| 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; |
| 28 | int read_buf_index; |
| 29 | int read_buf_size; |
| 30 | uint8_t buf[RTP_MAX_PACKET_LENGTH]; |
| 31 | }; |
| 32 | |
| 33 | static PayloadContext *mpegts_new_context(void) |
| 34 | { |
| 35 | return av_mallocz(sizeof(PayloadContext)); |
| 36 | } |
| 37 | |
| 38 | static void mpegts_free_context(PayloadContext *data) |
| 39 | { |
| 40 | if (!data) |
| 41 | return; |
| 42 | if (data->ts) |
| 43 | avpriv_mpegts_parse_close(data->ts); |
| 44 | av_free(data); |
| 45 | } |
| 46 | |
| 47 | static av_cold int mpegts_init(AVFormatContext *ctx, int st_index, |
| 48 | PayloadContext *data) |
| 49 | { |
| 50 | data->ts = avpriv_mpegts_parse_open(ctx); |
| 51 | if (!data->ts) |
| 52 | return AVERROR(ENOMEM); |
| 53 | return 0; |
| 54 | } |
| 55 | |
| 56 | static int mpegts_handle_packet(AVFormatContext *ctx, PayloadContext *data, |
| 57 | AVStream *st, AVPacket *pkt, uint32_t *timestamp, |
| 58 | const uint8_t *buf, int len, uint16_t seq, |
| 59 | int flags) |
| 60 | { |
| 61 | int ret; |
| 62 | |
| 63 | // We don't want to use the RTP timestamps at all. If the mpegts demuxer |
| 64 | // doesn't set any pts/dts, the generic rtpdec code shouldn't try to |
| 65 | // fill it in either, since the mpegts and RTP timestamps are in totally |
| 66 | // different ranges. |
| 67 | *timestamp = RTP_NOTS_VALUE; |
| 68 | |
| 69 | if (!data->ts) |
| 70 | return AVERROR(EINVAL); |
| 71 | |
| 72 | if (!buf) { |
| 73 | if (data->read_buf_index >= data->read_buf_size) |
| 74 | return AVERROR(EAGAIN); |
| 75 | ret = avpriv_mpegts_parse_packet(data->ts, pkt, data->buf + data->read_buf_index, |
| 76 | data->read_buf_size - data->read_buf_index); |
| 77 | if (ret < 0) |
| 78 | return AVERROR(EAGAIN); |
| 79 | data->read_buf_index += ret; |
| 80 | if (data->read_buf_index < data->read_buf_size) |
| 81 | return 1; |
| 82 | else |
| 83 | return 0; |
| 84 | } |
| 85 | |
| 86 | ret = avpriv_mpegts_parse_packet(data->ts, pkt, buf, len); |
| 87 | /* The only error that can be returned from avpriv_mpegts_parse_packet |
| 88 | * is "no more data to return from the provided buffer", so return |
| 89 | * AVERROR(EAGAIN) for all errors */ |
| 90 | if (ret < 0) |
| 91 | return AVERROR(EAGAIN); |
| 92 | if (ret < len) { |
| 93 | data->read_buf_size = FFMIN(len - ret, sizeof(data->buf)); |
| 94 | memcpy(data->buf, buf + ret, data->read_buf_size); |
| 95 | data->read_buf_index = 0; |
| 96 | return 1; |
| 97 | } |
| 98 | return 0; |
| 99 | } |
| 100 | |
| 101 | RTPDynamicProtocolHandler ff_mpegts_dynamic_handler = { |
| 102 | .codec_type = AVMEDIA_TYPE_DATA, |
| 103 | .parse_packet = mpegts_handle_packet, |
| 104 | .alloc = mpegts_new_context, |
| 105 | .init = mpegts_init, |
| 106 | .free = mpegts_free_context, |
| 107 | .static_payload_id = 33, |
| 108 | }; |