The RIST output can be push streams or have them pulled to/from a RIST-enabled device. RIST seeks to provide reliable, high performance media transport by using UDP at the transport layer to avoid the inefficiencies of TCP, then layering on top Forward Error Correction and Retransmits to add the reliability inherently absent from UDP.
Zixi supports the following RIST profiles:
- Simple Profile (PUSH only) - The RIST Simple Profile provides best-in-class packet protection, as well as support for multi-link bonding and seamless switching.
- Main Profile (PUSH/PULL) – The RIST Main Profile builds upon the features of the Simple Profile to provide backwards compatibility, while opening the door for additional features, including:
- Encryption and authentication - RIST Main Profile uses industry-standard DTLS or PSK with a variety of available cyphers to ensure the most up-to-date protection, while being flexible to accommodate local legal regulations. Support for pre-shared keys is also included, which makes RIST Main Profile compatible with one-to-many environments such as satellite or multicast distribution.
- Native tunneling and multiplexing - the ability to combine multiple Simple Profile RIST streams into one single connection, optionally with one single encryption and authentication step, using industry-standard GRE over UDP.
- Bandwidth optimization - by deleting NULL packets at the source and re-inserting them at the destination.
- Support for high bit rate streams - The RIST Main Profile includes an RTP header extension which increases the sequence number size to 32-bits, and therefore increases the maximum size of retransmission buffers, and thus opens the door for higher bitrate streams, such as lightly compressed (e.g. JPEG 2000, Tico) and uncompressed video.
Contact your Zixi representative to learn more about interoperability testing between Zixi Broadcaster and 3rd party devices. More details about RIST can be found at www.rist.tv
To Create a RIST Output:
- In the Zixi Broadcaster Outputs page, click
. The New output window is displayed.
- Select the RIST option (radio button).
- Type in the unique identifier for this output in the Output Name.
- Select an Input Stream to be made available on this output from the drop-down list.
- Select the Show in Matrix check box to display this stream in the Matrix (see Using the Matrix). Default: Selected.
- Specify the Output parameters (see Output Stream Parameters Table).
- Click OK.
The new RIST Output with its settings is created and now appears on the Outputs screen.
Output Stream Parameters Table
| Parameter | Description |
|---|---|
| Output Parameters | |
| Profile | Select one of the following RIST profiles that matches the input stream:
|
| Type (Main Profile) | Select the stream direction:
|
| Host | Specify the destination IP address or URL of the host to which the steam will be pushed. |
| Port | Specify the target UDP port. |
TTL | Specify the time-to-live (TTL). Used mainly to limit the range (or “scope”) of a multicast transmission. Leaving it as blank uses the default value specified by the operating system. |
Smoothing [mms] | Enables transmission of the output at the correct rate. Required when the receiving device is sensitive and can’t lock on to the stream (in such a case, the recommended latency is 100 - 1000 ms). |
| SMPTE-2022 FEC | In the SMPTE-2022 FEC standard, 1-D and 2-D parity codes are systematic FEC codes of decent complexity that provide protection against bursty or random losses. This setting can be modified without interrupting an existing stream. To enable SMPTE-2022 FEC (Forward Error Correction) select one of the following parity options from the drop-down menu:
|
| Bind to IP | Select from the drop-down list the local IP address to be used for this Input, OR select Any to enable any IP to be used. |
Local Port | Specify from which local port to source the stream, if desired (instead of randomly chosen by the operating system). |
| ReMuxing | Select this checkbox to enable remuxing from VBR MPEG-TS to MPEG-TS CBR (used for professional IRDs). |
| Remux to bitrate [kbps]: | Specify the CBR bitrate to target for a remuxed stream. |
| Buffer Size [ms] | Specify the size of the buffer that will be used for the remixing. A larger buffer increases the quality, but also increases latency. |
| No NULL Packets | Select this option to re-multiplex the stream to CBR but remove the NULL packets in order to maintain low bitrate. |
| Enable Decryption | Select this checkbox to decrypt an encrypted stream. |
Decryption type | If the stream has been encrypted, you can decrypt through the output by selecting this checkbox and specifying the type of ecryption that was used. Select Automatic to decrypt a stream that has been encrypted using Automatic encryption. Only if the stream has not been encrypted, select None (default). Important Notice: if the stream has been encrypted you must decrypt it in the output. |
| Decryption key | If the decryption type includes a key, enter the key to decrypt the stream during output. |
| Enable IFB/Talkback | Select this checkbox to enable IFB/Talkback for one-way communication from the director or assistant director to on-air talent or a remote location. Selecting the checkbox allows the decoder with a Zixi Receiver to send audio back to the encoder with a Zixi Feeder. This offers the ability to, for example, give audio feedback to the camera operator. |
| Port | The port that will be used to send the audio feedback. |