lavfi: split frame_count between input and output.

AVFilterLink.frame_count is supposed to count the number of frames
that were passed on the link, but with min_samples, that number is
not always the same for the source and destination filters.
With the addition of a FIFO on the link, the difference will become
more significant.

Split the variable in two: frame_count_in counts the number of
frames that entered the link, frame_count_out counts the number
of frames that were sent to the destination filter.

1 files changed, 2 insertions, 2 deletions

diff --git a/libavfilter/vf_drawtext.c b/libavfilter/vf_drawtext.c
index 331d6b92a8..649240b010 100644
--- a/libavfilter/vf_drawtext.c
+++ b/libavfilter/vf_drawtext.c
@@ -1184,7 +1184,7 @@ static int draw_text(AVFilterContext *ctx, AVFrame *frame,
 
     if (s->tc_opt_string) {
         char tcbuf[AV_TIMECODE_STR_SIZE];
-        av_timecode_make_string(&s->tc, tcbuf, inlink->frame_count);
+        av_timecode_make_string(&s->tc, tcbuf, inlink->frame_count_out);
         av_bprint_clear(bp);
         av_bprintf(bp, "%s%s", s->text, tcbuf);
     }
@@ -1345,7 +1345,7 @@ static int filter_frame(AVFilterLink *inlink, AVFrame *frame)
 #endif
     }
 
-    s->var_values[VAR_N] = inlink->frame_count+s->start_number;
+    s->var_values[VAR_N] = inlink->frame_count_out + s->start_number;
     s->var_values[VAR_T] = frame->pts == AV_NOPTS_VALUE ?
         NAN : frame->pts * av_q2d(inlink->time_base);