0,0 → 1,307 |
/* |
* Microsoft RTP/ASF support. |
* Copyright (c) 2008 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 Microsoft RTP/ASF support |
* @author Ronald S. Bultje <rbultje@ronald.bitfreak.net> |
*/ |
|
#include "libavutil/base64.h" |
#include "libavutil/avstring.h" |
#include "libavutil/intreadwrite.h" |
#include "rtp.h" |
#include "rtpdec_formats.h" |
#include "rtsp.h" |
#include "asf.h" |
#include "avio_internal.h" |
#include "internal.h" |
|
/** |
* From MSDN 2.2.1.4, we learn that ASF data packets over RTP should not |
* contain any padding. Unfortunately, the header min/max_pktsize are not |
* updated (thus making min_pktsize invalid). Here, we "fix" these faulty |
* min_pktsize values in the ASF file header. |
* @return 0 on success, <0 on failure (currently -1). |
*/ |
static int rtp_asf_fix_header(uint8_t *buf, int len) |
{ |
uint8_t *p = buf, *end = buf + len; |
|
if (len < sizeof(ff_asf_guid) * 2 + 22 || |
memcmp(p, ff_asf_header, sizeof(ff_asf_guid))) { |
return -1; |
} |
p += sizeof(ff_asf_guid) + 14; |
do { |
uint64_t chunksize = AV_RL64(p + sizeof(ff_asf_guid)); |
if (memcmp(p, ff_asf_file_header, sizeof(ff_asf_guid))) { |
if (chunksize > end - p) |
return -1; |
p += chunksize; |
continue; |
} |
|
/* skip most of the file header, to min_pktsize */ |
p += 6 * 8 + 3 * 4 + sizeof(ff_asf_guid) * 2; |
if (p + 8 <= end && AV_RL32(p) == AV_RL32(p + 4)) { |
/* and set that to zero */ |
AV_WL32(p, 0); |
return 0; |
} |
break; |
} while (end - p >= sizeof(ff_asf_guid) + 8); |
|
return -1; |
} |
|
/** |
* The following code is basically a buffered AVIOContext, |
* with the added benefit of returning -EAGAIN (instead of 0) |
* on packet boundaries, such that the ASF demuxer can return |
* safely and resume business at the next packet. |
*/ |
static int packetizer_read(void *opaque, uint8_t *buf, int buf_size) |
{ |
return AVERROR(EAGAIN); |
} |
|
static void init_packetizer(AVIOContext *pb, uint8_t *buf, int len) |
{ |
ffio_init_context(pb, buf, len, 0, NULL, packetizer_read, NULL, NULL); |
|
/* this "fills" the buffer with its current content */ |
pb->pos = len; |
pb->buf_end = buf + len; |
} |
|
int ff_wms_parse_sdp_a_line(AVFormatContext *s, const char *p) |
{ |
int ret = 0; |
if (av_strstart(p, "pgmpu:data:application/vnd.ms.wms-hdr.asfv1;base64,", &p)) { |
AVIOContext pb; |
RTSPState *rt = s->priv_data; |
AVDictionary *opts = NULL; |
int len = strlen(p) * 6 / 8; |
char *buf = av_mallocz(len); |
av_base64_decode(buf, p, len); |
|
if (rtp_asf_fix_header(buf, len) < 0) |
av_log(s, AV_LOG_ERROR, |
"Failed to fix invalid RTSP-MS/ASF min_pktsize\n"); |
init_packetizer(&pb, buf, len); |
if (rt->asf_ctx) { |
avformat_close_input(&rt->asf_ctx); |
} |
if (!(rt->asf_ctx = avformat_alloc_context())) |
return AVERROR(ENOMEM); |
rt->asf_ctx->pb = &pb; |
av_dict_set(&opts, "no_resync_search", "1", 0); |
ret = avformat_open_input(&rt->asf_ctx, "", &ff_asf_demuxer, &opts); |
av_dict_free(&opts); |
if (ret < 0) |
return ret; |
av_dict_copy(&s->metadata, rt->asf_ctx->metadata, 0); |
rt->asf_pb_pos = avio_tell(&pb); |
av_free(buf); |
rt->asf_ctx->pb = NULL; |
} |
return ret; |
} |
|
static int asfrtp_parse_sdp_line(AVFormatContext *s, int stream_index, |
PayloadContext *asf, const char *line) |
{ |
if (stream_index < 0) |
return 0; |
if (av_strstart(line, "stream:", &line)) { |
RTSPState *rt = s->priv_data; |
|
s->streams[stream_index]->id = strtol(line, NULL, 10); |
|
if (rt->asf_ctx) { |
int i; |
|
for (i = 0; i < rt->asf_ctx->nb_streams; i++) { |
if (s->streams[stream_index]->id == rt->asf_ctx->streams[i]->id) { |
*s->streams[stream_index]->codec = |
*rt->asf_ctx->streams[i]->codec; |
rt->asf_ctx->streams[i]->codec->extradata_size = 0; |
rt->asf_ctx->streams[i]->codec->extradata = NULL; |
avpriv_set_pts_info(s->streams[stream_index], 32, 1, 1000); |
} |
} |
} |
} |
|
return 0; |
