481 lines
14 KiB
C
481 lines
14 KiB
C
/*
|
|
* Pro-MPEG Code of Practice #3 Release 2 FEC
|
|
* Copyright (c) 2016 Mobibase, France (http://www.mobibase.com)
|
|
*
|
|
* 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
|
|
* Pro-MPEG Code of Practice #3 Release 2 FEC protocol
|
|
* @author Vlad Tarca <vlad.tarca@gmail.com>
|
|
*/
|
|
|
|
/*
|
|
* Reminder:
|
|
|
|
[RFC 2733] FEC Packet Structure
|
|
|
|
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
|
|
| RTP Header |
|
|
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
|
|
| FEC Header |
|
|
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
|
|
| FEC Payload |
|
|
| |
|
|
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
|
|
|
|
|
|
[RFC 3550] RTP header
|
|
|
|
0 1 2 3
|
|
0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
|
|
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
|
|
|V=2|P|X| CC |M| PT | sequence number |
|
|
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
|
|
| timestamp |
|
|
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
|
|
| synchronization source (SSRC) identifier |
|
|
+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+
|
|
| contributing source (CSRC) identifiers |
|
|
| .... |
|
|
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
|
|
|
|
[RFC 3550] RTP header extension (after CSRC)
|
|
|
|
0 1 2 3
|
|
0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
|
|
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
|
|
| defined by profile | length |
|
|
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
|
|
| header extension |
|
|
| .... |
|
|
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
|
|
|
|
[Pro-MPEG COP3] FEC Header
|
|
|
|
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
|
|
| SNBase low bits | length recovery |
|
|
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
|
|
|E| PT recovery | mask |
|
|
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
|
|
| TS recovery |
|
|
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
|
|
|X|D|type |index| offset | NA |SNBase ext bits|
|
|
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
|
|
|
|
*/
|
|
|
|
#include "libavutil/avstring.h"
|
|
#include "libavutil/intreadwrite.h"
|
|
#include "libavutil/opt.h"
|
|
#include "libavutil/parseutils.h"
|
|
#include "libavutil/random_seed.h"
|
|
#include "avformat.h"
|
|
#include "config.h"
|
|
#include "url.h"
|
|
|
|
#define PROMPEG_RTP_PT 0x60
|
|
#define PROMPEG_FEC_COL 0x0
|
|
#define PROMPEG_FEC_ROW 0x1
|
|
|
|
typedef struct PrompegFec {
|
|
uint16_t sn;
|
|
uint32_t ts;
|
|
uint8_t *bitstring;
|
|
} PrompegFec;
|
