FFmpeg
rtpdec_mpegts.c
Go to the documentation of this file.
1 /*
2  * RTP MPEG2TS depacketizer
3  * Copyright (c) 2003 Fabrice Bellard
4  *
5  * This file is part of FFmpeg.
6  *
7  * FFmpeg is free software; you can redistribute it and/or
8  * modify it under the terms of the GNU Lesser General Public
9  * License as published by the Free Software Foundation; either
10  * version 2.1 of the License, or (at your option) any later version.
11  *
12  * FFmpeg is distributed in the hope that it will be useful,
13  * but WITHOUT ANY WARRANTY; without even the implied warranty of
14  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
15  * Lesser General Public License for more details.
16  *
17  * You should have received a copy of the GNU Lesser General Public
18  * License along with FFmpeg; if not, write to the Free Software
19  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
20  */
21 
22 #include "libavutil/attributes.h"
23 #include "mpegts.h"
24 #include "rtpdec_formats.h"
25 
26 struct PayloadContext {
27  struct MpegTSContext *ts;
31 };
32 
34 {
35  if (!data)
36  return;
37  if (data->ts)
39 }
40 
41 static av_cold int mpegts_init(AVFormatContext *ctx, int st_index,
43 {
44  data->ts = avpriv_mpegts_parse_open(ctx);
45  if (!data->ts)
46  return AVERROR(ENOMEM);
47  return 0;
48 }
49 
51  AVStream *st, AVPacket *pkt, uint32_t *timestamp,
52  const uint8_t *buf, int len, uint16_t seq,
53  int flags)
54 {
55  int ret;
56 
57  // We don't want to use the RTP timestamps at all. If the mpegts demuxer
58  // doesn't set any pts/dts, the generic rtpdec code shouldn't try to
59  // fill it in either, since the mpegts and RTP timestamps are in totally
60  // different ranges.
61  *timestamp = RTP_NOTS_VALUE;
62 
63  if (!buf) {
64  if (data->read_buf_index >= data->read_buf_size)
65  return AVERROR(EAGAIN);
66  ret = avpriv_mpegts_parse_packet(data->ts, pkt, data->buf + data->read_buf_index,
67  data->read_buf_size - data->read_buf_index);
68  if (ret < 0)
69  return AVERROR(EAGAIN);
70  data->read_buf_index += ret;
71  if (data->read_buf_index < data->read_buf_size)
72  return 1;
73  else
74  return 0;
75  }
76 
77  ret = avpriv_mpegts_parse_packet(data->ts, pkt, buf, len);
78  /* The only error that can be returned from avpriv_mpegts_parse_packet
79  * is "no more data to return from the provided buffer", so return
80  * AVERROR(EAGAIN) for all errors */
81  if (ret < 0)
82  return AVERROR(EAGAIN);
83  if (ret < len) {
84  data->read_buf_size = FFMIN(len - ret, sizeof(data->buf));
85  memcpy(data->buf, buf + ret, data->read_buf_size);
86  data->read_buf_index = 0;
87  return 1;
88  }
89  return 0;
90 }
91 
94  .priv_data_size = sizeof(PayloadContext),
96  .init = mpegts_init,
97  .close = mpegts_close_context,
98  .static_payload_id = 33,
99 };
AVPacket pkt
Definition: rtpdec_qt.c:37
#define RTP_MAX_PACKET_LENGTH
Definition: rtpdec.h:36
ptrdiff_t const GLvoid * data
Definition: opengl_enc.c:100
static int mpegts_handle_packet(AVFormatContext *ctx, PayloadContext *data, AVStream *st, AVPacket *pkt, uint32_t *timestamp, const uint8_t *buf, int len, uint16_t seq, int flags)
Definition: rtpdec_mpegts.c:50
struct MpegTSContext * ts
Definition: rtpdec_mpegts.c:27
const RTPDynamicProtocolHandler ff_mpegts_dynamic_handler
Definition: rtpdec_mpegts.c:92
static av_cold int init(AVCodecContext *avctx)
Definition: avrndec.c:35
static int parse_packet(AVFormatContext *s, AVPacket *pkt, int stream_index, int flush)
Parse a packet, add all split parts to parse_queue.
Definition: utils.c:1447
RTP/JPEG specific private data.
Definition: rdt.c:83
MpegTSContext * avpriv_mpegts_parse_open(AVFormatContext *s)
Definition: mpegts.c:3289
enum AVMediaType codec_type
Definition: rtpdec.h:117
Macro definitions for various function/variable attributes.
Format I/O context.
Definition: avformat.h:1358
uint8_t
#define av_cold
Definition: attributes.h:82
Opaque data information usually continuous.
Definition: avutil.h:203
uint32_t timestamp
current frame timestamp
Definition: rtpdec_ac3.c:31
#define FFMIN(a, b)
Definition: common.h:96
AVFormatContext * ctx
Definition: movenc.c:48
Stream structure.
Definition: avformat.h:881
static av_cold int mpegts_init(AVFormatContext *ctx, int st_index, PayloadContext *data)
Definition: rtpdec_mpegts.c:41
uint8_t * buf
the temporary storage buffer
Definition: rtpdec_asf.c:183
int avpriv_mpegts_parse_packet(MpegTSContext *ts, AVPacket *pkt, const uint8_t *buf, int len)
Definition: mpegts.c:3310
#define flags(name, subs,...)
Definition: cbs_av1.c:561
static void mpegts_close_context(PayloadContext *data)
Definition: rtpdec_mpegts.c:33
#define RTP_NOTS_VALUE
Definition: rtpdec.h:40
Filter the word “frame” indicates either a video frame or a group of audio as stored in an AVFrame structure Format for each input and each output the list of supported formats For video that means pixel format For audio that means channel sample they are references to shared objects When the negotiation mechanism computes the intersection of the formats supported at each end of a all references to both lists are replaced with a reference to the intersection And when a single format is eventually chosen for a link amongst the remaining all references to the list are updated That means that if a filter requires that its input and output have the same format amongst a supported all it has to do is use a reference to the same list of formats query_formats can leave some formats unset and return AVERROR(EAGAIN) to cause the negotiation mechanism toagain later.That can be used by filters with complex requirements to use the format negotiated on one link to set the formats supported on another.Frame references ownership and permissions
void avpriv_mpegts_parse_close(MpegTSContext *ts)
Definition: mpegts.c:3335
This structure stores compressed data.
Definition: avcodec.h:1457