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PDF Rendering Extension conformance to ISO 14289-1 - paginated reports

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APPLIES TO:  Power BI Report Server  SQL Server Reporting Services paginated reports  Power BI Report Builder

This document describes paginated report PDF Rendering Extension conformance to ISO 14289-1 (PDF/UA) specifications for paginated reports in the Power BI service, Power BI Report Server, and SQL Server Reporting Services.

Note

You can save or print this whitepaper by selecting Print from your browser, then selecting Save as PDF.

Prerequisites

  • For Power BI paginated reports in the Power BI service, you need a Power BI Pro license, or Premium Per User (PPU) license, and write access to a workspace in a Power BI Premium capacity.

1. Scope

Not applicable

2. Normative references

Not applicable

3. Terms and definitions

Not applicable

4. Notation

Not applicable

5. Version Identification

The PDF Rendering Extension provides support for PDF/UA as described in this document. In some instances, noted below, it's incumbent on the user to take steps to ensure that a PDF is in full compliance with PDF/UA. We expect the user will add the appropriate PDF/UA version and conformance identifiers as the last step in this process, indicating that the necessary work has been done to make the PDF entirely PDF/UA compliant.

Everything listed in this document is based on rendering a PDF document with the device info setting AccessiblePdf set to true. In some cases, compliance limitations are due to limitations in the Report Definition Language (RDL).

6. Conformance requirements

Criteria Supporting Feature Remarks
6.1 General Supported PDF Rendering Extension creates PDF version 1.7.
6.2 Conforming files Supported with Exceptions See remarks in section 7 – File format requirements.
6.3 Conforming reader Not Applicable
6.4 Conforming assistive technology Not Applicable

