Creating Subtitles and Captions In-house with DIY Software

Contributed by Giovanni Galvez, Product Manager of Subtitling and Captioning for Telestream

While subtitling and captioning has long been thought of as a TV mandate, especially in the United States, today it’s becoming essential for worldwide distribution.

Not only do subtitles and captions make a video program more accessible to the millions of deaf and hard of hearing people around the world, it expands the market for that content. Video with the subtitles and captions displayed can also be enjoyed by those watching a show without headphones in public places, such as airports, bars, gyms and hospitals, where the sound might disturb others.

Adding captions and subtitles to OTT video delivery is the gateway to dramatically expanding your online audience. According to Google, on average, two-thirds of a channel’s views come from outside its home country. 80% of YouTube’s views are from outside of the U.S. and YouTube has launched local versions in more than 88 countries. Netflix reports having subscribers in 130 countries as of January 2016 with one of the biggest markets being Latin America with over 5 million as of Q1 2015.

By law, U.S. broadcasters must have captions on broadcasted content that is subsequently made available to Internet and mobile viewers. And Over-the-Top (OTT) service providers, such as iTunes and Netflix, increasingly require closed captioning and subtitling on the video programs they offer. U.S. laws protecting the rights of the deaf and hard of hearing even require closed captioning on public service videos, such as online educational programs and announcements.  More recently, as a result of its “Let’s Talk TV” initiative, the CRTC in Canada also expressed the expectation that closed captioning will extend beyond the traditional broadcasting platforms to include online broadcasting.  This initiative will improve access to video content for Canadians with disabilities.


At a time when international distribution is a very appealing way to broaden the market for video content, subtitling provides an on-screen foreign language translation that makes the show accessible to those that don’t speak the language the show was produced in.

Given the growing need to deliver video programs for multiple platforms and markets—and the growing volume of media to be captioned—today’s digital content creators have a pressing need for DIY (Do-It-Yourself) captioning software that gives independent producers and other content creators the means of creating, editing, repurposing and outputting their own closed captions and subtitles in-house.

Broadcasters and content creators need a simplified, automated, and streamlined solution for adding captions and subtitles to programming that relegates much of the technical complexity to a background process. There’s also a growing need for software that offers a user-friendly interface to make the process as easy as editing with a word processor —or using graphical icons and other intuitive on-screen tools—as well as support for the myriad of video and caption file formats in use today.

For live programming, of course, there’s no getting around the need for highly specialized, third party closed caption service providers that can generate closed captions on the fly for a premium. But for non-live pre-recorded shows, having powerful, affordable captioning tools readily available in the postproduction and automated media processing workflow can save significant time and money.

For international content creators that want to include the U.S. market in their video distribution strategy, it’s important to understand that the U.S. has arguably the strictest laws, regulations and rules governing the creation and use of closed captions in the world. Not only must video programs have closed captions on them when they air, the FCC now says those captions must go above and beyond to ensure an optimal viewing experience.

Under these new quality rules, captions must be accurate, with no misspellings or errors, and appear on-screen in sync with the spoken dialogue and audible sounds. They must also run throughout the entire show without blocking any important on-screen visual information, such as lower third supers, maps, illustrations, full-screen graphics, keys, and other visual elements.

Creating captions that comply with U.S. laws and regulations is essential to avoiding potentially large fines and penalties. An investment in in-house DIY captioning and subtitling software can pay for itself quickly by avoiding just one hefty fine. And by streamlining the technical process, the software can also save money, which also offsets the cost.

To create your own closed captions and subtitles in-house, it’s best to start by developing an accurate transcript of the audio portion of the video program that requires accessibility. If the spoken dialogue has already been typed out for input into a teleprompter, the captioner can save time and effort by using that teleprompter copy as a springboard for the captioning and subtitling process.

If lead-time allows, and captioners don’t want to prepare their own transcripts, they can consider sending their audio files—in proxy file formats like MP3, MP4 and AVC—to a third-party transcription service that take care of it for a fee.

To marry the transcript and video together, look for software that is capable of comparing the words on the transcript with the audio portion of the video to help sync the two together. DIY captioners want a software solution that offers an end-to-end workflow that automates the process of importing the desired transcript and video, synchronizing the captions, and encoding the captions right into the video deliverable.

For bi-lingual and multi-lingual scenarios, such as distribution to international markets, Telestream’s CaptionMaker and MacCaption—DIY closed captioning software—has a unique capability called Multi-language Merge that makes it easier to work with translators to create foreign language captions and subtitles that are fully compliant and in sync with the video. This method is very innovative because the captioner doesn’t need to speak the foreign language they want to use, and the translator doesn’t need to know anything about captioning or subtitling.

One of the greatest advantages to the DIY approach for subtitling is that content creators can control the look, fonts and style of their captions and subtitles. The software allows users to customize margins, resolutions and burn-in overlay subtitle graphics into media to  provide the desired look of on-screen subtitles.

The presentation of the captions and subtitles goes beyond just choosing the font styles. There are some industry best practices that must be followed to ensure a consistent, familiar on-screen presentation that caption users will readily understand. For example, speakers and other on-screen talent must be identified in a consistent way, and their comments must appear in the same place on-screen regardless of how they move around the scene or show.

Other rules are that multi-line captions should be left aligned, new sentences should start on a new line, and there shouldn’t be a line break between a person’s name and title or after a conjunction. For more about style rules, and how to properly preserve the intent of the dialogue, check out the Captioning Key, an industry-approved style manual published by the Described and Captioned Media Program (and downloadable at

So whether the target market is traditional HDTV/SDTV broadcasting, including compliance with the CEA 708/CEA 608 specification for North America, OP-47 Teletext for Australia, burn-in subtitle overlay —or Internet and mobile delivery for iTunes, YouTube, Netflix, and social media—having affordable, user-friendly DIY captioning/subtitling tools like CaptionMaker and MacCaption can save considerable time and money by ensuring legal compliance, expanding accessibility and ensuring an optimal viewer experience.


About Giovanni Galvez

gio-biopicture-jpg Giovanni Galvez, Product Manager for Telestream captioning products, has spent a decade in the closed captioning software industry helping broadcasters migrate their closed captioning to a file-based workflow, and helping government agencies add closed captioning to web videos.  He helped develop the first software to convert TV closed captioning CEA-608 to SMPTE TTML file format for the web, and in January 2016, his team received a National Emmy Award for Technology and Engineering on ‘Standardization and Pioneering Development of Non-Live Broadband Captioning’.

Galvez is a frequent presenter at video industry and accessibility seminars, discussing new and essential file-based alternatives for HD closed captioning that integrate with non-linear editing systems, broadcast servers, and internet video delivery platforms.



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