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1 e9dea59f Ronald S. Bultje
/*
2
 * Realmedia RTSP protocol (RDT) support.
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 * Copyright (c) 2007 Ronald S. Bultje
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 *
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 * This file is part of FFmpeg.
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 *
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 * FFmpeg is free software; you can redistribute it and/or
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 * 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.
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 *
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 * FFmpeg is distributed in the hope that it will be useful,
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 * but WITHOUT ANY WARRANTY; without even the implied warranty of
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 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
15
 * Lesser General Public License for more details.
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 *
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 * You should have received a copy of the GNU Lesser General Public
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 * License along with FFmpeg; if not, write to the Free Software
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 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
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 */
21
22
/**
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 * @file
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 * @brief Realmedia RTSP protocol (RDT) support
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 * @author Ronald S. Bultje <rbultje@ronald.bitfreak.net>
26
 */
27
28
#include "avformat.h"
29
#include "libavutil/avstring.h"
30 302879cb Luca Abeni
#include "rtpdec.h"
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#include "rdt.h"
32
#include "libavutil/base64.h"
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#include "libavutil/md5.h"
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#include "rm.h"
35
#include "internal.h"
36 9106a698 Stefano Sabatini
#include "libavcodec/get_bits.h"
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struct RDTDemuxContext {
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    AVFormatContext *ic; /**< the containing (RTSP) demux context */
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    /** Each RDT stream-set (represented by one RTSPStream) can contain
41
     * multiple streams (of the same content, but with possibly different
42
     * codecs/bitrates). Each such stream is represented by one AVStream
43
     * in the AVFormatContext, and this variable points to the offset in
44
     * that array such that the first is the first stream of this set. */
45
    AVStream **streams;
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    int n_streams; /**< streams with identifical content in this set */
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    void *dynamic_protocol_context;
48
    DynamicPayloadPacketHandlerProc parse_packet;
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    uint32_t prev_timestamp;
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    int prev_set_id, prev_stream_id;
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};
52
53
RDTDemuxContext *
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ff_rdt_parse_open(AVFormatContext *ic, int first_stream_of_set_idx,
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                  void *priv_data, RTPDynamicProtocolHandler *handler)
56
{
57
    RDTDemuxContext *s = av_mallocz(sizeof(RDTDemuxContext));
58
    if (!s)
59
        return NULL;
60
61
    s->ic = ic;
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    s->streams = &ic->streams[first_stream_of_set_idx];
63
    do {
64
        s->n_streams++;
65
    } while (first_stream_of_set_idx + s->n_streams < ic->nb_streams &&
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             s->streams[s->n_streams]->id == s->streams[0]->id);
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    s->prev_set_id    = -1;
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    s->prev_stream_id = -1;
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    s->prev_timestamp = -1;
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    s->parse_packet = handler ? handler->parse_packet : NULL;
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    s->dynamic_protocol_context = priv_data;
72
73
    return s;
74
}
75
76
void
77
ff_rdt_parse_close(RDTDemuxContext *s)
78
{
79
    av_free(s);
80
}
81
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struct PayloadContext {
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    AVFormatContext *rmctx;
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    int nb_rmst;
85
    RMStream **rmst;
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    uint8_t *mlti_data;
