On Mon, Jun 19, 2023 at 6:34 PM Mark Ren <mark.re...@gmail.com> wrote:
> When enabled it will add pixels (or subtract if given a negative value) > between each letters, > set use_kerning to false, > and add the pixels to text_w. > Conflicts with big drawtext filter set that will be pushed soon. > > Signed-off-by: Mark Ren <mark.re...@gmail.com> > --- > libavfilter/vf_drawtext.c | 24 ++++++++++++++++++++---- > 1 file changed, 20 insertions(+), 4 deletions(-) > > diff --git a/libavfilter/vf_drawtext.c b/libavfilter/vf_drawtext.c > index 71ab851462..ec8313820d 100644 > --- a/libavfilter/vf_drawtext.c > +++ b/libavfilter/vf_drawtext.c > @@ -183,6 +183,7 @@ typedef struct DrawTextContext { > unsigned int fontsize; ///< font size to use > unsigned int default_fontsize; ///< default font size to use > > + int letter_spacing; ///< letter spacing in pixels > int line_spacing; ///< lines spacing in pixels > short int draw_box; ///< draw box around text - true or > false > int boxborderw; ///< box border width > @@ -208,6 +209,8 @@ typedef struct DrawTextContext { > char *a_expr; > AVExpr *a_pexpr; > int alpha; > + char* letter_spacing_expr; ///< expression for letter spacing > + AVExpr* letter_spacing_pexpr; ///< parsed expression for letter > spacing > AVLFG prng; ///< random > char *tc_opt_string; ///< specified timecode option string > AVRational tc_rate; ///< frame rate for timecode > @@ -237,6 +240,7 @@ static const AVOption drawtext_options[]= { > {"shadowcolor", "set shadow color", OFFSET(shadowcolor.rgba), > AV_OPT_TYPE_COLOR, {.str="black"}, 0, 0, FLAGS}, > {"box", "set box", OFFSET(draw_box), > AV_OPT_TYPE_BOOL, {.i64=0}, 0, 1 , FLAGS}, > {"boxborderw", "set box border width", OFFSET(boxborderw), > AV_OPT_TYPE_INT, {.i64=0}, INT_MIN, INT_MAX , FLAGS}, > + {"letter_spacing", "set letter spacing in pixels", > OFFSET(letter_spacing_expr), AV_OPT_TYPE_STRING, {.str="0"}, 0, 0, FLAGS}, > {"line_spacing", "set line spacing in pixels", > OFFSET(line_spacing), AV_OPT_TYPE_INT, {.i64=0}, INT_MIN, > INT_MAX,FLAGS}, > {"fontsize", "set font size", OFFSET(fontsize_expr), > AV_OPT_TYPE_STRING, {.str=NULL}, 0, 0 , FLAGS}, > {"x", "set x expression", OFFSET(x_expr), > AV_OPT_TYPE_STRING, {.str="0"}, 0, 0, FLAGS}, > @@ -812,7 +816,7 @@ static av_cold int init(AVFilterContext *ctx) > FT_STROKER_LINEJOIN_ROUND, 0); > } > > - s->use_kerning = FT_HAS_KERNING(s->face); > + s->use_kerning = FT_HAS_KERNING(s->face) && !s->letter_spacing; > > /* load the fallback glyph with code 0 */ > load_glyph(ctx, NULL, 0); > @@ -857,8 +861,9 @@ static av_cold void uninit(AVFilterContext *ctx) > av_expr_free(s->y_pexpr); > av_expr_free(s->a_pexpr); > av_expr_free(s->fontsize_pexpr); > + av_expr_free(s->letter_spacing_pexpr); > > - s->x_pexpr = s->y_pexpr = s->a_pexpr = s->fontsize_pexpr = NULL; > + s->x_pexpr = s->y_pexpr = s->a_pexpr = s->fontsize_pexpr = > s->letter_spacing_pexpr = NULL; > > av_freep(&s->positions); > s->nb_positions = 0; > @@ -903,13 +908,16 @@ static int config_input(AVFilterLink *inlink) > 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; > + av_expr_free(s->letter_spacing_pexpr); > + s->x_pexpr = s->y_pexpr = s->a_pexpr = s->letter_spacing_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 || > + (ret = av_expr_parse(&s->letter_spacing_pexpr, expr = > s->letter_spacing_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); > @@ -1525,6 +1533,9 @@ continue_on_invalid2: > dummy.fontsize = s->fontsize; > glyph = av_tree_find(s->glyphs, &dummy, glyph_cmp, NULL); > > + /* letter spacing */ > + x += s->letter_spacing; > + > /* kerning */ > if (s->use_kerning && prev_glyph && glyph->code) { > FT_Get_Kerning(s->face, prev_glyph->code, glyph->code, > @@ -1539,7 +1550,12 @@ continue_on_invalid2: > else x += glyph->advance; > } > > - max_text_line_w = FFMAX(x, max_text_line_w); > + s->letter_spacing = av_expr_eval(s->letter_spacing_pexpr, > s->var_values, &s->prng); > + if (s->letter_spacing < 0) { > + max_text_line_w = x+ s->letter_spacing; > + } else { > + max_text_line_w = FFMAX(x, max_text_line_w) + s->letter_spacing; > + } > > 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; > -- > 2.40.1 > > _______________________________________________ > ffmpeg-devel mailing list > ffmpeg-devel@ffmpeg.org > https://ffmpeg.org/mailman/listinfo/ffmpeg-devel > > To unsubscribe, visit link above, or email > ffmpeg-devel-requ...@ffmpeg.org with subject "unsubscribe". > _______________________________________________ ffmpeg-devel mailing list ffmpeg-devel@ffmpeg.org https://ffmpeg.org/mailman/listinfo/ffmpeg-devel To unsubscribe, visit link above, or email ffmpeg-devel-requ...@ffmpeg.org with subject "unsubscribe".