/*
* 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/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 "video.h"
#undef time
#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",
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_VARS_NB
};
typedef struct {
const AVClass *class;
int reinit; ///< tells if the filter is being reinited
uint8_t *fontfile; ///< font to be used
uint8_t *text; ///< text to be drawn
uint8_t *expanded_text; ///< used to contain the strftime()-expanded text
size_t expanded_text_size; ///< size in bytes of the expanded_text buffer
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
char *fontcolor_string; ///< font color as string
char *boxcolor_string; ///< box color as string
char *shadowcolor_string; ///< shadow color as string
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 frame_id;
} DrawTextContext;
#define OFFSET(x) offsetof(DrawTextContext, x)
static const AVOption drawtext_options[]= {
{"fontfile", "set font file", OFFSET(fontfile), AV_OPT_TYPE_STRING, {.str=NULL}, CHAR_MIN, CHAR_MAX },
{"text", "set text", OFFSET(text), AV_OPT_TYPE_STRING, {.str=NULL}, CHAR_MIN, CHAR_MAX },
{"textfile", "set text file", OFFSET(textfile), AV_OPT_TYPE_STRING, {.str=NULL}, CHAR_MIN, CHAR_MAX },
{"fontcolor", "set foreground color", OFFSET(fontcolor_string), AV_OPT_TYPE_STRING, {.str="black"}, CHAR_MIN, CHAR_MAX },
{"boxcolor", "set box color", OFFSET(boxcolor_string), AV_OPT_TYPE_STRING, {.str="white"}, CHAR_MIN, CHAR_MAX },
{"shadowcolor", "set shadow color", OFFSET(shadowcolor_string), AV_OPT_TYPE_STRING, {.str="black"}, CHAR_MIN, CHAR_MAX },
{"box", "set box", OFFSET(draw_box), AV_OPT_TYPE_INT, {.dbl=0}, 0, 1 },
{"fontsize", "set font size", OFFSET(fontsize), AV_OPT_TYPE_INT, {.dbl=0}, 0, INT_MAX },
{"x", "set x expression", OFFSET(x_expr), AV_OPT_TYPE_STRING, {.str="0"}, CHAR_MIN, CHAR_MAX },
{"y", "set y expression", OFFSET(y_expr), AV_OPT_TYPE_STRING, {.str="0"}, CHAR_MIN, CHAR_MAX },
{"shadowx", "set x", OFFSET(shadowx), AV_OPT_TYPE_INT, {.dbl=0}, INT_MIN, INT_MAX },
{"shadowy", "set y", OFFSET(shadowy), AV_OPT_TYPE_INT, {.dbl=0}, INT_MIN, INT_MAX },
{"tabsize", "set tab size", OFFSET(tabsize), AV_OPT_TYPE_INT, {.dbl=4}, 0, INT_MAX },
{"basetime", "set base time", OFFSET(basetime), AV_OPT_TYPE_INT64, {.dbl=AV_NOPTS_VALUE}, INT64_MIN, INT64_MAX },
{"draw", "if false do not draw", OFFSET(draw_expr), AV_OPT_TYPE_STRING, {.str="1"}, CHAR_MIN, CHAR_MAX },
{"timecode", "set initial timecode", OFFSET(tc_opt_string), AV_OPT_TYPE_STRING, {.str=NULL}, CHAR_MIN, CHAR_MAX },
{"tc24hmax", "set 24 hours max (timecode only)", OFFSET(tc24hmax), AV_OPT_TYPE_INT, {.dbl=0}, 0, 1 },
{"timecode_rate", "set rate (timecode only)", OFFSET(tc_rate), AV_OPT_TYPE_RATIONAL, {.dbl=0}, 0, INT_MAX },
{"r", "set rate (timecode only)", OFFSET(tc_rate), AV_OPT_TYPE_RATIONAL, {.dbl=0}, 0, INT_MAX },
{"rate", "set rate (timecode only)", OFFSET(tc_rate), AV_OPT_TYPE_RATIONAL, {.dbl=0}, 0, INT_MAX },
{"fix_bounds", "if true, check and fix text coords to avoid clipping",
OFFSET(fix_bounds), AV_OPT_TYPE_INT, {.dbl=1}, 0, 1 },
/* FT_LOAD_* flags */
{"ft_load_flags", "set font loading flags for libfreetype", OFFSET(ft_load_flags), AV_OPT_TYPE_FLAGS, {.dbl=FT_LOAD_DEFAULT|FT_LOAD_RENDER}, 0, INT_MAX, 0, "ft_load_flags" },
{"default", "set default", 0, AV_OPT_TYPE_CONST, {.dbl=FT_LOAD_DEFAULT}, INT_MIN, INT_MAX, 0, "ft_load_flags" },