87
    unsigned int mlti_data_size;
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    char buffer[RTP_MAX_PACKET_LENGTH + FF_INPUT_BUFFER_PADDING_SIZE];
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    int audio_pkt_cnt; /**< remaining audio packets in rmdec */
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};
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void
93
ff_rdt_calc_response_and_checksum(char response[41], char chksum[9],
94
                                  const char *challenge)
95
{
96
    int ch_len = strlen (challenge), i;
97
    unsigned char zres[16],
98
        buf[64] = { 0xa1, 0xe9, 0x14, 0x9d, 0x0e, 0x6b, 0x3b, 0x59 };
99
#define XOR_TABLE_SIZE 37
100
    const unsigned char xor_table[XOR_TABLE_SIZE] = {
101
        0x05, 0x18, 0x74, 0xd0, 0x0d, 0x09, 0x02, 0x53,
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        0xc0, 0x01, 0x05, 0x05, 0x67, 0x03, 0x19, 0x70,
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        0x08, 0x27, 0x66, 0x10, 0x10, 0x72, 0x08, 0x09,
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        0x63, 0x11, 0x03, 0x71, 0x08, 0x08, 0x70, 0x02,
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        0x10, 0x57, 0x05, 0x18, 0x54 };
106
107
    /* some (length) checks */
108
    if (ch_len == 40) /* what a hack... */
109
        ch_len = 32;
110
    else if (ch_len > 56)
111
        ch_len = 56;
112
    memcpy(buf + 8, challenge, ch_len);
113
114
    /* xor challenge bytewise with xor_table */
115
    for (i = 0; i < XOR_TABLE_SIZE; i++)
116
        buf[8 + i] ^= xor_table[i];
117
118
    av_md5_sum(zres, buf, 64);
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    ff_data_to_hex(response, zres, 16, 1);
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121
    /* add tail */
122
    strcpy (response + 32, "01d0a8e3");
123
124
    /* calculate checksum */
125
    for (i = 0; i < 8; i++)
126
        chksum[i] = response[i * 4];
127
    chksum[8] = 0;
128
}
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130
static int
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rdt_load_mdpr (PayloadContext *rdt, AVStream *st, int rule_nr)
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{
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    ByteIOContext pb;
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    int size;
135
    uint32_t tag;
136
137
    /**
138
     * Layout of the MLTI chunk:
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     * 4: MLTI
140
     * 2: number of streams
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     * Then for each stream ([number_of_streams] times):
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     *     2: mdpr index
143
     * 2: number of mdpr chunks
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     * Then for each mdpr chunk ([number_of_mdpr_chunks] times):
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     *     4: size
146
     *     [size]: data
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     * we skip MDPR chunks until we reach the one of the stream
148
     * we're interested in, and forward that ([size]+[data]) to
149
     * the RM demuxer to parse the stream-specific header data.
150
     */
151
    if (!rdt->mlti_data)
152
        return -1;
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    init_put_byte(&pb, rdt->mlti_data, rdt->mlti_data_size, 0,
154
                  NULL, NULL, NULL, NULL);
155
    tag = get_le32(&pb);
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    if (tag == MKTAG('M', 'L', 'T', 'I')) {
157
        int num, chunk_nr;
158
159
        /* read index of MDPR chunk numbers */
160 a4b8cb3c Ronald S. Bultje
        num = get_be16(&pb);
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        if (rule_nr < 0 || rule_nr >= num)
162
            return -1;
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        url_fskip(&pb, rule_nr * 2);
164
        chunk_nr = get_be16(&pb);
165
        url_fskip(&pb, (num - 1 - rule_nr) * 2);
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167
        /* read MDPR chunks */
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        num = get_be16(&pb);
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        if (chunk_nr >= num)
170
            return -1;
171
        while (chunk_nr--)
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            url_fskip(&pb, get_be32(&pb));
173
        size = get_be32(&pb);
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    } else {
175
        size = rdt->mlti_data_size;
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        url_fseek(&pb, 0, SEEK_SET);
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    }
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    if (ff_rm_read_mdpr_codecdata(rdt->rmctx, &pb, st, rdt->rmst[st->index], size) < 0)
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        return -1;
180
181
    return 0;
182
}
183
184 4fce284c Ronald S. Bultje
/**
185
 * Actual data handling.
