lavfi/drawtext: add support for printing frame numbers

Fix trac ticket #1949.
This commit is contained in:
Stefano Sabatini 2012-11-22 12:08:45 +01:00
parent dcbf72836c
commit eb87b340e8
3 changed files with 15 additions and 1 deletions

View File

@ -2083,6 +2083,9 @@ It can accept an argument: a strftime() format string.
The time at which the filter is running, expressed in the local time zone.
It can accept an argument: a strftime() format string.
@item n, frame_num
The frame number, starting from 0.
@item pts
The timestamp of the current frame, in seconds, with microsecond accuracy.

View File

@ -30,7 +30,7 @@
#define LIBAVFILTER_VERSION_MAJOR 3
#define LIBAVFILTER_VERSION_MINOR 23
#define LIBAVFILTER_VERSION_MICRO 101
#define LIBAVFILTER_VERSION_MICRO 102
#define LIBAVFILTER_VERSION_INT AV_VERSION_INT(LIBAVFILTER_VERSION_MAJOR, \
LIBAVFILTER_VERSION_MINOR, \

View File

@ -611,6 +611,15 @@ static int func_pts(AVFilterContext *ctx, AVBPrint *bp,
return 0;
}
static int func_frame_num(AVFilterContext *ctx, AVBPrint *bp,
char *fct, unsigned argc, char **argv, int tag)
{
DrawTextContext *dtext = ctx->priv;
av_bprintf(bp, "%d", (int)dtext->var_values[VAR_N]);
return 0;
}
#if !HAVE_LOCALTIME_R
static void localtime_r(const time_t *t, struct tm *tm)
{
@ -643,6 +652,8 @@ static const struct drawtext_function {
{ "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 },
};
static int eval_function(AVFilterContext *ctx, AVBPrint *bp, char *fct,