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FFmpeg/libavfilter/vf_drawtext.c
Paul B Mahol c5a1b18f18 lavfi/drawtext: add support for printing frame metadata
Signed-off-by: Paul B Mahol <onemda@gmail.com>
2013-07-09 15:21:01 +00:00

1046 lines
36 KiB
C

/*
* 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 <sys/time.h>
#include <time.h>
#include "config.h"
#include "libavutil/avstring.h"
#include "libavutil/bprint.h"
#include "libavutil/common.h"
#include "libavutil/file.h"
#include "libavutil/eval.h"
#include "libavutil/opt.h"
#include "libavutil/random_seed.h"
#include "libavutil/parseutils.h"
#include "libavutil/timecode.h"
#include "libavutil/tree.h"
#include "libavutil/lfg.h"
#include "avfilter.h"
#include "drawutils.h"
#include "formats.h"
#include "internal.h"
#include "video.h"
#include <ft2build.h>
#include <freetype/config/ftheader.h>
#include FT_FREETYPE_H
#include FT_GLYPH_H
#if CONFIG_FONTCONFIG
#include <fontconfig/fontconfig.h>
#endif
static const char *const var_names[] = {
"dar",
"hsub", "vsub",
"line_h", "lh", ///< line height, same as max_glyph_h
"main_h", "h", "H", ///< height of the input video
"main_w", "w", "W", ///< width of the input video
"max_glyph_a", "ascent", ///< max glyph ascent
"max_glyph_d", "descent", ///< min glyph descent
"max_glyph_h", ///< max glyph height
"max_glyph_w", ///< max glyph width
"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",
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_N,
VAR_SAR,
VAR_T,
VAR_TEXT_H, VAR_TH,
VAR_TEXT_W, VAR_TW,
VAR_X,
VAR_Y,
VAR_PICT_TYPE,
VAR_VARS_NB
};
enum expansion_mode {
EXP_NONE,
EXP_NORMAL,
EXP_STRFTIME,
};
typedef struct {
const AVClass *class;
enum expansion_mode exp_mode; ///< expansion mode to use for the text
int reinit; ///< tells if the filter is being reinited
uint8_t *fontfile; ///< font to be used
uint8_t *text; ///< text to be drawn
AVBPrint expanded_text; ///< used to contain the expanded text
int ft_load_flags; ///< flags used for loading fonts, see FT_LOAD_*
FT_Vector *positions; ///< positions for each element in the text
size_t nb_positions; ///< number of elements of positions array
char *textfile; ///< file with text to be drawn
int x; ///< x position to start drawing text
int y; ///< y position to start drawing text
int max_glyph_w; ///< max glyph width
int max_glyph_h; ///< max glyph height
int shadowx, shadowy;
unsigned int fontsize; ///< font size to use
short int draw_box; ///< draw box around text - true or false
int use_kerning; ///< font kerning is used - true/false
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 boxcolor; ///< background color
FT_Library library; ///< freetype font library handle
FT_Face face; ///< freetype font face 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 *draw_expr; ///< expression for draw
AVExpr *draw_pexpr; ///< parsed expression for draw
int draw; ///< set to zero to prevent drawing
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 for each frame
int start_number; ///< starting frame number for n/frame_num var
AVDictionary *metadata;
} DrawTextContext;
#define OFFSET(x) offsetof(DrawTextContext, x)
#define FLAGS AV_OPT_FLAG_FILTERING_PARAM|AV_OPT_FLAG_VIDEO_PARAM
static const AVOption drawtext_options[]= {
{"fontfile", "set font file", OFFSET(fontfile), AV_OPT_TYPE_STRING, {.str=NULL}, CHAR_MIN, CHAR_MAX, FLAGS},
