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Graphics & Colour Blindness

Approximately 5 - 10% of your students are likely to experience some form of colour blindness. Vischeck is a website that simulates different types of colour blindness, to test the perceivability of images in colour:

For image files


Writing Alternate Text

Writing descriptive yet concise alternate text is actually harder than it sounds. But it's an important skill in rendering images accessible to students with a visual disability. WebAIM has a great primer on the appropriate use of alternate text:

WebAIM's guide to writing alternate text

For instructions on how to specify alternate text for an image, refer to the media you are using above (i.e. PowerPoint, PDF or MS Word, etc.)

Accessibility Checklists

While verifying your website against a checklist is no guarantee that it will be accessible to everyone, it's a good start to ensuring that your website is usable to the greatest extent possible. University Technology Services (UTS) has prepared a handy checklist for use by web developers and content creators alike: 

UTS WCAG checklist

WebAIM also has an infographic that summarizes accessibility requirements for web designers:

WebAIM infographic

Accessible Forms

Many use their keyboard to navigate and use the web so it is important to ensure that the forms on your website can be completed using only the keyboard:

http://webaim.org/techniques/forms/


Validating Your Website

WAVE is an online tool that automatically evaluates the accessibility of your website: 

WAVE accessibility evaluator tool

Web designers and developers may also wish to validate their markup:

W3 HTML validator


Colour Contrast Checker (Text on Background)

Sufficient contrast between the font (text) colour and the background colour is integral to the perceivability of your content. WebAIM has a tool which checks the contrast ratio between the foreground and background colours (helpful to have knowledge of hexadecimal colour codes, but not necessary):

WebAIM colour contrast checker


Common Web Accessibility Errors

The more you pay attention to web accessibility, the easier it is to make a well-meaning mistake that renders your website less usable to people with disabilities. An enlightening round-up of frequently made accessibility errors is given here:

WebAIM's common web accessibility errors


JavaScript Accessibility Issues

For web designers and developers who use JavaScript in websites, WebAIM (yet again) provides an overview of how to make JavaScript more accessible:

Accessible JavaScript


Comprehensive Online Guides on Making Websites Accessible

A well-written and easily navigable set of tutorials to give web designers a solid foundation in web accessibility. Because it was written in 2002, a few principles have been deprecated (cross-reference with 'common web accessibility errors' above) but many of the practices that Pilgrim outlines are still used in accessible web design today. The tutorials may require knowledge of HTML & CSS to be meaningful to the learner.

Dive Into Accessibility tutorial

The University of Melbourne has a more targeted and up-to-date set of training links that gives a good overview of common accessibility errors on the web and how to fix them:

University of Melbourne Accessibility training

Presentation tools like PowerPoint and Prezi are invaluable parts of most instructors' technological tool kits. But they can present barriers to students with disabilities if they are not approached with accessibility in mind.

In a classroom setting, you can describe any images that are meant to convey content (i.e. those that are not decorative), and ensure that you reference aloud any important information that is on the slide or Prezi presentation. If you are providing printed handouts from the PowerPoint or Prezi application, best practices include preparing them in alternate formats (e.g. large font size and/or electronic versions) and making them available ahead of class.

In an online context, steps can be taken to optimize PowerPoint and Prezi presentations to make them accessible to all students, regardless of ability.

PowerPoint

Within PowerPoint, there are several ways of enhancing the accessibility of a presentation including adding alternate text to images, using slide layouts to arrange content in a logical order and the ability to export to HTML (a screen-readable format).

WebAIM gives a useful overview of how to use PowerPoint's accessibility features.

Prezi

Prezi is an exciting tool, but one of the key challenges around its use in education is a lack of accessibility features, and screen-reader support in particular. Given the repeated calls from the Prezi user community to comply with regulations, however, it hopefully won't be too long before Prezi prioritizes accessibility in its development cycle.

Note: Prezi presentations are not currently compliant with WCAG standards and are not accessible to all students. If you would like to use Prezi in an online teaching context, it should be an optional part of the curriculum or an alternate format should be provided.

Captioning for Videos


Captioning makes auditory information available to those who do not have access to audio. Inclusive Media cites a number of reasons to caption your web videos.

Reasons to caption web videos

McMaster Library Services has created a handy resource for close captioning at the university. Please visit McMaster Close Captioning for more information.

Closed Captioning on YouTube


YouTube supports closed captioning on its videos by allowing users to upload a closed captioning file with their video:

Using captions with YouTube

Alternatively, if you have a transcript of the audio in a plain text format, YouTube has a(n experimental) method of automatically timing it to create closed captions:

Using the automatic timing feature in YouTube

Audio Descriptions


Audio descriptions make visual information available to those who do not have access to the visual components of the video or animation.

