generic-library/ffmpeg
1
0
Fork 0
Code Issues Pull Requests Releases Wiki Activity

drawtext: add 'fix_bounds' option on coords fixing

Browse Source 
Before, drawtext filter deliberately altered given text coordinates if
text didn't fully fit on the picture. This breaks the use case of
scrolling large text, e.g. movie closing credits.
Add 'fix_bounds', to make it usable in such cases (by setting its value to 0).
Default behavior is not changed, and non-fitting text coords are fixed.

Signed-off-by: Anton Khirnov <anton@khirnov.net>
This commit is contained in:
Andrey Utkin 2012-02-05 14:41:01 +02:00 committed by Anton Khirnov
parent 2b43dfce36
commit e496c45d9b
2 changed files with 14 additions and 6 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

3
doc/filters.texi
View File

@ -598,6 +598,9 @@ libfreetype flags.
@item tabsize
The size in number of spaces to use for rendering the tab.
Default value is 4.
@item fix_bounds
If true, check and fix text coords to avoid clipping.
@end table
For example the command:

17
libavfilter/vf_drawtext.c
View File

@ -122,6 +122,7 @@ typedef struct {
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
FT_Library library; ///< freetype font library handle
FT_Face face; ///< freetype font face handle
@ -157,6 +158,8 @@ static const AVOption drawtext_options[]= {
{"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 },
{"draw", "if false do not draw", OFFSET(d_expr), AV_OPT_TYPE_STRING, {.str="1"}, CHAR_MIN, CHAR_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" },
@ -828,12 +831,14 @@ static void start_frame(AVFilterLink *inlink, AVFilterBufferRef *inpicref)
normalize_double(&dtext->x, dtext->var_values[VAR_X]);
normalize_double(&dtext->y, dtext->var_values[VAR_Y]);
if (dtext->x < 0) dtext->x = 0;
if (dtext->y < 0) dtext->y = 0;
if ((unsigned)dtext->x + (unsigned)dtext->w > inlink->w)
dtext->x = inlink->w - dtext->w;
if ((unsigned)dtext->y + (unsigned)dtext->h > inlink->h)
dtext->y = inlink->h - dtext->h;
if (dtext->fix_bounds) {
if (dtext->x < 0) dtext->x = 0;
if (dtext->y < 0) dtext->y = 0;
if ((unsigned)dtext->x + (unsigned)dtext->w > inlink->w)
dtext->x = inlink->w - dtext->w;
if ((unsigned)dtext->y + (unsigned)dtext->h > inlink->h)
dtext->y = inlink->h - dtext->h;
}
dtext->x &= ~((1 << dtext->hsub) - 1);
dtext->y &= ~((1 << dtext->vsub) - 1);