7. File format requirements

Criteria Supporting Feature Remarks
7.1 General Supported with Exceptions All real content shall be tagged as defined in ISO 32000-1:2008, 14.8. Items (ISO 32000-1:2008, 14.8.2.2.2) shall not be tagged in the structure tree.
  • PDF Rendering Extension doesn't offer the flexibility to explicitly mark individual items, so it will instead group everything that maps to the criteria in ISO 32000-1:2008, 14.8.2.2.2.
    Content shall be marked in the structure tree with semantically appropriate tags in a logical reading order.
    Note 4 WCAG 2.0, Guideline 1.4 explains issues regarding contrast, color, and other formatting for accessibility.
  • The user would need to ensure that their document isn't subject to these issues.
    Standard tags defined in ISO 32000-1:2008, 14.8.4, shall not be remapped.
  • PDF Rendering Extension doesn't remap the standard tags. Documents begin with the Document root element.
    Files claiming conformance with this International Standard shall have a Suspects value of false (ISO 32000-1:2008, Table 321).
  • PDF Rendering Extension doesn't have the Suspects entry. This property is optional.
    		•
    7.2 Text Supported with Exceptions Content shall be tagged in logical reading order. The most semantically appropriate tag shall be used for each logical element in the document content.
  • PDF Rendering Extension tags content in logical reading order as much as is feasible.
    Character codes shall map to Unicode as described in ISO 32000-1:2008, 14.8.2.4.2. Characters not included in the Unicode specification may use the Unicode private use area or declare another character encoding.
    Natural language shall be declared as discussed in ISO 32000-1:2008, 14.9.2 and/or as described in ISO 32000-1:2008, 7.9.2. Changes in natural language shall be declared. Changes in natural language inside text strings (e.g. inside alternate descriptions) shall be declared using a language identifier as described in ISO 32000-1:2008, 14.9.2.2.
  • PDF Rendering extension only declares natural language at the document level
    		•
    7.3 Graphics Supported with Exceptions Graphics objects, other than text objects, shall be tagged with a Figure tag as described in ISO 32000-1:2008, 14.8.4.5, Table 340. If any of the following exceptions are true, then the graphic shall be tagged as an artifact:
  • the graphic doesn't represent meaningful content, or
  • the graphic appears as a background to a link annotation, in which case, the alternative text on the link shall describe both the graphic and the link.
  • PDF Rendering Extension tags graphics objects with the Figure tag.
    A caption accompanying a figure shall be tagged with a Caption tag.
  • PDF Rendering Extension does not currently tag captions on figures with a Caption tag.
    Figure tags shall include an alternative representation or replacement text that represents the contents marked with the Figure tag as noted in ISO 32000-1:2008, 14.7.2, Table 323.
    Note 1 See also WCAG 2.0, Guideline 1.1.
    If text represented in a graphic is not text in a natural language that's meant to be read by a human reader, alternative text describing the nature or purpose of the graphic shall be provided.
    Note 2 Text that's a type sample or a sample of the writing system used by a language are examples of text that isn't in a natural language. PDF Rendering Extension supports alt text on figures, though it's up to the user to add the alt text.
    Additional note regarding the BBox attribute:
  • PDF Rendering Extension doesn't currently write the BBox attribute.
  • A workaround is to manually retag illustrations as new Figures or as Artifacts.
    		•
    7.4 Headings Not Applicable RDL doesn't support mark up of headings in any way. It's up to the user to tag them as appropriate.
    7.5 Tables Supported with Exceptions Tables should include headers. Table headers shall be tagged according to ISO 32000-1:2008, Table 337 and Table 349.
    Note 1 Tables can contain column headers, row headers or both.
    Note 2 As much information as possible about the structure of tables needs to be available when assistive technology is relied upon. Headers play a key role in providing structural information.
  • It's up to the user to include headers in their tables. RDL and the PDF Rendering Extension provide support for row headers.
    Structure elements of type TH shall have a Scope attribute.
  • PDF Rendering Extension does include a Scope attribute on TH elements for Column and Row Members, but not for Corner cells.
    Table tagging structures shall only be used to tag content presented within logical row and/or column relationships.
  • This is dependent upon how the user has chosen to use tables in their RDL.
    		•
    7.6 Lists Not Applicable RDL does not support mark up of lists. In RDL, they are structurally a table with a single table cell.
    It's up to the user to retag them as appropriate.
    7.7 Mathematical expressions Supported with Exceptions All mathematical expressions shall be enclosed within a Formula tag as detailed in ISO 32000-1:2008, 14.8.4.5 and shall have an Alt attribute.
  • PDF Rendering Extension doesn't currently enclose math expressions within a Formula tag.
    The requirements regarding mapping of characters to Unicode shall apply to mathematical expressions as set forth in ISO 32000-1:2008, 9.10.2 and 14.8.2.4.
  • This is supported by PDF Rendering Extension.
    		•
    7.8 Page headers and footers Supported Running headers and footers shall be identified as Pagination artifacts and shall be classified as either Header or Footer subtypes as per ISO 32000-1:2008, 14.8.2.2.2, Table 330.
  • Headers or Footers are treated and tagged as artifacts.
    		•
    7.9 Notes and references Not Applicable PDF Rendering Extension doesn't support mark up of notes and references.
    It's up to the user to tag them as appropriate.
    7.10 Optional content Not Applicable
    7.11 Embedded files Not Applicable
    7.12 Article threads Not Applicable
    7.13 Digital signatures Not Applicable
    7.14 Non-interactive forms Not Applicable
    7.15 XFA Not Applicable
    7.16 Security Not Applicable
    7.17 Navigation Supported A document should include a document outline that matches the reading order and level of navigational targets (ISO 32000-1:2008, 12.3.3).
  • RDL supports bookmarks for a report item, but the user must select this option. Those bookmarks are then rendered as a document outline by the PDF Rendering Extension.
    If present, the entries in the PageLabels number tree (ISO 32000-1:2008, 7.7.2, Table 28) should be semantically appropriate.
  • The PDF Rendering Extension does not include a PageLabels number tree.
    		•
    7.18 Annotations Not Applicable RDL doesn't support annotations
    7.21 Fonts Supported
    7.21.1 General Supported
    7.21.2 Font types Supported
    7.21.3 Composite fonts Supported
    7.21.3.1 General Supported
    7.21 3.2 CIDFonts Supported
    7.21.3.3 CMaps Supported
    7.21.4 Embedding Supported
    7.21.4.1 General Supported
    7.21.4.2 Subset embedding Supported
    7.21.5 Font metrics Supported
    7.21.6 Character encodings Supported
    7.21.7 Unicode character maps Supported
    7.21.8 Use of .notdef glyph Supported

    8. Conforming reader requirements

    Not applicable

    9. AT requirements

    Not applicable

    Disclaimer

    © 2017 Microsoft Corporation. All rights reserved. The names of actual companies and products mentioned herein may be the trademarks of their respective owners. The information contained in this document represents the current view of Microsoft Corporation on the issues discussed as of the date of publication. Microsoft cannot guarantee the accuracy of any information presented after the date of publication. Microsoft regularly updates its websites with new information about the accessibility of products as that information becomes available.

    Customization of the product voids this conformance statement from Microsoft. Please consult with Assistive Technology (AT) vendors for compatibility specifications of specific AT products.

    This document is for informational purposes only. MICROSOFT MAKES NO WARRANTIES, EXPRESS OR IMPLIED, IN THIS DOCUMENT.

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