If a video or animation is created with accessibility in mind, and important visual elements are described or referenced in the audio track, then audio descriptions are unnecessary. However, when describing the visual elements of the video is inappropriate for the content, a second version of the video that includes audio description can be created. 

Inclusive Media provide a number of reasons to describe your Web Video:

10 Reasons to describe your web video

The WCAG (Web Content Accessibility Guidelines) group provides suggestions on how to meet the audio description guideline (1.2.3. Level A):

Meeting the audio description guideline

Using extended audio description (meaning that the audio track includes pauses to fully describe visual content rather than waiting for gaps in dialogue or narration):

Meeting the audio description guideline with extended audio

Audio recordings can present a barrier for students who are deaf or hard of hearing, as well as students with an auditory processing disorder or certain learning disabilities.

When using audio recordings in class, be prepared to provide an alternate format (a plain text transcription of the recording, for instance) on request.

If the audio recording is being accessed online, use a format that allows the recording to be paused and reviewed at the listener's discretion, and consider preparing an alternate format to be available when there is a request for it.

A comprehensive guide to has been developed by the Equity and Inclusion Office group at McMaster, which covers MS Word documents, PDF, RTF, PowerPoint and HTML:

Creating Accessible Electronic Materials

PDF Accessibility

PDFs can be made more accessible by:

  1. ensuring that the text is legible to a screen reader (vs. scanned text, which registers as a single image), 
  2. providing alternate text descriptions for images that convey information (i.e. are not decorative), and
  3. structuring the document with headers to be easily navigated by a screen reader.

WebAIM describes in depth how to leverage the accessibility features in Adobe Acrobat (a commonly used PDF-making software) and MS Word:

Accessibility Techniques for PDFs

MS Word Accessibility

Accessibility practices in MS Word are similar to those of PDFs, where using headers to structure the order of the document and alternate text to describe images are simple steps towards making the document accessible to a screen reader. A list of simple suggestions can be found on the Accessible Documents page.

WebAIM also gives an in-depth tutorial on how to use accessibility features of MS Word:

Accessibility Techniques for MS Word

SensusAccess alternate media made easy

SensusAccess is an online document conversion system supporting the transformation of text and image-based file types into different formats. Students, staff and faculty can upload files through a web interface and select from a variety of output options, including audio, Braille, or e-text formats. This service will convert text files into alternate format types as well as converting image-based files into text formatted files. MP3 audio versions are created using high-quality NeoSpeech text-to-speech voices.

Getting Started

To begin converting documents, go to the Convert a File web form to upload and choose the output format, as well as conversion options. A full list of the supported file types and output selections can be found at Conversion Options.

Conversion Results

The quality of the conversion is dependent upon the quality of the original document. For instance, if you are converting a well-structured MS Word document into audio, Daisy, or ePub format, the resulting file will be properly rendered into the desired output. If, however, you upload a poorly scanned image file for conversion to a text format, the resulting text document may include recognition errors in the output file.

Questions and Feedback

Please contact Nancy Waite in Library Accessibility Services, x26058 or

Notice: The Copyright Modernization Act (S.C. 2012, C.20) governs the making of photocopies or other reproductions of copyrighted material in Canada. The person using this service is liable for any infringement. For more information, please consult http://copyright.mcmaster.ca

The McMaster SensusAccess system offers a number of different conversion options to transform image-based and text-based documents into alternate and accessible formats. In general, text-based files may be converted to other text-based file formats or MP3 audio formats. Image-based file formats will first be converted into text-based versions using optical character recognition (OCR) before being converted to the desired format type.

The following table provide specific information as to the output options when starting with a specific file type.

Original File Formats and Output Options

ORIGINAL FILE FORMAT

AUDIO (MP3)

BRAILLE

PEF (PORTABLE EMBOSSER FORMAT)

DAISY (FULL & TEXT-ONLY)

MS WORD

RTF

TEXT

EPUB

MOBI

TAGGED PDF

.doc, .docx

Yes

Yes

Yes

Yes

No

No

Yes

Yes

Yes

Yes

.rtf

Yes

Yes

Yes

Yes

No

No

Yes

Yes

Yes

No

.txt

Yes

Yes

Yes

Yes

No

No

Yes

Yes

Yes

No

.htm, .html

Yes

Yes (ASCII)

Yes

No

No

No

Yes

Yes

Yes

Yes

ePub

No

No

No

No

No

No

No

NA

Yes

No

MOBI

No

No

No

No

No

No

No

Yes

NA

No

.pdf

Yes

Yes

Yes

No

Yes

Yes

Yes

Yes

Yes

Yes

.tiff, .jpeg, .gif, .bmp, .djv, .j2k

Yes

Yes

Yes

No

Yes

Yes

Yes

Yes

Yes

Yes

Please note that the above information is not a complete list, but represents the most commonly used files for upload and conversion. You can view all the supported files on under "Convert a File above.

