June 12, 2016 by tushumane
Electronic documents also known as “Soft-Copy” cannot be considered as total replacement to the conventional hard format without addressing certain issues. One of the major concerns is referencing the diagrammatic or graphical contents while reading the document. Most of the time reader has to scroll up or down to get to a reference or diagram or table on previous or next page. In this process, the reader often gets flummoxed or stuck. This has a major impact on readability, understandability, comprehensibility and hence implicitly on usability of document. To overcome this major interaction issue, concept of links is being in use for many years but is not at all effective. Using hover effects can completely eliminate this hindrance and improve the readability factor of document.
We are in era of computerization, almost anything is getting its logical, electronic representation. Documents are considered as the most primeval logical entities. Ranging from palm plates, handbooks, manual to reference books, dictionaries and novels are now available in digital formats. These digital formats are considered to be a replacement to conventional hard copy approach for dealing with the documents. There are numerous proprietary and standard digital representations of document available such as Flat Text Files (TXT), MS Office Word Files (DOC, DOCX), Rich Text Files (rtf), Open-Document Text Document (ODT) and of course most popular Portable Document Format (PDF) . Multimedia support is considered as an evolution in the digitization of documents. Most of the representational formats support to multimedia contents like images, animations, and video. After representation of diagrammatic contents or graphic contents made possible, digitized documents started taking place of hard form of documents. People think electronic document as a good replacement to hard form document because of many benefits like size, portability, durability, manageability. Yes, this is true too. But there are certain issues that need to be addressed as we evolve further. One of the issues this paper addresses is readability with respect to the diagrammatic or graphical contents. When we are using hard form of document or book we can easily turn the page, fold the page, hold the page and refer to diagram or table we want on the another page. But, what if you are reading it in PDF or WORD format?
Writer of the document cannot fit every related things on same page due to page width, height, same way while digitizing the document or while making it electronically available it is not possible to optimize it for reading. Hence comes the concept of clickable links, in which page changes to the target area of the document. But again, user has to come back where he was previously either using scroll or page down. This can be really annoying to him. We discuss the scenario:
Presently, the reader has to get back to his current page using scroll up or down. You can now imagine how disturbing this can be and how much comprehensibility is being achieved by reader in this process. This can seriously affect overall usability of electronic document utility.
Scroll Free Solution:
We can use hover effect to avoid overhead of scrolling action. When user encounters the reference all he/she has to do is to take a mouse over it and the reference will be shown in content holder. Let’s look at the figure to get clear picture.
The content holder may hold diagrams, tables or any other graphical content. Content holder will display the referred content clearly, at the same time it will be transparent enough to read through it without much efforts. Using this concept for portraying, user will be linked at comprehensive level and readability of document will be preserved. Implicitly usability of utility will improve.
The generalized procedure (regardless of format) is suggested below.
- Set Key=Reference name (e.g. figure 1.1 or diagram 1.1 or table 1.1)
- Set Value=Start and end positions of referred content. It may be a pointer or co-ordinates or simply line, column pair.
- Modify document’s metadata by adding a data structure for above key value pair.
- Add a code in document reader to adapt the same (Steps 1 to Step 3).
- Make a provision for content holder by adding suitable code in document reader.
- Whenever user encounters the reference, he/she will take a mouse over the reference, this will trigger document reader to look in document’s metadata.
- Whatever user is pointing to, is looked in to data structure we created in Step 3.
- If successful, two events will occur:
- Content holder will be brought on the page on which reader is currently on.
- Value pointed by corresponding key in lookup data structure, i.e. (line, column) range or pointer to content is referred and associated content will be loaded in to content holder.
- In rare case of unsuccessful search, simply an exception will be raised.
- As soon as reader takes out cursor from reference, content holder will be just disabled but not closed.
- Above step applies only when reader is on same page area or reader hasn’t yet hovered mouse over another reference and will ensure if reader once again hover his/her mouse over same reference, instead of repeating whole process, content holder will be just re-enabled. This will eliminate the overhead of bringing the content to and forth and hence reducing latency.
- If reader changes the page or encounters the next reference on same page, content from content holder will be removed or replaced by next referred content.
- If reader finishes reading the document or in case reader chooses to close the document, content holder will be destroyed, appropriate garbage collection mechanisms would be implemented and link between document metadata and document reader will be closed.
Note: There are two options for improving the visibility and readability while content holder is being displayed.
- Transparent content holder: Provide user with tiny slide bar for adjusting the transparency.
- Hover-to-Hover: As we are keeping the content until reader encounters next reference, reader can take his/her mouse off the reference and read the content being under covered by content holder and after reading again hovering over the reference.
An alternative approach is using machine learning, capture the referred content associated with the reference in first iteration and from next iteration make that referred content available on page containing reference.
This can be implemented in open source pdf reader like PDF-Lite or create a separate prototype to implement this from scratch. Second approach is recommended.