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authorMartin Storsjö <martin@martin.st>2010-05-18 19:47:24 +0000
committerMartin Storsjö <martin@martin.st>2010-05-18 19:47:24 +0000
commite977af6f2ea3752c8e0db04fe9a478f725cd3ebf (patch)
treed6f0ffccb5d7dac9e2ce60a96965ceeee283a481
parent27a826c941c2b0f685d97eeb21489cbd281728a7 (diff)
Add initial support for RTP hinting in the mov muxer
Originally committed as revision 23164 to svn://svn.ffmpeg.org/ffmpeg/trunk
-rw-r--r--libavformat/Makefile2
-rw-r--r--libavformat/movenc.c109
-rw-r--r--libavformat/movenc.h14
-rw-r--r--libavformat/movenchint.c292
4 files changed, 414 insertions, 3 deletions
diff --git a/libavformat/Makefile b/libavformat/Makefile
index 43a4a2e0d4..a671e283e2 100644
--- a/libavformat/Makefile
+++ b/libavformat/Makefile
@@ -114,7 +114,7 @@ OBJS-$(CONFIG_MM_DEMUXER) += mm.o
OBJS-$(CONFIG_MMF_DEMUXER) += mmf.o raw.o
OBJS-$(CONFIG_MMF_MUXER) += mmf.o riff.o
OBJS-$(CONFIG_MOV_DEMUXER) += mov.o riff.o isom.o
-OBJS-$(CONFIG_MOV_MUXER) += movenc.o riff.o isom.o avc.o
+OBJS-$(CONFIG_MOV_MUXER) += movenc.o riff.o isom.o avc.o movenchint.o
OBJS-$(CONFIG_MP2_MUXER) += mp3.o id3v1.o
OBJS-$(CONFIG_MP3_DEMUXER) += mp3.o id3v1.o id3v2.o
OBJS-$(CONFIG_MP3_MUXER) += mp3.o id3v1.o id3v2.o
diff --git a/libavformat/movenc.c b/libavformat/movenc.c
index 41a95c9f00..440c98ad26 100644
--- a/libavformat/movenc.c
+++ b/libavformat/movenc.c
@@ -29,6 +29,8 @@
#include "avc.h"
#include "libavcodec/get_bits.h"
#include "libavcodec/put_bits.h"
+#include "internal.h"
+#include "libavutil/avstring.h"
#undef NDEBUG
#include <assert.h>
@@ -806,6 +808,26 @@ static int mov_write_video_tag(ByteIOContext *pb, MOVTrack *track)
return updateSize(pb, pos);
}
+static int mov_write_rtp_tag(ByteIOContext *pb, MOVTrack *track)
+{
+ int64_t pos = url_ftell(pb);
+ put_be32(pb, 0); /* size */
+ put_tag(pb, "rtp ");
+ put_be32(pb, 0); /* Reserved */
+ put_be16(pb, 0); /* Reserved */
+ put_be16(pb, 1); /* Data-reference index */
+
+ put_be16(pb, 1); /* Hint track version */
+ put_be16(pb, 1); /* Highest compatible version */
+ put_be32(pb, track->max_packet_size); /* Max packet size */
+
+ put_be32(pb, 12); /* size */
+ put_tag(pb, "tims");
+ put_be32(pb, track->timescale);
+
+ return updateSize(pb, pos);
+}
+
static int mov_write_stsd_tag(ByteIOContext *pb, MOVTrack *track)
{
int64_t pos = url_ftell(pb);
@@ -819,6 +841,8 @@ static int mov_write_stsd_tag(ByteIOContext *pb, MOVTrack *track)
mov_write_audio_tag(pb, track);
else if (track->enc->codec_type == AVMEDIA_TYPE_SUBTITLE)
mov_write_subtitle_tag(pb, track);
+ else if (track->enc->codec_tag == MKTAG('r','t','p',' '))
+ mov_write_rtp_tag(pb, track);
return updateSize(pb, pos);
}
@@ -918,7 +942,8 @@ static int mov_write_stbl_tag(ByteIOContext *pb, MOVTrack *track)
put_tag(pb, "stbl");
mov_write_stsd_tag(pb, track);
mov_write_stts_tag(pb, track);
- if (track->enc->codec_type == AVMEDIA_TYPE_VIDEO &&
+ if ((track->enc->codec_type == AVMEDIA_TYPE_VIDEO ||