|
|
|
typedef struct PrompegContext {
|
|
const AVClass *class;
|
|
URLContext *fec_col_hd, *fec_row_hd;
|
|
PrompegFec **fec_arr, **fec_col_tmp, **fec_col, *fec_row;
|
|
int ttl;
|
|
uint8_t l, d;
|
|
uint8_t *rtp_buf;
|
|
uint16_t rtp_col_sn, rtp_row_sn;
|
|
uint16_t length_recovery;
|
|
int packet_size;
|
|
int packet_idx, packet_idx_max;
|
|
int fec_arr_len;
|
|
int bitstring_size;
|
|
int rtp_buf_size;
|
|
int init;
|
|
int first;
|
|
} PrompegContext;
|
|
|
|
#define OFFSET(x) offsetof(PrompegContext, x)
|
|
#define E AV_OPT_FLAG_ENCODING_PARAM
|
|
|
|
static const AVOption options[] = {
|
|
{ "ttl", "Time to live (in milliseconds, multicast only)", OFFSET(ttl), AV_OPT_TYPE_INT, { .i64 = -1 }, -1, INT_MAX, .flags = E },
|
|
{ "l", "FEC L", OFFSET(l), AV_OPT_TYPE_INT, { .i64 = 5 }, 4, 20, .flags = E },
|
|
{ "d", "FEC D", OFFSET(d), AV_OPT_TYPE_INT, { .i64 = 5 }, 4, 20, .flags = E },
|
|
{ NULL }
|
|
};
|
|
|
|
static const AVClass prompeg_class = {
|
|
.class_name = "prompeg",
|
|
.item_name = av_default_item_name,
|
|
.option = options,
|
|
.version = LIBAVUTIL_VERSION_INT,
|
|
};
|
|
|
|
static void xor_fast(const uint8_t *in1, const uint8_t *in2, uint8_t *out, int size) {
|
|
int i, n, s;
|
|
|
|
#if HAVE_FAST_64BIT
|
|
uint64_t v1, v2;
|
|
|
|
n = size / sizeof (uint64_t);
|
|
s = n * sizeof (uint64_t);
|
|
|
|
for (i = 0; i < n; i++) {
|
|
v1 = AV_RN64A(in1);
|
|
v2 = AV_RN64A(in2);
|
|
AV_WN64A(out, v1 ^ v2);
|
|
in1 += 8;
|
|
in2 += 8;
|
|
out += 8;
|
|
}
|
|
#else
|
|
uint32_t v1, v2;
|
|
|
|
n = size / sizeof (uint32_t);
|
|
s = n * sizeof (uint32_t);
|
|
|
|
for (i = 0; i < n; i++) {
|
|
v1 = AV_RN32A(in1);
|
|
v2 = AV_RN32A(in2);
|
|
AV_WN32A(out, v1 ^ v2);
|
|
in1 += 4;
|
|
in2 += 4;
|
|
out += 4;
|
|
}
|
|
#endif
|
|
|
|
n = size - s;
|
|
|
|
for (i = 0; i < n; i++) {
|
|
out[i] = in1[i] ^ in2[i];
|
|
}
|
|
}
|
|
|
|
static int prompeg_create_bitstring(URLContext *h, const uint8_t *buf, int size,
|
|
uint8_t **bitstring) {
|
|
PrompegContext *s = h->priv_data;
|
|
uint8_t *b;
|
|
|
|
if (size < 12 || (buf[0] & 0xc0) != 0x80 || (buf[1] & 0x7f) != 0x21) {
|
|
av_log(h, AV_LOG_ERROR, "Unsupported stream format (expected MPEG-TS over RTP)\n");
|
|
return AVERROR(EINVAL);
|
|
}
|
|
if (size != s->packet_size) {
|
|
av_log(h, AV_LOG_ERROR, "The RTP packet size must be constant (set pkt_size)\n");
|
|
return AVERROR(EINVAL);
|
|
}
|
|
|
|
*bitstring = av_malloc(s->bitstring_size);
|
|
if (!*bitstring) {
|
|
av_log(h, AV_LOG_ERROR, "Failed to allocate the bitstring buffer\n");
|
|
return AVERROR(ENOMEM);
|
|
}
|
|
b = *bitstring;
|
|
|
|
// P, X, CC
|