{"no_scale", "set no_scale", 0, AV_OPT_TYPE_CONST, {.dbl=FT_LOAD_NO_SCALE}, INT_MIN, INT_MAX, 0, "ft_load_flags" },
{"no_hinting", "set no_hinting", 0, AV_OPT_TYPE_CONST, {.dbl=FT_LOAD_NO_HINTING}, INT_MIN, INT_MAX, 0, "ft_load_flags" },
{"render", "set render", 0, AV_OPT_TYPE_CONST, {.dbl=FT_LOAD_RENDER}, INT_MIN, INT_MAX, 0, "ft_load_flags" },
{"no_bitmap", "set no_bitmap", 0, AV_OPT_TYPE_CONST, {.dbl=FT_LOAD_NO_BITMAP}, INT_MIN, INT_MAX, 0, "ft_load_flags" },
{"vertical_layout", "set vertical_layout", 0, AV_OPT_TYPE_CONST, {.dbl=FT_LOAD_VERTICAL_LAYOUT}, INT_MIN, INT_MAX, 0, "ft_load_flags" },
{"force_autohint", "set force_autohint", 0, AV_OPT_TYPE_CONST, {.dbl=FT_LOAD_FORCE_AUTOHINT}, INT_MIN, INT_MAX, 0, "ft_load_flags" },
{"crop_bitmap", "set crop_bitmap", 0, AV_OPT_TYPE_CONST, {.dbl=FT_LOAD_CROP_BITMAP}, INT_MIN, INT_MAX, 0, "ft_load_flags" },
{"pedantic", "set pedantic", 0, AV_OPT_TYPE_CONST, {.dbl=FT_LOAD_PEDANTIC}, INT_MIN, INT_MAX, 0, "ft_load_flags" },
{"ignore_global_advance_width", "set ignore_global_advance_width", 0, AV_OPT_TYPE_CONST, {.dbl=FT_LOAD_IGNORE_GLOBAL_ADVANCE_WIDTH}, INT_MIN, INT_MAX, 0, "ft_load_flags" },
{"no_recurse", "set no_recurse", 0, AV_OPT_TYPE_CONST, {.dbl=FT_LOAD_NO_RECURSE}, INT_MIN, INT_MAX, 0, "ft_load_flags" },
{"ignore_transform", "set ignore_transform", 0, AV_OPT_TYPE_CONST, {.dbl=FT_LOAD_IGNORE_TRANSFORM}, INT_MIN, INT_MAX, 0, "ft_load_flags" },
{"monochrome", "set monochrome", 0, AV_OPT_TYPE_CONST, {.dbl=FT_LOAD_MONOCHROME}, INT_MIN, INT_MAX, 0, "ft_load_flags" },
{"linear_design", "set linear_design", 0, AV_OPT_TYPE_CONST, {.dbl=FT_LOAD_LINEAR_DESIGN}, INT_MIN, INT_MAX, 0, "ft_load_flags" },
{"no_autohint", "set no_autohint", 0, AV_OPT_TYPE_CONST, {.dbl=FT_LOAD_NO_AUTOHINT}, INT_MIN, INT_MAX, 0, "ft_load_flags" },
{NULL},
};
static const char *drawtext_get_name(void *ctx)
{
return "drawtext";
}
static const AVClass drawtext_class = {
"DrawTextContext",
drawtext_get_name,
drawtext_options
};
#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 *dtext = ctx->priv;
Glyph *glyph;
struct AVTreeNode *node = NULL;
int ret;
/* load glyph into dtext->face->glyph */
if (FT_Load_Char(dtext->face, code, dtext->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(dtext->face->glyph, glyph->glyph)) {
ret = AVERROR(EINVAL);
goto error;
}
glyph->bitmap = dtext->face->glyph->bitmap;
glyph->bitmap_left = dtext->face->glyph->bitmap_left;
glyph->bitmap_top = dtext->face->glyph->bitmap_top;
glyph->advance = dtext->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_mallocz(av_tree_node_size))) {
ret = AVERROR(ENOMEM);
goto error;
}
av_tree_insert(&dtext->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 *dtext = ctx->priv;
int err;
err = FT_New_Face(dtext->library, path, index, &dtext->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 *dtext = 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(dtext->fontfile ? dtext->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 (!dtext->fontsize)
dtext->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 *dtext = 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, dtext->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",
dtext->fontfile, error);
return err;
}
static av_cold int init(AVFilterContext *ctx, const char *args, void *opaque)
{
int err;
