YouTube Caption Tools Part 2

This week I'm at the AHEAD conference, and Sean Keegan, Jayme Johnson, Ken Petri and I have teamed up for four presentations on video accessibility, including an all-day pre-conference session. I also gave a national webinar on Tuesday, live from my hotel room, on this same topic.

Several people at the conference (directors and staff of higher education disability services offices) have asked specifically about captioning YouTube videos. The need they're describing is this: Faculty members are supplementing their courses with materials from YouTube, resulting in the need to caption those videos as an accommodation for deaf students. Only the owner of a YouTube video can upload captions, so even if the college or university were to caption the video themselves, they would need to send the caption file to the owner, hope the owner checks their YouTube inbox, and persuade the owner to upload the caption file. There are plenty of success stories with this approach, but there are also plenty of stories of YouTube owners never responding to these requests.

In response to the folks who described this need, I thought I'd revisit some of the free online captioning tools described in my earlier blog post Free Tools for Captioning YouTube Videos, and see if one or more of them might provide a solution. Perhaps they could help not only with the captioning process, but also as a means of delivering a captioned video to students who need this accommodation. The ideal tool would have these characteristics:

  1. Accepts a YouTube URL as a video source.
  2. Provides an easy-to-use interface for captioning the video.
  3. Provides a permanent link by which others (i.e., the student) can access the video.
  4. Optionally, the permanent link could be made private, since some institutions might be concerned about the legality of providing a publicly viewable captioned version of someone else's video.
  5. Ideally, the tool itself should be accessible.

With these criteria in mind, I took a fresh look at, Subtitle Horse, CaptionTube, and another tool that I hadn't reported on previously but have since grown to like a lot, Universal Subtitles.

Below is a summary of how these tools compare on specific criteria, some of which are relevant to the need at hand, and some of which I'm documenting just because I have the opportunity, and I figure folks might be interested.

YouTube As Video Source

All four tools accept YouTube URLs as video source. Universal Subtitles is the only tool that supports the new short URL that YouTube offers when you select "Share" beneath a YouTube video. This URL has the format:

Other tools haven't updated their parser to support that, but they all support URLs in this format:

Other Video Sources

  • CaptionTube supports only YouTube URLs. Period.
  • DotSub claims to support "all digital file formats up to 700 mb". It's the only tool that supports users uploading video directly to their servers. It's also the only tool that requires users to wait (typically several minutes, depending on the length of the video) while it processes the video. This is true not only of uploaded video, but also of YouTube URLs. All other tools take a few short seconds to parse the YouTube URL, then they're all set and ready for captioning, or if something went wrong you get an immediate error. With DotSub you have to wait around for an email telling you whether the processing was successful.
  • SubTitle Horse supports URLS that point either to YouTube videos, or directly to FLV, and MP4 files anywhere on the Web.
  • Universal Subtitles supports URLs that point directly to Ogg, WebM, FLV, or MP4 files, as well as YouTube, Vimeo, Blip, and Dailymotion URLs. This is the only tool that supports the latter three.

Ease of Use

In my original blog post on this topic, I ended up favoring dotSUB over all the other tools, primarily for its keyboard model. All tools support basic transcription functions via keyboard shortcuts, which is important for getting into a steady flow and transcribing video efficiently. Proof that it's sometimes the simple things that matter, dotSUB is the only tool that displays the keyboard shortcuts on the screen at all times. That's one less thing in life to commit to memory, and I really appreciate it. SubTitle Horse also displays keyboard shortcuts, but you have to scroll to see them all.

One things I've grown to not like about dotSUB is the militant way it handles overlapping caption times. The following screen shot demonstrates this problem.

Screen shot of DotSub caption grid. The second caption ends at 0:07, and the third caption starts at 0:06, which results in an error.

When editing captions, you sometimes need to change the start time to an earlier time. This often results in a collision with the previous caption, and dotSub throws up an error "This item overlaps with another" and prevents you from saving the changes until you've entered a valid time. I would prefer that dotSub honor my request to change the start time, and automatically adjust the previous caption's end time so there is no overlap. That's what Subtitle Horse does.

Universal Subtitles rocks. It has three modes for typing captions. The coolest of these is called "magical autopause". You just type, and it pauses when it thinks you need it, and resumes playing when it thinks you don't. This takes some getting used to, but once you do you can caption a video lickity split. You don't have to remember any keystrokes - just type! If you prefer controlling the pause and play functionality yourself, you can do that too, by pressing the tab key (or shift+tab to rewind eight seconds). Time syncing is a separate step, performed by watching the video and pressing down arrow whenever the next caption should appear. Then, to adjust timing you can drag the caption text along a timeline. This is all very intuitive, maybe even fun!