186
 */
187
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int
189
ff_rdt_parse_header(const uint8_t *buf, int len,
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                    int *pset_id, int *pseq_no, int *pstream_id,
191
                    int *pis_keyframe, uint32_t *ptimestamp)
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{
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    GetBitContext gb;
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    int consumed = 0, set_id, seq_no, stream_id, is_keyframe,
195
        len_included, need_reliable;
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    uint32_t timestamp;
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    /* skip status packets */
199
    while (len >= 5 && buf[1] == 0xFF /* status packet */) {
200
        int pkt_len;
201
202
        if (!(buf[0] & 0x80))
203
            return -1; /* not followed by a data packet */
204
205
        pkt_len = AV_RB16(buf+3);
206
        buf += pkt_len;
207
        len -= pkt_len;
208
        consumed += pkt_len;
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    }
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    if (len < 16)
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        return -1;
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    /**
213
     * Layout of the header (in bits):
214
     * 1:  len_included
215
     *     Flag indicating whether this header includes a length field;
216
     *     this can be used to concatenate multiple RDT packets in a
217
     *     single UDP/TCP data frame and is used to precede RDT data
218
     *     by stream status packets
219
     * 1:  need_reliable
220
     *     Flag indicating whether this header includes a "reliable
221
     *     sequence number"; these are apparently sequence numbers of
222
     *     data packets alone. For data packets, this flag is always
223
     *     set, according to the Real documentation [1]
224
     * 5:  set_id
225
     *     ID of a set of streams of identical content, possibly with
226
     *     different codecs or bitrates
227
     * 1:  is_reliable
228
     *     Flag set for certain streams deemed less tolerable for packet
229
     *     loss
230
     * 16: seq_no
231
     *     Packet sequence number; if >=0xFF00, this is a non-data packet
232
     *     containing stream status info, the second byte indicates the
233
     *     type of status packet (see wireshark docs / source code [2])
234
     * if (len_included) {
235
     *     16: packet_len
236
     * } else {
237
     *     packet_len = remainder of UDP/TCP frame
238
     * }
239
     * 1:  is_back_to_back
240
     *     Back-to-Back flag; used for timing, set for one in every 10
241
     *     packets, according to the Real documentation [1]
242
     * 1:  is_slow_data
243
     *     Slow-data flag; currently unused, according to Real docs [1]
244
     * 5:  stream_id
245
     *     ID of the stream within this particular set of streams
246
     * 1:  is_no_keyframe
247
     *     Non-keyframe flag (unset if packet belongs to a keyframe)
248
     * 32: timestamp (PTS)
249
     * if (set_id == 0x1F) {
250
     *     16: set_id (extended set-of-streams ID; see set_id)
251
     * }
252
     * if (need_reliable) {
253
     *     16: reliable_seq_no
254
     *         Reliable sequence number (see need_reliable)
255
     * }
256
     * if (stream_id == 0x3F) {
257
     *     16: stream_id (extended stream ID; see stream_id)
258
     * }
259
     * [1] https://protocol.helixcommunity.org/files/2005/devdocs/RDT_Feature_Level_20.txt
260
     * [2] http://www.wireshark.org/docs/dfref/r/rdt.html and
261
     *     http://anonsvn.wireshark.org/viewvc/trunk/epan/dissectors/packet-rdt.c
262
     */
263 6bafd6f5 Ronald S. Bultje
    init_get_bits(&gb, buf, len << 3);
264 43af8b2b Ronald S. Bultje
    len_included  = get_bits1(&gb);
265
    need_reliable = get_bits1(&gb);
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    set_id        = get_bits(&gb, 5);
267
    skip_bits(&gb, 1);
268
    seq_no        = get_bits(&gb, 16);
269 43af8b2b Ronald S. Bultje
