Providing subtitles and transcripts for your videos makes them accessible to hearing-impaired viewers, makes understanding the content easier for non-native speakers, and enhances discoverability of your content by revealing it to search engines such as Google. While YouTube makes system-generated subtitles available on some videos, the quality of these subtitles is extremely low and will not meet the needs described above.
Note: Lecture transcriptions created for hearing-impaired students during a course are generally not made available for use as part of a video. For more information, see accessibility.
There is currently no MIT service for automatic subtitling and transcribing, however we expect to offer one soon through TechTV.
An ongoing project available for experimentation is SpokenMedia, an umbrella project for the development of tools and services to enable rich media notebooks for learning and teaching. SpokenMedia focuses on automatically creating a text transcript from lecture video (with potential integration in larger media production workflows), a video player with a video-linked transcript (and other interactive features), and a transcript editor.
Many programs are available to create and synchronize subtitles manually. These options work well for videos under ten minutes in duration; manually creating subtitles for an entire lecture will be time consuming.
Universal Subtitles provides free, open tools for creating and reviewing subtitles - collaboratively or on your own.
Video transcription is a large and growing business, and many companies will be happy to transcribe and subtitle your videos for a (sometimes substantial) fee. OCW has worked with 3Play Media to transcribe and subtitle some of their videos.