Universal Subtitles screen shot

CaptionTube sucks. I remember thinking that the first time I blogged about it, but I couldn't remember why I felt that way. Now that I've given it a second look, I still have the same reaction. So, I stand behind what I said before. Actually, there is one potentially good thing about CaptionTube: It does a better job than all the others at utilizing the YouTube Data API. Users log in with their Google ID and have direct access to their own YouTube videos, and theoretically can even save their caption files directly to YouTube, whereas all other tools require you to download the caption file, then upload it back to YouTube. That's not a huge problem, but it's inefficient. I say that CaptionTube "theoretically" supports this because I only saw this option once when I tried to "Publish" my captions. Despite a vigorous search I could never get that option to appear again. CaptionTube does have "Beta" next to its logo, so maybe this tool will improve with age.

Sharing Captioned Videos With Students

  • CaptionTube does not seem to have a means of sharing videos.
  • DotSub is the only tool that allows videos to be set to private and shared with individual designated users.
  • Subtitle Horse does not have user accounts, and does not save captions. It's designed solely for captioning videos in a single session, then downloading a caption file.
  • Universal Subtitles provides a permanent link for all videos, but all videos are public.


Each of these tools has a form field in which captions are entered, and hotkeys for controlling the player and performing most transcription-related functions. Therefore, if a user can navigate to that form field and give it focus, they can caption a video. That said, navigating to the form field is no trivial task without a mouse or using a screen reader. And the subsequent steps in the workflow (e.g., editing captions, adjusting timing, exporting the results) could be daunting challenges for some users. None of these tools was developed with accessibility in mind.


To provide students access to captioned versions of YouTube videos, assuming YouTube isn't an option, one could use either dotSUB or Universal Subtitles. If it's important that the captioned video not be displayed publicly, dotSUB is the only choice. If you prefer the ease of use of another tool (Universal Subtitles or Subtitle Horse) you could use those tools to caption the video, then download the caption file and upload it to dotSUB. All tools export to SRT caption file format (Subtitle Horse also exports to W3C Timed Text), and dotSUB supports importing SRT files.

9 comments on “YouTube Caption Tools Part 2

  1. Hi Terrill,

    Thanks so much for including us (Universal Subtitles) in your review.

    I thought it was worth noting that you can upload a text transcript, SRT, or number of other formats, to any Universal Subtitles video. The "upload subtitles" option lives in the lower left corner of the video's Usubs page. We'll be making it more obvious soon.

    And of course we're very open to suggestions and feedback. Feel free to contact me at dean at


    PS. I have family that lives right outside of Fairhaven!

  2. @Dean - Thanks for your good work, and for the note about uploading a transcript or caption file to Universal Subtitles. For completeness, that functionality is also supported by Subtitle Horse and DotSub (the latter of which I mentioned in the Conclusion), but not by CaptionTube. As for suggestions and feedback, thanks - I'll be in touch!

    @Norman, I'm aware of OpenCaps but I hadn't played with it. As I understand it, it was created by folks at the Adaptive Technology Resource Centre with the intent of creating an online version of CapScribe, their downloadable captioning application for Mac. I like CapScribe, and am particularly interested in how that tool addresses the need for audio description in addition to captions. However, I'm looking at the online demo of OpenCaps now and it seems to me that it still has a long way to go.

    Also, it doesn't seem to meet the needs described in this blog post. Most notably, it doesn't have the ability to parse a YouTube URL, and it doesn't seem to have keyboard hotkeys for maximizing efficiency when transcribing.

    • Hi Terrill,

      I'm the author of the original CapScribe application. The efforts to create a CapScribe web app (OpenCaps) ran out of funding.

      CapScribe itself continues to thrive, supported by our startup, Inclusive Media and Design Inc - which provides captioning and descriptive video services for the Web. CapScribe is one of the tools we use internally. We're constantly getting ideas for improving CapScribe from the captioning and described video jobs that comes our way.

      We continue to make CapScribe available for free to non-profits and individuals at While we have no plans to create an online version, we're continually updating software, which continues to be Mac OS X based (and sometimes fantasize about an iPad version).

