Understanding closed captions’ functionality can significantly enhance your next video’s performance metrics. Contrary to popular belief, subtitles are not solely intended for viewers with hearing impairments. In fact, millions of non-hearing-impaired individuals in the United States also rely on subtitles, emphasizing their widespread usage and the importance of incorporating them in your videos.
Including subtitles has shown countless benefits for content creators. For example, according to one study, closed captions can increase Facebook viewing time by 12%.
To fully utilize subtitles, it is essential to familiarize yourself with the different caption formats available. This knowledge will empower you to make the most of subtitles and leverage their benefits effectively.
This comprehensive guide will provide an overview of the most common closed caption file types you should know. By understanding these formats, you will be equipped with the necessary information to optimize your use of subtitles in your videos.
6 Caption Formats and Their Use Cases
Every platform can set its rules on subtitle formatting. With every video upload, your captions must be in the correct subtitles format for them to work. Different platforms won’t automatically convert your subtitle file.
So, what are the most common caption files in use today?
SRT
SRT files are the most common type of subtitle format used by video, social media, and software platforms. Otherwise known as a SubRip Subtitle file, the SRT format has attained tremendous popularity because it’s nothing more than a plain-text file.
Without additional styling, this file contains only the critical information needed to show your subtitles, including the text and timestamps. Most creators will create these subtitles within a plain-text editor like Notepad or TextEdit.
If you’re searching for the most basic type of subtitle file, SRT is the right choice for you because these files are compatible with platforms like:
- YouTube
- Vimeo
- Netflix
- Amazon
Editing your SRT file can be done by returning to your plain-text file or using a third-party editor to make necessary changes.
WebVTT
WebVTT subtitle files, or Web Video Text Track files, are a popular subtitle format created in 2010 by the Web Hypertext Application Technology Working Group (WHATWG).
Since this caption file format is based on SRT and even used the same file extension in the early days, WebVTT was once known as WebSRT. So, why would you use this format with all of the similarities of WebVTT?
- WebVTT allows for the inclusion of description and metadata information within the frames.
- Cue identifiers are optional.
- These files can support additional information, including frame placement.
In many ways, WebVTT takes what SRT created and advances it as part of the HTML5 revolution. This is why it’s commonly used on platforms like YouTube, VIMEO, and Video.js.
DFXP/XML
Studies have shown that 54% of consumers want more accessible, quality video content from the brands they love. One option for enhancing the quality of your videos and sharing your message is to use DFXP/XML subtitles.
DFXP stands for Distribution Format Exchange Profile and is the standardized way of delivering XML captions. This type of captioning is delivered via a special .dfxp file and works with several major video platforms and applications.
Alongside YouTube, Vimeo, and Netflix, DFXP files are compatible with several applications, including all Adobe products and Microsoft Silverlight.
You will find information similar to the SRT file format within these files. The critical difference is that DFXP files contain information about form captions formatting and location specifications. Unsurprisingly, this makes these subtitle files more complex.
SCC
SCC format is one of the oldest forms of subtitling because it was primarily used within broadcast television. Scenarist Closed Caption (SCC) files held CEA-608 captioning data in 29.97 drop (DF) and non-drop frame rates for years. Initially, they were designed for analog television, VHS, and DVDs.
With the death of broadcast television, one would assume that SCC captions would disappear forever, but this isn’t the case. The versatility of SCC files has brought them to modern platforms like iTunes, Amazon, and Netflix. Additionally, they are often used as sidecars in video editing programs, including Microsoft Visual SourceSafe and Adobe Captivate.
So, why would SCC files be of any use to creators?
Simply put, they perform exceptionally when incorporating broad stylistic elements, including screen positioning, italics, and musical notes. Even today, the stylistic captioning features of SCC files make them a critical piece of the puzzle in complying with FCC requirements.
iTT
Apple is notorious for its strict standards regarding the content it allows onto its platforms. This is why the iTunes platform only supports three different caption formats, including SCC and DFXP.
iTT stands for iTunes Timed Text and is the native Apple format for delivering caption content within the iTunes Store. Like other formats on this list, you can choose from various color, placement, and formatting options when using iTT files.
However, what makes iTT stand out from other options is its ability to support non-Roman characters. This is why content from Asian countries is often presented with an iTT file because other more common subtitle formats cannot handle Unicode character sets from other world alphabets.
STL
STL stands for “Spruce Subtitle File” and was developed by Spurce Technologies for DVD Studio Pro software. However, it has found extensive usage within broadcast television. Production operations prefer to use it for closed captions in television and film.
These highly professional subtitles use special encoding, meaning STL files cannot be edited within basic programs like Notepad. For this reason, STL files are only compatible with a select few platforms.
How to Choose the Right Caption Formats
Subtitle formats can have distinct yet overlapping characteristics, making it challenging to determine the ideal file type for your needs. As a result, many content creators opt for SRT files when adding subtitles to their videos due to their simplicity and ease of use. This straightforward format is often the preferred choice for its user-friendly nature.
While SRT files are compatible with most platforms, you may not extract the most potential from closed captioning by going down this route.
If you’re concerned about using caption files, here’s a cheat sheet to help you understand which platforms accept which formats.
Social Media Formats
- Facebook – SRT/WebVTT compatible
- Instagram – Automated captioning
- Twitter – SRT/WebVTT compatible
- LinkedIn – SRT/WebVTT compatible
- TikTok – Manual captioning
Video Platform Formats
- YouTube – SRT, WebVTT, SCC, and more
- Vimeo – SRT, WebVTT, SCC, DFXP, and more
- Dailymotion – SRT
- BrightCove – WebVTT
Application
In selecting the correct format, you also have to study the specifications of your video and the functionality the end user expects.
Technically, while there are more than 25 possible subtitle formats worldwide, SRT and WebVTT will support most projects. In many cases, these formats may be used interchangeably.
Before deciding which one will work best for you, here are some questions to ask yourself:
Is the subtitle format set for you?
Sometimes, a platform may not give you a choice. For example, some social media platforms will not support WebVTT, meaning you are already locked into using SRT. Likewise, some platforms may not support SRT.
For example, the eLearning platform Articulate 360 offers no support for SRT but will allow you to import WebVTT.
Do I need font styling and positioning?
If you need extra font styling, such as color, to make your content more accessible, WebVTT is the only option available.
SRT cannot incorporate any advanced styling and positioning features because it’s the most basic subtitle format.
Do I need extra metadata?
Some creators may require metadata for captioning. In this case, WebVTT is the best choice because SRT doesn’t support the addition of metadata.
Add Subtitles to Videos in Minutes with Sonix
Understanding captions and their formats is far from straightforward because there are so many. But regardless of which format you require for your next video project, Sonix AI can help you add subtitles to videos in minutes, ready for conversion into SRT and WebVTT formats.Discover why so many businesses and individual content creators rely on us to generate highly accurate captions at a fraction of the time and cost by trying Sonix for free today.
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