+ track->enc->codec_tag == MKTAG('r','t','p',' ')) &&
track->hasKeyframes && track->hasKeyframes < track->entry)
mov_write_stss_tag(pb, track, MOV_SYNC_SAMPLE);
if (track->mode == MODE_MOV && track->flags & MOV_TRACK_STPS)
@@ -1005,6 +1030,9 @@ static int mov_write_hdlr_tag(ByteIOContext *pb, MOVTrack *track)
if (track->tag == MKTAG('t','x','3','g')) hdlr_type = "sbtl";
else hdlr_type = "text";
descr = "SubtitleHandler";
+ } else if (track->enc->codec_tag == MKTAG('r','t','p',' ')) {
+ hdlr_type = "hint";
+ descr = "HintHandler";
}
}
@@ -1024,6 +1052,21 @@ static int mov_write_hdlr_tag(ByteIOContext *pb, MOVTrack *track)
return updateSize(pb, pos);
}
+static int mov_write_hmhd_tag(ByteIOContext *pb)
+{
+ /* This atom must be present, but leaving the values at zero
+ * seems harmless. */
+ put_be32(pb, 28); /* size */
+ put_tag(pb, "hmhd");
+ put_be32(pb, 0); /* version, flags */
+ put_be16(pb, 0); /* maxPDUsize */
+ put_be16(pb, 0); /* avgPDUsize */
+ put_be32(pb, 0); /* maxbitrate */
+ put_be32(pb, 0); /* avgbitrate */
+ put_be32(pb, 0); /* reserved */
+ return 28;
+}
+
static int mov_write_minf_tag(ByteIOContext *pb, MOVTrack *track)
{
int64_t pos = url_ftell(pb);
@@ -1036,6 +1079,8 @@ static int mov_write_minf_tag(ByteIOContext *pb, MOVTrack *track)
else if (track->enc->codec_type == AVMEDIA_TYPE_SUBTITLE) {
if (track->tag == MKTAG('t','e','x','t')) mov_write_gmhd_tag(pb);
else mov_write_nmhd_tag(pb);
+ } else if (track->tag == MKTAG('r','t','p',' ')) {
+ mov_write_hmhd_tag(pb);
}
if (track->mode == MODE_MOV) /* FIXME: Why do it for MODE_MOV only ? */
mov_write_hdlr_tag(pb, NULL);
@@ -1191,6 +1236,25 @@ static int mov_write_uuid_tag_psp(ByteIOContext *pb, MOVTrack *mov)
return 0x34;
}
+static int mov_write_udta_sdp(ByteIOContext *pb, AVCodecContext *ctx, int index)
+{
+ char buf[1000] = "";
+ int len;
+
+ ff_sdp_write_media(buf, sizeof(buf), ctx, NULL, 0, 0);
+ av_strlcatf(buf, sizeof(buf), "a=control:streamid=%d\r\n", index);
+ len = strlen(buf);
+
+ put_be32(pb, len + 24);
+ put_tag (pb, "udta");
+ put_be32(pb, len + 16);
+ put_tag (pb, "hnti");
+ put_be32(pb, len + 8);
+ put_tag (pb, "sdp ");
+ put_buffer(pb, buf, len);
+ return len + 24;
+}
+
static int mov_write_trak_tag(ByteIOContext *pb, MOVTrack *track, AVStream *st)
{
int64_t pos = url_ftell(pb);
@@ -1204,6 +1268,8 @@ static int mov_write_trak_tag(ByteIOContext *pb, MOVTrack *track, AVStream *st)
mov_write_mdia_tag(pb, track);
if (track->mode == MODE_PSP)
mov_write_uuid_tag_psp(pb,track); // PSP Movies require this uuid box
+ if (track->tag == MKTAG('r','t','p',' '))
+ mov_write_udta_sdp(pb, track->rtp_ctx->streams[0]->codec, track->trackID);
return updateSize(pb, pos);
}
@@ -1618,6 +1684,13 @@ static int mov_write_moov_tag(ByteIOContext *pb, MOVMuxContext *mov,
mov->tracks[i].tref_tag = MKTAG('c','h','a','p');
mov->tracks[i].tref_id = mov->tracks[mov->chapter_track].trackID;
}
+ for (i = 0; i < mov->nb_streams; i++) {
+ if (mov->tracks[i].tag == MKTAG('r','t','p',' ')) {
