/* * RTP/Quicktime support. * Copyright (c) 2009 Ronald S. Bultje * * This file is part of Libav. * * Libav 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. * * Libav 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 Libav; if not, write to the Free Software * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA */ /** * @file * @brief Quicktime-style RTP support * @author Ronald S. Bultje <rbultje@ronald.bitfreak.net> */ #include "avformat.h" #include "internal.h" #include "avio_internal.h" #include "rtp.h" #include "rtpdec.h" #include "isom.h" #include "libavcodec/get_bits.h" struct PayloadContext { AVPacket pkt; int bytes_per_frame, remaining; uint32_t timestamp; }; static int qt_rtp_parse_packet(AVFormatContext *s, PayloadContext *qt, AVStream *st, AVPacket *pkt, uint32_t *timestamp, const uint8_t *buf, int len, uint16_t seq, int flags) { AVIOContext pb; GetBitContext gb; int packing_scheme, has_payload_desc, has_packet_info, alen, has_marker_bit = flags & RTP_FLAG_MARKER, keyframe; if (qt->remaining) { int num = qt->pkt.size / qt->bytes_per_frame; if (av_new_packet(pkt, qt->bytes_per_frame)) return AVERROR(ENOMEM); pkt->stream_index = st->index; pkt->flags = qt->pkt.flags; memcpy(pkt->data, &qt->pkt.data[(num - qt->remaining) * qt->bytes_per_frame], qt->bytes_per_frame); if (--qt->remaining == 0) { av_freep(&qt->pkt.data); qt->pkt.size = 0; } return qt->remaining > 0; } /** * The RTP payload is described in: * http://developer.apple.com/quicktime/icefloe/dispatch026.html */ init_get_bits(&gb, buf, len << 3); ffio_init_context(&pb, buf, len, 0, NULL, NULL, NULL, NULL); if (len < 4) return AVERROR_INVALIDDATA; skip_bits(&gb, 4); // version if ((packing_scheme = get_bits(&gb, 2)) == 0) return AVERROR_INVALIDDATA; keyframe = get_bits1(&gb); has_payload_desc = get_bits1(&gb); has_packet_info = get_bits1(&gb); skip_bits(&gb, 23); // reserved:7, cache payload info:1, payload ID:15 if (has_payload_desc) { int data_len, pos, is_start, is_finish; uint32_t tag; pos = get_bits_count(&gb) >> 3; if (pos + 12 > len) return AVERROR_INVALIDDATA; skip_bits(&gb, 2); // has non-I frames:1, is sparse:1 is_start = get_bits1(&gb); is_finish = get_bits1(&gb); if (!is_start || !is_finish) { avpriv_request_sample(s, "RTP-X-QT with payload description " "split over several packets"); return AVERROR_PATCHWELCOME; } skip_bits(&gb, 12); // reserved data_len = get_bits(&gb, 16); avio_seek(&pb, pos + 4, SEEK_SET); tag = avio_rl32(&pb); if ((st->codec->codec_type == AVMEDIA_TYPE_VIDEO && tag != MKTAG('v','i','d','e')) || (st->codec->codec_type == AVMEDIA_TYPE_AUDIO && tag != MKTAG('s','o','u','n'))) return AVERROR_INVALIDDATA; avpriv_set_pts_info(st, 32, 1, avio_rb32(&pb)); if (pos + data_len > len) return AVERROR_INVALIDDATA; /* TLVs */ while (avio_tell(&pb) + 4 < pos + data_len) { int tlv_len = avio_rb16(&pb); tag = avio_rl16(&pb); if (avio_tell(&pb) + tlv_len > pos + data_len) return AVERROR_INVALIDDATA; #define MKTAG16(a,b) MKTAG(a,b,0,0) switch (tag) { case MKTAG16('s','d'): { MOVStreamContext *msc; void *priv_data = st->priv_data; int nb_streams = s->nb_streams; MOVContext *mc = av_mallocz(sizeof(*mc)); if (!mc) return AVERROR(ENOMEM); mc->fc = s; st->priv_data = msc = av_mallocz(sizeof(MOVStreamContext)); if (!msc) { av_free(mc); st->priv_data = priv_data; return AVERROR(ENOMEM); } /* ff_mov_read_stsd_entries updates stream s->nb_streams-1, * so set it temporarily to indicate which stream to update. */ s->nb_streams = st->index + 1; ff_mov_read_stsd_entries(mc, &pb, 1); qt->bytes_per_frame = msc->bytes_per_frame; av_free(msc); av_free(mc); st->priv_data = priv_data; s->nb_streams = nb_streams; break; } default: avio_skip(&pb, tlv_len); break; } } /* 32-bit alignment */ avio_skip(&pb, ((avio_tell(&pb) + 3) & ~3) - avio_tell(&pb)); } else avio_seek(&pb, 4, SEEK_SET); if (has_packet_info) { avpriv_request_sample(s, "RTP-X-QT with packet-specific info"); return AVERROR_PATCHWELCOME; } alen = len - avio_tell(&pb); if (alen <= 0) return AVERROR_INVALIDDATA; switch (packing_scheme) { case 3: /* one data packet spread over 1 or multiple RTP packets */ if (qt->pkt.size > 0 && qt->timestamp == *timestamp) { int err; if ((err = av_reallocp(&qt->pkt.data, qt->pkt.size + alen + AV_INPUT_BUFFER_PADDING_SIZE)) < 0) { qt->pkt.size = 0; return err; } } else { av_freep(&qt->pkt.data); av_init_packet(&qt->pkt); qt->pkt.data = av_realloc(NULL, alen + AV_INPUT_BUFFER_PADDING_SIZE); if (!qt->pkt.data) return AVERROR(ENOMEM); qt->pkt.size = 0; qt->timestamp = *timestamp; } memcpy(qt->pkt.data + qt->pkt.size, buf + avio_tell(&pb), alen); qt->pkt.size += alen; if (has_marker_bit) { int ret = av_packet_from_data(pkt, qt->pkt.data, qt->pkt.size); if (ret < 0) return ret; qt->pkt.size = 0; qt->pkt.data = NULL; pkt->flags = keyframe ? AV_PKT_FLAG_KEY : 0; pkt->stream_index = st->index; memset(pkt->data + pkt->size, 0, AV_INPUT_BUFFER_PADDING_SIZE); return 0; } return AVERROR(EAGAIN); case 1: /* constant packet size, multiple packets per RTP packet */ if (qt->bytes_per_frame == 0 || alen % qt->bytes_per_frame != 0) return AVERROR_INVALIDDATA; /* wrongly padded */ qt->remaining = (alen / qt->bytes_per_frame) - 1; if (av_new_packet(pkt, qt->bytes_per_frame)) return AVERROR(ENOMEM); memcpy(pkt->data, buf + avio_tell(&pb), qt->bytes_per_frame); pkt->flags = keyframe ? AV_PKT_FLAG_KEY : 0; pkt->stream_index = st->index; if (qt->remaining > 0) { av_freep(&qt->pkt.data); qt->pkt.data = av_realloc(NULL, qt->remaining * qt->bytes_per_frame); if (!qt->pkt.data) { av_free_packet(pkt); return AVERROR(ENOMEM); } qt->pkt.size = qt->remaining * qt->bytes_per_frame; memcpy(qt->pkt.data, buf + avio_tell(&pb) + qt->bytes_per_frame, qt->remaining * qt->bytes_per_frame); qt->pkt.flags = pkt->flags; return 1; } return 0; default: /* unimplemented */ avpriv_request_sample(NULL, "RTP-X-QT with packing scheme 2"); return AVERROR_PATCHWELCOME; } } static void qt_rtp_close(PayloadContext *qt) { av_freep(&qt->pkt.data); } #define RTP_QT_HANDLER(m, n, s, t) \ RTPDynamicProtocolHandler ff_ ## m ## _rtp_ ## n ## _handler = { \ .enc_name = s, \ .codec_type = t, \ .codec_id = AV_CODEC_ID_NONE, \ .priv_data_size = sizeof(PayloadContext), \ .close = qt_rtp_close, \ .parse_packet = qt_rtp_parse_packet, \ } RTP_QT_HANDLER(qt, vid, "X-QT", AVMEDIA_TYPE_VIDEO); RTP_QT_HANDLER(qt, aud, "X-QT", AVMEDIA_TYPE_AUDIO); RTP_QT_HANDLER(quicktime, vid, "X-QUICKTIME", AVMEDIA_TYPE_VIDEO); RTP_QT_HANDLER(quicktime, aud, "X-QUICKTIME", AVMEDIA_TYPE_AUDIO);