PDF可访问性

PDFs are a great format to share content with students. 以下是一些最佳实践 when working with PDFs to make sure they are accessible.

Scanned PDFs

• 为什么扫描的pdf文件无法访问 
  • 1. Scanned PDFs are image files, so they are not readable by screen reader software. Therefore, students who are blind or have low vision and use screen readers cannot 访问内容. Some examples of screen reader software are NVDA, JAWS, Apple VoiceOver或ChromeVox. 他们大声朗读内容给用户听.
    2. With scanned PDFs, students cannot use digital tools such as highlighting, searching 或者复制粘贴.
    3. Poorly scanned PDFs are difficult to read because the text is often grainy or blurred 或者有黑色边缘. Most students have trouble reading the content and might 感到不知所措、沮丧或分心.
• 如何修复扫描的PDF

  • Option 1: (Best option!)在网上找到原始文件或与您的 部门图书馆联络 定位可访问的版本.  如果没有可用的，则继续执行选项2.

    Option 2: Use Ally’s alternative formats to convert the document. 这个选项并不完美 而且通常需要一些补救措施.

    1. Open the document and select alternative formats at the top of the screen. 
       
       
       
    2. It is recommended to download both the OCRed PDF and HTML alternative formats to compare the visual quality (text clarity and accuracy) and accessibility.
       Note: OCR stands for Optical Character Recognition and means the document’s content is readable by screen readers, selectable and searchable.
       
       
    3. 对两种备选格式进行视觉检查. 是否所有文本都可见? Are there 只需要稍加修改? 
    4. After the visual check, use Ally to check their accessibility. 首先，复制粘贴 将HTML版本转换为Canvas页面. 然后将OCRed PDF上传到Canvas. Ally will 为他们提供可访问性分数.
       To check the accessibility of a PDF, click on the gear icon next to the document’s title. It may take a minute to generate and you may need to refresh the page.
       To check the accessibility of a Canvas page, open the page and select edit. The gear 图标将显示在屏幕的右上角.
       
       
       
    5. 修复任何剩余的可访问性问题. 如果还有很多问题，可以考虑去 back to option 1 and locating an accessible document or webpage with similar content. Consider using a slightly different document if it's accessible without converting or editing. 这可以节省你很多时间. 
• 如何使用adobeacrobatdc扫描/OCR您的PDF

  • You can also use Adobe Acrobat DC to “Scan/OCR” and “Enhance” your document. The result will be similar to Ally’s OCRed alternative format 而且通常需要一些补救措施.

    1. 打开adobeacrobatdc. Select "Scan & “OCR”选项. 如果它不在那里， 选择更多工具选项卡，找到“扫描” & OCR”，然后选择打开.
    2. 选择屏幕中上方的“增强”.
    3. 选择“扫描文件”.
    4. Select "Enhance".
    5. Upload the OCRed PDF into Canvas and check Ally's accessibility score. You may still 需要编辑文档的可访问性.

    

Untagged PDFs

Tags are essentially markers that provide structure to a PDF. 没有标签，学生 using screen readers won’t be able to accurately navigate through the document because 没有逻辑阅读顺序.

• 如何修复未标记的PDF

  • 使用Microsoft Word给文档加标签.

    1. 打开PDF并将其保存为Word文档. 
       
    2. Upload the Word document into Canvas so Ally can check its accessibility. Be sure to select the all issues button in Ally's Instructor Feedback panel. In addition to being untagged, the document could be missing a title or some images might be missing ALT text. 一次性解决所有问题可以节省你的时间.
       
    3. Edit the Word document to fix all the issues (besides tagging). 标记文档 参见下一步.
    4. 选择“另存为Adobe PDF”.
       
    5. 选择Options按钮.
       
    6. Ensure the checkbox next to “Enable Accessibility and Reflow with tagged Adobe PDF” is checked. Reflow refers to content adjustability on various screen sizes. 
       
    7. Save the tagged PDF and upload it to your course to check its accessibility. There 也许还有你需要纠正的问题. 这个方法只是第一步.
• 我可以在adobeacrobatdc中手动标记pdf文件吗?

  • Manually tagging PDFs using Adobe Acrobat DC is not recommended because it has a very high learning curve and is best done by experts in Adobe Acrobat DC.

    如有兴趣，请参阅 LinkedIn学习创建可访问的pdf课程. 注意:您必须登录才能查看本课程.

将powerpoint转换为pdf

步骤1:确保PowerPoint是可访问的.

有关更多详细信息，请参见 微软的无障碍ppt网页. 

• Color Contrast  

  • Always use high contrast templates which use dark colored fonts on light backgrounds or vice versa.

    Some high contrast templates are: Gallery, Retrospect, Savon and Dividend.您可以使用 WebAIM的颜色对比检查器.

• Font Size

  • 请使用24pt或以上字体.

• Slide Layouts

  • 使用内置的幻灯片布局，而不是文本框. 如果使用文本框，则需要 to manually set your reading order which is quite time consuming.

    有关详细信息，请参见 微软的阅读顺序网页.

    

• 独特的幻灯片标题

  • 每张幻灯片使用独特的标题. 例如，两张关于学习技巧的幻灯片可以 be named “Study Skills Part 1” and “Study Skills Part 2”.

• 为所有图像添加替代文本(ALT文本)

  • To set the ALT text, select the image and right click or select the “Format” tab in the top menu.

    然后选择编辑ALT文本.

    在框中键入图像的简要描述. 想象你正在描述它 一个盲人. 

    

• ALT文本复杂的图像

  • 对于复杂的图像，写a caption explaining the content and mark the image as “decorative”. 
    

    If the image is too complex for a caption, include a link to accessible web content, like an article or webpage, or descriptive text-based Google Document. 

    然后将图像标记为“装饰性”.”

• Hyperlinks

  • Descriptive hyperlinks provide key information for students; they can easily understand 链接把他们带到哪里. 这对于使用屏幕阅读器的学生来说是必不可少的. 

    1. Type the title of the webpage, article, or resource then highlight it and select the 插入选项卡中的链接图标. 
    2. 粘贴链接并单击ok.

    请记住:

    • 不要直接把URL粘贴到幻灯片上.
    • Do not link the words “click here” or “here” as they are not descriptive enough.

第二步:运行PowerPoint的辅助功能检查器. 

• 运行PowerPoint辅助功能检查器

  • Select the “review” tab and select “check accessibility”.

    

• 查看错误和警告

  • Review the errors and warnings in the Accessibility Checker panel that automatically 在右边打开.

    进行必要的修改. 

Step 3: Convert the PowerPoint to PDF and check its accessibility.

• 使用“另存为Adobe PDF”按钮 
  • 1. 选择“文件”和“另存为Adobe PDF”.
       
    2. Select “Options” and check the box next to “Enable accessibility and reflow with Adobe tagged PDF”. It should be enabled by default, but it’s useful to check.
       
       
    3. 然后选择“保存”. 
• 运行PDF辅助功能检查器

  • 为了确保转换成功:

    1. 在adobeacrobatdc中打开PDF.
    2. Select the accessibility checker which is represented by a purple person icon in a purple circle.  If you don’t see it in your toolbar, select the tool icon, locate 并将其添加到您的工具中.
       
    3. 在侧板中选择“辅助功能检查”.
    4. View the results and make any modifications as needed.