[FFmpeg-devel] [PATCH] replace ogg seek function by read_timestamp and generic seek
Reimar Döffinger
Reimar.Doeffinger
Wed Oct 3 15:41:27 CEST 2007
Hello,
the ogg seek function is quite complex and doesn't work that well
either, attached patch would remove it and instead add a working
read_timestamp function so we will use our generic binary search seek.
Split in two patches of course ;-)
Slightly related to issue 159.
Greetings,
Reimar D?ffinger
-------------- next part --------------
>From a39730ee91f963bb924eba29de32a473878d8d92 Mon Sep 17 00:00:00 2001
From: =?utf-8?q?Reimar=20D=C3=B6ffinger?= <reimar at hokum.(none)>
Date: Wed, 3 Oct 2007 15:35:01 +0200
Subject: [PATCH] Add a read_timestamp function to ogg demuxer
---
libavformat/ogg2.c | 25 ++++++++++++++++---------
1 files changed, 16 insertions(+), 9 deletions(-)
diff --git a/libavformat/ogg2.c b/libavformat/ogg2.c
index 2b4b160..4d73bd4 100644
--- a/libavformat/ogg2.c
+++ b/libavformat/ogg2.c
@@ -659,21 +659,28 @@ ogg_read_seek (AVFormatContext * s, int stream_index, int64_t target_ts,
}
-#if 0
static int64_t
ogg_read_timestamp (AVFormatContext * s, int stream_index, int64_t * pos_arg,
int64_t pos_limit)
{
ogg_t *ogg = s->priv_data;
ByteIOContext *bc = &s->pb;
- int64_t pos, pts;
-
- if (*pos_arg < 0)
- return AV_NOPTS_VALUE;
-
- pos = *pos_arg;
+ int64_t pts = AV_NOPTS_VALUE;
+ int i;
+ url_fseek(bc, *pos_arg, SEEK_SET);
+ while (url_ftell(bc) < pos_limit && !ogg_read_page (s, &i)) {
+ if (ogg->streams[i].granule != -1 && ogg->streams[i].granule != 0 &&
+ ogg->streams[i].codec && i == stream_index) {
+ pts = ogg_gptopts(s, i, ogg->streams[i].granule);
+ // FIXME: this is the position of the packet after the one with above
+ // pts.
+ *pos_arg = url_ftell(bc);
+ break;
+ }
+ }
+ ogg_reset(ogg);
+ return pts;
}
-#endif
static int ogg_probe(AVProbeData *p)
{
@@ -694,6 +701,6 @@ AVInputFormat ogg_demuxer = {
ogg_read_packet,
ogg_read_close,
ogg_read_seek,
-// ogg_read_timestamp,
+ ogg_read_timestamp,
.extensions = "ogg",
};
--
1.5.3.3
-------------- next part --------------
>From 3d5f37f9bec961e9ad1d76221497dfe852672ff3 Mon Sep 17 00:00:00 2001
From: =?utf-8?q?Reimar=20D=C3=B6ffinger?= <reimar at hokum.(none)>
Date: Wed, 3 Oct 2007 15:37:30 +0200
Subject: [PATCH] Remove ogg seek function, instead use generic seek via read_timestamp function
---
libavformat/ogg2.c | 85 +---------------------------------------------------
1 files changed, 1 insertions(+), 84 deletions(-)
diff --git a/libavformat/ogg2.c b/libavformat/ogg2.c
index 4d73bd4..ebc7567 100644
--- a/libavformat/ogg2.c
+++ b/libavformat/ogg2.c
@@ -576,89 +576,6 @@ ogg_read_close (AVFormatContext * s)
}
-static int
-ogg_read_seek (AVFormatContext * s, int stream_index, int64_t target_ts,
- int flags)
-{
- AVStream *st = s->streams[stream_index];
- ogg_t *ogg = s->priv_data;
- ByteIOContext *bc = &s->pb;
- uint64_t min = 0, max = ogg->size;
- uint64_t tmin = st->start_time, tmax = st->start_time + st->duration;
- int64_t pts = AV_NOPTS_VALUE;
-
- ogg_save (s);
-
- if ((uint64_t)target_ts < tmin || target_ts < 0)
- target_ts = tmin;
- while (min <= max && tmin < tmax){
- uint64_t p = min + (max - min) * (target_ts - tmin) / (tmax - tmin);
- int i = -1;
-
- url_fseek (bc, p, SEEK_SET);
-
- while (!ogg_read_page (s, &i)){
- if (i == stream_index && ogg->streams[i].granule != 0 &&
- ogg->streams[i].granule != -1)
- break;
- }
-
- if (i == -1)
- break;
-
- pts = ogg_gptopts (s, i, ogg->streams[i].granule);
- p = url_ftell (bc);
-
- if (FFABS (pts - target_ts) * st->time_base.num < st->time_base.den)
- break;
-
- if (pts > target_ts){
- if (max == p && tmax == pts) {
- // probably our tmin is wrong, causing us to always end up too late in the file
- tmin = (target_ts + tmin + 1) / 2;
- if (tmin == target_ts) {
- url_fseek(bc, min, SEEK_SET);
- break;
- }
- }
- max = p;
- tmax = pts;
- }else{
- if (min == p && tmin == pts) {
- // probably our tmax is wrong, causing us to always end up too early in the file
- tmax = (target_ts + tmax) / 2;
- if (tmax == target_ts) {
- url_fseek(bc, max, SEEK_SET);
- break;
- }
- }
- min = p;
- tmin = pts;
- }
- }
-
- if (FFABS (pts - target_ts) * st->time_base.num < st->time_base.den){
- ogg_restore (s, 1);
- ogg_reset (ogg);
- }else{
- ogg_restore (s, 0);
- pts = AV_NOPTS_VALUE;
- }
-
- av_update_cur_dts(s, st, pts);
- return 0;
-
-#if 0
- //later...
- int64_t pos;
- if (av_seek_frame_binary (s, stream_index, target_ts, flags) < 0)
- return -1;
- pos = url_ftell (&s->pb);
- ogg_read_timestamp (s, stream_index, &pos, pos - 1);
-#endif
-
-}
-
static int64_t
ogg_read_timestamp (AVFormatContext * s, int stream_index, int64_t * pos_arg,
int64_t pos_limit)
@@ -700,7 +617,7 @@ AVInputFormat ogg_demuxer = {
ogg_read_header,
ogg_read_packet,
ogg_read_close,
- ogg_read_seek,
+ NULL,
ogg_read_timestamp,
.extensions = "ogg",
};
--
1.5.3.3
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