{"text", "set text", OFFSET(text), AV_OPT_TYPE_STRING, {.str=NULL}, CHAR_MIN, CHAR_MAX, FLAGS},
{"textfile", "set text file", OFFSET(textfile), AV_OPT_TYPE_STRING, {.str=NULL}, CHAR_MIN, CHAR_MAX, FLAGS},
{"fontcolor", "set foreground color", OFFSET(fontcolor.rgba), AV_OPT_TYPE_COLOR, {.str="black"}, CHAR_MIN, CHAR_MAX, FLAGS},
{"boxcolor", "set box color", OFFSET(boxcolor.rgba), AV_OPT_TYPE_COLOR, {.str="white"}, CHAR_MIN, CHAR_MAX, FLAGS},
{"shadowcolor", "set shadow color", OFFSET(shadowcolor.rgba), AV_OPT_TYPE_COLOR, {.str="black"}, CHAR_MIN, CHAR_MAX, FLAGS},
{"box", "set box", OFFSET(draw_box), AV_OPT_TYPE_INT, {.i64=0}, 0, 1 , FLAGS},
{"fontsize", "set font size", OFFSET(fontsize), AV_OPT_TYPE_INT, {.i64=0}, 0, INT_MAX , FLAGS},
{"x", "set x expression", OFFSET(x_expr), AV_OPT_TYPE_STRING, {.str="0"}, CHAR_MIN, CHAR_MAX, FLAGS},
{"y", "set y expression", OFFSET(y_expr), AV_OPT_TYPE_STRING, {.str="0"}, CHAR_MIN, CHAR_MAX, FLAGS},
{"shadowx", "set x", OFFSET(shadowx), AV_OPT_TYPE_INT, {.i64=0}, INT_MIN, INT_MAX , FLAGS},
{"shadowy", "set y", OFFSET(shadowy), AV_OPT_TYPE_INT, {.i64=0}, INT_MIN, INT_MAX , FLAGS},
{"tabsize", "set tab size", OFFSET(tabsize), AV_OPT_TYPE_INT, {.i64=4}, 0, INT_MAX , FLAGS},
{"basetime", "set base time", OFFSET(basetime), AV_OPT_TYPE_INT64, {.i64=AV_NOPTS_VALUE}, INT64_MIN, INT64_MAX , FLAGS},
{"draw", "if false do not draw", OFFSET(draw_expr), AV_OPT_TYPE_STRING, {.str="1"}, CHAR_MIN, CHAR_MAX, FLAGS},
{"expansion", "set the expansion mode", OFFSET(exp_mode), AV_OPT_TYPE_INT, {.i64=EXP_NORMAL}, 0, 2, FLAGS, "expansion"},
{"none", "set no expansion", OFFSET(exp_mode), AV_OPT_TYPE_CONST, {.i64=EXP_NONE}, 0, 0, FLAGS, "expansion"},
{"normal", "set normal expansion", OFFSET(exp_mode), AV_OPT_TYPE_CONST, {.i64=EXP_NORMAL}, 0, 0, FLAGS, "expansion"},
{"strftime", "set strftime expansion (deprecated)", OFFSET(exp_mode), AV_OPT_TYPE_CONST, {.i64=EXP_STRFTIME}, 0, 0, FLAGS, "expansion"},
{"timecode", "set initial timecode", OFFSET(tc_opt_string), AV_OPT_TYPE_STRING, {.str=NULL}, CHAR_MIN, CHAR_MAX, FLAGS},
{"tc24hmax", "set 24 hours max (timecode only)", OFFSET(tc24hmax), AV_OPT_TYPE_INT, {.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 for each frame", OFFSET(reload), AV_OPT_TYPE_INT, {.i64=0}, 0, 1, FLAGS},
{"fix_bounds", "if true, check and fix text coords to avoid clipping", OFFSET(fix_bounds), AV_OPT_TYPE_INT, {.i64=1}, 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},
/* FT_LOAD_* flags */
{ "ft_load_flags", "set font loading flags for libfreetype", OFFSET(ft_load_flags), AV_OPT_TYPE_FLAGS, { .i64 = FT_LOAD_DEFAULT | FT_LOAD_RENDER}, 0, INT_MAX, FLAGS, "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 } };
struct ft_error
{
int err;
const char *err_msg;
} static ft_errors[] =
#include FT_ERRORS_H
#define FT_ERRMSG(e) ft_errors[e].err_msg
typedef struct {
FT_Glyph *glyph;
uint32_t code;
FT_Bitmap bitmap; ///< array holding bitmaps of font
FT_BBox bbox;
int advance;
int bitmap_left;
int bitmap_top;
} Glyph;
static int glyph_cmp(void *key, const void *b)
{
const Glyph *a = key, *bb = b;
int64_t diff = (int64_t)a->code - (int64_t)bb->code;
return diff > 0 ? 1 : diff < 0 ? -1 : 0;
}
/**
* Load glyphs corresponding to the UTF-32 codepoint code.