DrawTextContext *dtext = ctx->priv;
Glyph *glyph;
dtext->class = &drawtext_class;
av_opt_set_defaults(dtext);
if ((err = (av_set_options_string(dtext, args, "=", ":"))) < 0) {
av_log(ctx, AV_LOG_ERROR, "Error parsing options string: '%s'\n", args);
return err;
}
if (!dtext->fontfile && !CONFIG_FONTCONFIG) {
av_log(ctx, AV_LOG_ERROR, "No font filename provided\n");
return AVERROR(EINVAL);
}
if (dtext->textfile) {
uint8_t *textbuf;
size_t textbuf_size;
if (dtext->text) {
av_log(ctx, AV_LOG_ERROR,
"Both text and text file provided. Please provide only one\n");
return AVERROR(EINVAL);
}
if ((err = av_file_map(dtext->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",
dtext->textfile);
return err;
}
if (!(dtext->text = av_malloc(textbuf_size+1)))
return AVERROR(ENOMEM);
memcpy(dtext->text, textbuf, textbuf_size);
dtext->text[textbuf_size] = 0;
av_file_unmap(textbuf, textbuf_size);
}
if (dtext->tc_opt_string) {
int ret = av_timecode_init_from_string(&dtext->tc, dtext->tc_rate,
dtext->tc_opt_string, ctx);
if (ret < 0)
return ret;
if (dtext->tc24hmax)
dtext->tc.flags |= AV_TIMECODE_FLAG_24HOURSMAX;
if (!dtext->text)
dtext->text = av_strdup("");
}
if (!dtext->text) {
av_log(ctx, AV_LOG_ERROR,
"Either text, a valid file or a timecode must be provided\n");
return AVERROR(EINVAL);
}
if ((err = av_parse_color(dtext->fontcolor.rgba, dtext->fontcolor_string, -1, ctx))) {
av_log(ctx, AV_LOG_ERROR,
"Invalid font color '%s'\n", dtext->fontcolor_string);
return err;
}
if ((err = av_parse_color(dtext->boxcolor.rgba, dtext->boxcolor_string, -1, ctx))) {
av_log(ctx, AV_LOG_ERROR,
"Invalid box color '%s'\n", dtext->boxcolor_string);
return err;
}
if ((err = av_parse_color(dtext->shadowcolor.rgba, dtext->shadowcolor_string, -1, ctx))) {
av_log(ctx, AV_LOG_ERROR,
"Invalid shadow color '%s'\n", dtext->shadowcolor_string);
return err;
}
if ((err = FT_Init_FreeType(&(dtext->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 (!dtext->fontsize)
dtext->fontsize = 16;
if ((err = FT_Set_Pixel_Sizes(dtext->face, 0, dtext->fontsize))) {
av_log(ctx, AV_LOG_ERROR, "Could not set font size to %d pixels: %s\n",
dtext->fontsize, FT_ERRMSG(err));
return AVERROR(EINVAL);
}
dtext->use_kerning = FT_HAS_KERNING(dtext->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;
}
dtext->tabsize *= glyph->advance;
return 0;
}
static int query_formats(AVFilterContext *ctx)
{
avfilter_set_common_pixel_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 *dtext = ctx->priv;
av_expr_free(dtext->x_pexpr); dtext->x_pexpr = NULL;
av_expr_free(dtext->y_pexpr); dtext->y_pexpr = NULL;
av_expr_free(dtext->draw_pexpr); dtext->draw_pexpr = NULL;
av_freep(&dtext->boxcolor_string);
av_freep(&dtext->expanded_text);
av_freep(&dtext->fontcolor_string);
av_freep(&dtext->fontfile);
av_freep(&dtext->shadowcolor_string);
av_freep(&dtext->text);
av_freep(&dtext->x_expr);
av_freep(&dtext->y_expr);
av_freep(&dtext->draw_expr);
av_freep(&dtext->positions);
dtext->nb_positions = 0;
av_tree_enumerate(dtext->glyphs, NULL, NULL, glyph_enu_free);
av_tree_destroy(dtext->glyphs);
dtext->glyphs = NULL;
FT_Done_Face(dtext->face);
FT_Done_FreeType(dtext->library);
}
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 *dtext = ctx->priv;
int ret;
ff_draw_init(&dtext->dc, inlink->format, 0);
ff_draw_color(&dtext->dc, &dtext->fontcolor, dtext->fontcolor.rgba);