|
b[0] = buf[0] & 0x3f;
|
|
// M, PT
|
|
b[1] = buf[1];
|
|
// Timestamp
|
|
b[2] = buf[4];
|
|
b[3] = buf[5];
|
|
b[4] = buf[6];
|
|
b[5] = buf[7];
|
|
/*
|
|
* length_recovery: the unsigned network-ordered sum of lengths of CSRC,
|
|
* padding, extension and media payload
|
|
*/
|
|
AV_WB16(b + 6, s->length_recovery);
|
|
// Payload
|
|
memcpy(b + 8, buf + 12, s->length_recovery);
|
|
|
|
return 0;
|
|
}
|
|
|
|
static int prompeg_write_fec(URLContext *h, PrompegFec *fec, uint8_t type) {
|
|
PrompegContext *s = h->priv_data;
|
|
URLContext *hd;
|
|
uint8_t *buf = s->rtp_buf; // zero-filled
|
|
uint8_t *b = fec->bitstring;
|
|
uint16_t sn;
|
|
int ret;
|
|
|
|
sn = type == PROMPEG_FEC_COL ? ++s->rtp_col_sn : ++s->rtp_row_sn;
|
|
|
|
// V, P, X, CC
|
|
buf[0] = 0x80 | (b[0] & 0x3f);
|
|
// M, PT
|
|
buf[1] = (b[1] & 0x80) | PROMPEG_RTP_PT;
|
|
// SN
|
|
AV_WB16(buf + 2, sn);
|
|
// TS
|
|
AV_WB32(buf + 4, fec->ts);
|
|
// CSRC=0
|
|
//AV_WB32(buf + 8, 0);
|
|
// SNBase low bits
|
|
AV_WB16(buf + 12, fec->sn);
|
|
// Length recovery
|
|
buf[14] = b[6];
|
|
buf[15] = b[7];
|
|
// E=1, PT recovery
|
|
buf[16] = 0x80 | b[1];
|
|
// Mask=0
|
|
//buf[17] = 0x0;
|
|
//buf[18] = 0x0;
|
|
//buf[19] = 0x0;
|
|
// TS recovery
|
|
buf[20] = b[2];
|
|
buf[21] = b[3];
|
|
buf[22] = b[4];
|
|
buf[23] = b[5];
|
|
// X=0, D, type=0, index=0
|
|
buf[24] = type == PROMPEG_FEC_COL ? 0x0 : 0x40;
|
|
// offset
|
|
buf[25] = type == PROMPEG_FEC_COL ? s->l : 0x1;
|
|
// NA
|
|
buf[26] = type == PROMPEG_FEC_COL ? s->d : s->l;
|
|
// SNBase ext bits=0
|
|
//buf[27] = 0x0;
|
|
// Payload
|
|
memcpy(buf + 28, b + 8, s->length_recovery);
|
|
|
|
hd = type == PROMPEG_FEC_COL ? s->fec_col_hd : s->fec_row_hd;
|
|
ret = ffurl_write(hd, buf, s->rtp_buf_size);
|
|
return ret;
|
|
}
|
|
|
|
static int prompeg_open(URLContext *h, const char *uri, int flags) {
|
|
PrompegContext *s = h->priv_data;
|
|
AVDictionary *udp_opts = NULL;
|
|
int rtp_port;
|
|
char hostname[256];
|
|
char buf[1024];
|
|
|
|
s->fec_col_hd = NULL;
|
|
s->fec_row_hd = NULL;
|
|
|
|
if (s->l * s->d > 100) {
|
|
av_log(h, AV_LOG_ERROR, "L * D must be <= 100\n");
|
|
return AVERROR(EINVAL);
|
|
}
|
|
|
|
av_url_split(NULL, 0, NULL, 0, hostname, sizeof (hostname), &rtp_port,
|
|
NULL, 0, uri);
|
|
|
|
if (rtp_port < 1 || rtp_port > UINT16_MAX - 4) {
|
|
av_log(h, AV_LOG_ERROR, "Invalid RTP base port %d\n", rtp_port);
|
|
return AVERROR(EINVAL);
|
|
}
|
|
|
|
if (s->ttl > 0) {
|
|
av_dict_set_int(&udp_opts, "ttl", s->ttl, 0);
|
|
}
|
|
|
|
ff_url_join(buf, sizeof (buf), "udp", NULL, hostname, rtp_port + 2, NULL);
|
|