*/
static int load_glyph(AVFilterContext *ctx, Glyph **glyph_ptr, uint32_t code)
{
DrawTextContext *s = ctx->priv;
Glyph *glyph;
struct AVTreeNode *node = NULL;
int ret;
/* load glyph into s->face->glyph */
if (FT_Load_Char(s->face, code, s->ft_load_flags))
return AVERROR(EINVAL);
/* save glyph */
if (!(glyph = av_mallocz(sizeof(*glyph))) ||
!(glyph->glyph = av_mallocz(sizeof(*glyph->glyph)))) {
ret = AVERROR(ENOMEM);
goto error;
}
glyph->code = code;
if (FT_Get_Glyph(s->face->glyph, glyph->glyph)) {
ret = AVERROR(EINVAL);
goto error;
}
glyph->bitmap = s->face->glyph->bitmap;
glyph->bitmap_left = s->face->glyph->bitmap_left;
glyph->bitmap_top = s->face->glyph->bitmap_top;
glyph->advance = s->face->glyph->advance.x >> 6;
/* measure text height to calculate text_height (or the maximum text height) */
FT_Glyph_Get_CBox(*glyph->glyph, ft_glyph_bbox_pixels, &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);
if (glyph_ptr)
*glyph_ptr = glyph;
return 0;
error:
if (glyph)
av_freep(&glyph->glyph);
av_freep(&glyph);
av_freep(&node);
return ret;
}
static int load_font_file(AVFilterContext *ctx, const char *path, int index,
const char **error)
{
DrawTextContext *s = ctx->priv;
int err;
err = FT_New_Face(s->library, path, index, &s->face);
if (err) {
*error = FT_ERRMSG(err);
return AVERROR(EINVAL);
}
return 0;
}
#if CONFIG_FONTCONFIG
static int load_font_fontconfig(AVFilterContext *ctx, const char **error)
{
DrawTextContext *s = ctx->priv;
FcConfig *fontconfig;
FcPattern *pattern, *fpat;
FcResult result = FcResultMatch;
FcChar8 *filename;
int err, index;
double size;
fontconfig = FcInitLoadConfigAndFonts();
if (!fontconfig) {
*error = "impossible to init fontconfig\n";
return AVERROR(EINVAL);
}
pattern = FcNameParse(s->fontfile ? s->fontfile :
(uint8_t *)(intptr_t)"default");
if (!pattern) {
*error = "could not parse fontconfig pattern";
return AVERROR(EINVAL);
}
if (!FcConfigSubstitute(fontconfig, pattern, FcMatchPattern)) {
*error = "could not substitue fontconfig options"; /* very unlikely */
return AVERROR(EINVAL);
}
FcDefaultSubstitute(pattern);
fpat = FcFontMatch(fontconfig, pattern, &result);
if (!fpat || result != FcResultMatch) {
*error = "impossible to find a matching font";
return AVERROR(EINVAL);
}
if (FcPatternGetString (fpat, FC_FILE, 0, &filename) != FcResultMatch ||
FcPatternGetInteger(fpat, FC_INDEX, 0, &index ) != FcResultMatch ||
FcPatternGetDouble (fpat, FC_SIZE, 0, &size ) != FcResultMatch) {
*error = "impossible to find font information";
return AVERROR(EINVAL);
}
av_log(ctx, AV_LOG_INFO, "Using \"%s\"\n", filename);
if (!s->fontsize)
s->fontsize = size + 0.5;
err = load_font_file(ctx, filename, index, error);
if (err)
return err;
FcPatternDestroy(fpat);
FcPatternDestroy(pattern);
FcConfigDestroy(fontconfig);
return 0;
}
#endif
static int load_font(AVFilterContext *ctx)
{
DrawTextContext *s = ctx->priv;
int err;
const char *error = "unknown error\n";
/* load the face, and set up the encoding, which is by default UTF-8 */
err = load_font_file(ctx, s->fontfile, 0, &error);
if (!err)
return 0;
#if CONFIG_FONTCONFIG
err = load_font_fontconfig(ctx, &error);
if (!err)
return 0;
#endif
av_log(ctx, AV_LOG_ERROR, "Could not load font \"%s\": %s\n",
s->fontfile, error);
return err;
}
static int load_textfile(AVFilterContext *ctx)
{
DrawTextContext *s = ctx->priv;
