From c11ef252e6ea1df9ed78944b129c313821ce219c Mon Sep 17 00:00:00 2001
From: Philip Gladstone <philipjsg@users.sourceforge.net>
Date: Mon, 2 Dec 2002 04:21:17 +0000
Subject: [PATCH] Fixed problem with frame rate reduction when capturing from a
source whose PTS does not start at zero. New code will fix that if the PTS is
more than 100 seconds from zero. This may well not be the right number, but
it is a big improvement over the current state.
Originally committed as revision 1297 to svn://svn.ffmpeg.org/ffmpeg/trunk
---
ffmpeg.c | 25 +++++++++++++++++++------
1 file changed, 19 insertions(+), 6 deletions(-)
diff --git a/ffmpeg.c b/ffmpeg.c
index 25cfba6f680..9defc3cf3b7 100644
--- a/ffmpeg.c
+++ b/ffmpeg.c
@@ -163,6 +163,7 @@ typedef struct AVOutputStream {
/* input pts and corresponding output pts
for A/V sync */
double sync_ipts;
+ double sync_ipts_offset;
INT64 sync_opts;
/* video only */
AVPicture pict_tmp; /* temporary image for resizing */
@@ -541,12 +542,24 @@ static void do_video_out(AVFormatContext *s,
double vdelta;
if (ost->sync_ipts != AV_NOPTS_VALUE) {
- vdelta = (double)(ost->st->pts.val) * s->pts_num / s->pts_den - ost->sync_ipts;
- if (vdelta < -AV_DELAY_MAX)
- nb_frames = 2;
- else if (vdelta > AV_DELAY_MAX)
- nb_frames = 0;
- //printf("vdelta=%f\n", vdelta);
+ vdelta = (double)(ost->st->pts.val) * s->pts_num / s->pts_den - (ost->sync_ipts - ost->sync_ipts_offset);
+ if (vdelta < 100 && vdelta > -100) {
+ if (vdelta < -AV_DELAY_MAX)
+ nb_frames = 2;
+ else if (vdelta > AV_DELAY_MAX)
+ nb_frames = 0;
+ } else {
+ ost->sync_ipts_offset -= vdelta;
+ }
+
+#if 0
+ {
+ static char *action[] = { "drop frame", "copy frame", "dup frame" };
+ printf("Input PTS %12.6f, output PTS %12.6f: %s\n",
+ (double) ost->sync_ipts, (double) ost->st->pts.val * s->pts_num / s->pts_den,
+ action[nb_frames]);
+ }
+#endif
}
}
if (nb_frames <= 0)
--
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