The Complete Guide to Caption Encoders

When it comes to live captioning, the very first step is determining if you will need an encoder. Encoders let a broadcaster simultaneously receive and encode the captions, allowing them to be displayed alongside a television program or video in real time. Let’s clear up some of the unknowns around encoders and see which option would be best for you.

Encoders have been around for decades, but the first big steps in modern encoder technology occurred in 1993, when the FCC mandated that TVs include a decoder to receive caption signals, thus allowing a viewer to turn captions on or off on their television (tip: “closed captions” means a viewer is able to toggle on/off the captions, whereas “open captions” are always on). The caption encoder is the piece of equipment (or software) a network uses to pair the captions with the video and audio stream. Captions are encoded during broadcast and then decoded when they reach each individual TV.

Now, you may ask: “Do I need an encoder?”

In order to know if you need an encoder, you’ll have to answer the following:

  • Is my program going straight to broadcast or cable?
  • Am I streaming my live program on Facebook or YouTube?
  • Does my platform require live captions to be embedded in the stream as 608/708 data to display them?

If you answered yes to any of the above questions, read on. (Or, if you’re uncertain, contact us at Captionmax).

Just as the equipment to receive captions on our televisions and live streaming platforms has changed drastically, the technology Captionmax uses to encode and send captions has also advanced. For instance, Captionmax’s proprietary Rocket™ system allows us to manage and transmit caption data to and from a variety of sources, empowering us to provide the best quality captions across multiple platforms. Captionmax will also monitor and manage all the traffic so your confidential information for equipment connection is preserved.

Encoder Workflows

In general terms, there are three types of encoder connections: Telco (analog/modem), telnet (digital/IP), and iCap (only if the encoder is manufactured by EEG). And, as more broadcast companies are pivoting towards online streaming, virtual encoders are a growing technology.

The workflow of most encoders are similar:

1: A caption provider transmits a caption feed to the encoder(s).
2: The encoder collects the caption feed for transmission to the viewer.
3: The encoder pairs the captions to the video on a specific data transmission line, known as line 21– this is the data that televisions are mandated to decode captions from.

The path of captions from our writers here at Captionmax can be simplified like this: 

A standard captioning path workflow. Our captioner uses captioning software to live caption your content, which is then transmitted to the client encoder. This is then sent to the television broadcast, allowing your TV to decode the captions.

Here at Captionmax, our Rocket system has the ability to connect to all types of encoders, but each one requires slightly different information. Additionally, some encoders have the ability to be connected to in different ways. You will need to refer to the manufacturer’s guidelines on how to set up your own, as well as which setting is most efficient with your broadcast workflow. Because of this, our Rocket system’s connection flow looks slightly more complicated at first blush. Don’t worry, our crack team of realtime technicians will certainly help simplify the process! 

The typical workflow path of live captions using our proprietary Rocket technology. Our caption writer creates the caption with captioning software, which is then sent to the client encoders using our Rocket technology and a connection code. Our system can connect to multiple client encoders at once! These encoded captions are sent to the television broadcast and passed along to your TV, where the captions are decoded and displayed.

Telco Encoders

Even though it’s based on older technology, many clients still stand by dial-up telco encoders. A telco encoder requires phone lines to connect to. Our Rocket System uses dial-out modem cards to connect our writers through Rocket to the encoder’s modem. Just like your old dial-up internet, it is all possible thanks to that old familiar sound of dying robots. The screeching, clicking, and buzzing is actually the two modems discussing how to best communicate. Our dial-out modems are capable of a wide range of settings so that we can best work with each encoder. In order to best set these up, our technicians will need the phone number to dial in order to connect with the encoder’s modem. To get an audio feed and follow along in time with what is being captioned, any caption writers will need audio for the broadcast routed to an audio coupler.

The information we need typically looks like this –

Encoder: 651-500-4280
Audio coupler: 651-500-4281

We input the encoder’s information into our Rocket system prior to connecting and testing, so getting this set and tested in advance is extremely helpful.

Telnet Encoders

A telnet encoder uses an IP and port number to receive the caption data. Similar to a telco encoder, we also need a separate audio line to hear the dialog we are meant to be captioning. While connections are now almost instantaneous (no more whirring modems!), this does require extra checks and tests as different network security protocols can block incoming or outgoing caption data. This step is made much easier if you whitelist Captionmax before the event. A bonus to this type of encoder is that phone lines don’t need to be run into the encoder; an internet connection (ethernet) is typically required.

The information we need typically looks like this –

Port: 23
Audio coupler: 651-500-4281

We input the IP and port into the Rocket system and can test almost immediately. Because our caption data comes from one particular IP, it may need to be whitelisted on a client’s network in order for us to connect to their encoder.

iCap Encoders

An iCap-enabled encoder is manufactured by EEG, and with their direction, you can set up the encoder to feed both audio and video to our captioner, making it easier to monitor and caption effectively. These EEG-manufactured encoders have iCap software for improved functionality, such as sending audio to the captioner, but can also be set up as IP connections if desired. The video and audio are converted to a data stream on the iCap cloud which is accessible via an Access Code. Captions are routed through the cloud and into the encoder where it is married to the stream and ready for broadcast. These encoders can be bought or rented for any type of event or broadcast.

The information we need typically looks like this –

Access Code: TV2021

In order to expedite the connection process, you may need to add Captionmax as an approved vendor. Once the code is created on the iCap cloud, you provide Captionmax with agency access, and we’re able to connect and hear audio!

Virtual Encoders

There are various virtual encoder options available, and they function similarly to physical encoders without the physical box and connection. They are hosted in the cloud and require clients to connect their stream digitally. For instance, EEG offers iCap Falcon which functions similar to a normal EEG encoder, but all hosted within the iCap cloud. Virtual encoders are useful for events that are streamed online, where the virtual encoder will add the closed captioning data and reroute the video stream, now with captions, to the desired platform such as YouTube, Facebook, or Vimeo. They are also a useful option for singular events that don’t necessitate the purchase of permanent equipment.

Encoder Alternatives

Encoders are the industry standard for including captions with broadcast streams, but as the times change there is less reason to keep physical equipment for digital streaming only. Not all streaming platforms natively support sidecar caption files, necessitating at least virtual encoders to pair caption data to a webinar or online stream. Sometimes the extra effort to include captions within the stream itself is not necessary and captions can be included as a separate entity. With improved visibility towards media accessibility, some applications are now building caption functionality directly into the players. This is true of programs like Zoom, Webex, Adobe Connect, and YouTube. Captionmax is also able to offer an HTTPS website of a closed captioning session with customization such as users’ ability to change font, colors, and size. This opens opportunities for any event to have a means for closed captioning solutions.

The world of encoders can be a complex process all made to simplify how we deliver quality captions to your broadcast. Whether you choose telco, telnet, iCap, or virtual encoding, you’ll be delivering your now-accessible media content to an eager audience, ready to perfectly understand your message.