int err;
uint8_t *textbuf;
size_t textbuf_size;
if ((err = av_file_map(s->textfile, &textbuf, &textbuf_size, 0, ctx)) < 0) {
av_log(ctx, AV_LOG_ERROR,
"The text file '%s' could not be read or is empty\n",
s->textfile);
return err;
}
if (!(s->text = av_realloc(s->text, textbuf_size + 1)))
return AVERROR(ENOMEM);
memcpy(s->text, textbuf, textbuf_size);
s->text[textbuf_size] = 0;
av_file_unmap(textbuf, textbuf_size);
return 0;
}
static av_cold int init(AVFilterContext *ctx)
{
int err;
DrawTextContext *s = ctx->priv;
Glyph *glyph;
if (!s->fontfile && !CONFIG_FONTCONFIG) {
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 = load_textfile(ctx)) < 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) {
av_log(ctx, AV_LOG_ERROR,
"Either text, a valid file or a timecode must be provided\n");
return AVERROR(EINVAL);
}
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);
}
err = load_font(ctx);
if (err)
return err;
if (!s->fontsize)
s->fontsize = 16;
if ((err = FT_Set_Pixel_Sizes(s->face, 0, s->fontsize))) {
av_log(ctx, AV_LOG_ERROR, "Could not set font size to %d pixels: %s\n",
s->fontsize, FT_ERRMSG(err));
return AVERROR(EINVAL);
}
s->use_kerning = FT_HAS_KERNING(s->face);
/* load the fallback glyph with code 0 */
load_glyph(ctx, NULL, 0);
/* set the tabsize in pixels */
if ((err = load_glyph(ctx, &glyph, ' ')) < 0) {
av_log(ctx, AV_LOG_ERROR, "Could not set tabsize.\n");
return err;
}
s->tabsize *= glyph->advance;
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);
return 0;
}
static int query_formats(AVFilterContext *ctx)
{
ff_set_common_formats(ctx, ff_draw_supported_pixel_formats(0));
return 0;
}
static int glyph_enu_free(void *opaque, void *elem)
{
Glyph *glyph = elem;
FT_Done_Glyph(*glyph->glyph);
av_freep(&glyph->glyph);
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->draw_pexpr);
s->x_pexpr = s->y_pexpr = s->draw_pexpr = NULL;
av_freep(&s->positions);
s->nb_positions = 0;
av_tree_enumerate(s->glyphs, NULL, NULL, glyph_enu_free);
av_tree_destroy(s->glyphs);
s->glyphs = NULL;
FT_Done_Face(s->face);
FT_Done_FreeType(s->library);
av_bprint_finalize(&s->expanded_text, NULL);
}
static inline int is_newline(uint32_t c)
{
return c == '\n' || c == '\r' || c == '\f' || c == '\v';
}
static int config_input(AVFilterLink *inlink)
{
AVFilterContext *ctx = inlink->dst;
DrawTextContext *s = ctx->priv;
int ret;
ff_draw_init(&s->dc, inlink->format, 0);
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->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->draw_pexpr);
s->x_pexpr = s->y_pexpr = s->draw_pexpr = NULL;
if ((ret = av_expr_parse(&s->x_pexpr, s->x_expr, var_names,
NULL, NULL, fun2_names, fun2, 0, ctx)) < 0 ||
(ret = av_expr_parse(&s->y_pexpr, s->y_expr, var_names,
NULL, NULL, fun2_names, fun2, 0, ctx)) < 0 ||
(ret = av_expr_parse(&s->draw_pexpr, s->draw_expr, var_names,
NULL, NULL, fun2_names, fun2, 0, ctx)) < 0)
return AVERROR(EINVAL);
return 0;
}
static int command(AVFilterContext *ctx, const char *cmd, const char *arg, char *res, int res_len, int flags)
{
DrawTextContext *s = ctx->priv;
if (!strcmp(cmd, "reinit")) {
int ret;
uninit(ctx);
s->reinit = 1;
if ((ret = init(ctx)) < 0)
return ret;
return config_input(ctx->inputs[0]);
}
return AVERROR(ENOSYS);
}
static int func_pict_type(AVFilterContext *ctx, AVBPrint *bp,
