[FFmpeg-devel] [PATCH] added expr evaluation to drawtext - fontsize
Brett Harrison
brett.harrison at zyamusic.com
Tue Aug 30 00:23:44 EEST 2016
Before I fix the patch, can you clarify the intended functionality?
The docs say that 16 is the default fontsize, however if
CONFIG_LIBFONTCONFIG is configured and ffmpeg if called with:
-vf drawtext=text=abc:fontcolor=white
on my system the font used will be /opt/X11/share/fonts/TTF/Vera.ttf (the
default chosen by libfontconfig) and the fontsize will be set to 12.
However if ffmpeg is called with:
-vf
drawtext=text=abc:fontcolor=white:fontfile=/opt/X11/share/fonts/TTF/Vera.ttf
This is the same font that libfontconfig used, however this time fontsize
16 is used as stated in the docs.
The difference is this line of code in load_font_fontconfig
if (!s->fontsize)
s->fontsize = size + 0.5;
I didn't set the fontsize in either command, but the output was different.
Do we want to keep this as is?
On Sun, Aug 28, 2016 at 6:09 PM, Michael Niedermayer <michael at niedermayer.cc
> wrote:
> On Sat, Aug 27, 2016 at 04:30:05PM -0700, Brett Harrison wrote:
> > Fixed patch based on comments.
> >
> > This time attaching patch file.
> >
> > On Sat, Aug 27, 2016 at 6:21 AM, Moritz Barsnick <barsnick at gmx.net>
> wrote:
> >
> > > On Fri, Aug 26, 2016 at 14:37:42 -0700, Brett Harrison wrote:
> > >
> > > > + if (diff != 0) {
> > > > + return diff > 0 ? 1 : diff < 0 ? -1 : 0;
> > > > + }
> > >
> > > If diff != 0, it can only be >0 or <0, nothing else:
> > > if (diff != 0)
> > > return diff > 0 ? 1 : -1;
> > > (And you can drop the curly brackets.)
> > >
> > > > + else {
> > > > + int64_t diff = (int64_t)a->fontsize - (int64_t)bb->fontsize;
> > > > + return diff > 0 ? 1 : diff < 0 ? -1 : 0;
> > > > + }
> > >
> > > There's a macro for this:
> > > else
> > > return FFDIFFSIGN((int64_t)a->fontsize,
> (int64_t)bb->fontsize);
> > >
> > > Moritz
> > > _______________________________________________
> > > ffmpeg-devel mailing list
> > > ffmpeg-devel at ffmpeg.org
> > > http://ffmpeg.org/mailman/listinfo/ffmpeg-devel
> > >
>
> > vf_drawtext.c | 86 ++++++++++++++++++++++++++++++
> +++++++++++++++++++++++-----
> > 1 file changed, 79 insertions(+), 7 deletions(-)
> > dd219d9b4d4f02ca4299a0bfd6ea3d5c15545f2b 0001-added-expr-evaluation-to-
> drawtext-fontsize.patch
> > From 5c9d7d18a5d2f15f48605021d7f5a7890a318cc4 Mon Sep 17 00:00:00 2001
> > From: Brett Harrison <brett.harrison at musicmastermind.com>
> > Date: Fri, 26 Aug 2016 14:29:34 -0700
> > Subject: [PATCH] added expr evaluation to drawtext - fontsize
>
> this changes the output and fontsize when fontsize is not explicitly
> specified
>
> for example:
> -vf drawtext=text=abc:fontcolor=white
>
>
> >
> > ---
> > libavfilter/vf_drawtext.c | 86 ++++++++++++++++++++++++++++++
> +++++++++++++----
> > 1 file changed, 79 insertions(+), 7 deletions(-)
> >
> > diff --git a/libavfilter/vf_drawtext.c b/libavfilter/vf_drawtext.c
> > index 214aef0..5311e29 100644
> > --- a/libavfilter/vf_drawtext.c
> > +++ b/libavfilter/vf_drawtext.c
> > @@ -156,6 +156,8 @@ typedef struct DrawTextContext {
> > 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
> >
> > short int draw_box; ///< draw box around text - true or
> false