ff_draw_color(&dtext->dc, &dtext->shadowcolor, dtext->shadowcolor.rgba);
ff_draw_color(&dtext->dc, &dtext->boxcolor, dtext->boxcolor.rgba);
dtext->var_values[VAR_w] = dtext->var_values[VAR_W] = dtext->var_values[VAR_MAIN_W] = inlink->w;
dtext->var_values[VAR_h] = dtext->var_values[VAR_H] = dtext->var_values[VAR_MAIN_H] = inlink->h;
dtext->var_values[VAR_SAR] = inlink->sample_aspect_ratio.num ? av_q2d(inlink->sample_aspect_ratio) : 1;
dtext->var_values[VAR_DAR] = (double)inlink->w / inlink->h * dtext->var_values[VAR_SAR];
dtext->var_values[VAR_HSUB] = 1 << dtext->dc.hsub_max;
dtext->var_values[VAR_VSUB] = 1 << dtext->dc.vsub_max;
dtext->var_values[VAR_X] = NAN;
dtext->var_values[VAR_Y] = NAN;
if (!dtext->reinit)
dtext->var_values[VAR_N] = 0;
dtext->var_values[VAR_T] = NAN;
av_lfg_init(&dtext->prng, av_get_random_seed());
if ((ret = av_expr_parse(&dtext->x_pexpr, dtext->x_expr, var_names,
NULL, NULL, fun2_names, fun2, 0, ctx)) < 0 ||
(ret = av_expr_parse(&dtext->y_pexpr, dtext->y_expr, var_names,
NULL, NULL, fun2_names, fun2, 0, ctx)) < 0 ||
(ret = av_expr_parse(&dtext->draw_pexpr, dtext->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 *dtext = ctx->priv;
if (!strcmp(cmd, "reinit")) {
int ret;
uninit(ctx);
dtext->reinit = 1;
if ((ret = init(ctx, arg, NULL)) < 0)
return ret;
return config_input(ctx->inputs[0]);
}
return AVERROR(ENOSYS);
}
static int draw_glyphs(DrawTextContext *dtext, AVFilterBufferRef *picref,
int width, int height, const uint8_t rgbcolor[4], FFDrawColor *color, int x, int y)
{
char *text = dtext->expanded_text;
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(dtext->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 = dtext->positions[i].x+dtext->x+x;
y1 = dtext->positions[i].y+dtext->y+y;
ff_blend_mask(&dtext->dc, color,
picref->data, picref->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, AVFilterBufferRef *picref,
int width, int height)
{
DrawTextContext *dtext = ctx->priv;
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 = dtext->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;
uint8_t *buf = dtext->expanded_text;
int buf_size = dtext->expanded_text_size;
if(dtext->basetime != AV_NOPTS_VALUE)
now= picref->pts*av_q2d(ctx->inputs[0]->time_base) + dtext->basetime/1000000;
if (!buf) {
buf_size = 2*strlen(dtext->text)+1;
buf = av_malloc(buf_size);
}
#if HAVE_LOCALTIME_R
localtime_r(&now, <ime);
#else
if(strchr(dtext->text, '%'))
ltime= *localtime(&now);
#endif
do {
*buf = 1;
if (strftime(buf, buf_size, dtext->text, <ime) != 0 || *buf == 0)
break;
buf_size *= 2;
} while ((buf = av_realloc(buf, buf_size)));
if (dtext->tc_opt_string) {
char tcbuf[AV_TIMECODE_STR_SIZE];
av_timecode_make_string(&dtext->tc, tcbuf, dtext->frame_id++);
buf = av_asprintf("%s%s", dtext->text, tcbuf);
}
if (!buf)
return AVERROR(ENOMEM);
text = dtext->expanded_text = buf;
dtext->expanded_text_size = buf_size;
if ((len = strlen(text)) > dtext->nb_positions) {
if (!(dtext->positions =
av_realloc(dtext->positions, len*sizeof(*dtext->positions))))
return AVERROR(ENOMEM);
dtext->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(dtext->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);
}
dtext->max_glyph_h = y_max - y_min;
dtext->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 += dtext->max_glyph_h;
x = 0;
continue;
}
/* get glyph */
prev_glyph = glyph;
dummy.code = code;