    if (len_included)
270
        skip_bits(&gb, 16);
271 6bafd6f5 Ronald S. Bultje
    skip_bits(&gb, 2);
272
    stream_id     = get_bits(&gb, 5);
273
    is_keyframe   = !get_bits1(&gb);
274
    timestamp     = get_bits_long(&gb, 32);
275 43af8b2b Ronald S. Bultje
    if (set_id == 0x1f)
276
        set_id    = get_bits(&gb, 16);
277
    if (need_reliable)
278 90e0450f Ronald S. Bultje
        skip_bits(&gb, 16);
279 43af8b2b Ronald S. Bultje
    if (stream_id == 0x1f)
280
        stream_id = get_bits(&gb, 16);
281 4fce284c Ronald S. Bultje
282 6bafd6f5 Ronald S. Bultje
    if (pset_id)      *pset_id      = set_id;
283
    if (pseq_no)      *pseq_no      = seq_no;
284
    if (pstream_id)   *pstream_id   = stream_id;
285
    if (pis_keyframe) *pis_keyframe = is_keyframe;
286
    if (ptimestamp)   *ptimestamp   = timestamp;
287
288
    return consumed + (get_bits_count(&gb) >> 3);
289 4fce284c Ronald S. Bultje
}
290
291
/**< return 0 on packet, no more left, 1 on packet, 1 on partial packet... */
292
static int
293 1a45a9f4 Ronald S. Bultje
rdt_parse_packet (AVFormatContext *ctx, PayloadContext *rdt, AVStream *st,
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                  AVPacket *pkt, uint32_t *timestamp,
295 4fce284c Ronald S. Bultje
                  const uint8_t *buf, int len, int flags)
296
{
297
    int seq = 1, res;
298 a4b8cb3c Ronald S. Bultje
    ByteIOContext pb;
299 4fce284c Ronald S. Bultje
300 a15ebf34 Ronald S. Bultje
    if (rdt->audio_pkt_cnt == 0) {
301 4fce284c Ronald S. Bultje
        int pos;
302
303 a4b8cb3c Ronald S. Bultje
        init_put_byte(&pb, buf, len, 0, NULL, NULL, NULL, NULL);
304 a68d44ed Ronald S. Bultje
        flags = (flags & RTP_FLAG_KEY) ? 2 : 0;
305 7c68a177 Ronald S. Bultje
        res = ff_rm_parse_packet (rdt->rmctx, &pb, st, rdt->rmst[st->index], len, pkt,
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                                  &seq, flags, *timestamp);
307 a4b8cb3c Ronald S. Bultje
        pos = url_ftell(&pb);
308 4fce284c Ronald S. Bultje
        if (res < 0)
309
            return res;
310 c5efef7b Ronald S. Bultje
        if (res > 0) {
311
            if (st->codec->codec_id == CODEC_ID_AAC) {
312 c8829279 Ronald S. Bultje
                memcpy (rdt->buffer, buf + pos, len - pos);
313
                rdt->rmctx->pb = av_alloc_put_byte (rdt->buffer, len - pos, 0,
314
                                                    NULL, NULL, NULL, NULL);
315 c5efef7b Ronald S. Bultje
            }
316
            goto get_cache;
317 4fce284c Ronald S. Bultje
        }
318
    } else {
319 c5efef7b Ronald S. Bultje
get_cache:
320 a9f84821 Ronald S. Bultje
        rdt->audio_pkt_cnt =
321 ade8fb4d Ronald S. Bultje
            ff_rm_retrieve_cache (rdt->rmctx, rdt->rmctx->pb,
322 7c68a177 Ronald S. Bultje
                                  st, rdt->rmst[st->index], pkt);
323 5d88c264 Ronald S. Bultje
        if (rdt->audio_pkt_cnt == 0 &&
324 4fce284c Ronald S. Bultje
            st->codec->codec_id == CODEC_ID_AAC)
325 a4b8cb3c Ronald S. Bultje
            av_freep(&rdt->rmctx->pb);
326 4fce284c Ronald S. Bultje
    }
327
    pkt->stream_index = st->index;
328
    pkt->pts = *timestamp;
329
330 5d88c264 Ronald S. Bultje
    return rdt->audio_pkt_cnt > 0;
331 4fce284c Ronald S. Bultje
}
332
333
int
334 accc248f Ronald S. Bultje
ff_rdt_parse_packet(RDTDemuxContext *s, AVPacket *pkt,
335 ad4ad27f Martin Storsjö
                    uint8_t **bufptr, int len)
336 4fce284c Ronald S. Bultje
{
337 ad4ad27f Martin Storsjö
    uint8_t *buf = bufptr ? *bufptr : NULL;
338 114732f4 Ronald S. Bultje
    int seq_no, flags = 0, stream_id, set_id, is_keyframe;
339 4fce284c Ronald S. Bultje
    uint32_t timestamp;
340
    int rv= 0;
341
342 3ff2a062 Ronald S. Bultje
    if (!s->parse_packet)
343
        return -1;
344
345 7960e18f Ronald S. Bultje
    if (!buf && s->prev_stream_id != -1) {
346 4fce284c Ronald S. Bultje
        /* return the next packets, if any */
347
        timestamp= 0; ///< Should not be used if buf is NULL, but should be set to the timestamp of the packet returned....
