Accessible video recordings
This tutorial is about creating accessible videos and video recordings.
When creating an accessible video, there are some things to keep in mind.
Don't worry, it's not that complicated.
But first: what are accessible videos?
They are easy to understand for people with visual and hearing impairments,
so might contain subtitles and an audio description.
They can also be easily accessed and operated.
We will now show you how to plan your video,
and what to be aware of when recording, editing
and adding images and footage.
We provide tips on the audio description, how to easily create subtitles,
and how to post your finished video on Media.UP.
STEP 1: PLANNING THE VIDEO
It is important to consider accessibility as soon as designing the concept.
This shortens and simplifies the subsequent work enormously.
First determine the format and approximate length of your video.
For example, whether it should be short tutorials
or a recorded 90-minute lecture.
Breaking down the content into smaller units
and uploading it in several videos is user-friendly and increases the viewer's attention.
When you have decided on a format, it's best to create a
script or a simple storyboard with the stages of your presentation.
What sequence should the individual elements be presented in?
Check to see if the spoken content fits your time frame.
Ideally, the text should be read aloud and the duration of the presentation measured.
Don't forget to have everything you need for this readily available.
If you want to add presentations, graphs or images,
they should be clearly structured.
You should use high contrast colors,
especially between foreground and background.
Complementary colors such as blue and yellow have a very high contrast.
But be careful to avoid the complementary colors red and green,
because people with a red-green colorblindness cannot see any difference here.
For the best possible legibility, use sans serif fonts,
for example Arial or Helvetica.
If possible, do not use images or film excerpts decoratively,
but only when relevant in terms of content.
Make sure to respect the applicable copyrights.
You should also avoid content flashing
more than three times in one second.
This can trigger an epileptic seizure in some people.
STEP 2: RECORDING THE VIDEO
Let's get started.
The aspect ratio of your video should be 16:9,
the resolution Full HD or 4K.
Let the camera run for a few seconds before and after the presentation,
so that there is no accidental loss of content.
Assure uniform lighting conditions when filming.
Ideally, you would only use one type of light, daylight or artificial light,
so that the light retains the same intensity and color.
Avoid backlighting, so that your face remains clearly visible.
Choose a fitting frame and a clear background,
that does not distract or visually overwhelm with too many details.
To avoid background noise, close doors and windows
and mute your phone.
Rooms with carpets and curtains are advantageous
as they help to reduce room noise.
Look at the camera while you're speaking.
This will enable people with hearing impairments to read your lips.
Do not exaggerate the movement of your lips, just speak clearly and at a moderate pace.
For better sound quality, use an external microphone and not the one of the camera or your computer.
STEP 3: VIDEO EDITING
After recording, import the material into video editing software.
Employees of the University of Potsdam can use the Camtasia software free of charge.
Below this video you'll find a link and tutorials on how to use Camtasia.
Create a video with the aspect ratio 16:9 using the editing software,
same as in your recording.
Use hard cuts and avoid transition effects, these tend to be distracting.
Put a title at the beginning of your film and an imprint at the end:
Year of creation, person responsible for the video,
potentially copyright notices for images, photos, etc. that were used.
You can now export your video.
The recommended format is the mpeg4 file format with the H.264 coding.
STEP 4: AUDIO DESCRIPTION
In order for your video to be accessible for people with impaired vision,
visual elements must be verbalized.
This is particularly important if they serve more than a decorative purpose,
and the depicted information is required for understanding your lecture.
You can verbalize the images during the recording.
For example:
"I'm showing a photograph of a 19th century loom here."
Or: "This video shows workers leaving the factory."
However, if you use a lot of purely visually accessible material,
you should create an additional video of your presentation,
which contains detailed audio descriptions of all film excerpts and images.
These descriptions should answer the questions:
Who? Where? What? When?
At the same time, the audio description of film excerpts should
impair the perception of the film as little as possible.
In case of a short sequence, its content is best explained in advance.
In case of longer sequences, you should speak in between dialogues,
yet still as synchronously as possible.
Compromises are inevitable here.
STEP 5: SUBTITLES
Your video also needs subtitles.
This requires creating a subtitle file that will be added to your video later.
A subtitle file, in our case an SRT file,
is a plain text file that consists of four parts:
1.) a chronological numbering of the individual subtitles,
2.) a precise timecode that specifies when
the subtitles appear on the screen and then disappear again,
3.) the subtitle itself
and 4.) a blank line that separates one subtitle from the next.
You can create the subtitle file manually in a text editor.
It's important that you adhere exactly to the required format,
that you create the file as pure text without formatting
and finally save the text with the file extension "srt".
The manual option, however, is very complex and prone to errors.
It is much easier to either use special software
or YouTube as a tool.
To do this, a YouTube account is required, which can be set up free of charge.
First, upload your video to YouTube and change the settings to private,
so only you can see it.
Then click on "Edit video" and on "Subtitles" in the list on the left.
Now select the automatically generated subtitles and click on "Edit".
Especially with longer videos it might take a while
before the subtitles are available.
Here you can check the automatically generated subtitles and correct them if necessary.
The speech recognition is quite good, but there are almost always some errors.
Once you are satisfied, select "Publish".
Another notice:
The automated subtitling requires the legal consent of the speakers.
Servers that do not comply with the guidelines of the GDPR are used to process the voice.
You can then download the finished subtitle file.
Select the format srt here.
When naming the file, stick to the following system:
File name - dot - language code - underscore - country code - dot - srt.
For German subtitles this would be: Filename.de_DE.srt.
Pay attention to upper and lower case letters.
STEP 6: UPLOADING THE VIDEO
Now it's almost done. All you have to do is upload your video.
Log in to Media UP and click on the upload symbol.
Now select your video and upload it.
Add a title and a description,
and choose a category to publish your video in.
Then select a thumbnail as cover image of your video.
Next, add your subtitle file.
Finalize the uploading process in the next window.
Now you can integrate your video in your Moodle course.
Make sure to add a meaningful short description to the video
and, if available, add a transcript.
CHECKLIST - SUMMARY
I'll briefly summarize what to keep in mind when creating an accessible video:
First, plan the video structure.
Pay attention to the lighting, a neutral background
and your position in the frame when recording.
Verbalize visual content
and pay attention to colors, contrast and legible fonts when using images.
When editing, add a title and an imprint to your video.
Finally, create subtitles for the video.
If you ever encounter technical difficulties,
you may contact the "Zentrum für Informationstechnologie" (short: ZIM).