+ mov->tracks[i].tref_tag = MKTAG('h','i','n','t');
+ mov->tracks[i].tref_id =
+ mov->tracks[mov->tracks[i].src_track].trackID;
+ }
+ }
mov_write_mvhd_tag(pb, mov);
//mov_write_iods_tag(pb, mov);
@@ -1878,6 +1951,9 @@ int ff_mov_write_packet(AVFormatContext *s, AVPacket *pkt)
mov->mdat_size += size;
put_flush_packet(pb);
+
+ if (trk->hint_track >= 0 && trk->hint_track < mov->nb_streams)
+ ff_mov_add_hinted_packet(s, pkt, trk->hint_track, trk->entry);
return 0;
}
@@ -1920,7 +1996,7 @@ static int mov_write_header(AVFormatContext *s)
{
ByteIOContext *pb = s->pb;
MOVMuxContext *mov = s->priv_data;
- int i;
+ int i, hint_track = 0;
if (url_is_streamed(s->pb)) {
av_log(s, AV_LOG_ERROR, "muxer does not support non seekable output\n");
@@ -1951,6 +2027,18 @@ static int mov_write_header(AVFormatContext *s)
if (mov->mode & (MODE_MOV|MODE_IPOD) && s->nb_chapters)
mov->chapter_track = mov->nb_streams++;
+ if (s->flags & AVFMT_FLAG_RTP_HINT) {
+ /* Add hint tracks for each audio and video stream */
+ hint_track = mov->nb_streams;
+ for (i = 0; i < s->nb_streams; i++) {
+ AVStream *st = s->streams[i];
+ if (st->codec->codec_type == AVMEDIA_TYPE_VIDEO ||
+ st->codec->codec_type == AVMEDIA_TYPE_AUDIO) {
+ mov->nb_streams++;
+ }
+ }
+ }
+
mov->tracks = av_mallocz(mov->nb_streams*sizeof(*mov->tracks));
if (!mov->tracks)
return AVERROR(ENOMEM);
@@ -1971,6 +2059,9 @@ static int mov_write_header(AVFormatContext *s)
"codec not currently supported in container\n", i);
goto error;
}
+ /* If hinting of this track is enabled by a later hint track,
+ * this is updated. */
+ track->hint_track = -1;
if(st->codec->codec_type == AVMEDIA_TYPE_VIDEO){
if (track->tag == MKTAG('m','x','3','p') || track->tag == MKTAG('m','x','3','n') ||
track->tag == MKTAG('m','x','4','p') || track->tag == MKTAG('m','x','4','n') ||
@@ -2025,6 +2116,18 @@ static int mov_write_header(AVFormatContext *s)
if (mov->chapter_track)
mov_create_chapter_track(s, mov->chapter_track);
+ if (s->flags & AVFMT_FLAG_RTP_HINT) {
+ /* Initialize the hint tracks for each audio and video stream */
+ for (i = 0; i < s->nb_streams; i++) {
+ AVStream *st = s->streams[i];
+ if (st->codec->codec_type == AVMEDIA_TYPE_VIDEO ||
+ st->codec->codec_type == AVMEDIA_TYPE_AUDIO) {
+ ff_mov_init_hinting(s, hint_track, i);
+ hint_track++;
+ }
+ }
+ }
+
put_flush_packet(pb);
return 0;
@@ -2061,6 +2164,8 @@ static int mov_write_trailer(AVFormatContext *s)
av_freep(&mov->tracks[mov->chapter_track].enc);
for (i=0; i<mov->nb_streams; i++) {
+ if (mov->tracks[i].tag == MKTAG('r','t','p',' '))
+ ff_mov_close_hinting(&mov->tracks[i]);
av_freep(&mov->tracks[i].cluster);
if(mov->tracks[i].vosLen) av_free(mov->tracks[i].vosData);
diff --git a/libavformat/movenc.h b/libavformat/movenc.h
index 089701dcfe..3d8f4ba499 100644
--- a/libavformat/movenc.h
+++ b/libavformat/movenc.h
@@ -29,6 +29,8 @@
#define MOV_INDEX_CLUSTER_SIZE 16384
#define MOV_TIMESCALE 1000
+#define RTP_MAX_PACKET_SIZE 1450
+
#define MODE_MP4 0x01