348 1a45a9f4 Ronald S. Bultje
        rv= s->parse_packet(s->ic, s->dynamic_protocol_context,
349 7960e18f Ronald S. Bultje
                            s->streams[s->prev_stream_id],
350
                            pkt, &timestamp, NULL, 0, flags);
351 4fce284c Ronald S. Bultje
        return rv;
352
    }
353
354
    if (len < 12)
355
        return -1;
356 114732f4 Ronald S. Bultje
    rv = ff_rdt_parse_header(buf, len, &set_id, &seq_no, &stream_id, &is_keyframe, &timestamp);
357 4fce284c Ronald S. Bultje
    if (rv < 0)
358
        return rv;
359 7960e18f Ronald S. Bultje
    if (is_keyframe &&
360
        (set_id != s->prev_set_id || timestamp != s->prev_timestamp ||
361
         stream_id != s->prev_stream_id)) {
362 a68d44ed Ronald S. Bultje
        flags |= RTP_FLAG_KEY;
363 239dec21 Ronald S. Bultje
        s->prev_set_id    = set_id;
364
        s->prev_timestamp = timestamp;
365 985b05d3 Ronald S. Bultje
    }
366 7960e18f Ronald S. Bultje
    s->prev_stream_id = stream_id;
367 4fce284c Ronald S. Bultje
    buf += rv;
368
    len -= rv;
369
370 7960e18f Ronald S. Bultje
     if (s->prev_stream_id >= s->n_streams) {
371
         s->prev_stream_id = -1;
372
         return -1;
373
     }
374
375 1a45a9f4 Ronald S. Bultje
    rv = s->parse_packet(s->ic, s->dynamic_protocol_context,
376 7960e18f Ronald S. Bultje
                         s->streams[s->prev_stream_id],
377
                         pkt, &timestamp, buf, len, flags);
378 4fce284c Ronald S. Bultje
379
    return rv;
380
}
381
382 1256d16b Ronald S. Bultje
void
383 ab63fb03 Ronald S. Bultje
ff_rdt_subscribe_rule (char *cmd, int size,
384 1256d16b Ronald S. Bultje
                       int stream_nr, int rule_nr)
385
{
386
    av_strlcatf(cmd, size, "stream=%d;rule=%d,stream=%d;rule=%d",
387 ab63fb03 Ronald S. Bultje
                stream_nr, rule_nr * 2, stream_nr, rule_nr * 2 + 1);
388
}
389
390 ff13ba92 Ronald S. Bultje
static unsigned char *
391
rdt_parse_b64buf (unsigned int *target_len, const char *p)
392
{
393
    unsigned char *target;
394
    int len = strlen(p);
395
    if (*p == '\"') {
396
        p++;
397
        len -= 2; /* skip embracing " at start/end */
398
    }
399
    *target_len = len * 3 / 4;
400
    target = av_mallocz(*target_len + FF_INPUT_BUFFER_PADDING_SIZE);
401
    av_base64_decode(target, p, *target_len);
402
    return target;
403
}
404
405
static int
406 7b2a0708 Ronald S. Bultje
rdt_parse_sdp_line (AVFormatContext *s, int st_index,
407
                    PayloadContext *rdt, const char *line)
408 ff13ba92 Ronald S. Bultje
{
409 7b2a0708 Ronald S. Bultje
    AVStream *stream = s->streams[st_index];
410 ff13ba92 Ronald S. Bultje
    const char *p = line;
411
412
    if (av_strstart(p, "OpaqueData:buffer;", &p)) {
413
        rdt->mlti_data = rdt_parse_b64buf(&rdt->mlti_data_size, p);
414
    } else if (av_strstart(p, "StartTime:integer;", &p))
415
        stream->first_dts = atoi(p);
416 7c68a177 Ronald S. Bultje
    else if (av_strstart(p, "ASMRuleBook:string;", &p)) {
417 0b9535b9 Ronald S. Bultje
        int n, first = -1;
418 7c68a177 Ronald S. Bultje
419