      CapScribe exports to several different formats including YouTube - here's one YouTube example from the Ottawa Network for Education - .

      On the topic of video description, here's a short example of the video description output created with CapScribe from the Canadian Human Rights Museum web site ( ).

      And for entertainment purposes, here's an episode of the Andy Griffith show on YouTube ( ) created by John Stubbs, a veteran describer who worked in the broadcast field for years. (While in this instance, the captions were burned into the video, CapScribe can easily export a caption file for YouTube upload.)

      I should mention that the description itself is captioned as well in the Griffith video, and that in each case the description uses synthetic speech.

      Finally, here's one example where the Texas School for the Blind and Visually Impaired is using CapScribe to add captions to a series of short tutorials at - . In this case, the web video player used is a modified version of FlowPlayer.

  3. Hmm. My preference runs the other way. (

    I think overlapping captions present a different issue, and I'd be interesting in conversing on it.

    I, personally find reading overlapping captions, and speaker-placed captions, and captions that move all difficult and distracting.

    Granted, I don't "need" captions, they are supplemental for me. But I read fast, and I'm A.D.D.

  4. Hi Terrill.

    Surely in an educational setting there is a "fair use" or other exemption enabling people who are Deaf or have a hearing loss (or people on their behalf, such as lecturers, etc) to create a copy of the audio visual materials and make it accessible (whether by adding closed or open captions, etc)?

    In Australia, we have an exemption in our Copyright Act which specifically enables Deaf and people with a hearing loss (or people on their behalf) to use copyrighted material without requesting permission from the copyright holders and without breaching the infringement provisions of the legislation.

    The relevant section is section 200AB and I attached the relevant extract to the bottom of my comment.

    I've utilised this exemption already as a Deaf man to create an accessible version of the website and it's based on Article 13 to the TRIPS Agreement which provides for a 3 step test for exceptions to the rights of copyright owners and states:

    "Members (i.e. countries to the TRIPS Agreement) shall confine limitations or exceptions to exclusive rights to certain special cases which do not conflict with a normal exploitation of the work and do not unreasonably prejudice the legitimate interests of the right holder”.

    My site, which has open captions on all content can be seen at:

    Extract from the Australian Copyright legislation:

    SECTION 200AB:

    Use of works and other subject-matter for certain purposes

    (4) This subsection covers a use that meets all the following conditions:

    (a) the use is made by:

    (i) a person with a disability that causes difficulty in reading, viewing or hearing the work or other subject‑matter in a particular form; or

    (ii) someone else;

    (b) the use is made for the purpose of the person obtaining a reproduction or copy of the work or other subject‑matter in another form, or with a feature, that reduces the difficulty;

    (c) the use is not made partly for the purpose of obtaining a commercial advantage or profit.

    I have been an advocate on captioning for many years now and I think there is a real need to get out there and lead by doing the "right thing" rather than simply accepting the unreasonable positions of the majority of copyright holders and their ongoing failure to make their content accessible.

    Accessible Seinfeld is my first foray into this territory and I would be very interested to see this approach used in other jurisdictions such as the USA and Europe.

  5. Hi @Michael,

    I'm not an attorney, but as I understand United States copyright law, captioning video is considered an "alteration" and "derivative work", both of which are violations of copyright law if done without permission of the original rights holder. There's an article on eHow explaining this, which includes references at the bottom. After talking with folks at the AHEAD conference, some institutions are more concerned about this than others. We're legally obligated to provide access, so if we're breaking copyright law at least accessibility law would seem to be covering our backs. And honestly, who would sue us for captioning their video?

    For other types of media, we have The Chafee Amendement, which allows "authorized entities" to "reproduce or to distribute copies or phonorecords of a previously published, nondramatic literary work if such copies or phonorecords are reproduced or distributed in specialized formats exclusively for use by blind or other persons with disabilities."

    Video probably isn't a covered media under Chafee, and there's even some debate as to whether higher education disability services offices are "authorized entities". So, we in the U.S. could definitely benefit from legislation like yours in Australia.

    In the short term, one opportunity to influence change is the Advisory Commission on Accessible Instructional Materials in Post-Secondary Education for Students with Disabilities, aka the AIM Commission, who is charged with developing recommendations for change. Their final recommendations are due to the Secretary of Education and Congress on September 27.

    They're accepting public comment through the end of August 2011, so if you have stories, ideas, and solutions please send them to Janet Gronnenberg at

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