#define MODE_MOV 0x02
#define MODE_3GP 0x04
@@ -73,6 +75,13 @@ typedef struct MOVIndex {
int height; ///< active picture (w/o VBI) height for D-10/IMX
uint32_t tref_tag;
int tref_id; ///< trackID of the referenced track
+
+ int hint_track; ///< the track that hints this track, -1 if no hint track is set
+ int src_track; ///< the track that this hint track describes
+ AVFormatContext *rtp_ctx; ///< the format context for the hinting rtp muxer
+ uint32_t prev_rtp_ts;
+ int64_t cur_rtp_ts_unwrapped;
+ uint32_t max_packet_size;
} MOVTrack;
typedef struct MOVMuxContext {
@@ -87,4 +96,9 @@ typedef struct MOVMuxContext {
int ff_mov_write_packet(AVFormatContext *s, AVPacket *pkt);
+int ff_mov_init_hinting(AVFormatContext *s, int index, int src_index);
+int ff_mov_add_hinted_packet(AVFormatContext *s, AVPacket *pkt,
+ int track_index, int sample);
+void ff_mov_close_hinting(MOVTrack *track);
+
#endif /* AVFORMAT_MOVENC_H */
diff --git a/libavformat/movenchint.c b/libavformat/movenchint.c
new file mode 100644
index 0000000000..e830b741a8
--- /dev/null
+++ b/libavformat/movenchint.c
@@ -0,0 +1,292 @@
+/*
+ * MOV, 3GP, MP4 muxer RTP hinting
+ * Copyright (c) 2010 Martin Storsjo
+ *
+ * This file is part of FFmpeg.
+ *
+ * FFmpeg is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation; either
+ * version 2.1 of the License, or (at your option) any later version.
+ *
+ * FFmpeg is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with FFmpeg; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
+ */
+
+#include "movenc.h"
+#include "libavutil/intreadwrite.h"
+
+int ff_mov_init_hinting(AVFormatContext *s, int index, int src_index)
+{
+ MOVMuxContext *mov = s->priv_data;
+ MOVTrack *track = &mov->tracks[index];
+ MOVTrack *src_track = &mov->tracks[src_index];
+ AVStream *src_st = s->streams[src_index];
+ int ret = AVERROR(ENOMEM);
+ AVOutputFormat *rtp_format = av_guess_format("rtp", NULL, NULL);
+
+ track->tag = MKTAG('r','t','p',' ');
+ track->src_track = src_index;
+
+ if (!rtp_format) {
+ ret = AVERROR(ENOENT);
+ goto fail;
+ }
+
+ track->enc = avcodec_alloc_context();
+ if (!track->enc)
+ goto fail;
+ track->enc->codec_type = AVMEDIA_TYPE_DATA;
+ track->enc->codec_tag = track->tag;
+
+ track->rtp_ctx = avformat_alloc_context();
+ if (!track->rtp_ctx)
+ goto fail;
+ track->rtp_ctx->oformat = rtp_format;
+ if (!av_new_stream(track->rtp_ctx, 0))
+ goto fail;
+
+ /* Copy stream parameters */
+ track->rtp_ctx->streams[0]->sample_aspect_ratio =
+ src_st->sample_aspect_ratio;
+
+ /* Remove the allocated codec context, link to the original one
+ * instead, to give the rtp muxer access to codec parameters. */
+ av_free(track->rtp_ctx->streams[0]->codec);
+ track->rtp_ctx->streams[0]->codec = src_st->codec;
+
+ if ((ret = url_open_dyn_packet_buf(&track->rtp_ctx->pb,
+ RTP_MAX_PACKET_SIZE)) < 0)
+ goto fail;
+ ret = av_write_header(track->rtp_ctx);
+ if (ret)
+ goto fail;
+
+ /* Copy the RTP AVStream timebase back to the hint AVStream */