        for (n = 0; n < s->nb_streams; n++)
420 b2dd842d Martin Storsjö
            if (s->streams[n]->id == stream->id) {
421 dfdb353c Aurelien Jacobs
                int count = s->streams[n]->index + 1;
422 7c68a177 Ronald S. Bultje
                if (first == -1) first = n;
423 dfdb353c Aurelien Jacobs
                if (rdt->nb_rmst < count) {
424
                    RMStream **rmst= av_realloc(rdt->rmst, count*sizeof(*rmst));
425
                    if (!rmst)
426
                        return AVERROR(ENOMEM);
427
                    memset(rmst + rdt->nb_rmst, 0,
428
                           (count - rdt->nb_rmst) * sizeof(*rmst));
429
                    rdt->rmst    = rmst;
430
                    rdt->nb_rmst = count;
431
                }
432 7c68a177 Ronald S. Bultje
                rdt->rmst[s->streams[n]->index] = ff_rm_alloc_rmstream();
433
                rdt_load_mdpr(rdt, s->streams[n], (n - first) * 2);
434
435
                if (s->streams[n]->codec->codec_id == CODEC_ID_AAC)
436
                    s->streams[n]->codec->frame_size = 1; // FIXME
437
           }
438
    }
439 ff13ba92 Ronald S. Bultje
440
    return 0;
441
}
442
443 530bca94 Ronald S. Bultje
static void
444
real_parse_asm_rule(AVStream *st, const char *p, const char *end)
445
{
446
    do {
447
        /* can be either averagebandwidth= or AverageBandwidth= */
448
        if (sscanf(p, " %*1[Aa]verage%*1[Bb]andwidth=%d", &st->codec->bit_rate) == 1)
449
            break;
450
        if (!(p = strchr(p, ',')) || p > end)
451
            p = end;
452
        p++;
453
    } while (p < end);
454
}
455
456 3ca45429 Ronald S. Bultje
static AVStream *
457
add_dstream(AVFormatContext *s, AVStream *orig_st)
458
{
459
    AVStream *st;
460
461 b2dd842d Martin Storsjö
    if (!(st = av_new_stream(s, orig_st->id)))
462 3ca45429 Ronald S. Bultje
        return NULL;
463
    st->codec->codec_type = orig_st->codec->codec_type;
464
    st->first_dts         = orig_st->first_dts;
465
466
    return st;
467
}
468
469
static void
470
real_parse_asm_rulebook(AVFormatContext *s, AVStream *orig_st,
471
                        const char *p)
472
{
473
    const char *end;
474 dfdb353c Aurelien Jacobs
    int n_rules = 0, odd = 0;
475 3ca45429 Ronald S. Bultje
    AVStream *st;
476
477
    /**
478
     * The ASMRuleBook contains a list of comma-separated strings per rule,
479
     * and each rule is separated by a ;. The last one also has a ; at the
480
     * end so we can use it as delimiter.
481
     * Every rule occurs twice, once for when the RTSP packet header marker
482
     * is set and once for if it isn't. We only read the first because we
483
     * don't care much (that's what the "odd" variable is for).
484
     * Each rule contains a set of one or more statements, optionally
485
     * preceeded by a single condition. If there's a condition, the rule
486
     * starts with a '#'. Multiple conditions are merged between brackets,
487
     * so there are never multiple conditions spread out over separate
488
     * statements. Generally, these conditions are bitrate limits (min/max)
489
     * for multi-bitrate streams.