Conversion Best Practices

The quality of a conversion is dependent upon the quality of the original document. Additionally, the resulting output format may include enhancements for navigation if the original file contains the appropriate semantic markup. For instance, a MS Word document containing the heading style markup for chapters (e.g., Heading 1, Heading 2, etc.) will convert into a more usable DAISY or ePub format with the relevant chapter navigation elements. The following best practices identify simple methods to prepare the file before converting in order to achieve a high-quality output.

PDF & Image-based Files

PDF and image-based files will be processed using optical character recognition (OCR) to create a text-based version of the document.

  • If scanning the document, ensure the scanned image is free from smudges, dark marks, highlighted text, or artifacts in the image. These will affect the accuracy of the OCR process.
  • Minimize the any effects from skewing. If the image is presented at an "off-angle", the accuracy of the OCR process will be lower resulting in a lower quality text version.
  • If you are starting with an image-based format and wish to convert to a text format, you may achieve better results by initially converting to Tagged PDF and then copying/pasting the text into a MS Word document. While you can convert directly from an image file to a text file with SCRIBE, you may find better results for some image documents if converting to Tagged PDF and then to a text file (see "Converting to MS Word and Text Files" section).

Converting to MS Word and Text Files

SCRIBE will convert image-based documents into MS Word, RTF, and text files. You may also find it useful with some image-based documents to convert initially to Tagged PDF and then copy and paste the text from the Tagged PDF into MS Word. This may result in a better reading experience and may remove non-essential content.

With the MS Word version of the document, you can more accurately "clean" the content for conversion into MP3 audio or for use with assistive technologies. Most conversions will take just a few seconds within MS Word and involve the use of the Find and Replace tools. For more information on using the Find and Replace tools, see using the Find and Replace in MS Word removing special characters in a document.

Please note - in the Find and Replace examples below, replace the value with one spacebar and do not include the quotes.

Image-File to Tagged PDF to MS Word Document

  • Submit the image-based document to SCRIBE and select Tagged PDF as the output option.
  • Open the Tagged PDF and select all the text.
  • Copy and paste this into a MS Word document (Open Office may also be used).
  • Using Find and Replace:
    • Search for ".<space>^p" and replace with ".^p^p" .
    • Search for "<space>^p" and replace with "<space>" .
    • Search for "<space>•<space>" and replace with "^p•<space>" .
    • Search for "-<space>" and replace with no value.
  • Save the document in your preferred text format.

Image-File to MS Word Document

To clean-up a MS Word file for use with assistive technology or for creating MP3 files, perform a "search and replace" to remove optional hyphens and section breaks. Identify the special character you wish to find in the "Find:" box and leave the "Replace with:" box empty. See Using the Find and Replace in MS Word for additional information on removing special characters in a document.

  • Submit the image-based document to SCRIBE and select Microsoft Word as the output option.
  • Open the converted Microsoft Word document (Open Office may also be used).
  • Using Find and Replace:
    1. Search for "Optional Hyphen" under Special Formatting and replace with no value.
    2. Search for "Section Breaks" under Special Formatting and replace with "^p^p".
    3. Search for "Manual Page Breaks" and replace with "^p^p".
  • Save the document in your preferred text format.

Authoring MS Word, RTF, Text Files

  • Use Word styles to specify document headings. For example, the style "Heading 1" could be used to identify the title of the document and the style "Heading 2" could be used to identify chapter information. It is best to use only one "Heading 1" to facilitate accurate conversions into other document formats (e.g., DAISY, ePub, Braille, etc.).
  • Provide short descriptions for content-related images in your MS Word document.
  • Avoid using text-boxes in your document. If you want to customize the layout, use a Column Tool or a Section Break.
  • If converting to DAISY, page numbers will be identified based on the MS Word pagination. To obtain custom pagination, use the PageNumber style from the Save As DAISY plug-in for Microsoft Office for your custom page numbers.

Authoring HTML Files

  • Use HTML heading markup (e.g., <h1>, <h2>, etc.) to designate headings in the document. For example, the style "Heading 1" could be used to identify the title of the document and the style "Heading 2" could be used to identify chapter information.
  • Provide short descriptions for content-related images in the HTML document.