if (ffurl_open_whitelist(&s->fec_col_hd, buf, flags, &h->interrupt_callback,
|
|
&udp_opts, h->protocol_whitelist, h->protocol_blacklist, h) < 0)
|
|
goto fail;
|
|
ff_url_join(buf, sizeof (buf), "udp", NULL, hostname, rtp_port + 4, NULL);
|
|
if (ffurl_open_whitelist(&s->fec_row_hd, buf, flags, &h->interrupt_callback,
|
|
&udp_opts, h->protocol_whitelist, h->protocol_blacklist, h) < 0)
|
|
goto fail;
|
|
|
|
h->max_packet_size = s->fec_col_hd->max_packet_size;
|
|
s->init = 1;
|
|
|
|
av_dict_free(&udp_opts);
|
|
av_log(h, AV_LOG_INFO, "ProMPEG CoP#3-R2 FEC L=%d D=%d\n", s->l, s->d);
|
|
return 0;
|
|
|
|
fail:
|
|
ffurl_closep(&s->fec_col_hd);
|
|
ffurl_closep(&s->fec_row_hd);
|
|
av_dict_free(&udp_opts);
|
|
return AVERROR(EIO);
|
|
}
|
|
|
|
static int prompeg_init(URLContext *h, const uint8_t *buf, int size) {
|
|
PrompegContext *s = h->priv_data;
|
|
uint32_t seed;
|
|
int i;
|
|
|
|
s->fec_arr = NULL;
|
|
s->rtp_buf = NULL;
|
|
|
|
if (size < 12 || size > UINT16_MAX + 12) {
|
|
av_log(h, AV_LOG_ERROR, "Invalid RTP packet size\n");
|
|
return AVERROR_INVALIDDATA;
|
|
}
|
|
|
|
s->packet_idx = 0;
|
|
s->packet_idx_max = s->l * s->d;
|
|
s->packet_size = size;
|
|
s->length_recovery = size - 12;
|
|
s->rtp_buf_size = 28 + s->length_recovery; // 12 + 16: RTP + FEC headers
|
|
s->bitstring_size = 8 + s->length_recovery; // 8: P, X, CC, M, PT, SN, TS
|
|
s->fec_arr_len = 1 + 2 * s->l; // row + column tmp + column out
|
|
|
|
if (h->flags & AVFMT_FLAG_BITEXACT) {
|
|
s->rtp_col_sn = 0;
|
|
s->rtp_row_sn = 0;
|
|
} else {
|
|
seed = av_get_random_seed();
|
|
s->rtp_col_sn = seed & 0x0fff;
|
|
s->rtp_row_sn = (seed >> 16) & 0x0fff;
|
|
}
|
|
|
|
s->fec_arr = av_malloc_array(s->fec_arr_len, sizeof (PrompegFec*));
|
|
if (!s->fec_arr) {
|
|
goto fail;
|
|
}
|
|
for (i = 0; i < s->fec_arr_len; i++) {
|
|
s->fec_arr[i] = av_malloc(sizeof (PrompegFec));
|
|
if (!s->fec_arr[i]) {
|
|
goto fail;
|
|
}
|
|
s->fec_arr[i]->bitstring = av_malloc_array(s->bitstring_size, sizeof (uint8_t));
|
|
if (!s->fec_arr[i]->bitstring) {
|
|
av_freep(&s->fec_arr[i]);
|
|
goto fail;
|
|
}
|
|
}
|
|
s->fec_row = *s->fec_arr;
|
|
s->fec_col = s->fec_arr + 1;
|
|
s->fec_col_tmp = s->fec_arr + 1 + s->l;
|
|
|
|
s->rtp_buf = av_malloc_array(s->rtp_buf_size, sizeof (uint8_t));
|
|
if (!s->rtp_buf) {
|
|
goto fail;
|
|
}
|
|
memset(s->rtp_buf, 0, s->rtp_buf_size);
|
|
|
|
s->init = 0;
|
|
s->first = 1;
|
|
|
|
return 0;
|
|
|
|
fail:
|
|
av_log(h, AV_LOG_ERROR, "Failed to allocate the FEC buffer\n");
|
|
return AVERROR(ENOMEM);
|
|
}
|
|
|
|
static int prompeg_write(URLContext *h, const uint8_t *buf, int size) {