char *fct, unsigned argc, char **argv, int tag)
{
DrawTextContext *s = ctx->priv;
av_bprintf(bp, "%c", av_get_picture_type_char(s->var_values[VAR_PICT_TYPE]));
return 0;
}
static int func_pts(AVFilterContext *ctx, AVBPrint *bp,
char *fct, unsigned argc, char **argv, int tag)
{
DrawTextContext *s = ctx->priv;
av_bprintf(bp, "%.6f", s->var_values[VAR_T]);
return 0;
}
static int func_frame_num(AVFilterContext *ctx, AVBPrint *bp,
char *fct, unsigned argc, char **argv, int tag)
{
DrawTextContext *s = ctx->priv;
av_bprintf(bp, "%d", (int)s->var_values[VAR_N]);
return 0;
}
static int func_metadata(AVFilterContext *ctx, AVBPrint *bp,
char *fct, unsigned argc, char **argv, int tag)
{
DrawTextContext *s = ctx->priv;
AVDictionaryEntry *e = av_dict_get(s->metadata, argv[0], NULL, 0);
if (e && e->value)
av_bprintf(bp, "%s", e->value);
return 0;
}
#if !HAVE_LOCALTIME_R
static void localtime_r(const time_t *t, struct tm *tm)
{
*tm = *localtime(t);
}
#endif
static int func_strftime(AVFilterContext *ctx, AVBPrint *bp,
char *fct, unsigned argc, char **argv, int tag)
{
const char *fmt = argc ? argv[0] : "%Y-%m-%d %H:%M:%S";
time_t now;
struct tm tm;
time(&now);
if (tag == 'L')
localtime_r(&now, &tm);
else
tm = *gmtime(&now);
av_bprint_strftime(bp, fmt, &tm);
return 0;
}
static int func_eval_expr(AVFilterContext *ctx, AVBPrint *bp,
char *fct, unsigned argc, char **argv, int tag)
{
DrawTextContext *s = ctx->priv;
double res;
int ret;
ret = av_expr_parse_and_eval(&res, argv[0], var_names, s->var_values,
NULL, NULL, fun2_names, fun2,
&s->prng, 0, ctx);
if (ret < 0)
av_log(ctx, AV_LOG_ERROR,
"Expression '%s' for the expr text expansion function is not valid\n",
argv[0]);
else
av_bprintf(bp, "%f", res);
return ret;
}
static const struct drawtext_function {
const char *name;
unsigned argc_min, argc_max;
int tag; /**< opaque argument to func */
int (*func)(AVFilterContext *, AVBPrint *, char *, unsigned, char **, int);
} functions[] = {
{ "expr", 1, 1, 0, func_eval_expr },
{ "e", 1, 1, 0, func_eval_expr },
{ "pict_type", 0, 0, 0, func_pict_type },
{ "pts", 0, 0, 0, func_pts },
{ "gmtime", 0, 1, 'G', func_strftime },
{ "localtime", 0, 1, 'L', func_strftime },
{ "frame_num", 0, 0, 0, func_frame_num },
{ "n", 0, 0, 0, func_frame_num },
{ "metadata", 1, 1, 0, func_metadata },
};
static int eval_function(AVFilterContext *ctx, AVBPrint *bp, char *fct,
unsigned argc, char **argv)
{
unsigned i;
for (i = 0; i < FF_ARRAY_ELEMS(functions); i++) {
if (strcmp(fct, functions[i].name))
continue;
if (argc < functions[i].argc_min) {
av_log(ctx, AV_LOG_ERROR, "%%{%s} requires at least %d arguments\n",
fct, functions[i].argc_min);
return AVERROR(EINVAL);
}
if (argc > functions[i].argc_max) {
av_log(ctx, AV_LOG_ERROR, "%%{%s} requires at most %d arguments\n",
fct, functions[i].argc_max);
return AVERROR(EINVAL);
}
break;
}
if (i >= FF_ARRAY_ELEMS(functions)) {
av_log(ctx, AV_LOG_ERROR, "%%{%s} is not known\n", fct);
return AVERROR(EINVAL);
}
return functions[i].func(ctx, bp, fct, argc, argv, functions[i].tag);
}
static int expand_function(AVFilterContext *ctx, AVBPrint *bp, char **rtext)
{
const char *text = *rtext;
char *argv[16] = { NULL };
unsigned argc = 0, i;
int ret;
if (*text != '{') {
av_log(ctx, AV_LOG_ERROR, "Stray %% near '%s'\n", text);
return AVERROR(EINVAL);
}
text++;
while (1) {
