Overview
The Kaltura Player supports rendering subtitles and closed captions in VOD and live content.
Captions are a text version of the dialog and other sound content of the video. Subtitles are text versions of the video’s dialog and are used to translate the dialog into other languages.
Kaltura REACH offers human captions, automatic captions, transcription, translation, and enrichment services including audio description, chaptering, in-video, and cross-library search and discovery, deep-linking capabilities, metadata, and keyword extraction. To learn more, read our Kaltura REACH articles.
Features
Viewers can select and toggle between different captions, subtitles and audio description. Captions, subtitles and audio description are fully searchable as a metadata field. Kaltura’s accessibility player plugin also makes the captions readable via screen readers and therefore helps organizations adhere to VPAT compliancy regulations. Kaltura’s “In Video Search” API allows users to look for a specific phrase within a library of videos and within the search results, and directs the user to the exact point in the video where the phrase appears.
- Captions language
- Audio tracks - Setting up Multi Audio for VoD requires a custom transcoding flavor. This is done by PS and needs to be scoped.
- Audio description
- Captions styling
- Captions position - captions can be positioned statically in an exact location, or dynamically so that captions move up when something is shown on the bottom of the screen. This is relevant both for the Web (HTML5) player and the native SDK players (Android and iOS).
- Transcript - displays captions on a VOD when available. The Transcript widget may be added to the player to display the captions file in a transcription window alongside the player. It provides the capability of searching and jumping to specific times when a word was spoken.
- Navigation - when captions on a VOD are available, you may use the magnifying glass on the video you are watching to search for certain text in the captions.
Setup
To learn how to set the Captions default display on the player, see The Kaltura Player Studio Admin Guide - Player Settings.
User Interface
Captions, audio tracks and AD
If a video has captions, multi-audio tracks or audio description, the menus are added to the settings
menu to allow the user to navigate between languages and turn off features. In addition, if a video has captions, a toggle CC button will appear on the bottom bar to allow the user to instantly show or hide default captions. The user can use the captions sub menu within the settings menu to select different caption languages, in case those are available.
The administrator can also choose whether to have captions display on the player by default when the user starts playing the video.
Captions Styling
Select the Advanced captions settings to open the Communications and Video Accessibility Act (CVAA) screen. By default, there are 3 options for captions styling. After a user defines a custom style for the captions, it is added to the default styles available on the main CVAA screen.
Advanced Captions Settings Samples
Note: When using the Safari browser to play content, switching to full-screen playback is handled by the native player. In such a case, caption styling is no longer effective.
Caption support
The Kaltura V7 Player supports several types of captions/subtitle formats, both in-band (part of the streaming manifest itself), or out-of-band (using an external file).
The following caption types are supported:
| Caption Format | Description |
|---|---|
WebVtt (.vtt) | This is the most common format used for online video. WebVtt captions can be embedded as part of the stream or be side-loaded as a separate file. |
SubRip Text (.srt) | SubRip File Format (SRT) is a common format used for online video. SRT files include only the captions without any metadata. |
SMPTE-TT | A common format that supports DVB subtitles, which are common in live liner streams, as well as image-based or character-based captions which are embedded in the stream. SMPTE-TT is supported by the DASH streaming format. |
