EPUB Annotations Use Cases and Requirements

A user decides to annotate a textual section of an EPUB publication. They select the section, trigger the annotation affordance, optionally enter a note, select a highlight mode and color. They then save the annotation. The selected section appears on the page with the chosen highlight.

A user annotates an image included in an EPUB publication. They select the image and trigger the annotation affordance. The annotation feature is then identical to the one associated with a textual selection.

A user consults an EPUB publication that includes detailed diagrams (e.g., in SVG) and images (e.g., in JPG or PNG) visualizing a research data set. They analyze the data by annotating parts of the diagrams and/or images by selecting rectangular areas of the data visualization and share these annotations with their colleagues.

A user consults an EPUB publication that includes an audio clip (e.g., in mp3 format). Thanks to the audio player offering the proper API, they select a time segment in the audio clip. The annotation feature is then identical to the one associated with a textual selection.

A user decides to bookmark a location in a reflowable EPUB publication. The cursor is located where the user clicks on the screen, or at a default location (often the top-left corner of the screen, for left-to-right content). The user triggers the bookmark affordance, optionally labels the bookmark, and saves it. A bookmark icon appears on the screen, which helps localize the bookmarked area.

A user stops reading and closes the EPUB publication. They export the EPUB publication with their notes, bookmarks, and last reading position. They then import the EPUB publication into another reading system that supports this specification. The reading system opens the EPUB publication at the last reading position, allowing them to continue reading from where they left off.

A user adds an annotation to an EPUB publication after selecting an audio segment in an audio clip. They add a textual note with rich text formatting: emphasize, italic, underline, and subtitles.

A user adds an annotation to an EPUB publication after selecting an image. They add an audio note by recording their voice; the audio clip is attached to the annotation.

A user adds an annotation to an EPUB publication after highlighting some text. They add an image note by drawing a sketch on their screen with their digital pen and attaching it to the annotation.

A user adds an annotation to an EPUB publication after highlighting some text. They select a color for the highlight and a type (e.g. solid background,underline, strikethrough, outline).

A user adds an annotation to an EPUB publication. They enter one or more keywords that will help categorizing the annotation.

A famous author annotates a book they have just written, and deals with their publisher a specific edition of the EPUB version of the book which includes these annotations. Readers buy this highly marketed edition, open it with a reading system that supports this specification, and benefit from the author's notes.

A user exports from a reading system an EPUB publication they have previously annotated. They decide to save their notes and bookmarks in the EPUB package. If they import the ebook into another reading system that supports this specification, notes and bookmarks automatically appear.

A copy-editor verifies an EPUB publication before release. They open the EPUB publication in a reading system that supports this specification, annotate text containing typos and images with missing descriptions. They export their set of annotations to a destination folder with a specific file name and provide the file to the EPUB creator. The EPUB creator associates the annotation set with the EPUB file in an editing tool that supports this specification, reviews the annotations, and corrects the EPUB accordingly.

A machine agent, such as a conformance checker or evaluation tool, analyzes a publication and produces a structured set of annotations that identify errors, warnings, relevant specification references, and proposed corrections or enhancements. The annotation set is then exchanged between production systems and reading or QA tools so that human operators can review, filter, resolve the reported issues, and re-run the tool to obtain an updated annotation set.

A teacher reads an ebook and prepares some annotations. They add a keyword to each annotation so that students can group them easily; examples of keywords include “clarification”, “question”. They export an annotation file and share this file with their students. Their name (or nickname) is attached to each annotation. The students import the same ebook and the teacher's annotation file into their reading system. Annotations prepared by the teacher appear in the ebook. Students add their own annotations to the ebook and send them back to the teacher, with keywords like “interpretation”. Their name or nickname is also attached to their annotations.

A user annotates an EPUB publication. They synchronize their notes and bookmarks with their other personal devices via a standardized Cloud mechanism supported by each of these systems.

Participants in a book club read the same EPUB publication ebook during a period of time, in a reading system that supports this specification. Each participant adds notes to the ebook, and these annotations are shared via a standardized Cloud mechanism supported by their reading system. The name of each participant appears, so that each participant can see who made which annotation.

• Support for highlights.
• Support for bookmarks.
• Support for notes.

• Support for notes in plain text and rich text formatting for (e.g., bold, italic, underline, subtitles).
• Support for audio notes
• Support for image notes.

• Support for highlight colors and styles (e.g. solid background, underline)
• Support for the language and text direction of textual notes
• Support for keyword tagging.

• Support for progression selectors, which, even if imprecise, are helpful to order annotations in a list and help position annotations if other selectors fail.
• Support for character-level selectors, which provide adequate selectors for bookmarks and last reading locations.
• Support for text range at a character level, including customizable highlights and optional notes.
• Support for full-image selection, with the same features as text annotations.
• Support for partial-image annotation at the pixel level, allowing rectangular area selection within images or diagrams.
• Support for full-audio annotation at the millisecond level.
• Support for audio segment annotation at the millisecond level, enabling time-based selection and annotation of audio clips.

• Ability to create and manage annotation threads, linking responses to original annotations.

• Ability to embed annotations within the EPUB package for distribution.
• Ability to export annotations as standalone files, including metadata identifying the ebook.
• Ability to import external annotation files and linking them to an already imported EPUB, with support for author attribution.

• Support for the persistence of annotations across EPUB updates, including structural changes (e.g., added text, modified spine, new resources).
• Support for the automatic repositioning of annotations to maintain accuracy in updated or revised EPUBs.