digris EDI/ZMQ bridge

Developed for Opendigitalradio by digris: https://www.digris.ch

This repository contains three useful tools for EDI distribution over ZMQ, TCP and UDP:

• digris-edi2edi
• digris-edimcast2edi
• digris-zmq-converter

DIGRIS-EDI2EDI

Sometimes you want to carry a DAB Ensemble using EDI over the Internet to a device that doesn't support EDI/TCP. Carrying EDI/UDP over the Internet will not work because of burst packet loss.

With DIGRIS-EDI2EDI, you can convert EDI/TCP to EDI/UDP on a small PC that is close to your device. It also allows you buffer the EDI and release it at a controlled point in time depending on the in-band timestamp.

Statistics are made available through a UNIX DGRAM Socket, which also serves as remote control interface.

You can also fan-out an EDI data stream to several destinations.

This tool can be considered to be the successor of ODR-ZMQ2EDI which is distributed as a part of ODR-DabMux.

Remote Control

ODR-EDI2EDI contains a remote-control function that allows changing settings at runtime. Please see ./edi2edi_remote.py for an example on how to use it.

Example:

odr-edi2edi -r /tmp/edi2edi.socket <OTHER OPTIONS>
./edi2edi_remote.py -s /tmp/edi2edi.socket --stats

Statistics

The following stats are available through the remote control interface. Unless mentioned otherwise, they are all 64-bit counters, and all times are in milliseconds.

• num_poll_timeout: Number of times the receive poll timed out for all inputs. Timeout interval: 24ms
• process_uptime: Time since process startup.

Inputs:

• num_connects: Number of times the input reconnected.
• num_late_frames: Number of frames that arrived late (taking into account -w value).
• margin_to_delivery: (not a counter) Margin in milliseconds before frame is too late to be delivered.
• margin: (not a counter) Margin in milliseconds before frame is too late to be modulated.
• connection_uptime: Time since last successful connection established.
• most_recent_connect_error: A string giving the error message of the most recent connection error.
• most_recent_connect_error_timestamp: timestamp (UNIX epoch) of the most recent connection error.

Outputs:

• num_frames: Number of frames sent. Monitor the rate of this statistic to assess if the output is free of interruptions.
• num_dlfc_discontinuities: Number of Frame Counter value errors. Every occurrence of the discontinuity enables backoff.
• num_queue_overruns: Number of times the output queue overruns. This should always stay at zero.
• num_dropped_frames: Number of frames that were dropped either because they were late, or because of backoff. In merge mode, this includes frames that were transmitted from one input but arrived late on another input. Therefore, an increasing num_dropped value does not mean that output frames were actually missing.
• late_score: (not a counter) Score between 0 and 100 indicating how often frames are late.

DIGRIS-EDIMCAST2EDI

This tool can receive unicast and multicast EDI/UDP, and present that to multiple listeneners over TCP.

For satellite reception, it can deframe EDI carried in MPE (see -F option) and GSE (see -G option).

The GSE deframing has been tested with a TBS6903-X PCIe card, and dvbstream -c 0 8192 -i 226.29.3.1 -r 5000 and digris-edimcast2edi -m 226.29.3.1 -p 5000 -b 172.30.201.81 -G 1 -l 8971

DIGRIS-ZMQ-CONVERTER

This tool can act as zmq2edi and zmq2zmq, reading a ZMQ ETI stream from ODR-DabMux and generate an EDI or ZMQ stream.

Installation

Requirements:

• A C++17 compiler

• autotools (debian packets build-essential automake libtool)

• libzmq (debian packet libzmq3-dev)

  ./bootstrap.sh ./configure make sudo make install

Licence

See the files LICENCE and COPYING

Contributions and Contact

Contributions to this tool are welcome, you can reach users and developers through the ODR-mmbTools group or any other channels mentioned on the ODR website.