/*
* RTP/Quicktime support.
* Copyright (c) 2009 Ronald S. Bultje
*
* 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
*/
/**
* @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, (uint8_t*)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->codecpar->codec_type == AVMEDIA_TYPE_VIDEO &&
tag != MKTAG('v','i','d','e')) ||
(st->codecpar->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_packet_unref(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);