if (!(argv[argc++] = av_get_token(&text, ":}"))) {
ret = AVERROR(ENOMEM);
goto end;
}
if (!*text) {
av_log(ctx, AV_LOG_ERROR, "Unterminated %%{} near '%s'\n", *rtext);
ret = AVERROR(EINVAL);
goto end;
}
if (argc == FF_ARRAY_ELEMS(argv))
av_freep(&argv[--argc]); /* error will be caught later */
if (*text == '}')
break;
text++;
}
if ((ret = eval_function(ctx, bp, argv[0], argc - 1, argv + 1)) < 0)
goto end;
ret = 0;
*rtext = (char *)text + 1;
end:
for (i = 0; i < argc; i++)
av_freep(&argv[i]);
return ret;
}
static int expand_text(AVFilterContext *ctx)
{
DrawTextContext *s = ctx->priv;
char *text = s->text;
AVBPrint *bp = &s->expanded_text;
int ret;
av_bprint_clear(bp);
while (*text) {
if (*text == '\\' && text[1]) {
av_bprint_chars(bp, text[1], 1);
text += 2;
} else if (*text == '%') {
text++;
if ((ret = expand_function(ctx, bp, &text)) < 0)
return ret;
} else {
av_bprint_chars(bp, *text, 1);
text++;
}
}
if (!av_bprint_is_complete(bp))
return AVERROR(ENOMEM);
return 0;
}
static int draw_glyphs(DrawTextContext *s, AVFrame *frame,
int width, int height, const uint8_t rgbcolor[4], FFDrawColor *color, int x, int y)
{
char *text = s->expanded_text.str;
uint32_t code = 0;
int i, x1, y1;
uint8_t *p;
Glyph *glyph = NULL;
for (i = 0, p = text; *p; i++) {
Glyph dummy = { 0 };
GET_UTF8(code, *p++, continue;);
/* skip new line chars, just go to new line */
if (code == '\n' || code == '\r' || code == '\t')
continue;
dummy.code = code;
glyph = av_tree_find(s->glyphs, &dummy, (void *)glyph_cmp, NULL);
if (glyph->bitmap.pixel_mode != FT_PIXEL_MODE_MONO &&
glyph->bitmap.pixel_mode != FT_PIXEL_MODE_GRAY)
return AVERROR(EINVAL);
x1 = s->positions[i].x+s->x+x;
y1 = s->positions[i].y+s->y+y;
ff_blend_mask(&s->dc, color,
frame->data, frame->linesize, width, height,
glyph->bitmap.buffer, glyph->bitmap.pitch,
glyph->bitmap.width, glyph->bitmap.rows,
glyph->bitmap.pixel_mode == FT_PIXEL_MODE_MONO ? 0 : 3,
0, x1, y1);
}
return 0;
}
static int draw_text(AVFilterContext *ctx, AVFrame *frame,
int width, int height)
{
DrawTextContext *s = ctx->priv;
AVFilterLink *inlink = ctx->inputs[0];
uint32_t code = 0, prev_code = 0;
int x = 0, y = 0, i = 0, ret;
int max_text_line_w = 0, len;
int box_w, box_h;
char *text = s->text;
uint8_t *p;
int y_min = 32000, y_max = -32000;
int x_min = 32000, x_max = -32000;
FT_Vector delta;
Glyph *glyph = NULL, *prev_glyph = NULL;
Glyph dummy = { 0 };
time_t now = time(0);
struct tm ltime;
AVBPrint *bp = &s->expanded_text;
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 = expand_text(ctx)) < 0)
return ret;
break;
case EXP_STRFTIME:
localtime_r(&now, &ltime);
av_bprint_strftime(bp, s->text, &ltime);
break;
}
if (s->tc_opt_string) {
char tcbuf[AV_TIMECODE_STR_SIZE];
av_timecode_make_string(&s->tc, tcbuf, inlink->frame_count);
av_bprint_clear(bp);
av_bprintf(bp, "%s%s", s->text, tcbuf);
}
if (!av_bprint_is_complete(bp))
return AVERROR(ENOMEM);
text = s->expanded_text.str;
if ((len = s->expanded_text.len) > s->nb_positions) {
if (!(s->positions =
av_realloc(s->positions, len*sizeof(*s->positions))))
return AVERROR(ENOMEM);
s->nb_positions = len;
}
x = 0;
y = 0;
/* load and cache glyphs */
for (i = 0, p = text; *p; i++) {
GET_UTF8(code, *p++, continue;);
/* get glyph */
dummy.code = code;
glyph = av_tree_find(s->glyphs, &dummy, glyph_cmp, NULL);
if (!glyph) {
load_glyph(ctx, &glyph, code);
