On Thu, 26 Apr 2012, Martin Storsjö wrote:
On Thu, 26 Apr 2012, Justin Ruggles wrote:
On 04/26/2012 08:33 AM, Martin Storsjö wrote:
On Mon, 5 Mar 2012, Justin Ruggles wrote:
Module: libav
Branch: master
Commit: a7fa75684d8fd2551ef87070d9a69349beca7260
Author: Justin Ruggles <[email protected]>
Committer: Justin Ruggles <[email protected]>
Date: Mon Feb 27 18:07:07 2012 -0500
avformat: do not fill-in audio packet duration in compute_pkt_fields()
Use the estimated duration only to calculate missing timestamps if
needed.
---
libavformat/utils.c | 47
+++++++++++++++++++++++++++++++++--------------
1 files changed, 33 insertions(+), 14 deletions(-)
diff --git a/libavformat/utils.c b/libavformat/utils.c
index 7fd7c32..a1f24d4 100644
--- a/libavformat/utils.c
+++ b/libavformat/utils.c
@@ -951,12 +953,29 @@ static void compute_pkt_fields(AVFormatContext *s,
AVStream *st,
st->last_IP_pts= pkt->pts;
/* cannot compute PTS if not present (we can compute it only
by knowing the future */
- } else if(pkt->pts != AV_NOPTS_VALUE || pkt->dts !=
AV_NOPTS_VALUE || pkt->duration){
- if(pkt->pts != AV_NOPTS_VALUE && pkt->duration){
- int64_t old_diff= FFABS(st->cur_dts - pkt->duration -
pkt->pts);
+ } else if (pkt->pts != AV_NOPTS_VALUE ||
+ pkt->dts != AV_NOPTS_VALUE ||
+ pkt->duration ||
+ st->codec->codec_type == AVMEDIA_TYPE_AUDIO) {
+ int duration = pkt->duration;
+ if (!duration && st->codec->codec_type ==
AVMEDIA_TYPE_AUDIO) {
+ compute_frame_duration(&num, &den, st, pc, pkt);
+ if (den && num) {
+ duration = av_rescale_rnd(1, num *
(int64_t)st->time_base.den,
+ den *
(int64_t)st->time_base.num,
+ AV_ROUND_DOWN);
+ if (duration != 0 && s->packet_buffer) {
+ update_initial_durations(s, st,
pkt->stream_index,
+ duration);
+ }
+ }
+ }
+
+ if(pkt->pts != AV_NOPTS_VALUE && duration){
+ int64_t old_diff= FFABS(st->cur_dts - duration -
pkt->pts);
int64_t new_diff= FFABS(st->cur_dts - pkt->pts);
- if(old_diff < new_diff && old_diff <
(pkt->duration>>3)){
- pkt->pts += pkt->duration;
+ if(old_diff < new_diff && old_diff < (duration>>3)){
+ pkt->pts += duration;
// av_log(NULL, AV_LOG_DEBUG, "id:%d old:%"PRId64"
new:%"PRId64" dur:%d cur:%"PRId64" size:%d\n", pkt->stream_index,
old_diff, new_diff, pkt->duration, st->cur_dts, pkt->size);
}
}
This makes AAC in mpegts return multiple packets with the same timestamp -
earlier, only the first one had a timestamp and the later packets had
pts/dts == NOPTS.
Is this intentional or unintentional, and is there a good way to fix it?
Do you have a sample I can test? I didn't get those results when
testing a random aac-in-mpegts file.
Hmm, I only seem to get this result if I don't call avformat_find_stream_info
- if I call it, I get proper continuous timestamps for all packets.
It can be reproduced with http://albin.abo.fi/~mstorsjo/trailer.ts.
The difference caused by calling avformat_find_stream_info is that it
initializes the decoder, setting frame_size. (My use case is building a
plain demuxer without any decoders enabled.)
Perhaps the rest of the code block (below) should be enclosed in an if
statement like (!audio || duration), since your change added the condition
to always run this block for audio (since duration wasn't set but only
calculated).
if(pkt->pts == AV_NOPTS_VALUE)
pkt->pts = pkt->dts;
update_initial_timestamps(s, pkt->stream_index, pkt->pts, pkt->pts);
if(pkt->pts == AV_NOPTS_VALUE)
pkt->pts = st->cur_dts;
pkt->dts = pkt->pts;
if(pkt->pts != AV_NOPTS_VALUE)
st->cur_dts = pkt->pts + duration;
Would that make sense?
// Martin_______________________________________________
libav-devel mailing list
[email protected]
https://lists.libav.org/mailman/listinfo/libav-devel