|
|
PrompegContext *s = h->priv_data;
|
|
PrompegFec *fec_tmp;
|
|
uint8_t *bitstring = NULL;
|
|
int col_idx, col_out_idx, row_idx;
|
|
int ret, written = 0;
|
|
|
|
if (s->init && ((ret = prompeg_init(h, buf, size)) < 0))
|
|
goto end;
|
|
|
|
if ((ret = prompeg_create_bitstring(h, buf, size, &bitstring)) < 0)
|
|
goto end;
|
|
|
|
col_idx = s->packet_idx % s->l;
|
|
row_idx = s->packet_idx / s->l % s->d;
|
|
|
|
// FEC' (row) send block-aligned, xor
|
|
if (col_idx == 0) {
|
|
if (!s->first || s->packet_idx > 0) {
|
|
if ((ret = prompeg_write_fec(h, s->fec_row, PROMPEG_FEC_ROW)) < 0)
|
|
goto end;
|
|
written += ret;
|
|
}
|
|
memcpy(s->fec_row->bitstring, bitstring, s->bitstring_size);
|
|
s->fec_row->sn = AV_RB16(buf + 2);
|
|
s->fec_row->ts = AV_RB32(buf + 4);
|
|
} else {
|
|
xor_fast(s->fec_row->bitstring, bitstring, s->fec_row->bitstring,
|
|
s->bitstring_size);
|
|
}
|
|
|
|
// FEC (column) xor
|
|
if (row_idx == 0) {
|
|
if (!s->first) {
|
|
// swap fec_col and fec_col_tmp
|
|
fec_tmp = s->fec_col[col_idx];
|
|
s->fec_col[col_idx] = s->fec_col_tmp[col_idx];
|
|
s->fec_col_tmp[col_idx] = fec_tmp;
|
|
}
|
|
memcpy(s->fec_col_tmp[col_idx]->bitstring, bitstring, s->bitstring_size);
|
|
s->fec_col_tmp[col_idx]->sn = AV_RB16(buf + 2);
|
|
s->fec_col_tmp[col_idx]->ts = AV_RB32(buf + 4);
|
|
} else {
|
|
xor_fast(s->fec_col_tmp[col_idx]->bitstring, bitstring,
|
|
s->fec_col_tmp[col_idx]->bitstring, s->bitstring_size);
|
|
}
|
|
|
|
// FEC (column) send block-aligned
|
|
if (!s->first && s->packet_idx % s->d == 0) {
|
|
col_out_idx = s->packet_idx / s->d;
|
|
if ((ret = prompeg_write_fec(h, s->fec_col[col_out_idx], PROMPEG_FEC_COL)) < 0)
|
|
goto end;
|
|
written += ret;
|
|
}
|
|
|
|
if (++s->packet_idx >= s->packet_idx_max) {
|
|
s->packet_idx = 0;
|
|
if (s->first)
|
|
s->first = 0;
|
|
}
|
|
|
|
ret = written;
|
|
|
|
end:
|
|
av_free(bitstring);
|
|
return ret;
|
|
}
|
|
|
|
static int prompeg_close(URLContext *h) {
|
|
PrompegContext *s = h->priv_data;
|
|
int i;
|
|
|
|
ffurl_closep(&s->fec_col_hd);
|
|
ffurl_closep(&s->fec_row_hd);
|
|
|
|
if (s->fec_arr) {
|
|
for (i = 0; i < s->fec_arr_len; i++) {
|
|
av_free(s->fec_arr[i]->bitstring);
|
|
av_freep(&s->fec_arr[i]);
|
|
}
|
|
av_freep(&s->fec_arr);
|
|
}
|
|
av_freep(&s->rtp_buf);
|
|
|
|
return 0;
|
|
}
|
|
|
|
const URLProtocol ff_prompeg_protocol = {
|
|
.name = "prompeg",
|
|
.url_open = prompeg_open,
|
|
.url_write = prompeg_write,
|
|
.url_close = prompeg_close,
|
|
.priv_data_size = sizeof(PrompegContext),
|
|
.flags = URL_PROTOCOL_FLAG_NETWORK,
|
|
.priv_data_class = &prompeg_class,
|
|
};
|