}
y_min = FFMIN(glyph->bbox.yMin, y_min);
y_max = FFMAX(glyph->bbox.yMax, y_max);
x_min = FFMIN(glyph->bbox.xMin, x_min);
x_max = FFMAX(glyph->bbox.xMax, x_max);
}
s->max_glyph_h = y_max - y_min;
s->max_glyph_w = x_max - x_min;
/* compute and save position for each glyph */
glyph = NULL;
for (i = 0, p = text; *p; i++) {
GET_UTF8(code, *p++, continue;);
/* skip the \n in the sequence \r\n */
if (prev_code == '\r' && code == '\n')
continue;
prev_code = code;
if (is_newline(code)) {
max_text_line_w = FFMAX(max_text_line_w, x);
y += s->max_glyph_h;
x = 0;
continue;
}
/* get glyph */
prev_glyph = glyph;
dummy.code = code;
glyph = av_tree_find(s->glyphs, &dummy, glyph_cmp, NULL);
/* kerning */
if (s->use_kerning && prev_glyph && glyph->code) {
FT_Get_Kerning(s->face, prev_glyph->code, glyph->code,
ft_kerning_default, &delta);
x += delta.x >> 6;
}
/* save position */
s->positions[i].x = x + glyph->bitmap_left;
s->positions[i].y = y - glyph->bitmap_top + y_max;
if (code == '\t') x = (x / s->tabsize + 1)*s->tabsize;
else x += glyph->advance;
}
max_text_line_w = FFMAX(x, max_text_line_w);
s->var_values[VAR_TW] = s->var_values[VAR_TEXT_W] = max_text_line_w;
s->var_values[VAR_TH] = s->var_values[VAR_TEXT_H] = y + s->max_glyph_h;
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 ] = y_max;
s->var_values[VAR_MAX_GLYPH_D] = s->var_values[VAR_DESCENT] = y_min;
s->var_values[VAR_LINE_H] = s->var_values[VAR_LH] = s->max_glyph_h;
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);
s->x = s->var_values[VAR_X] = av_expr_eval(s->x_pexpr, s->var_values, &s->prng);
s->draw = av_expr_eval(s->draw_pexpr, s->var_values, &s->prng);
if(!s->draw)
return 0;
box_w = FFMIN(width - 1 , max_text_line_w);
box_h = FFMIN(height - 1, y + s->max_glyph_h);
/* draw box */
if (s->draw_box)
ff_blend_rectangle(&s->dc, &s->boxcolor,
frame->data, frame->linesize, width, height,
s->x, s->y, box_w, box_h);
if (s->shadowx || s->shadowy) {
if ((ret = draw_glyphs(s, frame, width, height, s->shadowcolor.rgba,
&s->shadowcolor, s->shadowx, s->shadowy)) < 0)
return ret;
}
if ((ret = draw_glyphs(s, frame, width, height, s->fontcolor.rgba,
&s->fontcolor, 0, 0)) < 0)
return ret;
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;
if (s->reload)
if ((ret = load_textfile(ctx)) < 0)
return ret;
s->var_values[VAR_N] = inlink->frame_count+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;
s->metadata = av_frame_get_metadata(frame);
draw_text(ctx, frame, frame->width, frame->height);
av_log(ctx, AV_LOG_DEBUG, "n:%d t:%f text_w:%d text_h:%d x:%d y:%d\n",
(int)s->var_values[VAR_N], s->var_values[VAR_T],
(int)s->var_values[VAR_TEXT_W], (int)s->var_values[VAR_TEXT_H],
s->x, s->y);
return ff_filter_frame(outlink, frame);
}
static const AVFilterPad avfilter_vf_drawtext_inputs[] = {
{
.name = "default",
.type = AVMEDIA_TYPE_VIDEO,
.get_video_buffer = ff_null_get_video_buffer,
.filter_frame = filter_frame,
.config_props = config_input,
.needs_writable = 1,
},
{ NULL }
};
static const AVFilterPad avfilter_vf_drawtext_outputs[] = {
{
.name = "default",
.type = AVMEDIA_TYPE_VIDEO,
},
{ NULL }
};
AVFilter avfilter_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,
.query_formats = query_formats,
.inputs = avfilter_vf_drawtext_inputs,
.outputs = avfilter_vf_drawtext_outputs,
.process_command = command,
};