AES67 Target
AES67 Target properties for Script Engine. Streams the scene audio as uncompressed PCM (L24 or L16, 48 kHz) over RTP multicast, the open AES67 Audio-over-IP standard. Use it for professional, low-latency, high-quality audio monitoring and contribution outside Composer Desktop — including on the headless Linux runtime — to receivers such as ffplay, VLC, software AES67/RAVENNA sound cards, and Dante networks (which interoperate with AES67). The session is described by an SDP that is written to a file, shown in the panel, and announced via SAP for auto-discovery. Note: this version derives RTP timing from the engine audio clock and is not yet PTP-locked, so a single stream plays everywhere but multiple AES67 sources cannot be sample-accurately cross-locked.
| Property | Type | Access | Description |
|---|---|---|---|
ShowAdvancedOptions |
bool |
get/set |
Reveals advanced/expert properties in the panel. Off by default — flip to On to see fields like TTL, payload type, SDP file path and the extra channel pairs. |
AutoStart |
bool |
get/set |
When On, the AES67 target connects automatically when the project loads. Useful for unattended studio machines or automation rigs. |
MulticastAddress |
string |
get/set |
The IPv4 multicast group the RTP audio is sent to (224.0.0.0–239.255.255.255). AES67 deployments commonly use the 239.x range. Can only be changed before the target starts. |
Port |
int |
get/set |
UDP port for the RTP stream (default 5004, the AES67 convention). |
Ttl |
int |
get/set |
Multicast time-to-live (hop limit). 1 keeps traffic on the local subnet; raise it to cross routers. Also used for SAP announcements. |
PayloadType |
int |
get/set |
RTP dynamic payload type (96–127, default 96). Only change if a receiver requires a specific value. |
BitDepth |
Aes67BitDepth |
get/set |
PCM bit depth on the wire. L24 (default) is the AES67-preferred 24-bit payload; L16 is offered for receivers that handle 16-bit more reliably (e.g. VLC). |
SessionName |
string |
get/set |
Session name advertised in the SDP and via SAP. Shown by receivers when they discover the stream. |
SdpFilePath |
string |
get/set |
Path the generated .sdp file is written to. Leave empty to write a default file in the system temp folder. Point ffplay/VLC at this file to play the stream. |
AnnounceViaSap |
bool |
get/set |
When On, announce the session via SAP (RFC 2974) so SAP-aware receivers auto-discover it. The .sdp file is written regardless. |
AudioPairOneEnabled |
bool |
get/set |
Include audio pair 1 in the stream. |
AudioPairOneMapping |
AudioChannelMapping |
get/set |
Scene audio channel pair routed to AES67 pair 1. |
AudioPairTwoEnabled |
bool |
get/set |
Include audio pair 2 in the stream. |
AudioPairTwoMapping |
AudioChannelMapping |
get/set |
Scene audio channel pair routed to AES67 pair 2. |
AudioPairThreeEnabled |
bool |
get/set |
Include audio pair 3 in the stream. |
AudioPairThreeMapping |
AudioChannelMapping |
get/set |
Scene audio channel pair routed to AES67 pair 3. |
AudioPairFourEnabled |
bool |
get/set |
Include audio pair 4 in the stream. |
AudioPairFourMapping |
AudioChannelMapping |
get/set |
Scene audio channel pair routed to AES67 pair 4. |
ConnectionStatus |
ConnectionStatus |
get |
Current connection status (Disconnected, Connecting, Connected). Read-only. |
StartCommand |
Command |
get |
Begins streaming the audio over multicast and announcing the session. |
StopCommand |
Command |
get |
Stops the stream and removes the session announcement. |
StartedDateTime |
DateTime |
get |
Timestamp of when the target last started streaming (read-only). |
ChannelCount |
int |
get |
Number of audio channels currently being sent (read-only). |
SentPackets |
int |
get |
Total RTP packets sent since the target started (read-only, debug). |
PacketRate |
string |
get |
Current packet send rate (read-only). At ptime 1 ms this should sit near 1000 packets/sec when streaming. |
OutputBitrate |
string |
get |
Approximate output audio bitrate (read-only). For L24 stereo this is ~2.3 Mbps; scales with channel count and bit depth. A quick sanity check that the channel/bit-depth config matches what you expect. |
SendQueueDepth |
int |
get |
Number of audio frames waiting to be sent (read-only). Should hover near zero; a steadily growing value means the sender is falling behind the render loop. |
PacingCatchups |
int |
get |
Count of packets sent in catch-up mode because a render frame arrived late (read-only, debug). Steadily climbing indicates pacing bursts — the usual cause of receiver "jitter buffer full" glitches. |
SilentInputFrames |
int |
get |
Count of render frames that carried no audio (read-only, debug). A non-zero value points to an engine-side audio gap rather than a network problem. |
Ssrc |
string |
get |
RTP SSRC of the current session in hex (read-only). Match this against a receiver's view to confirm it is locked onto this exact stream. |
SdpText |
MultilineText |
get |
The generated SDP session description (read-only). Save this to a .sdp file or hand it to a receiver to play the stream. |
Inherits from: AbstractTarget.
See also: AES67 Target in Targets — user-facing introduction, screenshots, and section summaries.