avformat/libsrt: add latency options and deprecate tspbdelay

Signed-off-by: Sven Dueking <sven.dueking@nablet.com>
Signed-off-by: Luca Barbato <lu_zero@gentoo.org>

configure

@@ -4691,7 +4691,7 @@ enabled librtmp           && require_pkg_config librtmp librtmp librtmp/rtmp.h R
 enabled libschroedinger   && require_pkg_config libschroedinger schroedinger-1.0 schroedinger/schro.h schro_init
 enabled libsnappy         && require libsnappy snappy-c.h snappy_compress -lsnappy
 enabled libspeex          && require_pkg_config libspeex speex speex/speex.h speex_decoder_init
-enabled libsrt            && require_pkg_config libsrt "srt >= 1.2.0" srt/srt.h srt_socket
+enabled libsrt            && require_pkg_config libsrt "srt >= 1.3.0" srt/srt.h srt_socket
 enabled libtheora         && require libtheora theora/theoraenc.h th_info_init -ltheoraenc -ltheoradec -logg
 enabled libtwolame        && require libtwolame twolame.h twolame_init -ltwolame
 enabled libvo_aacenc      && require libvo_aacenc vo-aacenc/voAAC.h voGetAACEncAPI -lvo-aacenc

doc/protocols.texi

@@ -710,6 +710,17 @@ IP Type of Service. Applies to sender only. Default value is 0xB8.
 @item ipttl=@var{ttl}
 IP Time To Live. Applies to sender only. Default value is 64.
 
+@item latency
+Timestamp-based Packet Delivery Delay.
+Used to absorb bursts of missed packet retransmissions.
+This flag sets both @option{rcvlatency} and @option{peerlatency}
+to the same value. Note that prior to version 1.3.0
+this is the only flag to set the latency, however
+this is effectively equivalent to setting @option{peerlatency},
+when side is sender and @option{rcvlatency}
+when side is receiver, and the bidirectional stream
+sending is not supported.
+
 @item listen_timeout
 Set socket listen timeout.
 
@@ -766,6 +777,10 @@ wrapping a live stream in very small frames, then you can
 use a bigger maximum frame size, though not greater than
 1456 bytes.
 
+@item peerlatency
+The latency value (as described in @option{rcvlatency}) that is
+set by the sender side as a minimum value for the receiver.
+
 @item pbkeylen=@var{bytes}
 Sender encryption key length, in bytes.
 Only can be set to 0, 16, 24 and 32.
@@ -774,6 +789,18 @@ Not required on receiver (set to 0),
 key size obtained from sender in HaiCrypt handshake.
 Default value is 0.
 
+@item rcvlatency
+The time that should elapse since the moment when the
+packet was sent and the moment when it's delivered to
+the receiver application in the receiving function.
+This time should be a buffer time large enough to cover
+the time spent for sending, unexpectedly extended RTT
+time, and the time needed to retransmit the lost UDP
+packet. The effective latency value will be the maximum
+of this options' value and the value of @option{peerlatency}
+set by the peer side. Before version 1.3.0 this option
+is only available as @option{latency}.
+
 @item recv_buffer_size=@var{bytes}
 Set receive buffer size, expressed in bytes.
 
@@ -798,10 +825,6 @@ have no chance of being delivered in time. It was
 automatically enabled in the sender if the receiver
 supports it.
 
-@item tsbpddelay
-Timestamp-based Packet Delivery Delay.
-Used to absorb burst of missed packet retransmission.
-
 @end table
 
 For more information see: @url{https://github.com/Haivision/srt}.

libavformat/libsrt.c

@@ -68,11 +68,13 @@ typedef struct SRTContext {
     int iptos;
     int64_t inputbw;
     int oheadbw;
-    int64_t tsbpddelay;
+    int64_t latency;
     int tlpktdrop;
     int nakreport;
     int64_t connect_timeout;
     int payload_size;
+    int64_t rcvlatency;
+    int64_t peerlatency;
     enum SRTMode mode;
 } SRTContext;
 