+ track->timescale = track->rtp_ctx->streams[0]->time_base.den;
+
+ /* Mark the hinted track that packets written to it should be
+ * sent to this track for hinting. */
+ src_track->hint_track = index;
+ return 0;
+fail:
+ av_log(s, AV_LOG_WARNING,
+ "Unable to initialize hinting of stream %d\n", src_index);
+ if (track->rtp_ctx && track->rtp_ctx->pb) {
+ uint8_t *buf;
+ url_close_dyn_buf(track->rtp_ctx->pb, &buf);
+ av_free(buf);
+ }
+ if (track->rtp_ctx && track->rtp_ctx->streams[0]) {
+ av_metadata_free(&track->rtp_ctx->streams[0]->metadata);
+ av_free(track->rtp_ctx->streams[0]);
+ }
+ if (track->rtp_ctx) {
+ av_metadata_free(&track->rtp_ctx->metadata);
+ av_free(track->rtp_ctx->priv_data);
+ av_freep(&track->rtp_ctx);
+ }
+ av_freep(&track->enc);
+ /* Set a default timescale, to avoid crashes in dump_format */
+ track->timescale = 90000;
+ return ret;
+}
+
+static void output_immediate(const uint8_t *data, int size,
+ ByteIOContext *out, int *entries)
+{
+ while (size > 0) {
+ int len = size;
+ if (len > 14)
+ len = 14;
+ put_byte(out, 1); /* immediate constructor */
+ put_byte(out, len); /* amount of valid data */
+ put_buffer(out, data, len);
+ data += len;
+ size -= len;
+
+ for (; len < 14; len++)
+ put_byte(out, 0);
+
+ (*entries)++;
+ }
+}
+
+static void describe_payload(const uint8_t *data, int size,
+ ByteIOContext *out, int *entries)
+{
+ /* Describe the payload using different constructors */
+ output_immediate(data, size, out, entries);
+}
+
+/**
+ * Write an RTP hint (that may contain one or more RTP packets)
+ * for the packets in data. data contains one or more packets with a
+ * BE32 size header.
+ *
+ * @param out buffer where the hints are written
+ * @param data buffer containing RTP packets
+ * @param size the size of the data buffer
+ * @param trk the MOVTrack for the hint track
+ * @param pts pointer where the timestamp for the written RTP hint is stored
+ * @return the number of RTP packets in the written hint
+ */
+static int write_hint_packets(ByteIOContext *out, const uint8_t *data,
+ int size, MOVTrack *trk, int64_t *pts)
+{
+ int64_t curpos;
+ int64_t count_pos, entries_pos;
+ int count = 0, entries;
+
+ count_pos = url_ftell(out);
+ /* RTPsample header */
+ put_be16(out, 0); /* packet count */
+ put_be16(out, 0); /* reserved */
+
+ while (size > 4) {
+ uint32_t packet_len = AV_RB32(data);
+ uint16_t seq;
+ uint32_t ts;
+
+ data += 4;
+ size -= 4;
+ if (packet_len > size || packet_len <= 12)
+ break;
+ if (data[1] >= 200 && data[1] <= 204) {
+ /* RTCP packet, just skip */
+ data += packet_len;
+ size -= packet_len;
+ continue;
+ }
+
+ if (packet_len > trk->max_packet_size)
+ trk->max_packet_size = packet_len;
+
+ seq = AV_RB16(&data[2]);
+ ts = AV_RB32(&data[4]);
+
+ if (trk->prev_rtp_ts == 0)
+ trk->prev_rtp_ts = ts;
+ /* Unwrap the 32-bit RTP timestamp that wraps around often
+ * into a not (as often) wrapping 64-bit timestamp. */
+ trk->cur_rtp_ts_unwrapped += (int32_t) (ts - trk->prev_rtp_ts);