glyph = av_tree_find(dtext->glyphs, &dummy, glyph_cmp, NULL);
/* kerning */
if (dtext->use_kerning && prev_glyph && glyph->code) {
FT_Get_Kerning(dtext->face, prev_glyph->code, glyph->code,
ft_kerning_default, &delta);
x += delta.x >> 6;
}
/* save position */
dtext->positions[i].x = x + glyph->bitmap_left;
dtext->positions[i].y = y - glyph->bitmap_top + y_max;
if (code == '\t') x = (x / dtext->tabsize + 1)*dtext->tabsize;
else x += glyph->advance;
}
max_text_line_w = FFMAX(x, max_text_line_w);
dtext->var_values[VAR_TW] = dtext->var_values[VAR_TEXT_W] = max_text_line_w;
dtext->var_values[VAR_TH] = dtext->var_values[VAR_TEXT_H] = y + dtext->max_glyph_h;
dtext->var_values[VAR_MAX_GLYPH_W] = dtext->max_glyph_w;
dtext->var_values[VAR_MAX_GLYPH_H] = dtext->max_glyph_h;
dtext->var_values[VAR_MAX_GLYPH_A] = dtext->var_values[VAR_ASCENT ] = y_max;
dtext->var_values[VAR_MAX_GLYPH_D] = dtext->var_values[VAR_DESCENT] = y_min;
dtext->var_values[VAR_LINE_H] = dtext->var_values[VAR_LH] = dtext->max_glyph_h;
dtext->x = dtext->var_values[VAR_X] = av_expr_eval(dtext->x_pexpr, dtext->var_values, &dtext->prng);
dtext->y = dtext->var_values[VAR_Y] = av_expr_eval(dtext->y_pexpr, dtext->var_values, &dtext->prng);
dtext->x = dtext->var_values[VAR_X] = av_expr_eval(dtext->x_pexpr, dtext->var_values, &dtext->prng);
dtext->draw = av_expr_eval(dtext->draw_pexpr, dtext->var_values, &dtext->prng);
if(!dtext->draw)
return 0;
box_w = FFMIN(width - 1 , max_text_line_w);
box_h = FFMIN(height - 1, y + dtext->max_glyph_h);
/* draw box */
if (dtext->draw_box)
ff_blend_rectangle(&dtext->dc, &dtext->boxcolor,
picref->data, picref->linesize, width, height,
dtext->x, dtext->y, box_w, box_h);
if (dtext->shadowx || dtext->shadowy) {
if ((ret = draw_glyphs(dtext, picref, width, height, dtext->shadowcolor.rgba,
&dtext->shadowcolor, dtext->shadowx, dtext->shadowy)) < 0)
return ret;
}
if ((ret = draw_glyphs(dtext, picref, width, height, dtext->fontcolor.rgba,
&dtext->fontcolor, 0, 0)) < 0)
return ret;
return 0;
}
static void null_draw_slice(AVFilterLink *link, int y, int h, int slice_dir) { }
static void end_frame(AVFilterLink *inlink)
{
AVFilterContext *ctx = inlink->dst;
AVFilterLink *outlink = ctx->outputs[0];
DrawTextContext *dtext = ctx->priv;
AVFilterBufferRef *picref = inlink->cur_buf;
dtext->var_values[VAR_T] = picref->pts == AV_NOPTS_VALUE ?
NAN : picref->pts * av_q2d(inlink->time_base);
draw_text(ctx, picref, picref->video->w, picref->video->h);
av_log(ctx, AV_LOG_DEBUG, "n:%d t:%f text_w:%d text_h:%d x:%d y:%d\n",
(int)dtext->var_values[VAR_N], dtext->var_values[VAR_T],
(int)dtext->var_values[VAR_TEXT_W], (int)dtext->var_values[VAR_TEXT_H],
dtext->x, dtext->y);
dtext->var_values[VAR_N] += 1.0;
avfilter_draw_slice(outlink, 0, picref->video->h, 1);
avfilter_end_frame(outlink);
}
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),
.init = init,
.uninit = uninit,
.query_formats = query_formats,
.inputs = (const AVFilterPad[]) {{ .name = "default",
.type = AVMEDIA_TYPE_VIDEO,
.get_video_buffer = ff_null_get_video_buffer,
.start_frame = ff_null_start_frame,
.draw_slice = null_draw_slice,
.end_frame = end_frame,
.config_props = config_input,
.min_perms = AV_PERM_WRITE |
AV_PERM_READ,
.rej_perms = AV_PERM_PRESERVE },
{ .name = NULL}},
.outputs = (const AVFilterPad[]) {{ .name = "default",
.type = AVMEDIA_TYPE_VIDEO, },
{ .name = NULL}},
.process_command = command,
};