490
     */
491
    if (*p == '\"') p++;
492 dfdb353c Aurelien Jacobs
    while (1) {
493 3ca45429 Ronald S. Bultje
        if (!(end = strchr(p, ';')))
494
            break;
495
        if (!odd && end != p) {
496
            if (n_rules > 0)
497
                st = add_dstream(s, orig_st);
498
            else
499
                st = orig_st;
500 dfdb353c Aurelien Jacobs
            if (!st)
501
                break;
502 530bca94 Ronald S. Bultje
            real_parse_asm_rule(st, p, end);
503 3ca45429 Ronald S. Bultje
            n_rules++;
504
        }
505
        p = end + 1;
506
        odd ^= 1;
507
    }
508
}
509
510
void
511
ff_real_parse_sdp_a_line (AVFormatContext *s, int stream_index,
512
                          const char *line)
513
{
514
    const char *p = line;
515
516
    if (av_strstart(p, "ASMRuleBook:string;", &p))
517
        real_parse_asm_rulebook(s, s->streams[stream_index], p);
518
}
519
520 ed0aacc7 Ronald S. Bultje
static PayloadContext *
521 202a6697 Colin McQuillan
rdt_new_context (void)
522 ff13ba92 Ronald S. Bultje
{
523 ed0aacc7 Ronald S. Bultje
    PayloadContext *rdt = av_mallocz(sizeof(PayloadContext));
524 ff13ba92 Ronald S. Bultje
525 c6610a21 Diego Elio Pettenò
    av_open_input_stream(&rdt->rmctx, NULL, "", &ff_rdt_demuxer, NULL);
526 ff13ba92 Ronald S. Bultje
527
    return rdt;
528
}
529
530
static void
531 202a6697 Colin McQuillan
rdt_free_context (PayloadContext *rdt)
532 ff13ba92 Ronald S. Bultje
{
533 7c68a177 Ronald S. Bultje
    int i;
534
535 dfdb353c Aurelien Jacobs
    for (i = 0; i < rdt->nb_rmst; i++)
536 7c68a177 Ronald S. Bultje
        if (rdt->rmst[i]) {
537
            ff_rm_free_rmstream(rdt->rmst[i]);
538
            av_freep(&rdt->rmst[i]);
539
        }
540 ff13ba92 Ronald S. Bultje
    if (rdt->rmctx)
541
        av_close_input_stream(rdt->rmctx);
542
    av_freep(&rdt->mlti_data);
543 dfdb353c Aurelien Jacobs
    av_freep(&rdt->rmst);
544 ff13ba92 Ronald S. Bultje
    av_free(rdt);
545
}
546
547
#define RDT_HANDLER(n, s, t) \
548
static RTPDynamicProtocolHandler ff_rdt_ ## n ## _handler = { \
549 202a6697 Colin McQuillan
    .enc_name         = s, \
550
    .codec_type       = t, \
551
    .codec_id         = CODEC_ID_NONE, \
552
    .parse_sdp_a_line = rdt_parse_sdp_line, \
553
    .open             = rdt_new_context, \
554
    .close            = rdt_free_context, \
555
    .parse_packet     = rdt_parse_packet \
556 44adbebe Mans Rullgard
}
557 ff13ba92 Ronald S. Bultje
558 72415b2a Stefano Sabatini
RDT_HANDLER(live_video, "x-pn-multirate-realvideo-live", AVMEDIA_TYPE_VIDEO);
559
RDT_HANDLER(live_audio, "x-pn-multirate-realaudio-live", AVMEDIA_TYPE_AUDIO);
560
RDT_HANDLER(video,      "x-pn-realvideo",                AVMEDIA_TYPE_VIDEO);
561
RDT_HANDLER(audio,      "x-pn-realaudio",                AVMEDIA_TYPE_AUDIO);
562 ff13ba92 Ronald S. Bultje
563
void av_register_rdt_dynamic_payload_handlers(void)
564
{
565
    ff_register_dynamic_payload_handler(&ff_rdt_video_handler);
566
    ff_register_dynamic_payload_handler(&ff_rdt_audio_handler);
567
    ff_register_dynamic_payload_handler(&ff_rdt_live_video_handler);
568
    ff_register_dynamic_payload_handler(&ff_rdt_live_audio_handler);
569
}