+ trk->prev_rtp_ts = ts;
+ if (*pts == AV_NOPTS_VALUE)
+ *pts = trk->cur_rtp_ts_unwrapped;
+
+ count++;
+ /* RTPpacket header */
+ put_be32(out, 0); /* relative_time */
+ put_buffer(out, data, 2); /* RTP header */
+ put_be16(out, seq); /* RTPsequenceseed */
+ put_be16(out, 0); /* reserved + flags */
+ entries_pos = url_ftell(out);
+ put_be16(out, 0); /* entry count */
+
+ data += 12;
+ size -= 12;
+ packet_len -= 12;
+
+ entries = 0;
+ /* Write one or more constructors describing the payload data */
+ describe_payload(data, packet_len, out, &entries);
+ data += packet_len;
+ size -= packet_len;
+
+ curpos = url_ftell(out);
+ url_fseek(out, entries_pos, SEEK_SET);
+ put_be16(out, entries);
+ url_fseek(out, curpos, SEEK_SET);
+ }
+
+ curpos = url_ftell(out);
+ url_fseek(out, count_pos, SEEK_SET);
+ put_be16(out, count);
+ url_fseek(out, curpos, SEEK_SET);
+ return count;
+}
+
+int ff_mov_add_hinted_packet(AVFormatContext *s, AVPacket *pkt,
+ int track_index, int sample)
+{
+ MOVMuxContext *mov = s->priv_data;
+ MOVTrack *trk = &mov->tracks[track_index];
+ AVFormatContext *rtp_ctx = trk->rtp_ctx;
+ uint8_t *buf = NULL;
+ int size;
+ ByteIOContext *hintbuf = NULL;
+ AVPacket hint_pkt;
+ AVPacket local_pkt;
+ int ret = 0, count;
+
+ if (!rtp_ctx)
+ return AVERROR(ENOENT);
+ if (!rtp_ctx->pb)
+ return AVERROR(ENOMEM);
+
+ /* Feed the packet to the RTP muxer */
+ local_pkt = *pkt;
+ local_pkt.stream_index = 0;
+ local_pkt.pts = av_rescale_q(pkt->pts,
+ s->streams[pkt->stream_index]->time_base,
+ rtp_ctx->streams[0]->time_base);
+ local_pkt.dts = av_rescale_q(pkt->dts,
+ s->streams[pkt->stream_index]->time_base,
+ rtp_ctx->streams[0]->time_base);
+ av_write_frame(rtp_ctx, &local_pkt);
+
+ /* Fetch the output from the RTP muxer, open a new output buffer
+ * for next time. */
+ size = url_close_dyn_buf(rtp_ctx->pb, &buf);
+ if ((ret = url_open_dyn_packet_buf(&rtp_ctx->pb,
+ RTP_MAX_PACKET_SIZE)) < 0)
+ goto done;
+
+ if (size <= 0)
+ goto done;
+
+ /* Open a buffer for writing the hint */
+ if ((ret = url_open_dyn_buf(&hintbuf)) < 0)
+ goto done;
+ av_init_packet(&hint_pkt);
+ count = write_hint_packets(hintbuf, buf, size, trk, &hint_pkt.dts);
+ av_freep(&buf);
+
+ /* Write the hint data into the hint track */
+ hint_pkt.size = size = url_close_dyn_buf(hintbuf, &buf);
+ hint_pkt.data = buf;
+ hint_pkt.pts = hint_pkt.dts;
+ hint_pkt.stream_index = track_index;
+ if (pkt->flags & AV_PKT_FLAG_KEY)
+ hint_pkt.flags |= AV_PKT_FLAG_KEY;
+ if (count > 0)
+ ff_mov_write_packet(s, &hint_pkt);
+done:
+ av_free(buf);
+ return ret;
+}
+
+void ff_mov_close_hinting(MOVTrack *track) {
+ AVFormatContext* rtp_ctx = track->rtp_ctx;
+ uint8_t *ptr;
+
+ av_freep(&track->enc);
+ if (!rtp_ctx)
+ return;
+ if (rtp_ctx->pb) {
+ av_write_trailer(rtp_ctx);
+ url_close_dyn_buf(rtp_ctx->pb, &ptr);
+ av_free(ptr);
+ }
+ av_metadata_free(&rtp_ctx->streams[0]->metadata);
+ av_metadata_free(&rtp_ctx->metadata);
+ av_free(rtp_ctx->streams[0]);
+ av_freep(&rtp_ctx);
+}
+