/*
* Copyright (c) 2023 Francesco Carusi
* Copyright (c) 2011 Stefano Sabatini
* Copyright (c) 2010 S.N. Hemanth Meenakshisundaram
* Copyright (c) 2003 Gustavo Sverzut Barbieri <gsbarbieri@yahoo.com.br>
*
* 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 <sys/time.h>
#endif
#include <sys/types.h>
#include <sys/stat.h>
#include <time.h>
#if HAVE_UNISTD_H
#include <unistd.h>
#endif
#include <fenv.h>
#if CONFIG_LIBFONTCONFIG
#include <fontconfig/fontconfig.h>
#endif
#include "libavutil/avstring.h"
#include "libavutil/bprint.h"
#include "libavutil/common.h"
#include "libavutil/eval.h"
#include "libavutil/mem.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 <fribidi.h>
#endif
#include <ft2build.h>
#include FT_FREETYPE_H
#include FT_GLYPH_H
#include FT_STROKER_H
#include <hb.h>
#include <hb-ft.h>
// 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,
};