@@ -93,7 +95,10 @@ static const AVOption libsrt_options[] = {
     { "iptos",          "IP Type of Service",                                                   OFFSET(iptos),            AV_OPT_TYPE_INT,      { .i64 = -1 }, -1, 255,       .flags = D|E },
     { "inputbw",        "Estimated input stream rate",                                          OFFSET(inputbw),          AV_OPT_TYPE_INT64,    { .i64 = -1 }, -1, INT64_MAX, .flags = D|E },
     { "oheadbw",        "MaxBW ceiling based on % over input stream rate",                      OFFSET(oheadbw),          AV_OPT_TYPE_INT,      { .i64 = -1 }, -1, 100,       .flags = D|E },
-    { "tsbpddelay",     "TsbPd receiver delay to absorb burst of missed packet retransmission", OFFSET(tsbpddelay),       AV_OPT_TYPE_INT64, { .i64 = -1 }, -1, INT64_MAX, .flags = D|E },
+    { "latency",        "receiver delay to absorb bursts of missed packet retransmissions",     OFFSET(latency),          AV_OPT_TYPE_INT64, { .i64 = -1 }, -1, INT64_MAX, .flags = D|E },
+    { "tsbpddelay",     "deprecated, same effect as latency option",                            OFFSET(latency),          AV_OPT_TYPE_INT64, { .i64 = -1 }, -1, INT64_MAX, .flags = D|E },
+    { "rcvlatency",     "receive latency",                                                      OFFSET(rcvlatency),       AV_OPT_TYPE_INT64, { .i64 = -1 }, -1, INT64_MAX, .flags = D|E },
+    { "peerlatency",    "peer latency",                                                         OFFSET(peerlatency),      AV_OPT_TYPE_INT64, { .i64 = -1 }, -1, INT64_MAX, .flags = D|E },
     { "tlpktdrop",      "Enable receiver pkt drop",                                             OFFSET(tlpktdrop),        AV_OPT_TYPE_INT,      { .i64 = -1 }, -1, 1,         .flags = D|E },
     { "nakreport",      "Enable receiver to send periodic NAK reports",                         OFFSET(nakreport),        AV_OPT_TYPE_INT,      { .i64 = -1 }, -1, 1,         .flags = D|E },
     { "connect_timeout", "Connect timeout. Caller default: 3000, rendezvous (x 10)",            OFFSET(connect_timeout),  AV_OPT_TYPE_INT64, { .i64 = -1 }, -1, INT64_MAX, .flags = D|E },
@@ -276,7 +281,9 @@ static int libsrt_set_options_pre(URLContext *h, int fd)
 {
     SRTContext *s = h->priv_data;
     int yes = 1;
-    int tsbpddelay = s->tsbpddelay / 1000;
+    int latency = s->latency / 1000;
+    int rcvlatency = s->rcvlatency / 1000;
+    int peerlatency = s->peerlatency / 1000;
     int connect_timeout = s->connect_timeout;
 
     if ((s->mode == SRT_MODE_RENDEZVOUS && libsrt_setsockopt(h, fd, SRTO_RENDEZVOUS, "SRTO_RENDEZVOUS", &yes, sizeof(yes)) < 0) ||
@@ -287,7 +294,9 @@ static int libsrt_set_options_pre(URLContext *h, int fd)
         (s->ffs >= 0 && libsrt_setsockopt(h, fd, SRTO_FC, "SRTO_FC", &s->ffs, sizeof(s->ffs)) < 0) ||
         (s->ipttl >= 0 && libsrt_setsockopt(h, fd, SRTO_IPTTL, "SRTO_UPTTL", &s->ipttl, sizeof(s->ipttl)) < 0) ||
         (s->iptos >= 0 && libsrt_setsockopt(h, fd, SRTO_IPTOS, "SRTO_IPTOS", &s->iptos, sizeof(s->iptos)) < 0) ||
-        (tsbpddelay >= 0 && libsrt_setsockopt(h, fd, SRTO_TSBPDDELAY, "SRTO_TSBPDELAY", &tsbpddelay, sizeof(tsbpddelay)) < 0) ||
+        (s->latency >= 0 && libsrt_setsockopt(h, fd, SRTO_LATENCY, "SRTO_LATENCY", &latency, sizeof(latency)) < 0) ||
+        (s->rcvlatency >= 0 && libsrt_setsockopt(h, fd, SRTO_RCVLATENCY, "SRTO_RCVLATENCY", &rcvlatency, sizeof(rcvlatency)) < 0) ||
+        (s->peerlatency >= 0 && libsrt_setsockopt(h, fd, SRTO_PEERLATENCY, "SRTO_PEERLATENCY", &peerlatency, sizeof(peerlatency)) < 0) ||
         (s->tlpktdrop >= 0 && libsrt_setsockopt(h, fd, SRTO_TLPKTDROP, "SRTO_TLPKDROP", &s->tlpktdrop, sizeof(s->tlpktdrop)) < 0) ||
         (s->nakreport >= 0 && libsrt_setsockopt(h, fd, SRTO_NAKREPORT, "SRTO_NAKREPORT", &s->nakreport, sizeof(s->nakreport)) < 0) ||
         (connect_timeout >= 0 && libsrt_setsockopt(h, fd, SRTO_CONNTIMEO, "SRTO_CONNTIMEO", &connect_timeout, sizeof(connect_timeout)) < 0) ||
@@ -457,8 +466,17 @@ static int libsrt_open(URLContext *h, const char *uri, int flags)
         if (av_find_info_tag(buf, sizeof(buf), "oheadbw", p)) {
             s->oheadbw = strtoll(buf, NULL, 10);
         }
+        if (av_find_info_tag(buf, sizeof(buf), "latency", p)) {
+            s->latency = strtol(buf, NULL, 10);
+        }
         if (av_find_info_tag(buf, sizeof(buf), "tsbpddelay", p)) {
-            s->tsbpddelay = strtol(buf, NULL, 10);
+            s->latency = strtol(buf, NULL, 10);
+        }
+        if (av_find_info_tag(buf, sizeof(buf), "rcvlatency", p)) {
+            s->rcvlatency = strtol(buf, NULL, 10);
+        }
+        if (av_find_info_tag(buf, sizeof(buf), "peerlatency", p)) {
+            s->peerlatency = strtol(buf, NULL, 10);
         }
         if (av_find_info_tag(buf, sizeof(buf), "tlpktdrop", p)) {
             s->tlpktdrop = strtol(buf, NULL, 10);