Three Video Captioning Tools

claude80By Claude Almansi
Staff Writer

First of all, thanks to:

  • Jim Shimabukuro for having encouraged me to further examine captioning tools after my previous Making Web Multimedia Accessible Needn’t Be Boring post – this has been a great learning experience for me, Jim
  • Michael Smolens, founder and CEO of DotSUB.com and Max Rozenoer, administrator of Overstream.net, for their permission to use screenshots of Overstream and DotSUB captioning windows, and for their answers to my questions.
  • Roberto Ellero and Alessio Cartocci of the Webmultimediale.org project for their long patience in explaining multimedia accessibility issues and solutions to me.
  • Gabriele Ghirlanda of UNITAS.ch for having tried the tools with a screen reader.

However, these persons are in no way responsible for possible mistakes in what follows.

Common Features

Video captioning tools are similar in many aspects: see the screenshot of a captioning window at DotSUB:

dotsub_transcribe

and at Overstream:

overstream_transcribe

In both cases, there is a video player, a lst of captions and a box for writing new captions, with boxes for the start and end time of each caption. The MAGpie desktop captioning tool (downloadable from http://ncam.wgbh.org/webaccess/magpie) is similar: see the first screenshot in David Klein and K. “Fritz” Thompson, Captioning with MAGpie, 2007 [1].

Moreover, in all three cases, captions can be either written directly in the tool, or creating by importing a file where they are separated by a blank line – and they can be exported as a file too.

What follows is just a list of some differences that could influence your choice of a captioning tool.

Overstream and DotSUB vs MAGpie

  • DotSUB and Overstream are online tools (only a browser is needed to use them, whatever the OS of the computer), whereas MAGpie is a desktop application that works with Windows and Mac OS, but not with Linux.
  • DotSUB and Overstream use SubRip (SRT) captioning [2] while MAGpie uses Synchronized Multimedia Integration Language (SMIL) captioning [3]
  • Overstream and Dotsub host the captioned result online, MAGpie does not.
  • The preparation for captioning is less intuitive with MAGpie than with Overstream or DotSUB, but on the other hand MAGpie offers more options and produces simpler files.
  • MAGpie can be used by disabled people, in particular by blind and low-sighted people using a screen reader [4], whereas DotSUB and Overstream don’t work with a screen reader.

Overstream vs DotSUB

  • The original video can be hosted at DotSUB; with Overstream, it must be hosted elsewhere.
  • DotSUB can also be used with a video hosted elsewhere, but you must link to the streaming flash .flv file, whereas with Overstream, you can link to the page of the video – but Overstream does not support all video hosting platforms.
  • If the captions are first written elsewhere then imported as an .srt file, Overstream is more tolerant of coding mistakes than DotSUB – but this cuts both ways: some people might prefer to have your file rejected rather than having gaps in the captions.
  • Overstream allows more precise time-coding than DotSUB, and it also has a “zooming feature” (very useful for longish videos), which DotSUB doesn’t have.
  • DotSUB can be used as a collaborative tool, whereas Overstream cannot yet: but Overstream administrators are planning to make it possible in future.
  • With DotSUB, you can have switchable captions in different languages on one player. With Overstream, there can only be one series of captions in a given player.

How to Choose a Tool . . .

So how to choose a tool? As with knitting, first make a sample with a short video using different tools: the short descriptive lists above cannot replace experience. Then choose the most appropriate one according to your aims for captioning a given video, and what are your possible collaborators’ availability, IT resources, and abilities.

. . . Or Combine Tools

The great thing with these tools is that you can combine them:

As mentioned in my former Making Web Multimedia Accessible Needn’t Be Boring post, I had started captioning “Missing in Pakistan” a year ago on DotSUB, but gone on using MAGpie for SMIL captioning (see result at [5] ). But when Jim Shimabukuro suggested this presentation of captioning tools, I found my aborted attempt at DotSUB. As you can also do the captioning there by importing a .srt file, I tried to transform my “.txt for SMIL” file of the English captions into a .srt file. I bungled part of the code, so DotSUB refused the file. Overstream accepted it, and I corrected the mistakes using both. Results at [6] (DotSUB) and [7] (Overstream) . And now that I have a decent .srt file for the English transcript, I could also use it to caption the video at YouTube or Google video: see YouTube’s “Video Captions: Help with Captions” [8]. (Actually, there is a freeware program called Subtitle Workshop [9] that could apparently do this conversion cleanly, but it is Windows-only and I have a Mac.)

This combining of tools could be useful even for less blundering people. Say one person in a project has better listening comprehension of the original language than the others, and prefers Overstream: s/he could make the first transcript there, export the .srt file, which then could be mported in DotSUB to produce a transcript that all the others could use to make switchable captions in other languages. If that person with better listening comprehension were blind, s/he might use MAGpie to do the transcript, and s/he or someone else could convert it to a .srt fil that could then be uploaded either to DotSUB or Overstream. And so on.

Watch Out for New Developments

I have only tried to give an idea of three captioning tools I happen to be acquainted with, as correctly as I could. The complexity of making videos accessible and in particular of the numerous captioning solutions is illustrated in the Accessibility/Video Accessibility section [10] of the Mozilla wiki – and my understanding of tech issues remains very limited.

Moreover, these tools are continuously progressing. Some have disappeared – Mojiti, for instance – and other ones will probably appear. So watch out for new developments.

