->line_count; ++l) { TextLine *line = &s->lines[l]; av_freep(&line->glyphs); hb_destroy(&line->hb_data); } av_freep(&s->lines); av_freep(&s->tab_clusters); return 0; } static int filter_frame(AVFilterLink *inlink, AVFrame *frame) { AVFilterContext *ctx = inlink->dst; AVFilterLink *outlink = ctx->outputs[0]; DrawTextContext *s = ctx->priv; int ret; const AVDetectionBBoxHeader *header = NULL; const AVDetectionBBox *bbox; AVFrameSideData *sd; int loop = 1; if (s->text_source == AV_FRAME_DATA_DETECTION_BBOXES) { sd = av_frame_get_side_data(frame, AV_FRAME_DATA_DETECTION_BBOXES); if (sd) { header = (AVDetectionBBoxHeader *)sd->data; loop = header->nb_bboxes; } else { av_log(s, AV_LOG_WARNING, "No detection bboxes.\n"); return ff_filter_frame(outlink, frame); } } if (s->reload && !(inlink->frame_count_out % s->reload)) { if ((ret = ff_load_textfile(ctx, (const char *)s->textfile, &s->text, NULL)) < 0) { av_frame_free(&frame); return ret; } #if CONFIG_LIBFRIBIDI if (s->text_shaping) if ((ret = shape_text(ctx)) < 0) { av_frame_free(&frame); return ret; } #endif } s->var_values[VAR_N] = inlink->frame_count_out + s->start_number; s->var_values[VAR_T] = frame->pts == AV_NOPTS_VALUE ? NAN : frame->pts * av_q2d(inlink->time_base); s->var_values[VAR_PICT_TYPE] = frame->pict_type; #if FF_API_FRAME_PKT FF_DISABLE_DEPRECATION_WARNINGS s->var_values[VAR_PKT_POS] = frame->pkt_pos; s->var_values[VAR_PKT_SIZE] = frame->pkt_size; FF_ENABLE_DEPRECATION_WARNINGS #endif s->var_values[VAR_DURATION] = frame->duration * av_q2d(inlink->time_base); s->metadata = frame->metadata; for (int i = 0; i < loop; i++) { if (header) { bbox = av_get_detection_bbox(header, i); strcpy(s->text, bbox->detect_label); for (int j = 0; j < bbox->classify_count; j++) { strcat(s->text, ", "); strcat(s->text, bbox->classify_labels[j]); } s->x = bbox->x; s->y = bbox->y - s->fontsize; } draw_text(ctx, frame); } return ff_filter_frame(outlink, frame); } static const AVFilterPad avfilter_vf_drawtext_inputs[] = { { .name = "default", .type = AVMEDIA_TYPE_VIDEO, .flags = AVFILTERPAD_FLAG_NEEDS_WRITABLE, .filter_frame = filter_frame, .config_props = config_input, }, }; const AVFilter ff_vf_drawtext = { .name = "drawtext", .description = NULL_IF_CONFIG_SMALL("Draw text on top of video frames using libfreetype library."), .priv_size = sizeof(DrawTextContext), .priv_class = &drawtext_class, .init = init, .uninit = uninit, FILTER_INPUTS(avfilter_vf_drawtext_inputs), FILTER_OUTPUTS(ff_video_default_filterpad), FILTER_QUERY_FUNC(query_formats), .process_command = command, .flags = AVFILTER_FLAG_SUPPORT_TIMELINE_GENERIC, };