} |
|
struct PayloadContext { |
AVIOContext *pktbuf, pb; |
uint8_t *buf; |
}; |
|
/** |
* @return 0 when a packet was written into /p pkt, and no more data is left; |
* 1 when a packet was written into /p pkt, and more packets might be left; |
* <0 when not enough data was provided to return a full packet, or on error. |
*/ |
static int asfrtp_parse_packet(AVFormatContext *s, PayloadContext *asf, |
AVStream *st, AVPacket *pkt, |
uint32_t *timestamp, |
const uint8_t *buf, int len, uint16_t seq, |
int flags) |
{ |
AVIOContext *pb = &asf->pb; |
int res, mflags, len_off; |
RTSPState *rt = s->priv_data; |
|
if (!rt->asf_ctx) |
return -1; |
|
if (len > 0) { |
int off, out_len = 0; |
|
if (len < 4) |
return -1; |
|
av_freep(&asf->buf); |
|
ffio_init_context(pb, buf, len, 0, NULL, NULL, NULL, NULL); |
|
while (avio_tell(pb) + 4 < len) { |
int start_off = avio_tell(pb); |
|
mflags = avio_r8(pb); |
if (mflags & 0x80) |
flags |= RTP_FLAG_KEY; |
len_off = avio_rb24(pb); |
if (mflags & 0x20) /**< relative timestamp */ |
avio_skip(pb, 4); |
if (mflags & 0x10) /**< has duration */ |
avio_skip(pb, 4); |
if (mflags & 0x8) /**< has location ID */ |
avio_skip(pb, 4); |
off = avio_tell(pb); |
|
if (!(mflags & 0x40)) { |
/** |
* If 0x40 is not set, the len_off field specifies an offset |
* of this packet's payload data in the complete (reassembled) |
* ASF packet. This is used to spread one ASF packet over |
* multiple RTP packets. |
*/ |
if (asf->pktbuf && len_off != avio_tell(asf->pktbuf)) { |
uint8_t *p; |
avio_close_dyn_buf(asf->pktbuf, &p); |
asf->pktbuf = NULL; |
av_free(p); |
} |
if (!len_off && !asf->pktbuf && |
(res = avio_open_dyn_buf(&asf->pktbuf)) < 0) |
return res; |
if (!asf->pktbuf) |
return AVERROR(EIO); |
|
avio_write(asf->pktbuf, buf + off, len - off); |
avio_skip(pb, len - off); |
if (!(flags & RTP_FLAG_MARKER)) |
return -1; |
out_len = avio_close_dyn_buf(asf->pktbuf, &asf->buf); |
asf->pktbuf = NULL; |
} else { |
/** |
* If 0x40 is set, the len_off field specifies the length of |
* the next ASF packet that can be read from this payload |
* data alone. This is commonly the same as the payload size, |
* but could be less in case of packet splitting (i.e. |
* multiple ASF packets in one RTP packet). |
*/ |
|
int cur_len = start_off + len_off - off; |
int prev_len = out_len; |
out_len += cur_len; |
if (FFMIN(cur_len, len - off) < 0) |
return -1; |
if ((res = av_reallocp(&asf->buf, out_len)) < 0) |
return res; |
memcpy(asf->buf + prev_len, buf + off, |
FFMIN(cur_len, len - off)); |
avio_skip(pb, cur_len); |
} |
} |
|
init_packetizer(pb, asf->buf, out_len); |
pb->pos += rt->asf_pb_pos; |
pb->eof_reached = 0; |
rt->asf_ctx->pb = pb; |
} |
|
for (;;) { |
int i; |
|
res = ff_read_packet(rt->asf_ctx, pkt); |
rt->asf_pb_pos = avio_tell(pb); |
if (res != 0) |
break; |
for (i = 0; i < s->nb_streams; i++) { |
if (s->streams[i]->id == rt->asf_ctx->streams[pkt->stream_index]->id) { |
pkt->stream_index = i; |
return 1; // FIXME: return 0 if last packet |
} |
} |
av_free_packet(pkt); |
} |
|
return res == 1 ? -1 : res; |
} |
|
static PayloadContext *asfrtp_new_context(void) |
{ |
return av_mallocz(sizeof(PayloadContext)); |
} |
|
static void asfrtp_free_context(PayloadContext *asf) |
{ |
if (asf->pktbuf) { |
uint8_t *p = NULL; |
avio_close_dyn_buf(asf->pktbuf, &p); |
asf->pktbuf = NULL; |
av_free(p); |
} |
av_freep(&asf->buf); |
av_free(asf); |
} |
|
#define RTP_ASF_HANDLER(n, s, t) \ |
RTPDynamicProtocolHandler ff_ms_rtp_ ## n ## _handler = { \ |
.enc_name = s, \ |
.codec_type = t, \ |
.codec_id = AV_CODEC_ID_NONE, \ |
.parse_sdp_a_line = asfrtp_parse_sdp_line, \ |
.alloc = asfrtp_new_context, \ |
.free = asfrtp_free_context, \ |
.parse_packet = asfrtp_parse_packet, \ |
} |
|
RTP_ASF_HANDLER(asf_pfv, "x-asf-pf", AVMEDIA_TYPE_VIDEO); |
RTP_ASF_HANDLER(asf_pfa, "x-asf-pf", AVMEDIA_TYPE_AUDIO); |