For instance, maybe Google will make available the speech-to-text tool that underlies its search engine for the YouTube videos of the candidates to the US presidential elections (see “”In their own words”: political videos meet Google speech-to-text technology” [11]): transcribing remains the heavy part of captioning and an efficient, preferably online speech-to-text tool would be an enormous help.

And hopefully, there will soon be an online, browser-based and accessible SMIL generating tool. SubRip is great, but with SMIL, captions stay put under the video instead of invading it, and thus you can make longer captions, which simplifies the transcription work. Moreover, SMIL is more than just a captioning solution: the SMIL “hub” file can also coordinate a second video for sign language translation, and audio descriptions. Finally, SMIL is a W3C standard, and this means that when the standard gets upgraded, it still “degrades gracefully” and the full information is available to all developers using it: see “Synchronized Multimedia Integration Language (SMIL 3.0) – W3C Recommendation 01 December 2008 [12].

Green Computing: How to Reduce Our Personal Carbon Footprints

thompson80By John Thompson
Staff Writer
22 November 2008

“I’d put my money on the sun and solar energy. What a source of power! I hope we don’t have to wait until oil and coal run out before we tackle that.” That quote sounds quite timely as President-elect Obama made “green energy” part of his vision for America’s future, including using clean energy as an engine to create millions of new “green collar” jobs. So over the course of the 2008 presidential campaign, the general public has heard about his vision for clean energy and should be primed for that issue to be addressed in his new administration. But apart from what government and business can and should do to address the energy situation, what can and should individuals do to support this initiative? Specifically, what can individual computer users do to reduce their personal carbon footprints?

However, it seems somewhat self-defeating to embark on new, costly initiatives to reduce energy costs without also first examining ways in which we can make cost saving adjustments on the personal level. With over 300 million people in the USA, if each person, or even each office or household, made a conscious effort to examine his or her own use of energy, it would seem that the multiplier effect of millions of small daily changes would yield significant results on a national scale. What are some changes that individuals can make to support green computing and reduce their technology carbon footprints? Let’s look at some ways to start making a difference by picking just a few low-hanging fruits.

thompson01Power management. Keep computers and printers turned off unless you’re using them. Or at least set computer and monitor power management controls to enter low power “sleep” mode when your system is not actively in use. And while a PC does use some power in sleep mode, it’s very small—maybe 10% of what’s needed when it’s running at full power. Also, cut down on the time a computer operates unattended before it goes into sleep mode. The US Department of Energy estimates that a PC wastes up to 400 kilowatt-hours of electricity a year just by functioning at full power even though it’s not being used. Dell reportedly has saved almost $2 million and avoided 11,000 tons of CO2 emissions in one year through a global power-management initiative that calls for its employees to say “nighty-night” daily to their PCs by changing the power management setup so their PCS enter sleep mode each night.

E-mail. Look at our use of e-mail, which continues to explode. Personally, a quick count shows that I have sent close to 400 personal and business-related e-mails this month, and there’s still a week left in the month. And that number is a small fraction of the hundreds that I receive each day and of the estimated several hundred billion sent daily worldwide. Use e-mail to minimize paper use, but don’t routinely print them. Add a message at the bottom of your e-mails requesting that recipients save paper by thinking twice before printing them off their screens. I’ve seen administrators who have their administrative assistants print out all e-mails so they can read and maybe reply to them. Suggest outsourcing your organization’s e-mail to Gmail as Google probably runs its data centers much more economically and greener than you do. And switching can generate cost savings and maybe increased e-mail features for users.

Online learning. By clicking to enter your course instead of driving to campus you do away with commuting and parking hassles while also eliminating your car exhaust emissions. A 2005 report on the environmental impact of providing higher education courses found, “on average, the production and provision of the distance learning courses consumed nearly 90% less energy and thompson02produced 85% fewer CO2 emissions” (p. 4). Online courses also typically reduce paper use since traditional classroom courses still use large amounts of paper (e.g., handouts). Unless your instructor assigns a textbook (many of the online courses I teach have not used a print text in years), everything is digital through e-mail or using the Internet. So if you have a choice between taking a college course in a traditional campus setting or accessing your course from work or home, consider the online choice. No campus presence equates to less energy use, but be sure to use the power management settings on your computer system and resist the temptation to print out all your online reading assignments.

All these suggestions sound doable to most folks. In addition, there are many other simple ways to reduce your personal energy use. But we aren’t talking about going totally “green” and parking your car and walking everywhere. We’re simply looking at ways you—the person reading this blog online right now—can start making a small but significant difference.

Then why are most of these simple strategies not being implemented? Why are computer users not seeking to achieve the TBL—triple bottom line (economic, environmental and social)—and save money, help protect the environment, and do what’s right for society? Is it strictly an “I didn’t know” reason, or are there other obvious and not so obvious reasons that individuals are not taking personal responsibility to reduce their own carbon footprints? Is this a nation (world?) of people with little awareness of these small yet effective changes or just plain lazy folks waiting for government and business to light the light and lead us to reduced energy consumption? What do you think?

Oh, that opening quotation? That’s from Thomas Edison—in 1931. One would hope that there is more progress on sustainable energy in the near future than in the past 77 years.  Don’t leave it up to government or your boss. Little things YOU can do can make a big difference. Making small, almost seemingly insignificant changes can yield huge cumulative results. Green computing is just a change of habit.