> > @@ -209,7 +211,7 @@ static const AVOption drawtext_options[]= {
> > {"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_BOOL, {.i64=0}, 0, 1 , FLAGS},
> > {"boxborderw", "set box border width", OFFSET(boxborderw),
> AV_OPT_TYPE_INT, {.i64=0}, INT_MIN, INT_MAX , FLAGS},
> > - {"fontsize", "set font size", OFFSET(fontsize),
> AV_OPT_TYPE_INT, {.i64=0}, 0, INT_MAX , FLAGS},
> > + {"fontsize", "set font size", OFFSET(fontsize_expr),
> AV_OPT_TYPE_STRING, {.str="16"}, CHAR_MIN, CHAR_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 shadow x offset", OFFSET(shadowx),
> AV_OPT_TYPE_INT, {.i64=0}, INT_MIN, INT_MAX , FLAGS},
> > @@ -280,6 +282,7 @@ typedef struct Glyph {
> > FT_Glyph glyph;
> > FT_Glyph border_glyph;
> > uint32_t code;
> > + unsigned int fontsize;
> > FT_Bitmap bitmap; ///< array holding bitmaps of font
> > FT_Bitmap border_bitmap; ///< array holding bitmaps of font border
> > FT_BBox bbox;
> > @@ -292,7 +295,11 @@ 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;
> > - return diff > 0 ? 1 : diff < 0 ? -1 : 0;
> > +
> > + if (diff != 0)
> > + return diff > 0 ? 1 : -1;
> > + else
> > + return FFDIFFSIGN((int64_t)a->fontsize,
> (int64_t)bb->fontsize);
> > }
> >
> > /**
> > @@ -316,6 +323,7 @@ static int load_glyph(AVFilterContext *ctx, Glyph
> **glyph_ptr, uint32_t code)
> > goto error;
> > }
> > glyph->code = code;
> > + glyph->fontsize = s->fontsize;
> >
> > if (FT_Get_Glyph(s->face->glyph, &glyph->glyph)) {
> > ret = AVERROR(EINVAL);
> > @@ -591,12 +599,62 @@ out:
> > }
> > #endif
> >
> > +static av_cold int set_fontsize(AVFilterContext *ctx)
> > +{
> > + int err;
> > + DrawTextContext *s = ctx->priv;
> > +
> > + if (s->face == NULL) {
> > + av_log(ctx, AV_LOG_ERROR, "Font not open\n");
> > + return AVERROR(EINVAL);
> > + }
> > +
> > + 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);
> > + }
> > +
> > + return 0;
> > +}
> > +
> > +static av_cold int update_fontsize(AVFilterContext *ctx)
> > +{
> > + DrawTextContext *s = ctx->priv;
> > + unsigned int fontsize = 16;
> > +
> > + double size = av_expr_eval(s->fontsize_pexpr, s->var_values,
> &s->prng);
> > +
> > + if (isnan(size))
> > + fontsize = 16;
>
> > + else if (round(size) <= 0)
> > + fontsize = 1;
> > + else
> > + fontsize = round(size);
>
> you should check fontsize not round(size) and then re-evaluate
> round(size), C doesnt gurantee that to be teh same
>
>
> > +
> > + // no change
> > + if (fontsize == s->fontsize) {
> > + return 0;
> > + }
>
> inconsistet indention and supeflous {}
>
>
> [...]
>
> > @@ -1084,6 +1148,7 @@ static int draw_glyphs(DrawTextContext *s, AVFrame
> *frame,
> > for (i = 0, p = text; *p; i++) {
> > FT_Bitmap bitmap;
> > Glyph dummy = { 0 };
> > +
> > GET_UTF8(code, *p++, continue;);
> >
> > /* skip new line chars, just go to new line */
>
> stray change
>
> [...]
>
>
> --
> Michael GnuPG fingerprint: 9FF2128B147EF6730BADF133611EC787040B0FAB
>
> I do not agree with what you have to say, but I'll defend to the death your
> right to say it. -- Voltaire
>
> _______________________________________________
> ffmpeg-devel mailing list
> ffmpeg-devel at ffmpeg.org
> http://ffmpeg.org/mailman/listinfo/ffmpeg-devel
>
>
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