Timed text files are an important media element for any application or video platform. They enable accessibility to end users who are deaf, hard of hearing, or require translation to a different language. This article outlines the variety of timed text files supported in dotstudioPRO.
Kinds of Timed Text Files
There are three kinds of timed text file. Within the dotstudioPRO ecosystem, "kind" means whether a timed text file contains translation or transcription data.
dotstudioPRO is able to support three kinds of timed text file: Closed Captions, Subtitles, and SDH, however not kinds may be supported or even passed to all endpoints.
| Kind | Description |
|
Closed Captions (CC or captions) |
Closed caption files transcribe dialogue and provide descriptions of sound effects and music for end users who are deaf or hard of hearing. Good closed captions often indicate which performer is speaking during scenes with multiple speakers. Closed captions are required for nearly all video broadcasts in the US, under FCC regulation. Generally, closed captions files are provided as a sidecar file. In some cases they are embedded into the video file as a separate data stream. Proper closed captions files never include translations. |
|
Subtitles (subs) |
Subtitle files translate dialogue and text on screen from one language to another. Descriptions of sound effects, music, and speaker identification should not appear in subtitle files. Subtitle files can be provided as sidecar files or burned directly into the video pixels. Burned-in subtitles can be easily combined with Closed Captions; burn-ins may not be accepted by all platforms as they cannot be removed. |
| SDH |
SDH means "subtitles for the deaf and hard of hearing." They are a blended file, providing both transcription and translation data in a single file. If a single timed text file provides translation of another language as well as any descriptions of music, sound effects, or same language dialogue, it is considered an SDH file. SDH is often ideal in movies with multiple spoken languages or for delivery to platforms that explicitly request it. SDH files can be provided as sidecar files, but should never be burned-in to a video file. |
Supported Languages
dotstudioPRO supports a number of languages. These values match across ingest and output. Note that all languages may not be supported by all endpoints; for example, some platforms may only support "Spanish" as opposed to "Latin American Spanish."
In all language drop downs, languages are sorted first by the most used languages, then alphabetically.
Most Used Languages:
English, Spanish, Latin American Spanish, French, German, Italian, Japanese, Cantonese, Mandarin, Hindi, Russian
Additional Supported Languages:
Afrikaans, Amharic, Arabic, Armenian, Assamese, Azerbaijani, Bengali, Burmese, Chinese Unspecified, Czech, Danish, Dutch, Esperanto, Finnish, Greek, Gujarati, Hausa, Hebrew, Hungarian, Icelandic, Igbo, Indonesian, Javanese, Kannada, Kazakh, Khmer, Kinyarwanda, Korean, Kurdish, Latin, Malay, Marathi, Nepali, Norwegian, Persian, Polish, Portuguese, Punjabi, Romanian, Sindhi, Sinhala, Somali, Sotho, Sundanese, Swahili, Swedish, Tagalog, Tamil, Telugu, Thai, Turkish, Ukrainian, Urdu, Uzbek, Vietnamese, Welsh, Xhosa, Yiddish, Yoruba, Zulu
Supported File Types
dotstudioPRO supports two types of file extension: SRT and VTT. It is recommended that both are provided whenever possible, as platforms may have specific filetype requirements for delivery and publishing.
dotstudioPRO does not support timed text files with SCC, CAP, TXT, or STL extensions.
| File Type | Description |
| SRT |
Originally a human-readable subtitle format. SRT files contain no positional information and do not support any text formatting. They were adapted to become the internet standard for all timed-text files as fractional seconds are expressed in milliseconds instead of frames. SRT files are supported by most VOD platforms. |
| VTT |
VTT files are the standard generally associated with HLS video streaming. The files are human readable, and look almost identical to SRT files, however text formatting and positional information are fully supported. VTT files can be automatically generated by dotstudioPRO, if only SRT are available. VTT files are not supported as widely as SRT, but are required for creating embedded HLS files. |
Ingest Methods
The below tables outline how timed text files are ingested into dotstudioPRO.
| Ingest Method | Supported |
| Direct Upload | Kind, Type, Language, and multiple file ingest supported supported after video files have finished transcoding. |
| MRSS Ingest | Kind, Type, Language, and multiple file ingest supported. |
| CSV Ingest | Kind, Type, Language, and up to 5 timed text file ingest supported. |
| Custom Integrations |
Consult your DSP sales rep. |
During ingest, timed text files must be assigned a valid language and kind value. Files provided with an invalid extension or language value will be ignored/rejected. If an invalid/blank kind value is provided, dotstudioPRO attempt to automatically assign a kind value:
- If timed text language = video language set as “Closed Captions”
- If timed text language does not equal video language, set as “Subtitles”
- If no video language value is available, set as “Closed Captions”
Only one file per kind/language/type combination is supported per video in dotstudioPRO. To replace a timed text file on your dashboard, you will need to delete the old timed text file and then upload the new one.
Outputs
Not all files are supported by all platforms. Each MRSS feed, P2P transfer, or app output generally falls into three categories:
- Provide ALL timed text files available.
- Provide one timed text file per language.
- Provide one timed text file.
- Provide NO timed text files.
When only a single timed text file can be provided, they are prioritized using the below waterfall:
- If only one timed-text file exists, furnish regardless of kind or language.
- [video language] SDH.
- [video language] Closed Captions.
- [video language] Subtitles.
- English SDH.
- English Subtitles.
- English Closed Captions.
- The first available SDH file.
- The first available Subtitle file.
- Any other file.
This table outlines how timed text files are furnished to various DSP outputs:
| Files Furnished | App Players | MRSS Feeds | P2P Transfers |
| All TT Files | Android, AndroidTV, AppleTV, FireTV, IOS, Roku | dotstudioPRO, Internal Syndication, Local Now, Glewed, Samsung, Streann, Stirr | |
| One TT Per Language | Vizio | Frequency, Nimbus, Amagi, Xumo, | |
| One TT File | Wurl | Local Now (VTT), Crackle (SRT), TubiTV (SRT), Video Elephant (SRT) | |
| None | Generic Video-Only, ZoneTV, Jio, Zeasn, Comcast | ||
| Other | PlutoTV - All SDH/Captions files. Subtitles are not sent. (VTT). | The Roku Channel - one SDH/Captions file matching video language. All subtitles are sent. (VTT). PlutoTV - one SDH/Captions file matching video language. All subtitles are sent. (VTT). |
Updated